Add tests, some comments, to function.rs.

This commit is contained in:
Dimitris Fasarakis Hilliard 2023-02-11 23:03:29 +02:00
parent e7f14ab9b8
commit a0786ea872
16 changed files with 2265 additions and 7 deletions

View file

@ -1,8 +1,10 @@
// Contains functions that perform validation and parsing of arguments and parameters.
// Checks apply both to functions and to lambdas.
use crate::ast;
use crate::error::{LexicalError, LexicalErrorType};
use rustc_hash::FxHashSet;
pub struct ArgumentList {
pub(crate) struct ArgumentList {
pub args: Vec<ast::Expr>,
pub keywords: Vec<ast::Keyword>,
}
@ -10,7 +12,10 @@ pub struct ArgumentList {
type ParameterDefs = (Vec<ast::Arg>, Vec<ast::Arg>, Vec<ast::Expr>);
type ParameterDef = (ast::Arg, Option<ast::Expr>);
pub fn validate_arguments(arguments: ast::Arguments) -> Result<ast::Arguments, LexicalError> {
// Perform validation of function/lambda arguments in a function definition.
pub(crate) fn validate_arguments(
arguments: ast::Arguments,
) -> Result<ast::Arguments, LexicalError> {
let mut all_args: Vec<&ast::Located<ast::ArgData>> = vec![];
all_args.extend(arguments.posonlyargs.iter());
@ -29,6 +34,7 @@ pub fn validate_arguments(arguments: ast::Arguments) -> Result<ast::Arguments, L
let mut all_arg_names = FxHashSet::with_hasher(Default::default());
for arg in all_args {
let arg_name = &arg.node.arg;
// Check for duplicate arguments in the function definition.
if !all_arg_names.insert(arg_name) {
return Err(LexicalError {
error: LexicalErrorType::DuplicateArgumentError(arg_name.to_string()),
@ -40,7 +46,8 @@ pub fn validate_arguments(arguments: ast::Arguments) -> Result<ast::Arguments, L
Ok(arguments)
}
pub fn parse_params(
// Parse parameters as supplied during a function/lambda *definition*.
pub(crate) fn parse_params(
params: (Vec<ParameterDef>, Vec<ParameterDef>),
) -> Result<ParameterDefs, LexicalError> {
let mut pos_only = Vec::with_capacity(params.0.len());
@ -52,7 +59,7 @@ pub fn parse_params(
defaults.push(default);
} else if !defaults.is_empty() {
// Once we have started with defaults, all remaining arguments must
// have defaults
// have defaults.
return Err(LexicalError {
error: LexicalErrorType::DefaultArgumentError,
location: name.location,
@ -79,7 +86,8 @@ type FunctionArgument = (
ast::Expr,
);
pub fn parse_args(func_args: Vec<FunctionArgument>) -> Result<ArgumentList, LexicalError> {
// Parse arguments as supplied during a function/lambda *call*.
pub(crate) fn parse_args(func_args: Vec<FunctionArgument>) -> Result<ArgumentList, LexicalError> {
let mut args = vec![];
let mut keywords = vec![];
@ -89,6 +97,7 @@ pub fn parse_args(func_args: Vec<FunctionArgument>) -> Result<ArgumentList, Lexi
for (name, value) in func_args {
match name {
Some((start, end, name)) => {
// Check for duplicate keyword arguments in the call.
if let Some(keyword_name) = &name {
if keyword_names.contains(keyword_name) {
return Err(LexicalError {
@ -111,13 +120,14 @@ pub fn parse_args(func_args: Vec<FunctionArgument>) -> Result<ArgumentList, Lexi
));
}
None => {
// Allow starred arguments after keyword arguments but
// not after double-starred arguments.
// Positional arguments mustn't follow keyword arguments.
if !keywords.is_empty() && !is_starred(&value) {
return Err(LexicalError {
error: LexicalErrorType::PositionalArgumentError,
location: value.location,
});
// Allow starred arguments after keyword arguments but
// not after double-starred arguments.
} else if double_starred {
return Err(LexicalError {
error: LexicalErrorType::UnpackedArgumentError,
@ -132,6 +142,86 @@ pub fn parse_args(func_args: Vec<FunctionArgument>) -> Result<ArgumentList, Lexi
Ok(ArgumentList { args, keywords })
}
// Check if an expression is a starred expression.
fn is_starred(exp: &ast::Expr) -> bool {
matches!(exp.node, ast::ExprKind::Starred { .. })
}
#[cfg(test)]
mod tests {
use crate::error::{LexicalErrorType, ParseErrorType};
use crate::parser::parse_program;
macro_rules! function_and_lambda {
($($name:ident: $code:expr,)*) => {
$(
#[test]
fn $name() {
let parse_ast = parse_program($code, "<test>");
insta::assert_debug_snapshot!(parse_ast);
}
)*
}
}
function_and_lambda! {
test_function_no_args: "def f(): pass",
test_function_pos_args: "def f(a, b, c): pass",
test_function_pos_args_with_defaults: "def f(a, b=20, c=30): pass",
test_function_kw_only_args: "def f(*, a, b, c): pass",
test_function_kw_only_args_with_defaults: "def f(*, a, b=20, c=30): pass",
test_function_pos_and_kw_only_args: "def f(a, b, c, *, d, e, f): pass",
test_function_pos_and_kw_only_args_with_defaults: "def f(a, b, c, *, d, e=20, f=30): pass",
test_function_pos_and_kw_only_args_with_defaults_and_varargs: "def f(a, b, c, *args, d, e=20, f=30): pass",
test_function_pos_and_kw_only_args_with_defaults_and_varargs_and_kwargs: "def f(a, b, c, *args, d, e=20, f=30, **kwargs): pass",
test_lambda_no_args: "lambda: 1",
test_lambda_pos_args: "lambda a, b, c: 1",
test_lambda_pos_args_with_defaults: "lambda a, b=20, c=30: 1",
test_lambda_kw_only_args: "lambda *, a, b, c: 1",
test_lambda_kw_only_args_with_defaults: "lambda *, a, b=20, c=30: 1",
test_lambda_pos_and_kw_only_args: "lambda a, b, c, *, d, e: 0",
}
fn function_parse_error(src: &str) -> LexicalErrorType {
let parse_ast = parse_program(src, "<test>");
parse_ast
.map_err(|e| match e.error {
ParseErrorType::Lexical(e) => e,
_ => panic!("Expected LexicalError"),
})
.expect_err("Expected error")
}
macro_rules! function_and_lambda_error {
($($name:ident: $code:expr, $error:expr,)*) => {
$(
#[test]
fn $name() {
let error = function_parse_error($code);
assert_eq!(error, $error);
}
)*
}
}
function_and_lambda_error! {
// Check definitions
test_duplicates_f1: "def f(a, a): pass", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_duplicates_f2: "def f(a, *, a): pass", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_duplicates_f3: "def f(a, a=20): pass", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_duplicates_f4: "def f(a, *a): pass", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_duplicates_f5: "def f(a, *, **a): pass", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_duplicates_l1: "lambda a, a: 1", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_duplicates_l2: "lambda a, *, a: 1", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_duplicates_l3: "lambda a, a=20: 1", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_duplicates_l4: "lambda a, *a: 1", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_duplicates_l5: "lambda a, *, **a: 1", LexicalErrorType::DuplicateArgumentError("a".to_string()),
test_default_arg_error_f: "def f(a, b=20, c): pass", LexicalErrorType::DefaultArgumentError,
test_default_arg_error_l: "lambda a, b=20, c: 1", LexicalErrorType::DefaultArgumentError,
// Check some calls.
test_positional_arg_error_f: "f(b=20, c)", LexicalErrorType::PositionalArgumentError,
test_unpacked_arg_error_f: "f(**b, *c)", LexicalErrorType::UnpackedArgumentError,
test_duplicate_kw_f1: "f(a=20, a=30)", LexicalErrorType::DuplicateKeywordArgumentError("a".to_string()),
}
}