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/*
* Copyright 2019 The Starlark in Rust Authors.
* Copyright (c) Facebook, Inc. and its affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
//! Function parameters.
use std::cell::Cell;
use std::cmp;
use std::collections::HashMap;
use std::iter;
use allocative::Allocative;
use dupe::Dupe;
use starlark_derive::Freeze;
use starlark_derive::Trace;
use starlark_map::small_map::SmallMap;
use starlark_map::Hashed;
use crate as starlark;
use crate::coerce::coerce;
use crate::coerce::Coerce;
use crate::collections::symbol_map::SymbolMap;
use crate::docs::DocParam;
use crate::docs::DocString;
use crate::eval::runtime::arguments::ArgSymbol;
use crate::eval::runtime::arguments::ArgumentsImpl;
use crate::eval::runtime::arguments::FunctionError;
use crate::eval::runtime::arguments::ResolvedArgName;
use crate::eval::Arguments;
use crate::eval::Evaluator;
use crate::hint::unlikely;
use crate::typing::Ty;
use crate::values::dict::Dict;
use crate::values::dict::DictRef;
use crate::values::Heap;
use crate::values::StringValue;
use crate::values::UnpackValue;
use crate::values::Value;
use crate::values::ValueLike;
#[derive(Debug, Copy, Clone, Dupe, Coerce, PartialEq, Trace, Freeze, Allocative)]
#[repr(C)]
pub(crate) enum ParameterKind<V> {
Required,
/// When optional parameter is not supplied, there's no error,
/// but the slot remains `None`.
///
/// This is used only in native code, parameters of type `Option<T>` become `Optional`.
Optional,
Defaulted(V),
Args,
KWargs,
}
#[derive(Debug, Copy, Clone, Dupe, PartialEq, Eq, PartialOrd, Ord)]
enum CurrentParameterStyle {
/// Parameter can be only filled positionally.
PosOnly,
/// Parameter can be filled positionally or by name.
PosOrNamed,
/// Parameter can be filled by name only.
NamedOnly,
/// No more args accepted.
NoMore,
}
/// Builder for [`ParametersSpec`]
pub struct ParametersSpecBuilder<V> {
function_name: String,
params: Vec<(String, ParameterKind<V>)>,
names: SymbolMap<u32>,
/// Number of parameters that can be filled only positionally.
positional_only: usize,
/// Number of parameters that can be filled positionally.
positional: usize,
/// Has the no_args been passed
current_style: CurrentParameterStyle,
args: Option<usize>,
kwargs: Option<usize>,
}
/// Define a list of parameters. This code assumes that all names are distinct and that
/// `*args`/`**kwargs` occur in well-formed locations.
// V = Value, or FrozenValue
#[derive(Debug, Clone, Trace, Freeze, Allocative)]
#[repr(C)]
pub struct ParametersSpec<V> {
/// Only used in error messages
function_name: String,
/// Parameters in the order they occur.
param_kinds: Box<[ParameterKind<V>]>,
/// Parameter names in the order they occur.
param_names: Box<[String]>,
/// Mapping from name to index where the argument lives.
#[freeze(identity)]
pub(crate) names: SymbolMap<u32>,
/// Number of arguments that can be filled only positionally.
positional_only: u32,
/// Number of arguments that can be filled positionally.
/// Excludes *args/**kwargs, keyword arguments after *args
positional: u32,
/// The index at which *args should go
args: Option<u32>,
/// The index at which **kwargs should go
kwargs: Option<u32>,
}
// Can't derive this since we don't want ParameterKind to be public
unsafe impl<From: Coerce<To>, To> Coerce<ParametersSpec<To>> for ParametersSpec<From> {}
impl<V: Copy> ParametersSpecBuilder<V> {
fn add(&mut self, name: &str, val: ParameterKind<V>) {
assert!(!matches!(val, ParameterKind::Args | ParameterKind::KWargs));
// Regular arguments cannot follow `**kwargs`, but can follow `*args`.
assert!(self.current_style < CurrentParameterStyle::NoMore);
assert!(self.kwargs.is_none());
let i = self.params.len();
self.params.push((name.to_owned(), val));
if self.current_style != CurrentParameterStyle::PosOnly {
let old = self.names.insert(name, i.try_into().unwrap());
assert!(old.is_none(), "Repeated parameter `{}`", name);
}
if self.args.is_none() && self.current_style != CurrentParameterStyle::NamedOnly {
// If you've already seen `args` or `no_args`, you can't enter these
// positionally
self.positional = i + 1;
if self.current_style == CurrentParameterStyle::PosOnly {
self.positional_only = i + 1;
}
}
}
/// Add a required parameter. Will be an error if the caller doesn't supply
/// it. If you want to supply a position-only argument, prepend a `$` to
/// the name.
pub fn required(&mut self, name: &str) {
self.add(name, ParameterKind::Required);
}
/// Add an optional parameter. Will be None if the caller doesn't supply it.
/// If you want to supply a position-only argument, prepend a `$` to the
/// name.
pub fn optional(&mut self, name: &str) {
self.add(name, ParameterKind::Optional);
}
/// Add an optional parameter. Will be the default value if the caller
/// doesn't supply it. If you want to supply a position-only argument,
/// prepend a `$` to the name.
pub fn defaulted(&mut self, name: &str, val: V) {
self.add(name, ParameterKind::Defaulted(val));
}
/// Add an `*args` parameter which will be an iterable sequence of parameters,
/// recorded into a [`Vec`]. A function can only have one `args`
/// parameter. After this call, any subsequent
/// [`required`](ParametersSpecBuilder::required),
/// [`optional`](ParametersSpecBuilder::optional) or
/// [`defaulted`](ParametersSpecBuilder::defaulted)
/// parameters can _only_ be supplied by name.
pub fn args(&mut self) {
assert!(self.args.is_none());
assert!(self.current_style < CurrentParameterStyle::NamedOnly);
assert!(self.kwargs.is_none());
self.params.push(("*args".to_owned(), ParameterKind::Args));
self.args = Some(self.params.len() - 1);
self.current_style = CurrentParameterStyle::NamedOnly;
}
/// Following parameters can be filled positionally or by name.
pub fn no_more_positional_only_args(&mut self) {
assert_eq!(self.current_style, CurrentParameterStyle::PosOnly);
self.current_style = CurrentParameterStyle::PosOrNamed;
}
/// This function has no `*args` parameter, corresponds to the Python parameter `*`.
/// After this call, any subsequent
/// [`required`](ParametersSpecBuilder::required),
/// [`optional`](ParametersSpecBuilder::optional) or
/// [`defaulted`](ParametersSpecBuilder::defaulted)
/// parameters can _only_ be supplied by name.
pub fn no_more_positional_args(&mut self) {
assert!(self.args.is_none());
assert!(self.current_style < CurrentParameterStyle::NamedOnly);
assert!(self.kwargs.is_none());
self.current_style = CurrentParameterStyle::NamedOnly;
}
/// Add a `**kwargs` parameter which will be a dictionary, recorded into a [`SmallMap`].
/// A function can only have one `kwargs` parameter.
/// parameter. After this call, any subsequent
/// [`required`](ParametersSpecBuilder::required),
/// [`optional`](ParametersSpecBuilder::optional) or
/// [`defaulted`](ParametersSpecBuilder::defaulted)
/// parameters can _only_ be supplied by position.
pub fn kwargs(&mut self) {
assert!(self.kwargs.is_none());
self.params
.push(("**kwargs".to_owned(), ParameterKind::KWargs));
self.current_style = CurrentParameterStyle::NoMore;
self.kwargs = Some(self.params.len() - 1);
}
/// Construct the parameters specification.
pub fn finish(self) -> ParametersSpec<V> {
let ParametersSpecBuilder {
function_name,
positional_only,
positional,
args,
current_style,
kwargs,
params,
names,
} = self;
let _ = current_style;
let positional_only: u32 = positional_only.try_into().unwrap();
let positional: u32 = positional.try_into().unwrap();
assert!(positional_only <= positional);
ParametersSpec {
function_name,
param_kinds: params.iter().map(|p| p.1).collect(),
param_names: params.into_iter().map(|p| p.0).collect(),
names,
positional_only,
positional,
args: args.map(|args| args.try_into().unwrap()),
kwargs: kwargs.map(|kwargs| kwargs.try_into().unwrap()),
}
}
}
impl<V> ParametersSpec<V> {
/// Create a new [`ParametersSpec`] with the given function name.
pub fn new(function_name: String) -> ParametersSpecBuilder<V> {
Self::with_capacity(function_name, 0)
}
/// Create a new [`ParametersSpec`] with the given function name and an advance capacity hint.
pub fn with_capacity(function_name: String, capacity: usize) -> ParametersSpecBuilder<V> {
ParametersSpecBuilder {
function_name,
params: Vec::with_capacity(capacity),
names: SymbolMap::with_capacity(capacity),
positional_only: 0,
positional: 0,
current_style: CurrentParameterStyle::PosOnly,
args: None,
kwargs: None,
}
}
/// Produce an approximate signature for the function, combining the name and arguments.
pub fn signature(&self) -> String {
let mut collector = String::new();
self.collect_signature(&mut collector);
collector
}
// Generate a good error message for it
pub(crate) fn collect_signature(&self, collector: &mut String) {
collector.push_str(&self.function_name);
// We used to make the "name" of a function include all its parameters, but that is a lot of
// details and visually crowds out everything else. Try disabling, although we might want it
// in some contexts, so don't delete it.
}
/// Function parameter as they would appear in `def`
/// (excluding types, default values and formatting).
pub fn parameters_str(&self) -> String {
let mut emitted_star = false;
let mut collector = String::new();
for (i, typ) in self.iter_params().enumerate() {
if !collector.is_empty() {
collector.push_str(", ");
}
// TODO: also print `/` for positional-only parameters.
if i == (self.positional as usize)
&& !emitted_star
&& !matches!(typ.1, ParameterKind::Args | ParameterKind::KWargs)
{
collector.push_str("*, ");
emitted_star = true;
}
match typ.1 {
ParameterKind::Args | ParameterKind::KWargs => {
// For `*args` or `**kwargs` param name includes the `*` or `**`.
collector.push_str(typ.0);
emitted_star = true;
}
ParameterKind::Required => {
collector.push_str(typ.0);
}
ParameterKind::Optional | ParameterKind::Defaulted(_) => {
collector.push_str(typ.0);
collector.push_str(" = ...");
}
}
}
collector
}
/// Iterate over the parameters
///
/// Returns an iterator over (parameter index, name, kind)
pub(crate) fn iter_params(&self) -> impl Iterator<Item = (&str, &ParameterKind<V>)> {
assert_eq!(self.param_names.len(), self.param_kinds.len());
self.param_names
.iter()
.map(|name| name.as_str())
.zip(&*self.param_kinds)
}
pub(crate) fn resolve_name(&self, name: Hashed<&str>) -> ResolvedArgName {
let hash = name.hash();
let param_index = self.names.get_hashed_str(name).copied();
ResolvedArgName { hash, param_index }
}
pub(crate) fn has_args_or_kwargs(&self) -> bool {
self.args.is_some() || self.kwargs.is_some()
}
}
impl<'v, V: ValueLike<'v>> ParametersSpec<V> {
/// Number of function parameters.
pub fn len(&self) -> usize {
self.param_kinds.len()
}
/// Move parameters from [`Arguments`] to a list of [`Value`],
/// using the supplied [`ParametersSpec`].
pub fn collect(
&self,
args: &Arguments<'v, '_>,
slots: &[Cell<Option<Value<'v>>>],
heap: &'v Heap,
) -> crate::Result<()> {
self.collect_inline(&args.0, slots, heap)
}
/// Collect `N` arguments.
///
/// This function is called by generated code.
pub fn collect_into<const N: usize>(
&self,
args: &Arguments<'v, '_>,
heap: &'v Heap,
) -> crate::Result<[Cell<Option<Value<'v>>>; N]> {
let slots = [(); N].map(|_| Cell::new(None));
self.collect(args, &slots, heap)?;
Ok(slots)
}
/// A variant of collect that is always inlined
/// for Def and NativeFunction that are hot-spots
#[inline(always)]
pub(crate) fn collect_inline<'a, A: ArgumentsImpl<'v, 'a>>(
&self,
args: &A,
slots: &[Cell<Option<Value<'v>>>],
heap: &'v Heap,
) -> crate::Result<()>
where
'v: 'a,
{
// If the arguments equal the length and the kinds, and we don't have any other args,
// then no_args, *args and **kwargs must all be unset,
// and we don't have to crate args/kwargs objects, we can skip everything else
if args.pos().len() == (self.positional as usize)
&& args.pos().len() == self.param_kinds.len()
&& args.named().is_empty()
&& args.args().is_none()
&& args.kwargs().is_none()
{
for (v, s) in args.pos().iter().zip(slots.iter()) {
s.set(Some(*v));
}
return Ok(());
}
self.collect_slow(args, slots, heap)
}
fn collect_slow<'a, A: ArgumentsImpl<'v, 'a>>(
&self,
args: &A,
slots: &[Cell<Option<Value<'v>>>],
heap: &'v Heap,
) -> crate::Result<()>
where
'v: 'a,
{
/// Lazily initialized `kwargs` object.
#[derive(Default)]
struct LazyKwargs<'v> {
kwargs: Option<SmallMap<StringValue<'v>, Value<'v>>>,
}
impl<'v> LazyKwargs<'v> {
// Return true if the value is a duplicate
#[inline(always)]
fn insert(&mut self, key: Hashed<StringValue<'v>>, val: Value<'v>) -> bool {
match &mut self.kwargs {
None => {
let mut mp = SmallMap::with_capacity(12);
mp.insert_hashed_unique_unchecked(key, val);
self.kwargs = Some(mp);
false
}
Some(mp) => mp.insert_hashed(key, val).is_some(),
}
}
fn alloc(self, heap: &'v Heap) -> Value<'v> {
let kwargs = match self.kwargs {
Some(kwargs) => Dict::new(coerce(kwargs)),
None => Dict::default(),
};
heap.alloc(kwargs)
}
}
let len = self.param_kinds.len();
// We might do unchecked stuff later on, so make sure we have as many slots as we expect
assert!(slots.len() >= len);
let mut star_args = Vec::new();
let mut kwargs = LazyKwargs::default();
let mut next_position = 0;
// First deal with positional parameters
if args.pos().len() <= (self.positional as usize) {
// fast path for when we don't need to bounce down to filling in args
for (v, s) in args.pos().iter().zip(slots.iter()) {
s.set(Some(*v));
}
next_position = args.pos().len();
} else {
for v in args.pos() {
if next_position < (self.positional as usize) {
slots[next_position].set(Some(*v));
next_position += 1;
} else {
star_args.push(*v);
}
}
}
// Next deal with named parameters
// The lowest position at which we've written a name.
// If at the end lowest_name is less than next_position, we got the same variable twice.
// So no duplicate checking until after all positional arguments
let mut lowest_name = usize::MAX;
// Avoid a lot of loop setup etc in the common case
if !args.names().is_empty() {
for ((name, name_value), v) in args.names().iter().zip(args.named()) {
// Safe to use new_unchecked because hash for the Value and str are the same
match name.get_index_from_param_spec(self) {
None => {
kwargs.insert(Hashed::new_unchecked(name.small_hash(), *name_value), *v);
}
Some(i) => {
slots[i].set(Some(*v));
lowest_name = cmp::min(lowest_name, i);
}
}
}
}
// Next up are the *args parameters
if let Some(param_args) = args.args() {
for v in param_args
.iterate(heap)
.map_err(|_| FunctionError::ArgsArrayIsNotIterable)?
{
if next_position < (self.positional as usize) {
slots[next_position].set(Some(v));
next_position += 1;
} else {
star_args.push(v);
}
}
}
// Check if the named arguments clashed with the positional arguments
if unlikely(next_position > lowest_name) {
return Err(FunctionError::RepeatedArg {
name: self.param_names[lowest_name].clone(),
}
.into());
}
// Now insert the kwargs, if there are any
if let Some(param_kwargs) = args.kwargs() {
match DictRef::from_value(param_kwargs) {
Some(y) => {
for (k, v) in y.iter_hashed() {
match StringValue::new(*k.key()) {
None => return Err(FunctionError::ArgsValueIsNotString.into()),
Some(s) => {
let repeat = match self
.names
.get_hashed_string_value(Hashed::new_unchecked(k.hash(), s))
{
None => kwargs.insert(Hashed::new_unchecked(k.hash(), s), v),
Some(i) => {
let this_slot = &slots[*i as usize];
let repeat = this_slot.get().is_some();
this_slot.set(Some(v));
repeat
}
};
if unlikely(repeat) {
return Err(FunctionError::RepeatedArg {
name: s.as_str().to_owned(),
}
.into());
}
}
}
}
}
None => return Err(FunctionError::KwArgsIsNotDict.into()),
}
}
// We have moved parameters into all the relevant slots, so need to finalise things.
// We need to set default values and error if any required values are missing
let kinds = &*self.param_kinds;
// This code is very hot, and setting up iterators was a noticeable bottleneck.
for index in next_position..kinds.len() {
// The number of locals must be at least the number of parameters, see `collect`
// which reserves `max(_, kinds.len())`.
let slot = unsafe { slots.get_unchecked(index) };
let def = unsafe { kinds.get_unchecked(index) };
// We know that up to next_position got filled positionally, so we don't need to check those
if slot.get().is_some() {
continue;
}
match def {
ParameterKind::Required => {
return Err(FunctionError::MissingParameter {
name: self.param_names[index].clone(),
function: self.signature(),
}
.into());
}
ParameterKind::Defaulted(x) => {
slot.set(Some(x.to_value()));
}
_ => {}
}
}
// Now set the kwargs/args slots, if they are requested, and fail it they are absent but used
// Note that we deliberately give warnings about missing parameters _before_ giving warnings
// about unexpected extra parameters, so if a user misspells an argument they get a better error.
if let Some(args_pos) = self.args {
slots[args_pos as usize].set(Some(heap.alloc_tuple(&star_args)));
} else if unlikely(!star_args.is_empty()) {
return Err(FunctionError::ExtraPositionalArg {
count: star_args.len(),
function: self.signature(),
}
.into());
}
if let Some(kwargs_pos) = self.kwargs {
slots[kwargs_pos as usize].set(Some(kwargs.alloc(heap)));
} else if let Some(kwargs) = kwargs.kwargs {
return Err(FunctionError::ExtraNamedArg {
names: kwargs.keys().map(|x| x.as_str().to_owned()).collect(),
function: self.signature(),
}
.into());
}
Ok(())
}
/// Check if current parameters can be filled with given arguments signature.
#[allow(clippy::needless_range_loop)]
pub fn can_fill_with_args(&self, pos: usize, names: &[&str]) -> bool {
let mut filled = vec![false; self.param_kinds.len()];
for p in 0..pos {
if p < (self.positional as usize) {
filled[p] = true;
} else if self.args.is_some() {
// Filled into `*args`.
} else {
return false;
}
}
if pos > (self.positional as usize) && self.args.is_none() {
return false;
}
for name in names {
match self.names.get_str(name) {
Some(i) => {
if filled[*i as usize] {
// Duplicate argument.
return false;
}
filled[*i as usize] = true;
}
None => {
if self.kwargs.is_none() {
return false;
}
}
}
}
for (filled, p) in filled.iter().zip(self.param_kinds.iter()) {
if *filled {
continue;
}
match p {
ParameterKind::Args => {}
ParameterKind::KWargs => {}
ParameterKind::Defaulted(_) => {}
ParameterKind::Optional => {}
ParameterKind::Required => return false,
}
}
true
}
/// Generate documentation for each of the parameters.
///
/// # Arguments
/// * `parameter_types` should be a mapping of parameter index to type
/// * `parameter_docs` should be a mapping of parameter name to possible documentation for
/// that parameter
pub fn documentation(
&self,
parameter_types: Vec<Ty>,
mut parameter_docs: HashMap<String, Option<DocString>>,
) -> Vec<DocParam> {
assert_eq!(
self.param_kinds.len(),
parameter_types.len(),
"function: `{}`",
self.function_name,
);
self.iter_params()
.enumerate()
.zip(parameter_types)
.flat_map(|((i, (name, kind)), typ)| {
let docs = parameter_docs.remove(name).flatten();
let name = name.to_owned();
// Add `/` before the first named parameter.
let only_pos_before = if i != 0 && i == self.positional_only as usize {
Some(DocParam::OnlyPosBefore)
} else {
None
};
// Add `*` before first named-only parameter.
let no_args = match kind {
ParameterKind::Args | ParameterKind::KWargs => None,
ParameterKind::Required
| ParameterKind::Optional
| ParameterKind::Defaulted(_) => {
if i == self.positional as usize {
Some(DocParam::NoArgs)
} else {
None
}
}
};
let doc_param = match kind {
ParameterKind::Required => DocParam::Arg {
name,
docs,
typ,
default_value: None,
},
ParameterKind::Optional => DocParam::Arg {
name,
docs,
typ,
default_value: Some("_".to_owned()),
},
ParameterKind::Defaulted(v) => DocParam::Arg {
name,
docs,
typ,
default_value: Some(v.to_value().to_repr()),
},
ParameterKind::Args => DocParam::Args { name, docs, typ },
ParameterKind::KWargs => DocParam::Kwargs { name, docs, typ },
};
only_pos_before
.into_iter()
.chain(no_args)
.chain(iter::once(doc_param))
})
.chain(
// Add last `/`.
if self.positional_only == self.param_kinds.len() as u32
&& self.param_kinds.len() != 0
{
Some(DocParam::OnlyPosBefore)
} else {
None
},
)
.collect()
}
/// Create a [`ParametersParser`] for given arguments.
pub fn parser<R, F>(
&self,
args: &Arguments<'v, '_>,
eval: &mut Evaluator<'v, '_>,
k: F,
) -> crate::Result<R>
where
F: FnOnce(ParametersParser<'v, '_>, &mut Evaluator<'v, '_>) -> crate::Result<R>,
{
eval.alloca_init(
self.len(),
|| Cell::new(None),
|slots, eval| {
self.collect_inline(&args.0, slots, eval.heap())?;
let parser = ParametersParser::new(slots);
k(parser, eval)
},
)
}
}
/// Parse a series of parameters which were specified by [`ParametersSpec`].
///
/// This is usually created with [`ParametersSpec::parser`].
pub struct ParametersParser<'v, 'a>(std::slice::Iter<'a, Cell<Option<Value<'v>>>>);
impl<'v, 'a> ParametersParser<'v, 'a> {
/// Create a parameter parser, which stored parameters into provided slots reference.
pub fn new(slots: &'a [Cell<Option<Value<'v>>>]) -> Self {
Self(slots.iter())
}
fn get_next(&mut self) -> Option<Value<'v>> {
let v = self
.0
.next()
.expect("ParametersParser: wrong number of requested arguments");
v.get()
}
/// Obtain the next parameter, corresponding to [`ParametersSpecBuilder::optional`].
/// It is an error to request more parameters than were specified.
/// The `name` is only used for error messages.
pub fn next_opt<T: UnpackValue<'v>>(&mut self, name: &str) -> anyhow::Result<Option<T>> {
match self.get_next() {
None => Ok(None),
Some(v) => Ok(Some(T::unpack_named_param(v, name)?)),
}
}
/// Obtain the next parameter, which can't be defined by [`ParametersSpecBuilder::optional`].
/// It is an error to request more parameters than were specified.
/// The `name` is only used for error messages.
pub fn next<T: UnpackValue<'v>>(&mut self, name: &str) -> anyhow::Result<T> {
// After ParametersCollect.done() all variables will be Some,
// apart from those where we called ParametersSpec.optional(),
// and for those we should call next_opt()
// This is definitely not unassigned because ParametersCollect.done checked
// that.
let v = self.get_next().unwrap();
T::unpack_named_param(v, name)
}
}
#[cfg(test)]
mod tests {
use std::collections::HashMap;
use crate::assert::Assert;
use crate::docs::DocParam;
use crate::docs::DocString;
use crate::docs::DocStringKind;
use crate::eval::compiler::def::FrozenDef;
use crate::eval::runtime::params::ParameterKind;
use crate::eval::ParametersSpec;
use crate::typing::Ty;
use crate::values::FrozenValue;
#[test]
fn test_parameter_iteration() {
let mut p = ParametersSpec::<FrozenValue>::new("f".to_owned());
p.required("a");
p.optional("b");
p.no_more_positional_args();
p.optional("c");
p.kwargs();
let p = p.finish();
let params: Vec<(&str, &ParameterKind<FrozenValue>)> = p.iter_params().collect();
let expected: Vec<(&str, &ParameterKind<FrozenValue>)> = vec![
("a", &ParameterKind::Required),
("b", &ParameterKind::Optional),
("c", &ParameterKind::Optional),
("**kwargs", &ParameterKind::KWargs),
];
assert_eq!(expected, params);
let mut p = ParametersSpec::<FrozenValue>::new("f".to_owned());
p.required("a");
p.args();
p.kwargs();
let p = p.finish();
let params: Vec<(&str, &ParameterKind<FrozenValue>)> = p.iter_params().collect();
let expected: Vec<(&str, &ParameterKind<FrozenValue>)> = vec![
("a", &ParameterKind::Required),
("*args", &ParameterKind::Args),
("**kwargs", &ParameterKind::KWargs),
];
assert_eq!(expected, params);
let mut p = ParametersSpec::<FrozenValue>::new("f".to_owned());
p.args();
p.optional("a");
p.optional("b");
let p = p.finish();
let params: Vec<(&str, &ParameterKind<FrozenValue>)> = p.iter_params().collect();
let expected: Vec<(&str, &ParameterKind<FrozenValue>)> = vec![
("*args", &ParameterKind::Args),
("a", &ParameterKind::Optional),
("b", &ParameterKind::Optional),
];
assert_eq!(expected, params);
}
#[test]
fn test_documentation() -> anyhow::Result<()> {
// Make sure that documentation for some odder parameter specs works properly.
let mut p = ParametersSpec::<FrozenValue>::new("f".to_owned());
p.args();
p.optional("a");
p.optional("b");
let p = p.finish();
let expected = vec![
DocParam::Args {
name: "*args".to_owned(),
docs: None,
typ: Ty::any(),
},
DocParam::Arg {
name: "a".to_owned(),
docs: None,
typ: Ty::int(),
default_value: Some("_".to_owned()),
},
DocParam::Arg {
name: "b".to_owned(),
docs: DocString::from_docstring(DocStringKind::Rust, "param b docs"),
typ: Ty::any(),
default_value: Some("_".to_owned()),
},
];
let types = vec![Ty::any(), Ty::int(), Ty::any()];
let mut docs = HashMap::new();
docs.insert("a".to_owned(), None);
docs.insert(
"b".to_owned(),
DocString::from_docstring(DocStringKind::Rust, "param b docs"),
);
let params = p.documentation(types, docs);
assert_eq!(expected, params);
Ok(())
}
#[test]
fn test_parameters_str() {
fn test(sig: &str) {
let a = Assert::new();
let f = a
.pass_module(&format!("def f({sig}): pass"))
.get("f")
.unwrap();
assert_eq!(sig, &f.value().parameters_spec().unwrap().parameters_str());
}
test("");
test("a, b, c, d, e, f, g, h, *args, **kwargs");
test("*, a");
test("x, *, a");
test("*args, a");
test("x, *args, a");
test("**kwargs");
test("a, **kwargs");
}
#[test]
fn test_can_fill_with_args() {
fn test(sig: &str, pos: usize, names: &[&str], expected: bool) {
let a = Assert::new();
let module = a.pass_module(&format!("def f({}): pass", sig));
let f = module.get("f").unwrap().downcast::<FrozenDef>().unwrap();
let parameters_spec = &f.parameters;
assert_eq!(expected, parameters_spec.can_fill_with_args(pos, names));
}
test("", 0, &[], true);
test("", 1, &[], false);
test("", 0, &["a"], false);
test("a", 1, &[], true);
test("a", 0, &["a"], true);
test("a", 1, &["a"], false);
test("a", 0, &["x"], false);
test("a, b = 1", 1, &[], true);
test("a, b = 1", 2, &[], true);
test("a, b = 1", 0, &["a"], true);
test("a, b = 1", 0, &["b"], false);
test("a, b = 1", 0, &["a", "b"], true);
test("*, a", 0, &[], false);
test("*, a", 1, &[], false);
test("*, a", 0, &["a"], true);
test("a, *args", 0, &[], false);
test("a, *args", 1, &[], true);
test("a, *args", 10, &[], true);
test("*args, b", 0, &[], false);
test("*args, b", 1, &[], false);
test("*args, b", 0, &["b"], true);
test("**kwargs", 0, &[], true);
test("**kwargs", 0, &["a"], true);
test("**kwargs", 1, &[], false);
// No test for positional-only args because we can't create them in starlark.
}
}