use std::fmt;
use crate::ast::{
Arg, ArgPart, Expr, IoBinding, IoStream, PipeTarget, Step, Value, WorkspaceTarget,
};
use crate::command::{
ArgSpec, ArgType, CommandMeta, Example, FlagSpec, FlagValueType, IoDirection, Stream,
split_assignment,
};
use crate::constants::{KEYWORD_EXPORT, KEYWORD_IMPORT};
use crate::error::{ParseError, ParseResult, SpanContext};
use indoc::indoc;
fn join_value(args: Vec<Arg>, cmd_name: &str) -> ParseResult<Arg> {
if args.is_empty() {
return Err(ParseError::validation(
cmd_name,
format!("{cmd_name} requires at least one argument"),
&SpanContext::line_only(0),
));
}
if args.len() == 1 {
return Ok(args.into_iter().next().unwrap());
}
if args.iter().all(|a| matches!(a, Arg::String(..))) {
return Ok(Arg::String(
args.iter()
.map(|a| a.as_str())
.collect::<Vec<_>>()
.join(" "),
false,
));
}
let mut parts = Vec::new();
for (index, arg) in args.into_iter().enumerate() {
if index > 0 {
parts.push(ArgPart::Text(" ".to_string(), false));
}
match arg {
Arg::String(text, quoted) => parts.push(ArgPart::Text(text, quoted)),
Arg::Expr(expr) => parts.push(ArgPart::Expr(expr)),
Arg::Parts(inner) => parts.extend(inner),
}
}
Ok(Arg::Parts(parts))
}
pub fn lower_env_assignment(args: Vec<Arg>) -> ParseResult<StepKind> {
let arg = args.into_iter().next().ok_or_else(|| {
ParseError::validation(
"ENV",
"ENV requires KEY=value".to_string(),
&SpanContext::line_only(0),
)
})?;
let Some((key, value)) = split_assignment(arg.as_str())
.map_err(|e| ParseError::validation("ENV", e.to_string(), &SpanContext::line_only(0)))?
else {
return Err(ParseError::validation(
"ENV",
"ENV requires KEY=value format".to_string(),
&SpanContext::line_only(0),
));
};
Ok(StepKind::Env { key, value })
}
pub(crate) fn canonical_assignment_arg(key: &str, value: &Arg) -> Arg {
Arg::String(format!("{key}={}", value.render()), false)
}
fn fmt_assert_target(target: &AssertTarget) -> String {
match target {
AssertTarget::Value(arg) => fmt_value(arg, quote_msg),
_ => target.render(),
}
}
fn fmt_value(arg: &Arg, quote: fn(&str) -> String) -> String {
match arg {
Arg::Expr(_) => arg.render(),
Arg::String(text, _) => quote(text),
Arg::Parts(_) => {
let rendered = arg.render();
if rendered.contains(';')
|| rendered.contains('}')
|| rendered.contains('\n')
|| rendered.contains('\r')
{
quote(&rendered)
} else {
rendered
}
}
}
}
fn quote_arg(s: &str) -> String {
let is_safe = s.chars().all(|c| c.is_ascii_alphanumeric() || c == '_')
&& !s.starts_with(|c: char| c.is_ascii_digit() || c == '-' || c == '/' || c == '.')
&& !crate::Command::is_statement_keyword(s);
if is_safe && !s.is_empty() {
s.to_string()
} else {
format!("\"{}\"", s.replace('\\', "\\\\").replace('"', "\\\""))
}
}
fn quote_msg(s: &str) -> String {
let safe = s.chars().all(|c| c.is_ascii_alphanumeric() || c == '_')
&& !s.starts_with(|c: char| c.is_ascii_digit())
&& !crate::Command::is_statement_keyword(s);
if safe && !s.is_empty() {
s.to_string()
} else {
format!("\"{}\"", s.replace('\\', "\\\\").replace('"', "\\\""))
}
}
fn quote_run(s: &str) -> String {
if s.is_empty() || s.chars().any(|c| c == ';' || c == '\n') || s.contains("//") {
return format!("\"{}\"", s.replace('\\', "\\\\").replace('"', "\\\""));
}
s.split(' ')
.map(|w| {
if w.starts_with(|c: char| c.is_ascii_digit())
|| w.starts_with(['/', '.', '-', ':', '='])
{
format!("\"{}\"", w.replace('\\', "\\\\").replace('"', "\\\""))
} else {
w.to_string()
}
})
.collect::<Vec<_>>()
.join(" ")
}
fn fmt_exec_arg(arg: &Arg) -> String {
match arg {
Arg::String(text, _) => {
format!("\"{}\"", text.replace('\\', "\\\\").replace('"', "\\\""))
}
Arg::Expr(_) => arg.render(),
Arg::Parts(_) => {
let rendered = arg.render();
if rendered.contains(';')
|| rendered.contains('}')
|| rendered.contains('\n')
|| rendered.contains('\r')
{
format!(
"\"{}\"",
rendered.replace('\\', "\\\\").replace('"', "\\\"")
)
} else {
rendered
}
}
}
}
fn fmt_raw_arg(arg: &Arg) -> String {
match arg {
Arg::String(s, true) => format!("\"{}\"", s.replace('\\', "\\\\").replace('"', "\\\"")),
_ => arg.render(),
}
}
fn fmt_io(b: &IoBinding) -> String {
let s = match b.stream {
IoStream::Stdin => "stdin",
IoStream::Stdout => "stdout",
IoStream::Stderr => "stderr",
};
match &b.pipe {
Some(PipeTarget::Var(v)) => format!("{}=${}", s, v),
None => s.to_string(),
}
}
pub(crate) fn is_known_command(name: &str) -> bool {
if name == "ELSE" {
return true;
}
all_metadata().iter().any(|meta| meta.name == name)
}
pub(crate) fn invalid_syntax_error(name: &str, raw_args: &[Arg]) -> ParseError {
let received = raw_args
.iter()
.map(Arg::render)
.collect::<Vec<_>>()
.join(" ");
let got = if received.is_empty() {
"nothing".to_string()
} else {
format!("`{received}`")
};
let found = if received.is_empty() {
None
} else {
Some(received.clone())
};
let expected = all_metadata()
.iter()
.find(|meta| meta.name == name)
.map(|meta| vec![meta.syntax.to_string()])
.unwrap_or_default();
let ctx = SpanContext::line_only(0);
match structural_hint(name, &received) {
Some(hint) => ParseError::invalid_syntax(
name,
format!("invalid syntax for command {name}: {hint}"),
found,
expected,
Some(hint),
&ctx,
),
None => ParseError::invalid_syntax(
name,
format!("invalid syntax for command {name}: got {got}."),
found,
expected,
None,
&ctx,
),
}
}
fn unknown_command_error(name: &str, raw_args: &[Arg]) -> ParseError {
let received = raw_args
.iter()
.map(Arg::render)
.collect::<Vec<_>>()
.join(" ");
let hint = structural_hint(name, &received).or_else(|| case_hint(name));
let ctx = SpanContext::line_only(0);
match hint {
Some(hint) => ParseError::unknown_command(
name,
format!("unknown command: {name}\n{hint}"),
Some(hint),
&ctx,
),
None => ParseError::unknown_command(name, format!("unknown command: {name}"), None, &ctx),
}
}
pub(crate) fn classify(name: &str, raw_args: &[Arg]) -> ParseError {
if is_known_command(name) {
invalid_syntax_error(name, raw_args)
} else {
unknown_command_error(name, raw_args)
}
}
fn structural_hint(name: &str, received: &str) -> Option<String> {
let got = if received.is_empty() {
"nothing".to_string()
} else {
format!("`{received}`")
};
match name {
"WITH_IO" => Some(with_io_hint(&got, received)),
"AWAIT" => Some(format!(
"AWAIT waits for a background task variable, e.g. `LET $t: HANDLE = ASYNC ECHO hi` then `AWAIT $t`; got {got}."
)),
"CANCEL" => Some(format!(
"CANCEL stops a background task variable, e.g. `CANCEL $t` (from `LET $t: HANDLE = ASYNC ...`); got {got}."
)),
"ASYNC" => Some(format!(
"ASYNC runs a command in the background, e.g. `ASYNC RUN ...`, `ASYNC {{ ... }}`, or `LET $t: HANDLE = ASYNC ...`; got {got}."
)),
"FOR" => Some(format!(
"FOR loops need `FOR $item: TYPE IN <expr> {{ ... }}` (or `FOR $key: STRING, $value: TYPE IN <expr> {{ ... }}`); got {got}."
)),
"IF" => Some(format!(
"IF needs a condition and a block, e.g. `IF true {{ ECHO yes }}`; got {got}."
)),
"ELSE" => Some(format!(
"ELSE must directly follow an `IF ... {{ ... }}` block, e.g. `IF true {{ ECHO yes }} ELSE {{ ECHO no }}`; got {got}."
)),
"LET" => Some(format!(
"LET assigns a variable, e.g. `LET $name: STRING = <expr>`, `LET $t: HANDLE = ASYNC ...`, `LET $out: STRING = <command>` (capture), `LET $out: STRING = AWAIT $t`, or `LET $var: TYPE = {{ ... }}` (inline block); got {got}."
)),
"SET" => Some(
"`SET` is not a keyword; mutate a declared variable with `$var = <expr>`, e.g. `$count = 2`.".to_string(),
),
"TIMEOUT" => Some(format!(
"TIMEOUT needs a duration and a command or block, e.g. `TIMEOUT 30s RUN ...`; got {got}."
)),
"FUNC" => Some(format!(
"FUNC defines a function, e.g. `FUNC GREET($name: STRING) {{ RETURN $name }}`; got {got}."
)),
"RETURN" => Some(format!(
"RETURN ends the nearest function, ASYNC task, or inline LET block with a value, e.g. `RETURN $x`; got {got}."
)),
"WHILE" => Some(format!(
"WHILE needs a Bool condition and a block, e.g. `WHILE !$done {{ ... }}`; got {got}."
)),
"BREAK" => Some(
"`BREAK` exits the innermost enclosing FOR/WHILE loop; it must appear inside a loop.".to_string(),
),
"CONTINUE" => Some(
"`CONTINUE` skips to the next iteration of the innermost enclosing FOR/WHILE loop; it must appear inside a loop.".to_string(),
),
"INHERIT_ENV" => Some(format!(
"INHERIT_ENV takes a key list, e.g. `INHERIT_ENV [HOME, PATH]`; got {got}."
)),
name if name == KEYWORD_IMPORT => Some(format!(
"IMPORT brings module functions into bare-call scope, e.g. `IMPORT [STD]` or `IMPORT [STD, MOCK]`; got {got}."
)),
name if name == KEYWORD_EXPORT => Some(
"`EXPORT` is reserved for future script-module support and cannot be used yet."
.to_string(),
),
_ => None,
}
}
fn with_io_hint(got: &str, received: &str) -> String {
const SYNTAX: &str =
"WITH_IO needs `WITH_IO [bindings] <command>` or `WITH_IO [bindings] { <commands> }`";
const BINDINGS: &str = "bindings are `stdin`, `stdout`, `stderr`, or `<stream>=$var` with a PIPE-typed variable (e.g. `[stdout=$p]`, `[stdin=$p]`)";
if let Some(after_open) = received.strip_prefix('[') {
match after_open.split_once(']') {
None => {
return format!("{SYNTAX}: missing closing `]` in the binding list; got {got}.");
}
Some((bindings, _)) => {
for part in bindings.split(',') {
let part = part.trim();
if part.is_empty() {
continue;
}
let (stream, binding) = match part.split_once('=') {
Some((stream, binding)) => (stream.trim(), Some(binding.trim())),
None => (part, None),
};
if !matches!(stream, "stdin" | "stdout" | "stderr") {
return format!(
"{SYNTAX}: invalid stream `{stream}`; expected `stdin`, `stdout`, or `stderr`; got {got}."
);
}
let valid = match binding {
None => true,
Some(value) => value.strip_prefix('$').is_some_and(|var| {
!var.trim().is_empty()
&& var.chars().all(|c| c.is_ascii_alphanumeric() || c == '_')
}),
};
if !valid {
return format!(
"{SYNTAX}: invalid binding `{part}`; {BINDINGS}; got {got}."
);
}
}
}
}
}
format!("{SYNTAX}; got {got}. {BINDINGS}.")
}
fn case_hint(name: &str) -> Option<String> {
let upper = name.to_ascii_uppercase();
if upper != name
&& all_metadata()
.iter()
.any(|meta| meta.name == upper.as_str())
{
return Some(format!("did you mean `{upper}`? commands are uppercase."));
}
None
}
macro_rules! declare_commands {
(
structural [
$( $sname:ident $( { $( $sfname:ident : $sftype:ty ),* $(,)? } )? ),* $(,)?
]
$(
$cmd_ident:ident => [
name: $name:expr,
variant: $vname:ident $( { $( $vfname:ident : $vftype:ty ),* $(,)? } )? $( ( $( $ttuple:ty ),* $(,)? ) )?,
syntax: $syntax:expr,
summary: $summary:expr,
description: $desc:expr,
args: $args:expr,
flags: $flags:expr,
default_output: $out:expr,
examples: $examples:expr,
lower: $lower:expr,
]
),* $(,)?
) => {
#[derive(Debug, Clone, PartialEq)]
pub enum StepKind {
$( $vname $( { $( $vfname : $vftype ),* } )? $( ( $( $ttuple ),* ) )?, )*
$( $sname $( { $( $sfname : $sftype ),* } )?, )*
}
pub fn lower_command(name: &str, raw_args: Vec<Arg>) -> ParseResult<StepKind> {
match name {
$(
s if s == $name => {
let meta = CommandMeta {
name: $name, syntax: $syntax, summary: $summary,
description: $desc, args: $args, flags: $flags,
default_output: $out, examples: $examples,
};
let (flags, positional) = crate::strip_flags(raw_args, &meta)?;
crate::command::validate_positionals_against_meta(
s,
&meta.args,
&positional,
)?;
let lower_fn: fn(Vec<(String, Arg)>, Vec<Arg>) -> ParseResult<StepKind> = $lower;
lower_fn(flags, positional)
}
)*
_ => {
Err(classify(name, &raw_args))
}
}
}
pub fn all_metadata() -> Vec<CommandMeta> {
let mut out = vec![
$( CommandMeta {
name: $name, syntax: $syntax, summary: $summary,
description: $desc, args: $args, flags: $flags,
default_output: $out, examples: $examples,
}, )*
];
out.extend(all_structural_metadata());
out
}
};
}
#[derive(Debug, Clone, PartialEq)]
pub enum AssertTarget {
Value(Arg),
Stdout,
Stderr,
}
impl AssertTarget {
pub fn render(&self) -> String {
match self {
AssertTarget::Value(arg) => arg.render(),
AssertTarget::Stdout => "stdout".to_string(),
AssertTarget::Stderr => "stderr".to_string(),
}
}
}
fn lower_assert_target(arg: Arg) -> ParseResult<AssertTarget> {
match arg {
Arg::Expr(_) => Ok(AssertTarget::Value(arg)),
Arg::String(text, quoted) if !quoted => match text.as_str() {
"stdout" => Ok(AssertTarget::Stdout),
"stderr" => Ok(AssertTarget::Stderr),
_ => Ok(AssertTarget::Value(lower_assert_operand(Arg::String(
text, false,
)))),
},
other => Ok(AssertTarget::Value(lower_assert_operand(other))),
}
}
fn lower_assert_operand(arg: Arg) -> Arg {
match arg {
Arg::String(text, false) => {
if let Ok(i) = text.parse::<i64>() {
Arg::Expr(Expr::Literal(Value::int(i)))
} else if text.contains('.') && text.parse::<f64>().is_ok() {
Arg::Expr(Expr::Literal(Value::float(
text.parse::<f64>().unwrap_or(f64::NAN),
)))
} else if text == "true" {
Arg::Expr(Expr::Literal(Value::bool(true)))
} else if text == "false" {
Arg::Expr(Expr::Literal(Value::bool(false)))
} else {
Arg::String(text, false)
}
}
other => other,
}
}
declare_commands! {
structural [
WithIo { bindings: Vec<IoBinding>, cmd: Box<StepKind> },
WithIoBlock { bindings: Vec<IoBinding> },
For { key_var: Option<String>, key_type: Option<String>, var: String, var_type: String, in_expr: Expr, body: Vec<Step> },
If { cond: Box<Expr>, then_body: Vec<Step>, else_ifs: Vec<(Box<Expr>, Vec<Step>)>, else_body: Option<Vec<Step>> },
Assign { var: String, decl_type: String, expr: Expr },
Set { var: String, expr: Expr },
AssignCapture { var: String, decl_type: String, cmd: Box<StepKind> },
AwaitCapture { out_var: String, out_type: String, task_var: String },
AsyncBlock { body: Vec<Step> },
AssignAsync { var: String, decl_type: String, body: Vec<Step> },
Await { var: String },
Cancel { var: String },
Timeout { duration: Arg, body: Vec<Step> },
RunExec { argv: Vec<Arg> },
FuncDef { name: String, params: Vec<(String, String)>, body: Vec<Step> },
Call { name: String, args: Vec<Expr> },
Return { expr: Box<Expr> },
While { cond: Box<Expr>, body: Vec<Step> },
Break,
Continue,
]
Workdir => [
name: "WORKDIR",
variant: Workdir(Arg),
syntax: "WORKDIR <path>",
summary: "Change the working directory.",
description: indoc! {r#"
Sets the current working directory.
Relative paths resolve against the current directory; `/` resets to
the workspace root. Paths cannot escape the workspace.
"#},
args: &[ ArgSpec { name: "path", arg_type: ArgType::Path, description: "Directory to change to", io: IoDirection::Write, index: 0, required: true, fallback_stream: None } ],
flags: &[],
default_output: None,
examples: &[ Example { name: "change working directory", fence_meta: None, code: indoc! {r#"
# Later relative paths resolve under the new directory.
WORKDIR project/src
WRITE generated.txt generated-under-workdir
LET $body: STRING = READ generated.txt
ASSERT_EQ $body "generated-under-workdir"
"#} }, Example { name: "workdir in a scoped block", fence_meta: None, code: indoc! {r#"
# The block reverts to the starting directory on exit.
LET $outside: STRING = CWD
MKDIR project
[bool:true] {
WORKDIR project
WRITE inner.txt inner
}
LET $back: STRING = CWD
ASSERT_EQ $back $outside
LET $body: STRING = READ project/inner.txt
ASSERT_EQ $body "inner"
"#} } ],
lower: |_flags, args| {
let path = args.into_iter().next().ok_or_else(|| ParseError::validation("WORKDIR", "WORKDIR requires a path".to_string(), &SpanContext::line_only(0)))?;
Ok(StepKind::Workdir(path))
},
],
Workspace => [
name: "WORKSPACE",
variant: Workspace(WorkspaceTarget),
syntax: "WORKSPACE (SNAPSHOT|LOCAL|CACHE|SYSTEM) [--local]",
summary: "Switch workspace roots.",
description: indoc! {r#"
Switches the workspace root. The selection reverts at scope
exit like `WORKDIR`.
- `SNAPSHOT`: the materialized build snapshot (the default).
- `LOCAL`: the local workspace directory.
- `CACHE`: a persistent per-project directory shared across
runs, never evicted. It lives under the OS user cache
(`OXDOCK_CACHE_DIR` pins an exact directory);
`WORKSPACE CACHE --local` keeps it in
`<project>/.cache/workspace` instead.
- `SYSTEM`: full filesystem access. Scripts using it are not
hermetic.
"#},
args: &[ ArgSpec { name: "target", arg_type: ArgType::OneOf(&["SNAPSHOT", "LOCAL", "CACHE", "SYSTEM"]), description: "Target root", io: IoDirection::Write, index: 0, required: true, fallback_stream: None } ],
flags: &[ FlagSpec { name: "local", long: "--local", value_type: FlagValueType::Flag, required: false, description: "Use the project-local cache directory instead of the OS user cache (CACHE only)" } ],
default_output: None,
examples: &[ Example { name: "switch roots", fence_meta: None, code: indoc! {r#"
IMPORT [STD]
WORKSPACE LOCAL
LET $t: STRING = PATH_TYPE(".")
ASSERT_EQ $t "dir"
"#} }, Example { name: "workspace cache in a scoped block", fence_meta: None, code: indoc! {r#"
[bool:true] {
WORKSPACE CACHE
WRITE cached.txt cached-content
}
COPY --from-workspace CACHE cached.txt restored.txt
LET $body: STRING = READ restored.txt
ASSERT_EQ $body "cached-content"
"#} } ],
lower: |flags, args| {
let local = flags.iter().any(|(k, _)| k == "local");
let target = args.into_iter().next().ok_or_else(|| ParseError::validation("WORKSPACE", "WORKSPACE requires a target".to_string(), &SpanContext::line_only(0)))?;
match target.as_str() {
"SNAPSHOT" | "LOCAL" | "SYSTEM" if local => Err(ParseError::validation("WORKSPACE", "WORKSPACE --local requires CACHE".to_string(), &SpanContext::line_only(0))),
"SNAPSHOT" => Ok(StepKind::Workspace(WorkspaceTarget::Snapshot)),
"LOCAL" => Ok(StepKind::Workspace(WorkspaceTarget::Local)),
"CACHE" => Ok(StepKind::Workspace(WorkspaceTarget::Cache { local })),
"SYSTEM" => Ok(StepKind::Workspace(WorkspaceTarget::System)),
other => Err(ParseError::validation("WORKSPACE", format!("unknown workspace target: {other}"), &SpanContext::line_only(0))),
}
},
],
Env => [
name: "ENV",
variant: Env { key: String, value: Arg },
syntax: "ENV KEY=value",
summary: "Set an environment variable.",
description: indoc! {r#"
Inserts or updates an env var.
The value uses the unified string-value rules shared by every command:
`"..."` or `'...'` quotes keep exact bytes (spaces, tabs), a lone `$var`
evaluates that variable, `{{ ... }}` placeholders interpolate, unquoted
words join with single spaces, and the first `=` splits key from value
(`KEY=a=b` stores `a=b`).
A `$var` inside larger text stays literal — write `{{ $var }}` to
interpolate there.
"#},
args: &[ ArgSpec { name: "assignment", arg_type: ArgType::String, description: "KEY=value pair; the value resolves as STRING", io: IoDirection::Write, index: 0, required: true, fallback_stream: None } ],
flags: &[],
default_output: None,
examples: &[
Example { name: "set env", fence_meta: None, code: indoc! {r#"
ENV APP_MODE=production
LET $mode: STRING = env:APP_MODE
ASSERT_EQ $mode "production"
"#} },
Example { name: "quoted value with spaces", fence_meta: None, code: indoc! {r#"
# Quotes keep the space: SET_FORTH stores `outer scope`.
ENV SET_FORTH="outer scope"
WRITE out.txt "{{ env:SET_FORTH }}"
LET $body: STRING = READ out.txt
ASSERT_EQ $body "outer scope"
"#} },
Example { name: "variable value", fence_meta: None, code: indoc! {r#"
# A lone $var evaluates, like ECHO $var.
LET $who: STRING = "Alice"
ENV GREETING=$who
WRITE out.txt "{{ env:GREETING }}"
LET $body: STRING = READ out.txt
ASSERT_EQ $body "Alice"
"#} },
Example { name: "all value forms agree", fence_meta: None, code: indoc! {r#"
# A bare variable, a quoted literal, and a template all
# store plain strings through the same value rules.
LET $x: STRING = "Ada"
ENV A=$x
ENV B="hello world"
ENV C="{{ $x }} concatenated"
WRITE check.txt "{{ env:A }}|{{ env:B }}|{{ env:C }}"
LET $body: STRING = READ check.txt
ASSERT_EQ $body "Ada|hello world|Ada concatenated"
"#} },
Example { name: "scoped env reverts", fence_meta: None, code: indoc! {r#"
# ENV inside a braced block reverts when the block exits
ENV MODE=production
[bool:true] {
ENV MODE=staging
WRITE inner.txt "{{ env:MODE }}"
}
WRITE outer.txt "{{ env:MODE }}"
LET $inner_body: STRING = READ inner.txt
ASSERT_EQ $inner_body "staging"
LET $outer_body: STRING = READ outer.txt
ASSERT_EQ $outer_body "production"
"#} },
Example { name: "shell reads env per platform", fence_meta: None, code: indoc! {r#"
# A shell command reads its own environment, with
# per-platform spelling: quoted "$VAR" passes the parser
# through untouched on unix ...
ENV PROXY_PORT=23791
[unix] LET $o: STRING = RUN echo serving on "$PROXY_PORT"
# ... while cmd expands %VAR% on Windows.
[windows] LET $o: STRING = RUN echo serving on %PROXY_PORT%
ASSERT_CONTAINS $o "23791"
"#} },
],
lower: |_flags, args| lower_env_assignment(args),
],
InheritEnv => [
name: "INHERIT_ENV",
variant: InheritEnv { keys: Vec<String> },
syntax: "INHERIT_ENV [<key>, ...]",
summary: "Inherit env vars from host.",
description: indoc! {r#"
Declares which host environment variables to inherit into the script.
Must appear before any other commands and at most once. Without this
directive, the script starts with an empty environment.
"#},
args: &[ ArgSpec { name: "keys", arg_type: ArgType::Rest(&ArgType::String), description: "Host variables to inherit", io: IoDirection::Read, index: 0, required: false, fallback_stream: None } ],
flags: &[],
default_output: None,
examples: &[ Example { name: "inherit env", fence_meta: None, code: indoc! {r#"
INHERIT_ENV [PATH, HOME]
LET $path: STRING = env:PATH
ASSERT_CONTAINS $path ":"
"#} } ],
lower: |_flags, args| {
let keys = args.into_iter().map(|a| a.as_str().to_string()).collect();
Ok(StepKind::InheritEnv { keys })
},
],
Echo => [
name: "ECHO",
variant: Echo(Arg),
syntax: "ECHO <message>",
summary: "Print to stdout.",
description: "Outputs message to stdout.",
args: &[ ArgSpec { name: "message", arg_type: ArgType::Rest(&ArgType::String), description: "Text", io: IoDirection::Write, index: 0, required: true, fallback_stream: None } ],
flags: &[],
default_output: Some(Stream::Stdout),
examples: &[
Example { name: "echo", fence_meta: None, code: indoc! {r#"
ECHO build-complete
ASSERT_CONTAINS stdout "build-complete"
"#} },
Example { name: "variables", fence_meta: None, code: indoc! {r#"
# {{ }} interpolates inside text; a lone $var evaluates on its own.
LET $x: STRING = "World"
ECHO "braced:{{ $x }}"
ECHO $x
ASSERT_EQ stdout "braced:World\nWorld\n"
"#} },
],
lower: |_flags, args| Ok(StepKind::Echo(join_value(args, "ECHO")?)),
],
Run => [
name: "RUN",
variant: Run(Arg),
syntax: "RUN <command...> | RUN [\"exe\", \"arg\", ...]",
summary: "Execute shell command or direct executable.",
description: indoc! {r#"
Shell form (`RUN <command...>`) runs the joined command string in the
system shell (`$SHELL -c` / `COMSPEC /C`).
Exec form (`RUN ["exe", "arg", ...]`) spawns the executable directly
with no shell, so there is no shell expansion, globbing, redirection,
or pipes; use it for portable commands.
Guards and wrappers (`ASYNC`, `TIMEOUT`, `WITH_IO`, `LET`) apply to
both forms.
"#},
args: &[ ArgSpec { name: "command", arg_type: ArgType::Rest(&ArgType::String), description: "Command", io: IoDirection::Write, index: 0, required: true, fallback_stream: None } ],
flags: &[],
default_output: None,
examples: &[ Example { name: "run", fence_meta: None, code: indoc! {r#"
RUN echo hello
# Captured runs prove the output, not just the exit status.
LET $o: STRING = RUN echo hello
ASSERT_CONTAINS $o "hello"
"#} }, Example { name: "run exec form", fence_meta: None, code: indoc! {r#"
# No shell: `>` stays a literal argument, so no file is created.
IMPORT [STD]
RUN ["cargo", "--version", ">", "x.txt"]
ASSERT_CONTAINS stdout "cargo"
LET $t: STRING = PATH_TYPE("x.txt")
ASSERT_EQ $t "absent"
"#} } ],
lower: |_flags, args| match args.as_slice() {
[Arg::Expr(Expr::List(elems))] if elems.is_empty() => {
Err(ParseError::validation("RUN", "RUN requires at least one argument".to_string(), &SpanContext::line_only(0)))
}
[Arg::Expr(Expr::List(elems))] => Ok(StepKind::RunExec {
argv: elems.iter().cloned().map(Arg::Expr).collect(),
}),
_ => Ok(StepKind::Run(join_value(args, "RUN")?)),
},
],
Copy => [
name: "COPY",
variant: Copy { from_workspace: Option<WorkspaceTarget>, from: Arg, to: Arg },
syntax: "COPY [--from-workspace SNAPSHOT|LOCAL|CACHE|SYSTEM] <from> <to>",
summary: "Copy file into workspace.",
description: "Copies from host (the source is never moved or modified). Docker destination semantics: a file copied onto a directory (an existing one, or a trailing-slash spell like `out/`) is duplicated inside it under its own basename; a directory source duplicates its contents into the destination; any other destination path is created holding the copied bytes.",
args: &[
ArgSpec { name: "from", arg_type: ArgType::Path, description: "Source", io: IoDirection::Read, index: 0, required: true, fallback_stream: None },
ArgSpec { name: "to", arg_type: ArgType::Path, description: "Dest", io: IoDirection::Write, index: 1, required: true, fallback_stream: None },
],
flags: &[ FlagSpec { name: "from_workspace", long: "--from-workspace", value_type: FlagValueType::String, required: false, description: "Copy from the given workspace root instead of the build context" } ],
default_output: None,
examples: &[ Example { name: "copy", fence_meta: Some("roots:unified"), code: indoc! {r#"
# Copy to a new name, then read back.
WRITE src.txt content
COPY src.txt dst.txt
LET $body: STRING = READ dst.txt
ASSERT_EQ $body "content"
"#} }, Example { name: "copy from workspace", fence_meta: None, code: indoc! {r#"
# Same name, different contents per root: only LOCAL has ws-content.
WRITE shared.txt from-snapshot
WORKSPACE LOCAL
WRITE shared.txt ws-content
WORKSPACE SNAPSHOT
COPY --from-workspace LOCAL shared.txt ws-copy.txt
LET $body: STRING = READ ws-copy.txt
ASSERT_EQ $body "ws-content"
"#} } ],
lower: |flags, args| {
let from_workspace = flags
.iter()
.find(|(k, _)| k == "from_workspace")
.map(|(_, v)| match v.as_str() {
"SNAPSHOT" => Ok(WorkspaceTarget::Snapshot),
"LOCAL" => Ok(WorkspaceTarget::Local),
"CACHE" => Ok(WorkspaceTarget::Cache { local: false }),
"SYSTEM" => Ok(WorkspaceTarget::System),
other => Err(ParseError::validation("COPY", format!("unknown workspace source: {other}"), &SpanContext::line_only(0))),
})
.transpose()?;
let mut it = args.into_iter();
let from = it.next().ok_or_else(|| ParseError::validation("COPY", "COPY requires a source".to_string(), &SpanContext::line_only(0)))?;
let to = it.next().ok_or_else(|| ParseError::validation("COPY", "COPY requires a destination".to_string(), &SpanContext::line_only(0)))?;
Ok(StepKind::Copy { from_workspace, from, to })
},
],
CopyGit => [
name: "COPY_GIT",
variant: CopyGit { rev: Arg, from: Arg, to: Arg, include_dirty: bool },
syntax: "COPY_GIT [--include-dirty] <rev> <src> <dst>",
summary: "Copy from git revision.",
description: "Checkout and copy.",
args: &[
ArgSpec { name: "rev", arg_type: ArgType::String, description: "Rev", io: IoDirection::Read, index: 0, required: true, fallback_stream: None },
ArgSpec { name: "src", arg_type: ArgType::Path, description: "Src", io: IoDirection::Read, index: 1, required: true, fallback_stream: None },
ArgSpec { name: "dst", arg_type: ArgType::Path, description: "Dst", io: IoDirection::Write, index: 2, required: true, fallback_stream: None },
],
flags: &[ FlagSpec { name: "dirty", long: "--include-dirty", value_type: FlagValueType::Flag, required: false, description: "Include dirty" } ],
default_output: None,
examples: &[ Example { name: "git copy missing source errors", fence_meta: Some("expect_error:\"COPY source missing\""), code: indoc! {r#"COPY_GIT HEAD src.txt dst.txt"#} } ],
lower: |flags, args| {
let include_dirty = flags.iter().any(|(k, _)| k == "dirty");
let mut it = args.into_iter();
let rev = it.next().ok_or_else(|| ParseError::validation("COPY_GIT", "COPY_GIT requires a revision".to_string(), &SpanContext::line_only(0)))?;
let from = it.next().ok_or_else(|| ParseError::validation("COPY_GIT", "COPY_GIT requires a source".to_string(), &SpanContext::line_only(0)))?;
let to = it.next().ok_or_else(|| ParseError::validation("COPY_GIT", "COPY_GIT requires a destination".to_string(), &SpanContext::line_only(0)))?;
Ok(StepKind::CopyGit { rev, from, to, include_dirty })
},
],
Symlink => [
name: "SYMLINK",
variant: Symlink { from_workspace: Option<WorkspaceTarget>, from: Arg, to: Arg },
syntax: "SYMLINK [--from-workspace SNAPSHOT|LOCAL|CACHE|SYSTEM] <from> <to>",
summary: "Create symlink.",
description: "Creates symlink. A directory destination (existing, or a trailing-slash spell) receives the link under the source basename.",
args: &[
ArgSpec { name: "from", arg_type: ArgType::Path, description: "Target", io: IoDirection::Read, index: 0, required: true, fallback_stream: None },
ArgSpec { name: "to", arg_type: ArgType::Path, description: "Link", io: IoDirection::Write, index: 1, required: true, fallback_stream: None },
],
flags: &[ FlagSpec { name: "from_workspace", long: "--from-workspace", value_type: FlagValueType::String, required: false, description: "Symlink from the given workspace root instead of the build context" } ],
default_output: None,
examples: &[ Example { name: "symlink", fence_meta: Some("roots:unified"), code: indoc! {r#"
# A symlink reads like its target.
WRITE original.txt content
SYMLINK original.txt link.txt
LET $body: STRING = READ link.txt
ASSERT_EQ $body "content"
"#} }, Example { name: "symlink from workspace", fence_meta: None, code: indoc! {r#"
# Same name, different contents per root: only LOCAL has ws-content.
WRITE shared.txt from-snapshot
WORKSPACE LOCAL
WRITE shared.txt ws-content
WORKSPACE SNAPSHOT
SYMLINK --from-workspace LOCAL shared.txt ws-link.txt
LET $body: STRING = READ ws-link.txt
ASSERT_EQ $body "ws-content"
"#} } ],
lower: |flags, args| {
let from_workspace = flags
.iter()
.find(|(k, _)| k == "from_workspace")
.map(|(_, v)| match v.as_str() {
"SNAPSHOT" => Ok(WorkspaceTarget::Snapshot),
"LOCAL" => Ok(WorkspaceTarget::Local),
"CACHE" => Ok(WorkspaceTarget::Cache { local: false }),
"SYSTEM" => Ok(WorkspaceTarget::System),
other => Err(ParseError::validation("SYMLINK", format!("unknown workspace source: {other}"), &SpanContext::line_only(0))),
})
.transpose()?;
let mut it = args.into_iter();
let from = it.next().ok_or_else(|| ParseError::validation("SYMLINK", "SYMLINK requires a source".to_string(), &SpanContext::line_only(0)))?;
let to = it.next().ok_or_else(|| ParseError::validation("SYMLINK", "SYMLINK requires a target".to_string(), &SpanContext::line_only(0)))?;
Ok(StepKind::Symlink { from_workspace, from, to })
},
],
Mkdir => [
name: "MKDIR",
variant: Mkdir(Arg),
syntax: "MKDIR <path>",
summary: "Create directory.",
description: "Creates dir with parents.",
args: &[ ArgSpec { name: "path", arg_type: ArgType::Path, description: "Dir path", io: IoDirection::Write, index: 0, required: true, fallback_stream: None } ],
flags: &[],
default_output: None,
examples: &[ Example { name: "mkdir", fence_meta: None, code: indoc! {r#"
IMPORT [STD]
MKDIR deeply/nested/tree
LET $t: STRING = PATH_TYPE("deeply/nested/tree")
ASSERT_EQ $t "dir"
"#} } ],
lower: |_flags, args| Ok(StepKind::Mkdir(args.into_iter().next().ok_or_else(|| ParseError::validation("MKDIR", "MKDIR requires a path".to_string(), &SpanContext::line_only(0)))?)),
],
Ls => [
name: "LS",
variant: Ls(Option<Arg>),
syntax: "LS [<path>]",
summary: "List directory.",
description: "Lists entries.",
args: &[ ArgSpec { name: "path", arg_type: ArgType::Path, description: "Dir", io: IoDirection::Read, index: 0, required: false, fallback_stream: None } ],
flags: &[],
default_output: Some(Stream::Stdout),
examples: &[ Example { name: "ls", fence_meta: None, code: indoc! {r#"
MKDIR inventory
WRITE inventory/a.txt a
LS inventory
ASSERT_CONTAINS stdout "a.txt"
"#} } ],
lower: |_flags, args| Ok(StepKind::Ls(args.into_iter().next())),
],
Cwd => [
name: "CWD",
variant: Cwd,
syntax: "CWD",
summary: "Print working directory.",
description: "Outputs cwd.",
args: &[],
flags: &[],
default_output: Some(Stream::Stdout),
examples: &[ Example { name: "cwd", fence_meta: None, code: indoc! {r#"
CWD
# CWD tracks WORKDIR: the listing names the new directory.
MKDIR sub
WORKDIR sub
LET $c: STRING = CWD
ASSERT_CONTAINS $c "sub"
"#} } ],
lower: |_flags, _args| Ok(StepKind::Cwd),
],
Read => [
name: "READ",
variant: Read(Option<Arg>),
syntax: "READ [<path>]",
summary: "Read file to stdout.",
description: "Outputs file contents.",
args: &[ ArgSpec { name: "path", arg_type: ArgType::Path, description: "File", io: IoDirection::Read, index: 0, required: false, fallback_stream: None } ],
flags: &[],
default_output: Some(Stream::Stdout),
examples: &[ Example { name: "read", fence_meta: None, code: indoc! {r#"
WRITE note.txt "hello"
READ note.txt
LET $body: STRING = READ note.txt
ASSERT_EQ $body "hello"
"#} } ],
lower: |_flags, args| Ok(StepKind::Read(args.into_iter().next())),
],
ReadLine => [
name: "READ_LINE",
variant: ReadLine { var: String },
syntax: "READ_LINE $var",
summary: "Read one line from stdin into a variable.",
description: indoc! {r#"
Reads bytes until newline without waiting for EOF, leaving the pipe open.
Trailing newline is stripped (shell-read parity). On premature EOF
assigns accumulated bytes and returns.
"#},
args: &[ ArgSpec { name: "var", arg_type: ArgType::String, description: "Target variable (`$name`); the line binds as STRING", io: IoDirection::Write, index: 0, required: true, fallback_stream: None } ],
flags: &[],
default_output: None,
examples: &[ Example { name: "read line", fence_meta: None, code: indoc! {r#"
# The trailing newline is stripped: the variable holds exactly `first`.
LET $lines: PIPE
WITH_IO [stdout=$lines] ECHO "first"
WITH_IO [stdin=$lines] READ_LINE $reply
ASSERT_EQ $reply "first"
"#} } ],
lower: |_flags, args| {
let arg = args.into_iter().next().ok_or_else(|| ParseError::validation("READ_LINE", "READ_LINE requires a variable".to_string(), &SpanContext::line_only(0)))?;
let var = match arg {
Arg::Expr(Expr::Var(name)) => name,
Arg::String(s, _) if s.starts_with('$') || s.contains("{{") => s.trim_start_matches('$').to_string(),
other => return Err(ParseError::validation("READ_LINE", format!("READ_LINE requires a $variable, found {:?}", other), &SpanContext::line_only(0))),
};
if var.is_empty() {
return Err(ParseError::validation("READ_LINE", "READ_LINE requires a variable".to_string(), &SpanContext::line_only(0)))
}
Ok(StepKind::ReadLine { var })
},
],
Write => [
name: "WRITE",
variant: Write { path: Arg, contents: Option<Arg> },
syntax: "WRITE <path> [<contents>]",
summary: "Write to file.",
description: "Writes contents.",
args: &[
ArgSpec { name: "path", arg_type: ArgType::Path, description: "File", io: IoDirection::Write, index: 0, required: true, fallback_stream: None },
ArgSpec { name: "contents", arg_type: ArgType::Rest(&ArgType::String), description: "Content", io: IoDirection::Write, index: 1, required: false, fallback_stream: Some(Stream::Stdin) },
],
flags: &[],
default_output: None,
examples: &[ Example { name: "write", fence_meta: None, code: indoc! {r#"
WRITE output.txt hello-world
LET $body: STRING = READ output.txt
ASSERT_EQ $body "hello-world"
"#} } ],
lower: |_flags, args| {
let mut it = args.into_iter();
let path = it.next().ok_or_else(|| ParseError::validation("WRITE", "WRITE requires a path".to_string(), &SpanContext::line_only(0)))?;
let remaining: Vec<Arg> = it.collect();
let contents = if remaining.is_empty() { None } else { Some(join_value(remaining, "WRITE")?) };
Ok(StepKind::Write { path, contents })
},
],
Append => [
name: "APPEND",
variant: Append { path: Arg, contents: Option<Arg> },
syntax: "APPEND <path> [<contents>]",
summary: "Append to file.",
description: "Appends contents.",
args: &[
ArgSpec { name: "path", arg_type: ArgType::Path, description: "File", io: IoDirection::Write, index: 0, required: true, fallback_stream: None },
ArgSpec { name: "contents", arg_type: ArgType::Rest(&ArgType::String), description: "Content", io: IoDirection::Write, index: 1, required: false, fallback_stream: Some(Stream::Stdin) },
],
flags: &[],
default_output: None,
examples: &[ Example { name: "append", fence_meta: None, code: indoc! {r#"
WRITE log.txt line1
APPEND log.txt line2
# APPEND concatenates with no separator.
LET $all: STRING = READ log.txt
ASSERT_EQ $all "line1line2"
"#} } ],
lower: |_flags, args| {
let mut it = args.into_iter();
let path = it.next().ok_or_else(|| ParseError::validation("APPEND", "APPEND requires a path".to_string(), &SpanContext::line_only(0)))?;
let remaining: Vec<Arg> = it.collect();
let contents = if remaining.is_empty() { None } else { Some(join_value(remaining, "APPEND")?) };
Ok(StepKind::Append { path, contents })
},
],
Expand => [
name: "EXPAND",
variant: Expand { path: Option<Arg>, overrides: Vec<(String, Arg)> },
syntax: "EXPAND [<path>] [<KEY=val> ...]",
summary: "Expand a template file (or stdin) to stdout.",
description: indoc! {r#"
A template is any text file — or piped stdin when no path is given —
containing `{{ ... }}` placeholders. EXPAND replaces each placeholder
and prints the result to stdout.
Placeholders: `{{ NAME }}` reads a `KEY=val` override passed on this
command; `{{ env:NAME }}` reads an override, falling back to the
environment; `{{ $var }}` reads a script variable (dotted paths allowed).
A missing key is an error, never a silent empty.
Substitution runs in a single pass. EXPAND is not recursive and does not
expand nested placeholders: a value that itself contains `{{ ... }}` is
inserted verbatim and never expanded again.
A bare `$var` argument is a template path; `KEY=val` arguments are
overrides whose values follow the unified string-value rules (same as
`ENV`: quotes keep exact bytes, a lone `$var` evaluates,
`{{ ... }}` interpolates).
NOTE: `WRITE` interpolates `{{ ... }}` while writing, so escape it
(`\{{ ... }}`) when writing a template file for a later `EXPAND`.
With no path, the template arrives on stdin through a pipe. When piping
from a shell, single-quote the template (`echo '{{ $x }}'`): double
quotes let the shell swallow `$x`, so oxdock receives an empty `{{ }}`
placeholder and errors.
"#},
args: &[
ArgSpec { name: "path", arg_type: ArgType::Path, description: "Template file to expand; omit to expand stdin", io: IoDirection::Read, index: 0, required: false, fallback_stream: None },
ArgSpec { name: "overrides", arg_type: ArgType::Rest(&ArgType::String), description: "Template overrides shadowing that key (unified string values)", io: IoDirection::Read, index: 1, required: false, fallback_stream: None },
],
flags: &[],
default_output: Some(Stream::Stdout),
examples: &[
Example { name: "expand", fence_meta: None, code: indoc! {r#"
# Placeholders read overrides first, then the environment.
ENV NAME="Alice"
WRITE template.md "Hello {{ env:NAME }}!"
EXPAND template.md
ASSERT_CONTAINS stdout "Hello Alice!"
"#} },
Example { name: "override with spaces", fence_meta: None, code: indoc! {r#"
# WRITE would interpolate {{ }} right away, so escape it.
# The file must literally contain {{ env:NAME }} for EXPAND.
WRITE template.md "Hello \{{ env:NAME }}!"
EXPAND template.md NAME="Alice Smith"
ASSERT_CONTAINS stdout "Hello Alice Smith!"
"#} },
Example { name: "variable override", fence_meta: None, code: indoc! {r#"
# Same escaping: keep the placeholder literal until EXPAND.
# A lone $who evaluates, like ECHO $who.
LET $who: STRING = "Bob"
WRITE template.md "Hi \{{ env:WHO }}!"
EXPAND template.md WHO=$who
ASSERT_CONTAINS stdout "Hi Bob!"
"#} },
Example { name: "override forms agree", fence_meta: None, code: indoc! {r#"
# A bare variable and a template-with-tail expand identically.
LET $x: STRING = "Ada"
WRITE template.md "Hi \{{ env:NAME }} and \{{ env:NAME2 }}!"
EXPAND template.md NAME=$x NAME2="{{ $x }} concatenated"
ASSERT_CONTAINS stdout "Hi Ada and Ada concatenated!"
"#} },
Example { name: "expand stdin", fence_meta: None, code: indoc! {r#"
# No path: the template arrives on stdin through a pipe.
LET $tpl: PIPE
WITH_IO [stdout=$tpl] ECHO "Hello \{{ env:NAME }}!"
WITH_IO [stdin=$tpl] EXPAND NAME=Alice
ASSERT_CONTAINS stdout "Hello Alice!"
"#} },
Example { name: "override does not leak", fence_meta: None, code: indoc! {r#"
# KEY=val overrides shadow env for that EXPAND only.
# They never update the environment itself.
ENV NAME="Alice"
WRITE template.md "Hi \{{ env:NAME }}!"
EXPAND template.md NAME="Bob"
ASSERT_CONTAINS stdout "Hi Bob!"
EXPAND template.md
ASSERT_CONTAINS stdout "Hi Alice!"
"#} },
],
lower: |_flags, args| {
let mut path = None;
let mut overrides = Vec::new();
for arg in args {
let text = arg.as_str();
if let Some((key, value)) = split_assignment(text).map_err(|e| ParseError::validation("EXPAND", e.to_string(), &SpanContext::line_only(0)))? {
overrides.push((key, value));
} else if path.is_none() { path = Some(arg); }
else { return Err(ParseError::validation("EXPAND", "EXPAND accepts at most one path".to_string(), &SpanContext::line_only(0))) }
}
Ok(StepKind::Expand { path, overrides })
},
],
AssertEq => [
name: "ASSERT_EQ",
variant: AssertEq { hash: Option<String>, actual: AssertTarget, expected: Option<Arg> },
syntax: "ASSERT_EQ <actual> <expected> | ASSERT_EQ --hash <sha256> <actual>",
summary: "Assert strict equality.",
description: indoc! {r#"
Compares two evaluated values with typed equality (no coercion:
`INT(42)` never equals `STRING("42")`), aborting the pipeline
with a step-numbered error showing expected vs actual otherwise.
Both sides are values: `$var`, literals, templates, and calls
evaluate in memory and never touch disk. Read files explicitly
first (`LET $text: STRING = READ "out.txt"`, then
`ASSERT_EQ $text ...`).
Bare `stdout` / `stderr` observe stream buffers; a `$var`
holding a `PIPE` observes its backend bytes. `--hash` compares
the SHA-256 of a string, pipe, or captured-stdout actual
instead of the raw bytes (`stderr` is unsupported).
"#},
args: &[
ArgSpec { name: "actual", arg_type: ArgType::Any, description: "Value, stdout, stderr, or a $var holding a PIPE", io: IoDirection::Read, index: 0, required: true, fallback_stream: None },
ArgSpec { name: "expected", arg_type: ArgType::Rest(&ArgType::Any), description: "Expected (required unless --hash)", io: IoDirection::Read, index: 1, required: false, fallback_stream: None },
],
flags: &[ FlagSpec { name: "hash", long: "--hash", value_type: FlagValueType::String, required: false, description: "SHA-256" } ],
default_output: None,
examples: &[ Example { name: "assert eq", fence_meta: None, code: indoc! {r#"
LET $status: INT = 200
ASSERT_EQ $status 200
"#} },
Example { name: "assert eq file", fence_meta: None, code: indoc! {r#"
WRITE payload.bin stable-content
LET $body: STRING = READ payload.bin
ASSERT_EQ $body "stable-content"
"#} },
Example { name: "assert eq hash", fence_meta: None, code: indoc! {r#"
# --hash compares the SHA-256 digest instead of raw bytes.
WRITE payload.bin stable-content
LET $body: STRING = READ payload.bin
ASSERT_EQ --hash 08135c1b6349b0e4f894c36221952f0de00e6b4d82f80895abf359755e77103c $body
"#} } ],
lower: |flags, args| {
let hash = flags.iter().find(|(k, _)| k == "hash").map(|(_, v)| v.as_str().to_string());
let mut it = args.into_iter();
let actual = lower_assert_target(it.next().ok_or_else(|| ParseError::validation("ASSERT_EQ", "ASSERT_EQ requires a value".to_string(), &SpanContext::line_only(0)))?)?;
let remaining: Vec<Arg> = it
.map(lower_assert_operand)
.collect::<Vec<Arg>>();
let expected = if remaining.is_empty() {
if hash.is_some() {
None
} else {
return Err(ParseError::validation("ASSERT_EQ", "ASSERT_EQ requires an expected value".to_string(), &SpanContext::line_only(0)))
}
} else {
Some(join_value(remaining, "ASSERT_EQ")?)
};
Ok(StepKind::AssertEq { hash, actual, expected })
},
],
AssertContains => [
name: "ASSERT_CONTAINS",
variant: AssertContains { haystack: AssertTarget, needle: Arg },
syntax: "ASSERT_CONTAINS <haystack> <needle>",
summary: "Assert containment.",
description: indoc! {r#"
Checks containment and aborts the pipeline with a step-numbered
error otherwise: substring for strings, element match for lists,
key presence for maps, substring over stream and pipe buffers.
Like `ASSERT_EQ`, both sides are values read without implicit
I/O; read files explicitly first
(`LET $text: STRING = READ "cfg.txt"`).
Bare `stdout` / `stderr` observe stream buffers; a `$var`
holding a `PIPE` observes its backend bytes.
"#},
args: &[
ArgSpec { name: "haystack", arg_type: ArgType::Any, description: "Value, stdout, stderr, or a $var holding a PIPE", io: IoDirection::Read, index: 0, required: true, fallback_stream: None },
ArgSpec { name: "needle", arg_type: ArgType::Rest(&ArgType::Any), description: "Substring, element, or key", io: IoDirection::Read, index: 1, required: true, fallback_stream: None },
],
flags: &[],
default_output: None,
examples: &[ Example { name: "assert contains", fence_meta: None, code: indoc! {r#"
ECHO build-complete
ASSERT_CONTAINS stdout "build-complete"
"#} } ],
lower: |flags, args| {
let _ = flags;
let mut it = args.into_iter();
let haystack = lower_assert_target(it.next().ok_or_else(|| ParseError::validation("ASSERT_CONTAINS", "ASSERT_CONTAINS requires a value".to_string(), &SpanContext::line_only(0)))?)?;
let remaining: Vec<Arg> = it
.map(lower_assert_operand)
.collect::<Vec<Arg>>();
if remaining.is_empty() {
return Err(ParseError::validation("ASSERT_CONTAINS", "ASSERT_CONTAINS requires a needle".to_string(), &SpanContext::line_only(0)))
}
let needle = join_value(remaining, "ASSERT_CONTAINS")?;
Ok(StepKind::AssertContains { haystack, needle })
},
],
HashSha256 => [
name: "HASH_SHA256",
variant: HashSha256 { path: Arg },
syntax: "HASH_SHA256 <path>",
summary: "Print SHA-256.",
description: "Computes digest.",
args: &[ ArgSpec { name: "path", arg_type: ArgType::Path, description: "File", io: IoDirection::Read, index: 0, required: true, fallback_stream: None } ],
flags: &[],
default_output: Some(Stream::Stdout),
examples: &[ Example { name: "hash", fence_meta: None, code: indoc! {r#"
WRITE payload.txt hello
HASH_SHA256 payload.txt
LET $digest: STRING = HASH_SHA256 payload.txt
ASSERT_EQ $digest "2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824\n"
"#} } ],
lower: |_flags, args| Ok(StepKind::HashSha256 { path: args.into_iter().next().ok_or_else(|| ParseError::validation("HASH_SHA256", "HASH_SHA256 requires a path".to_string(), &SpanContext::line_only(0)))? }),
],
Exit => [
name: "EXIT",
variant: Exit(Arg),
syntax: "EXIT <code>",
summary: "Exit pipeline.",
description: indoc! {r#"
Stops the pipeline immediately with an `EXIT requested with code <code>`
error; steps after it never run, at any nesting depth.
Enclosing blocks still unwind their LET/ENV/WORKDIR/WORKSPACE state,
anonymous background tasks are killed synchronously, and files written
before the EXIT persist.
"#},
args: &[ ArgSpec { name: "code", arg_type: ArgType::Int, description: "Code", io: IoDirection::Write, index: 0, required: true, fallback_stream: None } ],
flags: &[],
default_output: None,
examples: &[ Example { name: "exit", fence_meta: Some("expect_error:\"EXIT requested with code 0\""), code: indoc! {r#"EXIT 0"#} } ],
lower: |_flags, args| {
let code = args.into_iter().next().ok_or_else(|| ParseError::validation("EXIT", "EXIT requires a code".to_string(), &SpanContext::line_only(0)))?;
Ok(StepKind::Exit(code))
},
],
Sleep => [
name: "SLEEP",
variant: Sleep { duration: Arg },
syntax: "SLEEP <duration>",
summary: "Pause execution for a duration.",
description: indoc! {r#"
Parks the step for the duration (e.g. 500ms, 10s, 2m).
Cooperative: checks for cancellation so an enclosing TIMEOUT or task
teardown interrupts the sleep. Cross-platform alternative to shell sleep
for testing time boundaries.
"#},
args: &[ ArgSpec { name: "duration", arg_type: ArgType::Duration, description: "How long to sleep", io: IoDirection::Write, index: 0, required: true, fallback_stream: None } ],
flags: &[],
default_output: None,
examples: &[
Example { name: "sleep", fence_meta: None, code: indoc! {r#"SLEEP 100ms"#} },
Example {
name: "sleep variable duration",
fence_meta: None,
code: indoc! {r#"
# Durations resolve at runtime, so variables work too:
# quoted or bare, both bind the same string.
LET $pause: STRING = "100ms"
SLEEP $pause
LET $bare: STRING = 100ms
SLEEP $bare
"#},
},
],
lower: |_flags, args| {
let mut it = args.into_iter();
let raw = it
.next()
.ok_or_else(|| ParseError::validation("SLEEP", "SLEEP requires a duration (e.g. SLEEP 500ms)".to_string(), &SpanContext::line_only(0)))?;
if it.next().is_some() {
return Err(ParseError::validation("SLEEP", "SLEEP takes exactly one duration argument".to_string(), &SpanContext::line_only(0)))
}
Ok(StepKind::Sleep { duration: raw })
},
],
ListAppend => [
name: "LIST_APPEND",
variant: ListAppend { list: String, item: Arg },
syntax: "LIST_APPEND $list <item>",
summary: "Append an item to a LIST variable in place.",
description: indoc! {r#"
Appends the item to the LIST variable in place.
When the binding holds the only reference the push runs in
amortized constant time. Aliased buffers detach first, so
other holders keep their contents.
"#},
args: &[
ArgSpec { name: "list", arg_type: ArgType::List, description: "Target LIST variable (`$name`)", io: IoDirection::Write, index: 0, required: true, fallback_stream: None },
ArgSpec { name: "item", arg_type: ArgType::Any, description: "Item to append (any value)", io: IoDirection::Write, index: 1, required: true, fallback_stream: None },
],
flags: &[],
default_output: None,
examples: &[ Example { name: "list append", fence_meta: None, code: indoc! {r#"
# Appends accumulate in order.
LET $items: LIST = []
LIST_APPEND $items "first"
LIST_APPEND $items "second"
LET $want: LIST = ["first", "second"]
ASSERT_EQ $items $want
"#} } ],
lower: |_flags, args| {
let mut it = args.into_iter();
let raw_list = it
.next()
.ok_or_else(|| ParseError::validation("LIST_APPEND", "LIST_APPEND requires a LIST variable (e.g. LIST_APPEND $items $x)".to_string(), &SpanContext::line_only(0)))?;
let list = match raw_list {
Arg::Expr(Expr::Var(name)) => name,
Arg::String(s, _) => s.trim_start_matches('$').to_string(),
other => return Err(ParseError::validation("LIST_APPEND", format!("LIST_APPEND requires a $variable, found {:?}", other), &SpanContext::line_only(0))),
};
if list.is_empty() {
return Err(ParseError::validation("LIST_APPEND", "LIST_APPEND requires a LIST variable (e.g. LIST_APPEND $items $x)".to_string(), &SpanContext::line_only(0)))
}
let item = it
.next()
.ok_or_else(|| ParseError::validation("LIST_APPEND", "LIST_APPEND requires an item to append (e.g. LIST_APPEND $items $x)".to_string(), &SpanContext::line_only(0)))?;
if it.next().is_some() {
return Err(ParseError::validation("LIST_APPEND", "LIST_APPEND takes exactly two arguments: LIST_APPEND $list <item>".to_string(), &SpanContext::line_only(0)))
}
Ok(StepKind::ListAppend { list, item })
},
],
}
pub fn all_structural_metadata() -> Vec<CommandMeta> {
vec![
CommandMeta {
name: "WITH_IO",
syntax: "WITH_IO [<stream>[=$var], ...] <command> | WITH_IO [bindings] { <commands> }",
summary: "Reroute standard streams.",
description: indoc! {r#"
Reroutes the standard streams of the next command or, in block form,
of every enclosed command.
Bindings map streams (`stdin`, `stdout`, `stderr`) to a PIPE-typed
variable (`stdout=$p`, `stdin=$p`), resolved from the variable
when the step runs. Both stdout and stderr pipes capture output
the same way. Declare the handle first with `LET $p: PIPE`.
Pipes hold bytes in memory and spill to a temp file above 8 MiB, so a
producer can finish before the consumer starts.
If WITH_IO wraps an ASYNC block whose body is a single RUN, guarded or
not, the pipe is a zero copy OS kernel pipe instead: pair it with a
consumer that runs while the producer is alive, since output past the
64 KiB kernel buffer stalls until drained. That promotion never crosses
a function boundary: pipes created, bound, or passed by variable inside FUNC
bodies are always script pipes, even when the surrounding task would
otherwise promote.
A second producer or consumer on a live handle is an explicit
error. A handle bound as output can later feed another
command's `stdin`, connecting commands without touching the
terminal. Binding `stdout` and `stderr` to the same live
handle fails deterministically. Merge streams in shell
via `2>&1` instead.
Nested blocks stack defaults; inline bindings override inherited ones for
their command only; closing a block restores previous wiring.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "with_io block",
fence_meta: None,
code: indoc! {r#"
LET $log: PIPE
WITH_IO [stdout=$log] {
ECHO first
ECHO second
}
WITH_IO [stdin=$log] WRITE captured.txt
# The piped bytes landed in the file.
LET $body: STRING = READ captured.txt
ASSERT_CONTAINS $body "first"
ASSERT_CONTAINS $body "second"
"#},
},
Example {
name: "variable pipe binding",
fence_meta: None,
code: indoc! {r#"
# Declare the pipe first: `LET $p: PIPE` mints a fresh
# backend without touching a stream. A plain string here
# would be a TypeMismatch.
LET $p: PIPE
WITH_IO [stdout=$p] ECHO hello
WITH_IO [stdin=$p] READ_LINE $line
ASSERT_EQ $line "hello"
"#},
},
],
},
CommandMeta {
name: "FOR",
syntax: "FOR $item: TYPE IN <expr> { <commands> } | FOR $key: STRING, $value: TYPE IN <expr> { <commands> }",
summary: "Iterate over a list or map.",
description: indoc! {r#"
The loop variable receives each element (lists) or value (maps); with
two variables, the first receives the key.
Loop variables are declared with explicit types and scoped per iteration;
they do not leak outward. The body may be a braced block
or a single-line `{ ... }` command.
`GLOB("...")` patterns must be quoted (`*` is not a bare word, so
`GLOB(*)` is a parse error); GLOB returns a root-relative sorted list,
empty when nothing matches, and rejects `..` escapes.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "for loop",
fence_meta: None,
code: indoc! {r#"
# Each element binds in turn; the loop body sees every one.
LET $items: LIST = ["a", "b"]
FOR $item: STRING IN $items {
ECHO $item
}
ASSERT_CONTAINS stdout "a"
ASSERT_CONTAINS stdout "b"
# Key and value bind together for maps.
LET $map: MAP = {"x": 1}
FOR $k: STRING, $v: INT IN $map {
ECHO "{{ $k }}={{ $v }}"
}
ASSERT_CONTAINS stdout "x=1"
"#},
},
Example {
name: "expand every match",
fence_meta: None,
code: indoc! {r#"
# Single-line body; $x is a template path, WHO an override.
IMPORT [STD]
WRITE a.txt "hi \{{ env:WHO }}!"
FOR $x: STRING IN GLOB("*.txt") { EXPAND $x WHO=World }
ASSERT_CONTAINS stdout "hi World!"
"#},
},
],
},
CommandMeta {
name: "IF",
syntax: "IF <expr> { <commands> } [ELSE IF <expr> { <commands> } ...] [ELSE { <commands> }]",
summary: "Conditional execution.",
description: indoc! {r#"
The condition is evaluated as a boolean expression.
Prefix `!` negates (`IF !false`); `&&` binds tighter than
`||`, and both short-circuit, so `IF true || $missing`
never evaluates the right side. Only Bool values are
accepted as conditions.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "if else",
fence_meta: None,
code: indoc! {r#"
IMPORT [STD]
# True branch runs; the false branch is skipped.
IF true {
WRITE yes.txt taken
} ELSE {
WRITE yes.txt skipped
}
# ELSE IF selects the first true branch.
IF false {
WRITE skipped.txt no
} ELSE IF true {
WRITE fallback.txt taken
}
# !false evaluates to true, so this branch runs.
IF !false {
WRITE negated.txt taken
}
LET $yes_body: STRING = READ yes.txt
LET $fallback_body: STRING = READ fallback.txt
LET $negated_body: STRING = READ negated.txt
ASSERT_EQ $yes_body "taken"
ASSERT_EQ $fallback_body "taken"
ASSERT_EQ $negated_body "taken"
LET $t: STRING = PATH_TYPE("skipped.txt")
ASSERT_EQ $t "absent"
"#},
},
Example {
name: "logical condition composition",
fence_meta: None,
code: indoc! {r#"
IMPORT [STD]
LET $role: STRING = "admin"
LET $level: INT = 3
# || is true when either side holds; && needs both.
IF $role == "owner" || $level >= 5 {
WRITE unexpected.txt no
} ELSE {
WRITE fallback.txt or-false
}
LET $fb: STRING = READ fallback.txt
ASSERT_EQ $fb "or-false"
LET $t1: STRING = PATH_TYPE("unexpected.txt")
ASSERT_EQ $t1 "absent"
IF $role == "admin" || $level >= 5 {
WRITE chosen.txt or-true
}
LET $ch: STRING = READ chosen.txt
ASSERT_EQ $ch "or-true"
IF $role == "admin" && $level >= 5 {
WRITE unexpected-too.txt no
} ELSE {
WRITE and.txt and-false
}
LET $an: STRING = READ and.txt
ASSERT_EQ $an "and-false"
LET $t2: STRING = PATH_TYPE("unexpected-too.txt")
ASSERT_EQ $t2 "absent"
"#},
},
],
},
CommandMeta {
name: "LET",
syntax: "LET $var: TYPE = <expr> | LET $p: PIPE | LET $var: TYPE = ASYNC { <commands> } | LET $var: TYPE = <command> | LET $var: TYPE = AWAIT $task | LET $var: TYPE = { <commands> }",
summary: "Bind script-local variables.",
description: indoc! {r#"
Declares a script-local variable with an explicit type (STRING, INT,
FLOAT, BOOL, PIPE, LIST, MAP, HANDLE, DURATION, PATH). Duplicate LET
in the same scope frame is a redeclaration error; mutate with
`$var = <expr>`.
Variables are usable in templates (`{{ $var }}`), guards, and
expressions. With `ASYNC`, spawns a background task and stores its
handle (see ASYNC). The `$` sigil on the name is mandatory.
No hoisting: a variable exists only after its LET runs, in
execution order. Reading `$var` before its LET (or after the
block that declared it exits) fails with
`undefined variable $var`. Scopes are a stack of frames and
resolution walks innermost outward, so nothing pre-declares
names. Function bodies read outer variables through the same
walk, but their own LETs never leak out (see FUNC).
The right-hand side is always an expression — literals, lists, maps,
arithmetic (`+ - * /` with `*`/`/` binding tighter, unary `-`,
parentheses), comparisons (`< <= > >=` binding tighter than
`== !=`), logical `&&` (tighter) and `||` with short-circuit,
`!` negation, `env:KEY` reads, `INSPECT($var)` snapshots,
`GLOB("*.md")`, `INT(x)` / `FLOAT(x)` conversions — never a
`{{ ... }}` template; interpolation happens in string values,
not here.
The one exception is pipes: `LET $p: PIPE` with no `=`
and no initializer mints a fresh anonymous backend,
lazily materialized at first binding, so two declarations
never share a channel.
Numbers are numeric literals: `42` binds `INT`, `3.14` binds
`FLOAT`. `Int x Int` stays `INT` (checked, integer division,
so `7 / 2` is `3`); any `Float` operand promotes to `FLOAT`.
Division by zero, overflow, and non-finite results are errors.
Both numeric sides compare numerically (`1 == 1.0` is true);
otherwise `==`/`!=` compare rendered strings and ordering on
non-numerics is a Type Error. Constant subtrees fold at parse
time and dynamic arithmetic compiles to flat RPN with
identical semantics.
Float equality is exact with no epsilon. Floats store decimals
in binary, so a value is exact only when its reduced fraction
has a power-of-2 denominator: 0.5 (1/2), 0.25 (1/4), 0.75
(3/4) are exact, while 0.1 (1/10), 0.2 (1/5), 0.3 (3/10)
repeat forever in binary (like 1/3 in decimal) and truncate,
so `0.1 + 0.2 == 0.3` is false (the sum is
`0.30000000000000004`). Rule of thumb: endings .5, .25, .75,
.125, .625, .875 are exact; .1, .2, .3 and similar are
approximations. Bound approximations instead of comparing
them: `IF $sum > 0.299999 && $sum < 0.300001`.
Comparisons do not chain: `a < b < c` is a parse error, not
`(a < b) < c`. Chaining would compare a `BOOL` against a
number (a runtime Type Error in C-style parsing) or evaluate
the middle term twice (Python-style chaining), so the grammar
accepts exactly one comparison operator per level. Write the
conjunction explicitly: `$a < $b && $b < $c`. The same holds
for equality (`$a == $b == $c` is rejected).
Captured command output is a string, so convert before math:
`LET $total: INT = $total + INT($size_str)` (`INT` trims ASCII
whitespace; `FLOAT` accepts int strings and rejects
non-finite).
Bare words need no quotes: `LET $d: STRING = 30s` binds the same string
as quoted.
When the right-hand side is a synchronous command
(`LET $out: STRING = ECHO hi`), the command runs to completion and its
exact stdout bytes are captured into the variable as a string (no newline
stripping; commands with no stdout capture as `""`; non-UTF8 stdout is
an error). Combining capture with an explicit
`WITH_IO [stdout=$var]` is a parse error.
Coming from Bash, the capture line looks familiar but behaves
strictly:
| | Bash `output=$(...)` | OxDock `LET $out: STRING = ...` |
| --- | --- | --- |
| Trailing newlines | Stripped (all of them) | Preserved byte-exact |
| Variable type | Always an untyped string | Declared: STRING, INT, FLOAT, ... |
| Math on output | Implicit: `$((var + 1))` | Explicit: `INT($out) + 1` |
| Failing command | Continues with empty output unless `set -e` | Step fails immediately, binds nothing |
`LET $out: TYPE = AWAIT $var` binds the background task's
explicit `RETURN` value instead (tasks stream their stdout
live, so there is no output left to capture); a task that
succeeded without `RETURN` yields `INT` 0, like a process
exit status.
An inline block (`LET $var: TYPE = { <commands> }`) runs its
steps in a fresh scope and binds the nearest `RETURN` value,
like a zero-arg function body: fallthrough without `RETURN`
binds `""`, and `BREAK`/`CONTINUE` escaping the block are
errors. The block reads outer variables but its own LETs
never leak out. A `{k: v}` shape still parses as a map
literal; anything else in braces is a block.
The split is deliberate: synchronous commands capture
stdout because they run inline to completion on the same
thread; background tasks never capture stdout because
concurrent output has no well-defined value. Task results
travel only through `RETURN` (or `INT` 0 for void tasks).
`LET $e: STRING = env:FOO` reads the script environment into a plain
string.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "let",
fence_meta: None,
code: indoc! {r#"
LET $name: STRING = "world"
ECHO "hello, {{ $name }}"
ASSERT_CONTAINS stdout "hello, world"
LET $items: LIST = ["a", "b"]
ASSERT_CONTAINS $items "a"
ASSERT_CONTAINS $items "b"
LET $count: INT = 42
ASSERT_EQ $count 42
"#},
},
Example {
name: "no hoisting",
fence_meta: Some("expect_error:\"undefined variable\""),
code: indoc! {r#"
# Reading before the LET runs is an error, not an empty value.
ECHO $too_early
LET $too_early: STRING = "too late"
"#},
},
Example {
name: "glob binding",
fence_meta: None,
code: indoc! {r#"
# The RHS is an expression: GLOB(...) runs and binds a list.
IMPORT [STD]
WRITE a.txt "x"
LET $files: LIST = GLOB("*.txt")
FOR $f: STRING IN $files { ECHO $f }
ASSERT_CONTAINS stdout "a.txt"
"#},
},
Example {
name: "scoped variable reverts",
fence_meta: None,
code: indoc! {r#"
# LET inside a braced block reverts when the block exits.
LET $a: STRING = "outer"
[bool:true] {
LET $a: STRING = "inner"
WRITE inner.txt "{{ $a }}"
}
WRITE outer.txt "{{ $a }}"
LET $in_body: STRING = READ inner.txt
ASSERT_EQ $in_body "inner"
LET $out_body: STRING = READ outer.txt
ASSERT_EQ $out_body "outer"
"#},
},
Example {
name: "capture command output",
fence_meta: None,
code: indoc! {r#"
# Capture keeps the trailing newline.
LET $out: STRING = ECHO hi
ASSERT_EQ $out "hi\n"
"#},
},
Example {
name: "inline block",
fence_meta: None,
code: indoc! {r#"
LET $who: STRING = "ada"
# An inline block binds its RETURN value like a function body.
LET $res: STRING = {
LET $loud: STRING = "{{ $who }}!"
RETURN $loud
}
ASSERT_EQ $res "ada!"
# Any declared type works: the block value checks like any RHS.
LET $n: INT = {
RETURN 40 + 2
}
ASSERT_EQ $n 42
"#},
},
Example {
name: "arithmetic over captured output",
fence_meta: None,
code: indoc! {r#"
# Captured output converts explicitly: INT() then arithmetic.
IMPORT [STD]
LET $size_str: STRING = ECHO 41
LET $total: INT = INT($size_str) + 1
ASSERT_EQ $total 42
# FLOAT() promotes instead of truncating.
LET $ratio: FLOAT = 1 + 2.5
ASSERT_EQ $ratio 3.5
# Int x Int stays INT: integer division truncates.
LET $half: INT = 7 / 2
ASSERT_EQ $half 3
"#},
},
Example {
name: "float equality is exact",
fence_meta: None,
code: indoc! {r#"
# Binary fractions compare cleanly; decimal fractions may not:
# 0.1 + 0.2 is 0.30000000000000004, so == is false.
IMPORT [STD]
LET $exact: BOOL = 0.5 + 0.25 == 0.75
LET $decimal: BOOL = 0.1 + 0.2 == 0.3
IF $exact {
WRITE exact.txt yes
}
IF $decimal {
WRITE unexpected.txt no
}
LET $ok: STRING = READ exact.txt
ASSERT_EQ $ok "yes"
LET $t: STRING = PATH_TYPE("unexpected.txt")
ASSERT_EQ $t "absent"
"#},
},
Example {
name: "bound inexact decimals",
fence_meta: None,
code: indoc! {r#"
# Never test inexact decimals for equality; bound them.
LET $sum: FLOAT = 0.1 + 0.2
IF $sum > 0.299999 && $sum < 0.300001 {
WRITE bounded.txt yes
}
LET $ok: STRING = READ bounded.txt
ASSERT_EQ $ok "yes"
"#},
},
Example {
name: "inspect a variable",
fence_meta: None,
code: indoc! {r#"
# INSPECT($var) snapshots a variable into a MAP: declared
# type plus live details (pipe backend stats here), so
# scripts can branch on engine state.
IMPORT [STD]
LET $p: PIPE
WITH_IO [stdout=$p] ECHO hello
LET $info: MAP = INSPECT($p)
IF $info.is_os_pipe {
WRITE unexpected.txt "should be a script pipe"
}
ASSERT_EQ $info.type "PIPE"
LET $t: STRING = PATH_TYPE("unexpected.txt")
ASSERT_EQ $t "absent"
"#},
},
],
},
CommandMeta {
name: "MUTATION",
syntax: "$var = <expr>",
summary: "Mutate a declared variable.",
description: indoc! {r#"
Reassigns an existing variable, converting the new value to
the type declared at LET time. The explicit annotation is
what authorizes string-to-number conversion here (`$n = "42"`
binds 42 for an INT); a non-numeric string is an error.
Expressions never convert: `"100" + 1` is a Type Error, use
`INT()` / `FLOAT()` to cross that boundary explicitly.
The leading `$` distinguishes mutation from `KEY=value` command
assignments. Assigning an undeclared variable or a mismatched type is
an error.
Mutation writes through to the scope where the variable was
declared, so it survives block exit: `LET $x` outside a block
followed by `$x = ...` inside still reads back the new value
afterwards, for every type. This is the counterpart to LET
shadowing, where `LET $x` *inside* the block declares a
separate inner variable that reverts on exit.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "mutate",
fence_meta: None,
code: indoc! {r#"
# Mutation writes through: the binding holds the new value.
LET $count: INT = 1
$count = 2
ASSERT_EQ $count 2
"#},
},
Example {
name: "convert before math",
fence_meta: None,
code: indoc! {r#"
# Captured output is a string: `"100" + 1` is a Type Error.
# Convert explicitly, then mutate with arithmetic.
IMPORT [STD]
LET $raw: STRING = ECHO 100
LET $n: INT = INT($raw)
$n = $n + 1
# The declared type also converts plain strings on assignment.
$n = "42"
ASSERT_EQ $n 42
# Same crossing for decimals via FLOAT().
LET $frac_str: STRING = ECHO 2.5
LET $f: FLOAT = FLOAT($frac_str) + 0.25
ASSERT_EQ $f 2.75
"#},
},
],
},
CommandMeta {
name: "ASYNC",
syntax: "ASYNC <command...> | ASYNC { <commands> } | LET $var: HANDLE = ASYNC { <commands> }",
summary: "Run steps in a background thread.",
description: indoc! {r#"
Runs a command or block of commands in a background thread with
subshell isolation.
Mutations (ENV, WORKDIR) stay within the block. With `LET`, stores a
task handle for `AWAIT`. Task output streams live to the parent
stdout; a task publishes a value with an explicit `RETURN`,
which `LET $out: TYPE = AWAIT $task` binds.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "async",
fence_meta: None,
code: indoc! {r#"
# Inline and block forms both run in the background; AWAIT joins them.
ASYNC ECHO "warming-up"
LET $a: HANDLE = ASYNC ECHO "first"
LET $b: HANDLE = ASYNC {
ECHO "second"
}
AWAIT $a
AWAIT $b
ASSERT_CONTAINS stdout "first"
ASSERT_CONTAINS stdout "second"
"#},
},
Example {
name: "async task handle",
fence_meta: None,
code: indoc! {r#"
LET $task: HANDLE = ASYNC {
ECHO "built"
}
AWAIT $task
ASSERT_CONTAINS stdout "built"
"#},
},
],
},
CommandMeta {
name: "AWAIT",
syntax: "AWAIT $var | LET $out: STRING = AWAIT $var",
summary: "Join a background task.",
description: indoc! {r#"
Blocks until the named task completes. Propagates errors if the task failed.
Task output streams live during the run; joining binds nothing by
itself. `LET $out: TYPE = AWAIT $var` binds the task's explicit
`RETURN` value instead, or `INT` 0 when the task succeeded
without one (add `RETURN <expr>` to the task body to yield
a value).
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "await",
fence_meta: None,
code: indoc! {r#"
LET $task: HANDLE = ASYNC ECHO "done"
AWAIT $task
ASSERT_CONTAINS stdout "done"
"#},
},
Example {
name: "await capture",
fence_meta: None,
code: indoc! {r#"
LET $task: HANDLE = ASYNC {
ECHO "logged"
RETURN "returned"
}
# AWAIT binds the RETURN value, not the streamed output.
LET $out: STRING = AWAIT $task
ASSERT_EQ $out "returned"
"#},
},
],
},
CommandMeta {
name: "CANCEL",
syntax: "CANCEL $var",
summary: "Synchronously cancel a background task.",
description: indoc! {r#"
Kills the named background task spawned via LET $var: HANDLE = ASYNC ....
Blocking: returns only after the task thread has been joined and its OS
process reaped, so no residual filesystem or stream mutation follows. A
later AWAIT $var reports cancellation. Only named tasks can be cancelled.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "cancel",
fence_meta: None,
code: indoc! {r#"
LET $task: HANDLE = ASYNC SLEEP 30s
CANCEL $task
"#},
},
Example {
name: "await after cancel reports cancellation",
fence_meta: Some("expect_error:\"was cancelled\""),
code: indoc! {r#"
# A cancelled task stays cancelled: joining it reports.
LET $task: HANDLE = ASYNC SLEEP 30s
CANCEL $task
AWAIT $task
"#},
},
],
},
CommandMeta {
name: "TIMEOUT",
syntax: "TIMEOUT <duration> <command...> | TIMEOUT <duration> { <commands> } | TIMEOUT <duration> AWAIT $var",
summary: "Enforce an execution deadline.",
description: indoc! {r#"
Aborts the wrapped step or block with a deadline error if it exceeds the
duration (e.g. 500ms, 10s, 2m; a bare number means seconds).
A blocking foreground process is killed.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "timeout",
fence_meta: None,
code: indoc! {r#"
TIMEOUT 30s WRITE heartbeat.txt alive
LET $beat: STRING = READ heartbeat.txt
ASSERT_EQ $beat "alive"
"#},
},
Example {
name: "timeout block",
fence_meta: None,
code: indoc! {r#"
TIMEOUT 30s {
WRITE a.txt one
WRITE b.txt two
}
LET $a: STRING = READ a.txt
LET $b: STRING = READ b.txt
ASSERT_EQ $a "one"
ASSERT_EQ $b "two"
"#},
},
Example {
name: "deadline aborts the step",
fence_meta: Some("expect_error:\"TIMEOUT after\""),
code: indoc! {r#"
# 50ms expires long before the sleep does: the step dies
# with a deadline error instead of running out the clock.
TIMEOUT 50ms SLEEP 30s
"#},
},
Example {
name: "timeout variable duration",
fence_meta: None,
code: indoc! {r#"
# Durations resolve at runtime, so variables work too.
LET $budget: DURATION = "30s"
TIMEOUT $budget WRITE heartbeat.txt alive
LET $beat: STRING = READ heartbeat.txt
ASSERT_EQ $beat "alive"
"#},
},
],
},
CommandMeta {
name: "FUNC",
syntax: "FUNC NAME([$param: TYPE, ...]) { <commands> }",
summary: "Define a user function.",
description: indoc! {r#"
Defines a user function with UPPERCASE name and explicitly typed
parameters.
Params bind by position, converting each argument to its
declared parameter type before the body runs.
Bodies run in a fresh variable scope; LETs inside do not leak. A nested
FUNC definition is scoped to its block and reverts on exit. Names share
one namespace with native and host-registered functions, which a FUNC
may never shadow.
Functions resolve like variables: a name is visible from its
definition line, so recursion works but mutual recursion does
not (the second name does not exist while the first body
lowers). Calls name their module (`STD::GLOB(...)`) unless
imported; see IMPORT.
Invoke any function with one syntax: `NAME(...)` as a statement
(discarding the value) or `LET $var: TYPE = NAME(...)` to capture
the RETURN value (fallthrough without RETURN captures as "").
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[
Example {
name: "func def call",
fence_meta: None,
code: indoc! {r#"
FUNC GREET($name: STRING) {
RETURN $name
}
LET $res: STRING = GREET("ada")
ASSERT_EQ $res "ada"
# Statement form: parens stay, the value drops.
GREET("bex")
"#},
},
Example {
name: "call with pipes",
fence_meta: None,
code: indoc! {r#"
# A pipe handle travels into a function as a typed argument
# and is usable as a binding target in both directions.
# `LET $p: PIPE` mints the handle; `$p` passes it on.
FUNC DRAIN($q: PIPE) {
WITH_IO [stdin=$q] READ_LINE $line
RETURN $line
}
LET $p: PIPE
WITH_IO [stdout=$p] ECHO "payload"
LET $got: STRING = DRAIN($p)
ASSERT_EQ $got "payload"
"#},
},
],
},
CommandMeta {
name: "RETURN",
syntax: "RETURN [<expr>]",
summary: "Return a value from a function, task, or inline block.",
description: indoc! {r#"
Ends the nearest enclosing boundary with a value: a function
call, an `ASYNC` task (bound by `LET $o = AWAIT $t`), or an
inline `LET` block. Bare `RETURN` with no expression yields
`""`.
Falling off the end without RETURN yields "". RETURN with no
enclosing boundary (including at top level) is an error; use
EXIT or ECHO there.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[Example {
name: "return",
fence_meta: None,
code: indoc! {r#"
FUNC PICK($flag: BOOL) {
IF $flag {
RETURN "yes"
}
RETURN "no"
}
LET $res: STRING = PICK(true)
ASSERT_EQ $res "yes"
# Fallthrough without RETURN yields its own value.
LET $no: STRING = PICK(false)
ASSERT_EQ $no "no"
"#},
}],
},
CommandMeta {
name: "WHILE",
syntax: "WHILE <bool-expr> { <commands> }",
summary: "Loop while a condition holds.",
description: indoc! {r#"
Re-evaluates a Bool condition each iteration (same is_truthy rule as IF;
non-Bool is a type error).
Each iteration runs in a fresh scope; mutate outer state with $var = ...
so the next check observes it. BREAK exits the loop; CONTINUE skips to
the next check.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[Example {
name: "while loop",
fence_meta: None,
code: indoc! {r#"
# The condition re-evaluates every iteration: three passes, then stop.
LET $n: INT = 0
WHILE $n < 3 {
WRITE tick.txt "{{ $n }}"
$n = $n + 1
}
ASSERT_EQ $n 3
LET $tick: STRING = READ tick.txt
ASSERT_EQ $tick "2"
"#},
}],
},
CommandMeta {
name: "BREAK",
syntax: "BREAK",
summary: "Exit the innermost loop.",
description: indoc! {r#"
Exits the innermost enclosing FOR or WHILE loop.
BREAK outside a loop, or across a FUNC or ASYNC boundary, is an error.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[Example {
name: "break",
fence_meta: None,
code: indoc! {r#"
# BREAK leaves after the first pass: only "a" is written.
FOR $x: STRING IN ["a", "b"] {
WRITE picked.txt "{{ $x }}"
BREAK
}
LET $body: STRING = READ picked.txt
ASSERT_EQ $body "a"
"#},
}],
},
CommandMeta {
name: "CONTINUE",
syntax: "CONTINUE",
summary: "Skip to the next loop iteration.",
description: indoc! {r#"
Skips the rest of the innermost enclosing FOR or WHILE body and starts
the next iteration.
CONTINUE outside a loop, or across a FUNC or ASYNC boundary, is an error.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[Example {
name: "continue",
fence_meta: None,
code: indoc! {r#"
# CONTINUE skips the write on "a": only "b" lands.
FOR $x: STRING IN ["a", "b"] {
IF $x == "a" {
CONTINUE
}
WRITE picked.txt "{{ $x }}"
}
LET $body: STRING = READ picked.txt
ASSERT_EQ $body "b"
"#},
}],
},
CommandMeta {
name: KEYWORD_IMPORT,
syntax: "IMPORT [<module>, ...] | IMPORT <module>",
summary: "Bring module functions into bare-call scope.",
description: indoc! {r#"
Every function call names its module (`STD::GLOB(...)`,
`MOCK::READ_CSV(...)`) unless the module is imported:
`IMPORT [STD]` lets the rest of the scope call `GLOB(...)`
bare. Calls resolve at parse time against `SCRIPT`
definitions first, then imported modules; unknown modules,
unknown functions, and unimported bare calls are parse
errors, never runtime surprises.
IMPORT is a lowering directive, not a step: it applies from
its line to the enclosing block exit, then reverts, exactly
like `LET` scoping but with no runtime footprint. Guards do
not apply to it. Two imported modules exporting one name is
an ambiguity error: qualify the call instead.
`EXPORT` is reserved for future script-module support and
cannot be used yet.
"#},
args: &[],
flags: &[],
default_output: None,
examples: &[Example {
name: "import",
fence_meta: None,
code: indoc! {r#"
# Calls name their module (STD::GLOB); IMPORT [STD] drops the prefix.
WRITE a.txt "hi \{{ env:WHO }}!"
IMPORT [STD]
FOR $x: STRING IN GLOB("*.txt") { EXPAND $x WHO=World }
ASSERT_CONTAINS stdout "hi World!"
"#},
}],
},
]
}
impl fmt::Display for StepKind {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
StepKind::InheritEnv { keys } => write!(f, "INHERIT_ENV [{}]", keys.join(", ")),
StepKind::Workdir(a) => write!(f, "WORKDIR {}", fmt_value(a, quote_arg)),
StepKind::Workspace(t) => write!(f, "WORKSPACE {}", t),
StepKind::Env { key, value } => {
write!(f, "ENV {}={}", key, fmt_value(value, quote_arg))
}
StepKind::Run(c) => write!(f, "RUN {}", fmt_value(c, quote_run)),
StepKind::RunExec { argv } => {
let parts: Vec<String> = argv.iter().map(fmt_exec_arg).collect();
write!(f, "RUN [{}]", parts.join(", "))
}
StepKind::Echo(m) => write!(f, "ECHO {}", fmt_value(m, quote_msg)),
StepKind::Copy {
from_workspace,
from,
to,
} => {
if let Some(target) = from_workspace {
write!(
f,
"COPY --from-workspace {} {} {}",
target,
fmt_value(from, quote_arg),
fmt_value(to, quote_arg)
)
} else {
write!(
f,
"COPY {} {}",
fmt_value(from, quote_arg),
fmt_value(to, quote_arg)
)
}
}
StepKind::Symlink {
from_workspace,
from,
to,
} => {
if let Some(target) = from_workspace {
write!(
f,
"SYMLINK --from-workspace {} {} {}",
target,
fmt_value(from, quote_arg),
fmt_value(to, quote_arg)
)
} else {
write!(
f,
"SYMLINK {} {}",
fmt_value(from, quote_arg),
fmt_value(to, quote_arg)
)
}
}
StepKind::Mkdir(a) => write!(f, "MKDIR {}", fmt_value(a, quote_arg)),
StepKind::Ls(a) => {
write!(f, "LS")?;
if let Some(x) = a {
write!(f, " {}", fmt_value(x, quote_arg))?;
}
Ok(())
}
StepKind::Cwd => write!(f, "CWD"),
StepKind::Read(a) => {
write!(f, "READ")?;
if let Some(x) = a {
write!(f, " {}", fmt_value(x, quote_arg))?;
}
Ok(())
}
StepKind::ReadLine { var } => write!(f, "READ_LINE ${}", var),
StepKind::Write { path, contents } => {
write!(f, "WRITE {}", fmt_value(path, quote_arg))?;
if let Some(b) = contents {
write!(f, " {}", fmt_value(b, quote_msg))?;
}
Ok(())
}
StepKind::Append { path, contents } => {
write!(f, "APPEND {}", fmt_value(path, quote_arg))?;
if let Some(b) = contents {
write!(f, " {}", fmt_value(b, quote_msg))?;
}
Ok(())
}
StepKind::Expand { path, overrides } => {
write!(f, "EXPAND")?;
if let Some(p) = path {
write!(f, " {}", fmt_value(p, quote_arg))?;
}
for (k, v) in overrides {
write!(f, " {}={}", k, fmt_value(v, quote_arg))?;
}
Ok(())
}
StepKind::AssertEq {
hash,
actual,
expected,
} => {
if let Some(d) = hash {
write!(f, "ASSERT_EQ --hash {d} {}", fmt_assert_target(actual))?;
} else {
write!(
f,
"ASSERT_EQ {} {}",
fmt_assert_target(actual),
fmt_value(
expected
.as_ref()
.expect("Display of ASSERT_EQ without --hash needs expected"),
quote_msg
)
)?;
}
Ok(())
}
StepKind::AssertContains { haystack, needle } => write!(
f,
"ASSERT_CONTAINS {} {}",
fmt_assert_target(haystack),
fmt_value(needle, quote_msg)
),
StepKind::WithIo { bindings, cmd } => {
let p: Vec<String> = bindings.iter().map(fmt_io).collect();
write!(f, "WITH_IO [{}] {}", p.join(", "), cmd)
}
StepKind::WithIoBlock { bindings } => {
let p: Vec<String> = bindings.iter().map(fmt_io).collect();
write!(f, "WITH_IO [{}] {{...}}", p.join(", "))
}
StepKind::CopyGit {
rev,
from,
to,
include_dirty,
} => {
if *include_dirty {
write!(
f,
"COPY_GIT --include-dirty {} {} {}",
fmt_value(rev, quote_arg),
fmt_value(from, quote_arg),
fmt_value(to, quote_arg)
)
} else {
write!(
f,
"COPY_GIT {} {} {}",
fmt_value(rev, quote_arg),
fmt_value(from, quote_arg),
fmt_value(to, quote_arg)
)
}
}
StepKind::HashSha256 { path } => {
write!(f, "HASH_SHA256 {}", fmt_value(path, quote_arg))
}
StepKind::Exit(code) => write!(f, "EXIT {}", fmt_raw_arg(code)),
StepKind::Sleep { duration } => write!(f, "SLEEP {}", fmt_raw_arg(duration)),
StepKind::ListAppend { list, item } => {
write!(f, "LIST_APPEND ${} {}", list, fmt_raw_arg(item))
}
StepKind::For {
key_var,
key_type,
var,
var_type,
in_expr,
body,
} => {
match key_var {
Some(k) => {
let kt = key_type.as_deref().unwrap_or("STRING");
write!(
f,
"FOR ${}: {}, ${}: {} IN {} {{",
k, kt, var, var_type, in_expr
)?
}
None => write!(f, "FOR ${}: {} IN {} {{", var, var_type, in_expr)?,
}
for s in body {
write!(f, "\n {}", s)?;
}
write!(f, "\n}}")
}
StepKind::If {
cond,
then_body,
else_ifs,
else_body,
} => {
write!(f, "IF {} {{", cond)?;
for s in then_body {
write!(f, "\n {}", s)?;
}
write!(f, " }}")?;
for (c, b) in else_ifs {
write!(f, " ELSE IF {} {{", c)?;
for s in b {
write!(f, "\n {}", s)?;
}
write!(f, " }}")?;
}
if let Some(b) = else_body {
write!(f, " ELSE {{")?;
for s in b {
write!(f, "\n {}", s)?;
}
write!(f, " }}")?;
}
Ok(())
}
StepKind::Assign {
var,
decl_type,
expr,
} => {
if matches!(expr, Expr::FreshPipe) {
write!(f, "LET ${}: {}", var, decl_type)
} else {
write!(f, "LET ${}: {} = {}", var, decl_type, expr)
}
}
StepKind::Set { var, expr } => write!(f, "${} = {}", var, expr),
StepKind::AssignCapture {
var,
decl_type,
cmd,
} => {
write!(f, "LET ${}: {} = {}", var, decl_type, cmd)
}
StepKind::AsyncBlock { body } => {
write!(f, "ASYNC {{")?;
for s in body {
write!(f, "\n {}", s)?;
}
write!(f, "\n}}")
}
StepKind::AssignAsync {
var,
decl_type,
body,
} => {
write!(f, "LET ${}: {} = ASYNC {{", var, decl_type)?;
for s in body {
write!(f, "\n {}", s)?;
}
write!(f, "\n}}")
}
StepKind::Await { var } => write!(f, "AWAIT ${}", var),
StepKind::AwaitCapture {
out_var,
out_type,
task_var,
} => {
write!(f, "LET ${}: {} = AWAIT ${}", out_var, out_type, task_var)
}
StepKind::Cancel { var } => write!(f, "CANCEL ${}", var),
StepKind::Timeout { duration, body } => {
let budget = fmt_raw_arg(duration);
if body.len() == 1 {
write!(f, "TIMEOUT {} {}", budget, body[0].kind)
} else {
write!(f, "TIMEOUT {} {{", budget)?;
for s in body {
write!(f, "\n {}", s)?;
}
write!(f, "\n}}")
}
}
StepKind::FuncDef { name, params, body } => {
let ps: Vec<String> = params
.iter()
.map(|(p, t)| format!("${}: {}", p, t))
.collect();
write!(f, "FUNC {}({}) {{", name, ps.join(", "))?;
for s in body {
write!(f, "\n {}", s)?;
}
write!(f, "\n}}")
}
StepKind::Call { name, args } => {
let ps: Vec<String> = args.iter().map(|a| format!("{}", a)).collect();
write!(f, "{}({})", name, ps.join(", "))
}
StepKind::Return { expr } => write!(f, "RETURN {}", expr),
StepKind::While { cond, body } => {
write!(f, "WHILE {} {{", cond)?;
for s in body {
write!(f, "\n {}", s)?;
}
write!(f, "\n}}")
}
StepKind::Break => write!(f, "BREAK"),
StepKind::Continue => write!(f, "CONTINUE"),
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::command::{format_duration, parse_duration};
use crate::parser::parse_script;
fn parse_err(script: &str) -> String {
parse_script(script, lower_command)
.expect_err("script must fail to parse")
.to_string()
}
#[test]
fn malformed_with_io_binding_names_the_bad_binding() {
let err = parse_err("WITH_IO [stdout=discard] ECHO \"test\"\n");
assert!(err.contains("invalid syntax for command WITH_IO"), "{err}");
assert!(!err.contains("unknown command"), "{err}");
assert!(err.contains("stdout=discard"), "{err}");
assert!(err.contains("[stdout=$p]"), "{err}");
}
#[test]
fn connect_is_unknown_command() {
let err = parse_err("CONNECT 127.0.0.1:8080\n");
assert!(err.contains("unknown command"), "{err}");
assert!(err.contains("CONNECT"), "{err}");
}
#[test]
fn listen_is_unknown_command() {
let err = parse_err("LISTEN 127.0.0.1:8080\n");
assert!(err.contains("unknown command"), "{err}");
assert!(err.contains("LISTEN"), "{err}");
}
#[test]
fn await_without_task_variable_points_at_syntax() {
let err = parse_err("AWAIT ECHO \"test\"\n");
assert!(err.contains("invalid syntax for command AWAIT"), "{err}");
assert!(!err.contains("unknown command"), "{err}");
assert!(err.contains("AWAIT $t"), "{err}");
assert!(err.contains("ECHO"), "{err}");
}
#[test]
fn bare_let_without_type_points_at_typed_syntax() {
let err = parse_err("LET $x = 1\n");
assert!(err.contains("invalid syntax for command LET"), "{err}");
assert!(err.contains("LET $name: STRING = <expr>"), "{err}");
}
#[test]
fn workspace_accepts_all_four_targets_uppercase_only() {
for (spelling, target) in [
("SNAPSHOT", WorkspaceTarget::Snapshot),
("LOCAL", WorkspaceTarget::Local),
("CACHE", WorkspaceTarget::Cache { local: false }),
("SYSTEM", WorkspaceTarget::System),
] {
let steps =
parse_script(&format!("WORKSPACE {spelling}\n"), lower_command).expect("parses");
assert_eq!(steps.len(), 1);
assert_eq!(steps[0].kind, StepKind::Workspace(target.clone()));
assert_eq!(steps[0].kind.to_string(), format!("WORKSPACE {target}"));
}
for spelling in ["snapshot", "local", "cache", "system"] {
let err = parse_err(&format!("WORKSPACE {spelling}\n"));
assert!(
err.contains("expected one of SNAPSHOT|LOCAL|CACHE|SYSTEM"),
"{spelling}: {err}"
);
}
let err = parse_err("WORKSPACE REMOTE\n");
assert!(
err.contains("expected one of SNAPSHOT|LOCAL|CACHE|SYSTEM"),
"{err}"
);
let steps = parse_script("WORKSPACE CACHE --local\n", lower_command).expect("parses");
assert_eq!(
steps[0].kind,
StepKind::Workspace(WorkspaceTarget::Cache { local: true })
);
assert_eq!(steps[0].kind.to_string(), "WORKSPACE CACHE --local");
for bad in [
"WORKSPACE SNAPSHOT --local\n",
"WORKSPACE LOCAL --local\n",
"WORKSPACE SYSTEM --local\n",
] {
let err = parse_err(bad);
assert!(err.contains("--local requires CACHE"), "{bad}: {err}");
}
}
#[test]
fn copy_from_workspace_selects_source_root() {
for (spelling, target) in [
("SNAPSHOT", WorkspaceTarget::Snapshot),
("LOCAL", WorkspaceTarget::Local),
("CACHE", WorkspaceTarget::Cache { local: false }),
("SYSTEM", WorkspaceTarget::System),
] {
let steps = parse_script(
&format!("COPY --from-workspace {spelling} a.txt b.txt\n"),
lower_command,
)
.expect("parses");
assert!(
matches!(&steps[0].kind, StepKind::Copy { from_workspace: Some(t), .. } if *t == target),
"unexpected lowering for {spelling}: {:?}",
steps[0].kind
);
}
for script in [
"COPY --from-workspace=CACHE a.txt b.txt\n",
"COPY --from-workspace=\"CACHE\" a.txt b.txt\n",
] {
let steps = parse_script(script, lower_command).expect("parses");
assert!(
matches!(
&steps[0].kind,
StepKind::Copy {
from_workspace: Some(WorkspaceTarget::Cache { local: false }),
..
}
),
"unexpected lowering for {script:?}: {:?}",
steps[0].kind
);
}
let steps = parse_script("COPY a.txt b.txt\n", lower_command).expect("parses");
assert!(
matches!(
&steps[0].kind,
StepKind::Copy {
from_workspace: None,
..
}
),
"unexpected lowering: {:?}",
steps[0].kind
);
for bad in ["REMOTE", "local"] {
let err = parse_err(&format!("COPY --from-workspace {bad} a.txt b.txt\n"));
assert!(err.contains("unknown workspace source"), "{bad}: {err}");
}
}
#[test]
fn symlink_from_workspace_selects_source_root() {
for (spelling, target) in [
("SNAPSHOT", WorkspaceTarget::Snapshot),
("LOCAL", WorkspaceTarget::Local),
("CACHE", WorkspaceTarget::Cache { local: false }),
("SYSTEM", WorkspaceTarget::System),
] {
let steps = parse_script(
&format!("SYMLINK --from-workspace {spelling} a.txt b.txt\n"),
lower_command,
)
.expect("parses");
assert!(
matches!(&steps[0].kind, StepKind::Symlink { from_workspace: Some(t), .. } if *t == target),
"unexpected lowering for {spelling}: {:?}",
steps[0].kind
);
let roundtrip = steps[0].kind.to_string();
assert!(
roundtrip.contains("--from-workspace"),
"display should round-trip the flag: {roundtrip}"
);
}
let steps = parse_script("SYMLINK a.txt b.txt\n", lower_command).expect("parses");
assert!(
matches!(
&steps[0].kind,
StepKind::Symlink {
from_workspace: None,
..
}
),
"unexpected lowering: {:?}",
steps[0].kind
);
for bad in ["REMOTE", "local"] {
let err = parse_err(&format!("SYMLINK --from-workspace {bad} a.txt b.txt\n"));
assert!(err.contains("unknown workspace source"), "{bad}: {err}");
}
let steps = parse_script(
"SYMLINK --from-workspace=LOCAL a.txt b.txt\n",
lower_command,
)
.expect("parses");
assert!(
matches!(
&steps[0].kind,
StepKind::Symlink {
from_workspace: Some(WorkspaceTarget::Local),
..
}
),
"unexpected lowering: {:?}",
steps[0].kind
);
}
#[test]
fn dash_dash_equals_tokens_bypass_assignment() {
let steps = parse_script("ENV --foo=bar\n", lower_command).expect("parses");
let StepKind::Env { key, value } = &steps[0].kind else {
panic!("expected Env, got {:?}", steps[0].kind);
};
assert_eq!(key, "--foo");
assert_eq!(value.as_str(), "bar");
let steps = parse_script("RUN echo --foo=bar\n", lower_command).expect("parses");
let StepKind::Run(cmd) = &steps[0].kind else {
panic!("expected Run, got {:?}", steps[0].kind);
};
assert!(
cmd.as_str().contains("--foo=bar"),
"unexpected RUN lowering: {cmd:?}"
);
let digest = "08135c1b6349b0e4f894c36221952f0de00e6b4d82f80895abf359755e77103c";
let steps = parse_script(&format!("ASSERT_EQ --hash={digest} $body\n"), lower_command)
.expect("parses");
let StepKind::AssertEq { hash, .. } = &steps[0].kind else {
panic!("expected AssertEq, got {:?}", steps[0].kind);
};
assert_eq!(hash.as_deref(), Some(digest));
let steps = parse_script("EXPAND --k=v\n", lower_command).expect("parses");
let StepKind::Expand { path, overrides } = &steps[0].kind else {
panic!("expected Expand, got {:?}", steps[0].kind);
};
assert!(path.is_none());
assert_eq!(overrides.len(), 1);
assert_eq!(overrides[0].0.as_str(), "--k");
}
#[test]
fn space_before_paren_is_not_a_call() {
let steps = parse_script("ECHO (1 + 2)\n", lower_command).expect("parses");
assert_eq!(steps.len(), 1);
assert!(
!matches!(steps[0].kind, crate::ast::StepKind::Call { .. }),
"space before paren must not route to a call: {:?}",
steps[0].kind
);
}
#[test]
fn unknown_type_tag_parses_as_custom() {
let steps = parse_script("LET $x: FOO = 1\n", lower_command).expect("custom tag parses");
let StepKind::Assign { decl_type, .. } = &steps[0].kind else {
panic!("expected Assign, got {:?}", steps[0].kind);
};
assert_eq!(decl_type, "FOO");
}
#[test]
fn bare_for_without_types_is_rejected() {
let err = parse_err("FOR $i IN [1] { ECHO hi }\n");
assert!(err.contains("FOR requires explicit types"), "{err}");
}
#[test]
fn mutate_statement_parses_without_keyword() {
let steps = parse_script("$y = 2\n", lower_command).expect("mutation parses");
assert!(matches!(steps[0].kind, StepKind::Set { .. }));
}
#[test]
fn set_keyword_is_rejected_with_mutation_hint() {
let err = parse_err("SET $y = 2\n");
assert!(err.contains("not a keyword"), "{err}");
assert!(err.contains("$var = <expr>"), "{err}");
}
#[test]
fn structural_fallthrough_commits_per_keyword() {
for (script, cmd) in [
("CANCEL foo\n", "CANCEL"),
("TIMEOUT foo\n", "TIMEOUT"),
("FOR foo\n", "FOR"),
("IF foo\n", "IF"),
("LET foo\n", "LET"),
("ASYNC\n", "ASYNC"),
("ELSE foo\n", "ELSE"),
] {
let err = parse_err(script);
assert!(
err.contains(&format!("invalid syntax for command {cmd}")),
"{cmd}: {err}"
);
assert!(!err.contains("unknown command"), "{cmd}: {err}");
}
}
#[test]
fn leaf_arity_errors_carry_invalid_syntax_prefix() {
let err = parse_err("SLEEP 1s 2s\n");
assert!(err.contains("invalid syntax for command SLEEP"), "{err}");
assert!(!err.contains("unknown command"), "{err}");
}
#[test]
fn list_append_lowers_variable_and_item() {
let steps = parse_script("LIST_APPEND $items \"hi\"\n", lower_command).expect("parses");
let StepKind::ListAppend { list, item } = &steps[0].kind else {
panic!("expected ListAppend, got {:?}", steps[0].kind);
};
assert_eq!(list, "items");
assert!(matches!(item, Arg::String(s, _) if s == "hi"));
assert_eq!(steps[0].kind.to_string(), "LIST_APPEND $items \"hi\"");
}
#[test]
fn list_append_rejects_wrong_arity() {
for script in [
"LIST_APPEND\n",
"LIST_APPEND $items\n",
"LIST_APPEND $items \"a\" \"b\"\n",
] {
let err = parse_err(script);
assert!(
err.contains("invalid syntax for command LIST_APPEND"),
"{script}: {err}"
);
assert!(!err.contains("unknown command"), "{script}: {err}");
}
}
#[test]
fn list_append_rejects_non_variable_target() {
let err = parse_err("LIST_APPEND items \"a\"\n");
assert!(
err.contains("invalid syntax for command LIST_APPEND"),
"{err}"
);
assert!(!err.contains("unknown command"), "{err}");
}
#[test]
fn read_line_rejects_bare_word_target() {
let err = parse_err("READ_LINE reply\n");
assert!(err.contains("READ_LINE requires a $variable"), "{err}");
assert!(!err.contains("unknown command"), "{err}");
}
#[test]
fn genuinely_unknown_command_keeps_bare_message() {
let err = parse_err("FROBNICATE hi\n");
assert!(err.contains("unknown command: FROBNICATE"), "{err}");
assert!(!err.contains("did you mean"), "{err}");
}
#[test]
fn lowercase_command_suggests_uppercase() {
let err = lower_command("echo", vec![Arg::String("hi".to_string(), false)])
.expect_err("must fail")
.to_string();
assert!(err.contains("unknown command: echo"), "{err}");
assert!(err.contains("did you mean `ECHO`"), "{err}");
}
#[test]
fn func_def_requires_typed_uppercase_name() {
let steps = parse_script(
"FUNC GREET($name: STRING) {\n RETURN $name\n}\n",
lower_command,
)
.expect("func def parses");
let StepKind::FuncDef { name, params, body } = &steps[0].kind else {
panic!("expected FuncDef, got {:?}", steps[0].kind);
};
assert_eq!(name, "GREET");
assert_eq!(
params,
&vec![("name".to_string(), "STRING".to_string())],
"{params:?}"
);
assert!(matches!(body[0].kind, StepKind::Return { .. }));
}
#[test]
fn lowercase_func_name_is_rejected() {
let err = parse_err("FUNC greet($x: STRING) {\n RETURN $x\n}\n");
assert!(err.contains("FUNC"), "{err}");
}
#[test]
fn call_and_while_lower_correctly() {
let steps = parse_script(
"FUNC GREET($name: STRING) {\n RETURN $name\n}\nGREET(\"ada\")\n",
lower_command,
)
.expect("call parses");
assert!(
matches!(&steps[1].kind, StepKind::Call { name, .. } if name == "SCRIPT::GREET"),
"{:?}",
steps[1].kind
);
let steps = parse_script(
"FUNC GREET($a: STRING, $b: STRING) {\n RETURN $a\n}\nGREET(\"ada\", \"bex\")\n",
lower_command,
)
.expect("spaced call parses");
assert!(
matches!(&steps[1].kind, StepKind::Call { name, args } if name == "SCRIPT::GREET" && args.len() == 2),
"{:?}",
steps[1].kind
);
let steps = parse_script(
indoc! {r#"
WHILE !$done {
BREAK
}
"#},
lower_command,
)
.expect("while parses");
let StepKind::While { body, .. } = &steps[0].kind else {
panic!("expected While, got {:?}", steps[0].kind);
};
assert!(matches!(body[0].kind, StepKind::Break));
}
#[test]
fn let_capture_call_and_async_call_lower() {
let steps = parse_script(
indoc! {r#"
FUNC GREET($name: STRING) {
RETURN $name
}
LET $r: STRING = GREET("ada")
"#},
lower_command,
)
.expect("capture call parses");
let StepKind::Assign { var, expr, .. } = &steps[1].kind else {
panic!("expected Assign, got {:?}", steps[1].kind);
};
assert_eq!(var, "r");
assert!(
matches!(expr, Expr::Call { name, .. } if name == "SCRIPT::GREET"),
"{expr:?}"
);
let steps = parse_script(
"FUNC GREET($name: STRING) {\n RETURN $name\n}\nLET $t: HANDLE = ASYNC GREET(\"a\")\n",
lower_command,
)
.expect("async call parses");
assert!(
matches!(&steps[1].kind, StepKind::AssignAsync { .. }),
"{:?}",
steps[1].kind
);
}
#[test]
fn multiline_call_args_span_lines() {
let steps = parse_script(
"FUNC SERVE($b: STRING, $u: STRING, $p: STRING, $o: MAP) {\n RETURN $b\n}\nLET $m: MAP = SERVE(\n \"127.0.0.1:2241\",\n \"test\",\n \"test123\", {\n key_path: \"test_key\"\n }\n)\n",
lower_command,
)
.expect("multiline call parses");
let StepKind::Assign { expr, .. } = &steps[1].kind else {
panic!("expected Assign, got {:?}", steps[1].kind);
};
let Expr::Call { name, args } = expr else {
panic!("expected Call expr, got {expr:?}");
};
assert_eq!(name, "SCRIPT::SERVE");
assert_eq!(args.len(), 4);
assert!(matches!(&args[3], Expr::Map(entries) if entries.len() == 1));
let rendered = steps[1].to_string();
assert!(!rendered.contains('\n'), "{rendered}");
let script = "FUNC SERVE($b: STRING, $u: STRING, $p: STRING, $o: MAP) {\n RETURN $b\n}\nLET $m: MAP = SERVE(\n \"127.0.0.1:2241\",\n \"test\",\n \"test123\", {\n key_path: \"test_key\"\n }\n)\n";
let again = parse_script(script, lower_command).expect("reparse ok");
assert_eq!(again, steps);
}
#[test]
fn multiline_bare_call_and_list_span_lines() {
let steps = parse_script(
indoc! {r#"
FUNC GREET($a: STRING) {
RETURN $a
}
GREET(
"ada"
)
"#},
lower_command,
)
.expect("multiline bare call parses");
let StepKind::Call { name, args } = &steps[1].kind else {
panic!("expected Call, got {:?}", steps[1].kind);
};
assert_eq!(name, "SCRIPT::GREET");
assert_eq!(args.len(), 1);
let steps = parse_script(
indoc! {r#"
LET $l: LIST = [
"a",
"b"
]
"#},
lower_command,
)
.expect("multiline list parses");
let StepKind::Assign { expr, .. } = &steps[0].kind else {
panic!("expected Assign, got {:?}", steps[0].kind);
};
assert!(
matches!(expr, Expr::List(items) if items.len() == 2),
"{expr:?}"
);
}
#[test]
fn parse_duration_units() {
use std::time::Duration;
assert_eq!(parse_duration("500ms").unwrap(), Duration::from_millis(500));
assert_eq!(parse_duration("10s").unwrap(), Duration::from_secs(10));
assert_eq!(parse_duration("2m").unwrap(), Duration::from_secs(120));
assert_eq!(parse_duration("1h").unwrap(), Duration::from_secs(3600));
assert_eq!(parse_duration("30").unwrap(), Duration::from_secs(30));
}
#[test]
fn parse_duration_rejects_garbage() {
assert!(parse_duration("").is_err());
assert!(parse_duration("banana").is_err());
assert!(parse_duration("10x").is_err());
assert!(parse_duration("0s").is_err());
assert!(parse_duration("0").is_err());
assert!(parse_duration("-5s").is_err());
}
#[test]
fn format_duration_round_trips() {
for text in ["500ms", "10s", "2m", "1h", "90s", "1500ms"] {
let parsed = parse_duration(text).unwrap();
let rendered = format_duration(&parsed);
assert_eq!(
parse_duration(&rendered).unwrap(),
parsed,
"round-trip failed for {text}"
);
}
assert_eq!(format_duration(&parse_duration("90s").unwrap()), "90s");
assert_eq!(format_duration(&parse_duration("2m").unwrap()), "2m");
}
#[test]
fn structural_metadata_covers_all_structural_kinds() {
use crate::ast::Value;
fn metadata_name(kind: &StepKind) -> Option<&'static str> {
match kind {
StepKind::WithIo { .. } | StepKind::WithIoBlock { .. } => Some("WITH_IO"),
StepKind::For { .. } => Some("FOR"),
StepKind::If { .. } => Some("IF"),
StepKind::Assign { .. } => Some("LET"),
StepKind::Set { .. } => Some("MUTATION"),
StepKind::AssignCapture { .. } => Some("LET"),
StepKind::AwaitCapture { .. } => Some("AWAIT"),
StepKind::AsyncBlock { .. } | StepKind::AssignAsync { .. } => Some("ASYNC"),
StepKind::Await { .. } => Some("AWAIT"),
StepKind::Cancel { .. } => Some("CANCEL"),
StepKind::Timeout { .. } => Some("TIMEOUT"),
StepKind::FuncDef { .. } => Some("FUNC"),
StepKind::Call { .. } => None,
StepKind::Return { .. } => Some("RETURN"),
StepKind::While { .. } => Some("WHILE"),
StepKind::Break => Some("BREAK"),
StepKind::Continue => Some("CONTINUE"),
StepKind::RunExec { .. } => None,
StepKind::Workdir(_)
| StepKind::Workspace(_)
| StepKind::Env { .. }
| StepKind::InheritEnv { .. }
| StepKind::Run(_)
| StepKind::Echo(_)
| StepKind::Copy { .. }
| StepKind::Symlink { .. }
| StepKind::Mkdir(_)
| StepKind::Ls(_)
| StepKind::Cwd
| StepKind::Read(_)
| StepKind::ReadLine { .. }
| StepKind::Write { .. }
| StepKind::Append { .. }
| StepKind::Expand { .. }
| StepKind::AssertEq { .. }
| StepKind::AssertContains { .. }
| StepKind::CopyGit { .. }
| StepKind::HashSha256 { .. }
| StepKind::Exit(_)
| StepKind::Sleep { .. }
| StepKind::ListAppend { .. } => None,
}
}
let dummies: Vec<StepKind> = vec![
StepKind::WithIo {
bindings: Vec::new(),
cmd: Box::new(StepKind::Echo(crate::ast::Arg::String(
"x".to_string(),
false,
))),
},
StepKind::For {
key_var: None,
key_type: None,
var: "i".to_string(),
var_type: "STRING".to_string(),
in_expr: Expr::Literal(Value::bool(true)),
body: Vec::new(),
},
StepKind::If {
cond: Box::new(Expr::Literal(Value::bool(true))),
then_body: Vec::new(),
else_ifs: Vec::new(),
else_body: None,
},
StepKind::Assign {
var: "v".to_string(),
decl_type: "BOOL".to_string(),
expr: Expr::Literal(Value::bool(true)),
},
StepKind::Set {
var: "v".to_string(),
expr: Expr::Literal(Value::bool(true)),
},
StepKind::AssignCapture {
var: "v".to_string(),
decl_type: "STRING".to_string(),
cmd: Box::new(StepKind::Echo(crate::ast::Arg::String(
"x".to_string(),
false,
))),
},
StepKind::AwaitCapture {
out_var: "o".to_string(),
out_type: "STRING".to_string(),
task_var: "t".to_string(),
},
StepKind::AsyncBlock { body: Vec::new() },
StepKind::AssignAsync {
var: "t".to_string(),
decl_type: "HANDLE".to_string(),
body: Vec::new(),
},
StepKind::Await {
var: "t".to_string(),
},
StepKind::Cancel {
var: "t".to_string(),
},
StepKind::Timeout {
duration: Arg::String("1s".to_string(), false),
body: Vec::new(),
},
StepKind::FuncDef {
name: "F".to_string(),
params: Vec::new(),
body: Vec::new(),
},
StepKind::Call {
name: "F".to_string(),
args: Vec::new(),
},
StepKind::Return {
expr: Box::new(Expr::Literal(Value::bool(true))),
},
StepKind::While {
cond: Box::new(Expr::Literal(Value::bool(true))),
body: Vec::new(),
},
StepKind::Break,
StepKind::Continue,
];
let registry = all_structural_metadata();
for kind in &dummies {
let Some(name) = metadata_name(kind) else {
continue;
};
assert!(
registry.iter().any(|meta| meta.name == name),
"no structural metadata entry for {}",
name
);
}
}
}