use crate::SharedString;
use anyhow::{Context as _, Result};
use std::fmt;
#[derive(Clone, Default, Eq, PartialEq, Hash)]
pub struct KeyContext(Vec<ContextEntry>);
#[derive(Clone, Debug, Eq, PartialEq, Hash)]
pub struct ContextEntry {
pub key: SharedString,
pub value: Option<SharedString>,
}
impl<'a> TryFrom<&'a str> for KeyContext {
type Error = anyhow::Error;
fn try_from(value: &'a str) -> Result<Self> {
Self::parse(value)
}
}
impl KeyContext {
pub fn new_with_defaults() -> Self {
let mut context = Self::default();
#[cfg(target_os = "macos")]
context.set("os", "macos");
#[cfg(any(target_os = "linux", target_os = "freebsd"))]
context.set("os", "linux");
#[cfg(target_os = "windows")]
context.set("os", "windows");
#[cfg(not(any(
target_os = "macos",
target_os = "linux",
target_os = "freebsd",
target_os = "windows"
)))]
context.set("os", "unknown");
context
}
pub fn primary(&self) -> Option<&ContextEntry> {
self.0.iter().find(|p| p.value.is_none())
}
pub fn secondary(&self) -> impl Iterator<Item = &ContextEntry> {
let primary = self.primary();
self.0.iter().filter(move |&p| Some(p) != primary)
}
pub fn parse(source: &str) -> Result<Self> {
let mut context = Self::default();
let source = skip_whitespace(source);
Self::parse_expr(source, &mut context)?;
Ok(context)
}
fn parse_expr(mut source: &str, context: &mut Self) -> Result<()> {
if source.is_empty() {
return Ok(());
}
let key = source
.chars()
.take_while(|c| is_identifier_char(*c))
.collect::<String>();
source = skip_whitespace(&source[key.len()..]);
if let Some(suffix) = source.strip_prefix('=') {
source = skip_whitespace(suffix);
let value = source
.chars()
.take_while(|c| is_identifier_char(*c))
.collect::<String>();
source = skip_whitespace(&source[value.len()..]);
context.set(key, value);
} else {
context.add(key);
}
Self::parse_expr(source, context)
}
pub fn is_empty(&self) -> bool {
self.0.is_empty()
}
pub fn clear(&mut self) {
self.0.clear();
}
pub fn extend(&mut self, other: &Self) {
for entry in &other.0 {
if !self.contains(&entry.key) {
self.0.push(entry.clone());
}
}
}
pub fn add<I: Into<SharedString>>(&mut self, identifier: I) {
let key = identifier.into();
if !self.contains(&key) {
self.0.push(ContextEntry { key, value: None })
}
}
pub fn set<S1: Into<SharedString>, S2: Into<SharedString>>(&mut self, key: S1, value: S2) {
let key = key.into();
if !self.contains(&key) {
self.0.push(ContextEntry {
key,
value: Some(value.into()),
})
}
}
pub fn contains(&self, key: &str) -> bool {
self.0.iter().any(|entry| entry.key.as_ref() == key)
}
pub fn get(&self, key: &str) -> Option<&SharedString> {
self.0
.iter()
.find(|entry| entry.key.as_ref() == key)?
.value
.as_ref()
}
}
impl fmt::Debug for KeyContext {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
let mut entries = self.0.iter().peekable();
while let Some(entry) = entries.next() {
if let Some(ref value) = entry.value {
write!(f, "{}={}", entry.key, value)?;
} else {
write!(f, "{}", entry.key)?;
}
if entries.peek().is_some() {
write!(f, " ")?;
}
}
Ok(())
}
}
#[derive(Clone, Debug, Eq, PartialEq, Hash)]
pub enum KeyBindingContextPredicate {
Identifier(SharedString),
Equal(SharedString, SharedString),
NotEqual(SharedString, SharedString),
Descendant(
Box<KeyBindingContextPredicate>,
Box<KeyBindingContextPredicate>,
),
Not(Box<KeyBindingContextPredicate>),
And(
Box<KeyBindingContextPredicate>,
Box<KeyBindingContextPredicate>,
),
Or(
Box<KeyBindingContextPredicate>,
Box<KeyBindingContextPredicate>,
),
}
impl fmt::Display for KeyBindingContextPredicate {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Self::Identifier(name) => write!(f, "{}", name),
Self::Equal(left, right) => write!(f, "{} == {}", left, right),
Self::NotEqual(left, right) => write!(f, "{} != {}", left, right),
Self::Not(pred) => write!(f, "!{}", pred),
Self::Descendant(parent, child) => write!(f, "{} > {}", parent, child),
Self::And(left, right) => write!(f, "({} && {})", left, right),
Self::Or(left, right) => write!(f, "({} || {})", left, right),
}
}
}
impl KeyBindingContextPredicate {
pub fn parse(source: &str) -> Result<Self> {
let source = skip_whitespace(source);
let (predicate, rest) = Self::parse_expr(source, 0)?;
if let Some(next) = rest.chars().next() {
anyhow::bail!("unexpected character '{next:?}'");
} else {
Ok(predicate)
}
}
pub fn depth_of(&self, contexts: &[KeyContext]) -> Option<usize> {
for depth in (0..=contexts.len()).rev() {
let context_slice = &contexts[0..depth];
if self.eval_inner(context_slice, contexts) {
return Some(depth);
}
}
None
}
#[allow(unused)]
pub(crate) fn eval(&self, contexts: &[KeyContext]) -> bool {
self.eval_inner(contexts, contexts)
}
pub fn eval_inner(&self, contexts: &[KeyContext], all_contexts: &[KeyContext]) -> bool {
let Some(context) = contexts.last() else {
return false;
};
match self {
Self::Identifier(name) => context.contains(name),
Self::Equal(left, right) => context
.get(left)
.map(|value| value == right)
.unwrap_or(false),
Self::NotEqual(left, right) => context
.get(left)
.map(|value| value != right)
.unwrap_or(true),
Self::Not(pred) => {
for i in 0..all_contexts.len() {
if pred.eval_inner(&all_contexts[..=i], all_contexts) {
return false;
}
}
true
}
Self::Descendant(parent, child) => {
for i in 0..contexts.len() - 1 {
if parent.eval_inner(&contexts[..=i], all_contexts) {
if !child.eval_inner(&contexts[i + 1..], &contexts[i + 1..]) {
return false;
}
return true;
}
}
false
}
Self::And(left, right) => {
left.eval_inner(contexts, all_contexts) && right.eval_inner(contexts, all_contexts)
}
Self::Or(left, right) => {
left.eval_inner(contexts, all_contexts) || right.eval_inner(contexts, all_contexts)
}
}
}
pub fn is_superset(&self, other: &Self) -> bool {
if self == other {
return true;
}
if let KeyBindingContextPredicate::Or(left, right) = self {
return left.is_superset(other) || right.is_superset(other);
}
match other {
KeyBindingContextPredicate::Descendant(_, child) => self.is_superset(child),
KeyBindingContextPredicate::And(left, right) => {
self.is_superset(left) || self.is_superset(right)
}
KeyBindingContextPredicate::Identifier(_) => false,
KeyBindingContextPredicate::Equal(_, _) => false,
KeyBindingContextPredicate::NotEqual(_, _) => false,
KeyBindingContextPredicate::Not(_) => false,
KeyBindingContextPredicate::Or(_, _) => false,
}
}
fn parse_expr(mut source: &str, min_precedence: u32) -> anyhow::Result<(Self, &str)> {
type Op = fn(
KeyBindingContextPredicate,
KeyBindingContextPredicate,
) -> Result<KeyBindingContextPredicate>;
let (mut predicate, rest) = Self::parse_primary(source)?;
source = rest;
'parse: loop {
for (operator, precedence, constructor) in [
(">", PRECEDENCE_CHILD, Self::new_child as Op),
("&&", PRECEDENCE_AND, Self::new_and as Op),
("||", PRECEDENCE_OR, Self::new_or as Op),
("==", PRECEDENCE_EQ, Self::new_eq as Op),
("!=", PRECEDENCE_EQ, Self::new_neq as Op),
] {
if source.starts_with(operator) && precedence >= min_precedence {
source = skip_whitespace(&source[operator.len()..]);
let (right, rest) = Self::parse_expr(source, precedence + 1)?;
predicate = constructor(predicate, right)?;
source = rest;
continue 'parse;
}
}
break;
}
Ok((predicate, source))
}
fn parse_primary(mut source: &str) -> anyhow::Result<(Self, &str)> {
let next = source.chars().next().context("unexpected end")?;
match next {
'(' => {
source = skip_whitespace(&source[1..]);
let (predicate, rest) = Self::parse_expr(source, 0)?;
let stripped = rest.strip_prefix(')').context("expected a ')'")?;
source = skip_whitespace(stripped);
Ok((predicate, source))
}
'!' => {
let source = skip_whitespace(&source[1..]);
let (predicate, source) = Self::parse_expr(source, PRECEDENCE_NOT)?;
Ok((KeyBindingContextPredicate::Not(Box::new(predicate)), source))
}
_ if is_identifier_char(next) => {
let len = source
.find(|c: char| !is_identifier_char(c) && !is_vim_operator_char(c))
.unwrap_or(source.len());
let (identifier, rest) = source.split_at(len);
source = skip_whitespace(rest);
Ok((
KeyBindingContextPredicate::Identifier(identifier.to_string().into()),
source,
))
}
_ if is_vim_operator_char(next) => {
let (operator, rest) = source.split_at(1);
source = skip_whitespace(rest);
Ok((
KeyBindingContextPredicate::Identifier(operator.to_string().into()),
source,
))
}
_ => anyhow::bail!("unexpected character '{next:?}'"),
}
}
fn new_or(self, other: Self) -> Result<Self> {
Ok(Self::Or(Box::new(self), Box::new(other)))
}
fn new_and(self, other: Self) -> Result<Self> {
Ok(Self::And(Box::new(self), Box::new(other)))
}
fn new_child(self, other: Self) -> Result<Self> {
Ok(Self::Descendant(Box::new(self), Box::new(other)))
}
fn new_eq(self, other: Self) -> Result<Self> {
if let (Self::Identifier(left), Self::Identifier(right)) = (self, other) {
Ok(Self::Equal(left, right))
} else {
anyhow::bail!("operands of == must be identifiers");
}
}
fn new_neq(self, other: Self) -> Result<Self> {
if let (Self::Identifier(left), Self::Identifier(right)) = (self, other) {
Ok(Self::NotEqual(left, right))
} else {
anyhow::bail!("operands of != must be identifiers");
}
}
}
const PRECEDENCE_CHILD: u32 = 1;
const PRECEDENCE_OR: u32 = 2;
const PRECEDENCE_AND: u32 = 3;
const PRECEDENCE_EQ: u32 = 4;
const PRECEDENCE_NOT: u32 = 5;
fn is_identifier_char(c: char) -> bool {
c.is_alphanumeric() || c == '_' || c == '-'
}
fn is_vim_operator_char(c: char) -> bool {
c == '>' || c == '<' || c == '~' || c == '"' || c == '?'
}
fn skip_whitespace(source: &str) -> &str {
let len = source
.find(|c: char| !c.is_whitespace())
.unwrap_or(source.len());
&source[len..]
}
#[cfg(test)]
mod tests {
use core::slice;
use super::*;
use crate as gpui;
use KeyBindingContextPredicate::*;
#[test]
fn test_actions_definition() {
{
actions!(test_only, [A, B, C, D, E, F, G]);
}
{
actions!(
test_only,
[
H, I, J, K, L, M, N, ]
);
}
}
#[test]
fn test_parse_context() {
let mut expected = KeyContext::default();
expected.add("baz");
expected.set("foo", "bar");
assert_eq!(KeyContext::parse("baz foo=bar").unwrap(), expected);
assert_eq!(KeyContext::parse("baz foo = bar").unwrap(), expected);
assert_eq!(
KeyContext::parse(" baz foo = bar baz").unwrap(),
expected
);
assert_eq!(KeyContext::parse(" baz foo = bar").unwrap(), expected);
}
#[test]
fn test_parse_identifiers() {
assert_eq!(
KeyBindingContextPredicate::parse("abc12").unwrap(),
Identifier("abc12".into())
);
assert_eq!(
KeyBindingContextPredicate::parse("_1a").unwrap(),
Identifier("_1a".into())
);
}
#[test]
fn test_parse_negations() {
assert_eq!(
KeyBindingContextPredicate::parse("!abc").unwrap(),
Not(Box::new(Identifier("abc".into())))
);
assert_eq!(
KeyBindingContextPredicate::parse(" ! ! abc").unwrap(),
Not(Box::new(Not(Box::new(Identifier("abc".into())))))
);
}
#[test]
fn test_parse_equality_operators() {
assert_eq!(
KeyBindingContextPredicate::parse("a == b").unwrap(),
Equal("a".into(), "b".into())
);
assert_eq!(
KeyBindingContextPredicate::parse("c!=d").unwrap(),
NotEqual("c".into(), "d".into())
);
assert_eq!(
KeyBindingContextPredicate::parse("c == !d")
.unwrap_err()
.to_string(),
"operands of == must be identifiers"
);
}
#[test]
fn test_parse_boolean_operators() {
assert_eq!(
KeyBindingContextPredicate::parse("a || b").unwrap(),
Or(
Box::new(Identifier("a".into())),
Box::new(Identifier("b".into()))
)
);
assert_eq!(
KeyBindingContextPredicate::parse("a || !b && c").unwrap(),
Or(
Box::new(Identifier("a".into())),
Box::new(And(
Box::new(Not(Box::new(Identifier("b".into())))),
Box::new(Identifier("c".into()))
))
)
);
assert_eq!(
KeyBindingContextPredicate::parse("a && b || c&&d").unwrap(),
Or(
Box::new(And(
Box::new(Identifier("a".into())),
Box::new(Identifier("b".into()))
)),
Box::new(And(
Box::new(Identifier("c".into())),
Box::new(Identifier("d".into()))
))
)
);
assert_eq!(
KeyBindingContextPredicate::parse("a == b && c || d == e && f").unwrap(),
Or(
Box::new(And(
Box::new(Equal("a".into(), "b".into())),
Box::new(Identifier("c".into()))
)),
Box::new(And(
Box::new(Equal("d".into(), "e".into())),
Box::new(Identifier("f".into()))
))
)
);
assert_eq!(
KeyBindingContextPredicate::parse("a && b && c && d").unwrap(),
And(
Box::new(And(
Box::new(And(
Box::new(Identifier("a".into())),
Box::new(Identifier("b".into()))
)),
Box::new(Identifier("c".into())),
)),
Box::new(Identifier("d".into()))
),
);
}
#[test]
fn test_parse_parenthesized_expressions() {
assert_eq!(
KeyBindingContextPredicate::parse("a && (b == c || d != e)").unwrap(),
And(
Box::new(Identifier("a".into())),
Box::new(Or(
Box::new(Equal("b".into(), "c".into())),
Box::new(NotEqual("d".into(), "e".into())),
)),
),
);
assert_eq!(
KeyBindingContextPredicate::parse(" ( a || b ) ").unwrap(),
Or(
Box::new(Identifier("a".into())),
Box::new(Identifier("b".into())),
)
);
}
#[test]
fn test_is_superset() {
assert_is_superset("editor", "editor", true);
assert_is_superset("editor", "workspace", false);
assert_is_superset("editor", "editor && vim_mode", true);
assert_is_superset("editor", "mode == full && editor", true);
assert_is_superset("editor && mode == full", "editor", false);
assert_is_superset("editor", "something > editor", true);
assert_is_superset("editor", "editor > menu", false);
assert_is_superset("foo || bar || baz", "bar", true);
assert_is_superset("foo || bar || baz", "quux", false);
#[track_caller]
fn assert_is_superset(a: &str, b: &str, result: bool) {
let a = KeyBindingContextPredicate::parse(a).unwrap();
let b = KeyBindingContextPredicate::parse(b).unwrap();
assert_eq!(a.is_superset(&b), result, "({a:?}).is_superset({b:?})");
}
}
#[test]
fn test_child_operator() {
let predicate = KeyBindingContextPredicate::parse("parent > child").unwrap();
let parent_context = KeyContext::try_from("parent").unwrap();
let child_context = KeyContext::try_from("child").unwrap();
let contexts = vec![parent_context.clone(), child_context.clone()];
assert!(predicate.eval(&contexts));
let grandparent_context = KeyContext::try_from("grandparent").unwrap();
let contexts = vec![
grandparent_context,
parent_context.clone(),
child_context.clone(),
];
assert!(predicate.eval(&contexts));
let other_context = KeyContext::try_from("other").unwrap();
let contexts = vec![other_context.clone(), child_context.clone()];
assert!(!predicate.eval(&contexts));
let contexts = vec![parent_context.clone(), other_context, child_context.clone()];
assert!(predicate.eval(&contexts));
assert!(!predicate.eval(&[]));
assert!(!predicate.eval(slice::from_ref(&child_context)));
assert!(!predicate.eval(&[parent_context]));
let zany_predicate = KeyBindingContextPredicate::parse("child > child").unwrap();
assert!(!zany_predicate.eval(slice::from_ref(&child_context)));
assert!(zany_predicate.eval(&[child_context.clone(), child_context]));
}
#[test]
fn test_not_operator() {
let not_predicate = KeyBindingContextPredicate::parse("!editor").unwrap();
let editor_context = KeyContext::try_from("editor").unwrap();
let workspace_context = KeyContext::try_from("workspace").unwrap();
let parent_context = KeyContext::try_from("parent").unwrap();
let child_context = KeyContext::try_from("child").unwrap();
assert!(not_predicate.eval(slice::from_ref(&workspace_context)));
assert!(!not_predicate.eval(slice::from_ref(&editor_context)));
assert!(!not_predicate.eval(&[editor_context.clone(), workspace_context.clone()]));
assert!(!not_predicate.eval(&[workspace_context.clone(), editor_context.clone()]));
let complex_not = KeyBindingContextPredicate::parse("!editor && workspace").unwrap();
assert!(complex_not.eval(slice::from_ref(&workspace_context)));
assert!(!complex_not.eval(&[editor_context.clone(), workspace_context.clone()]));
let not_mode_predicate = KeyBindingContextPredicate::parse("!(mode == full)").unwrap();
let mut mode_context = KeyContext::default();
mode_context.set("mode", "full");
assert!(!not_mode_predicate.eval(&[mode_context.clone()]));
let mut other_mode_context = KeyContext::default();
other_mode_context.set("mode", "partial");
assert!(not_mode_predicate.eval(&[other_mode_context]));
let not_descendant = KeyBindingContextPredicate::parse("!(parent > child)").unwrap();
assert!(not_descendant.eval(slice::from_ref(&parent_context)));
assert!(not_descendant.eval(slice::from_ref(&child_context)));
assert!(!not_descendant.eval(&[parent_context.clone(), child_context.clone()]));
let not_descendant = KeyBindingContextPredicate::parse("parent > !child").unwrap();
assert!(!not_descendant.eval(slice::from_ref(&parent_context)));
assert!(!not_descendant.eval(slice::from_ref(&child_context)));
assert!(!not_descendant.eval(&[parent_context, child_context]));
let double_not = KeyBindingContextPredicate::parse("!!editor").unwrap();
assert!(double_not.eval(slice::from_ref(&editor_context)));
assert!(!double_not.eval(slice::from_ref(&workspace_context)));
let workspace_context = KeyContext::try_from("Workspace").unwrap();
let pane_context = KeyContext::try_from("Pane").unwrap();
let editor_context = KeyContext::try_from("Editor").unwrap();
let workspace_pane_editor = vec![
workspace_context.clone(),
pane_context.clone(),
editor_context.clone(),
];
let pane_pane_editor = KeyBindingContextPredicate::parse("Pane > (Pane > Editor)").unwrap();
assert!(!pane_pane_editor.eval(&workspace_pane_editor));
let workspace_pane_editor_predicate =
KeyBindingContextPredicate::parse("Workspace > Pane > Editor").unwrap();
assert!(workspace_pane_editor_predicate.eval(&workspace_pane_editor));
let pane_pane_then_editor =
KeyBindingContextPredicate::parse("(Pane > Pane) > Editor").unwrap();
assert!(!pane_pane_then_editor.eval(&workspace_pane_editor));
let pane_not_workspace = KeyBindingContextPredicate::parse("Pane > !Workspace").unwrap();
assert!(pane_not_workspace.eval(&[pane_context.clone(), editor_context.clone()]));
assert!(!pane_not_workspace.eval(&[pane_context.clone(), workspace_context.clone()]));
let not_workspace = KeyBindingContextPredicate::parse("!Workspace").unwrap();
assert!(!not_workspace.eval(slice::from_ref(&workspace_context)));
assert!(not_workspace.eval(slice::from_ref(&pane_context)));
assert!(not_workspace.eval(slice::from_ref(&editor_context)));
assert!(!not_workspace.eval(&workspace_pane_editor));
}
}