nandi.uk
Fork of daniellemaywood.uk/gleam — Wasm codegen work
Improve error message for missing target name
author
Alec Ghost
committer
Louis Pilfold
date
(Mar 19, 2025, 12:04 PM UTC)
commit
cd8a2445
cd8a2445476400a872b77052ff7795a97361622d
parent
4f8f7a46
4f8f7a4618a4cf414fea7a94d1ce563cf14ba8d8
+69
-11
+12
-11
compiler-core/src/parse.rs
+12
-11
compiler-core/src/parse.rs
···
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3482
}
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}
3484
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3485
-
// Expect a target name. e.g. `javascript` or `erlang`
3486
-
fn expect_target(&mut self) -> Result<Target, ParseError> {
3485
+
// Expect a target name. e.g. `javascript` or `erlang`.
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+
// The location of the preceding left parenthesis is required
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+
// to give the correct error span in case the target name is missing.
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+
fn expect_target(&mut self, paren_location: SrcSpan) -> Result<Target, ParseError> {
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let (start, t, end) = match self.next_tok() {
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Some(t) => t,
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None => {
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return parse_error(ParseErrorType::UnexpectedEof, SrcSpan { start: 0, end: 0 });
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}
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};
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+
let location = SrcSpan::new(start, end);
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match t {
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Token::Name { name } => match name.as_str() {
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"javascript" => Ok(Target::JavaScript),
···
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"js" => {
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self.warnings
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.push(DeprecatedSyntaxWarning::DeprecatedTargetShorthand {
3500
-
location: SrcSpan { start, end },
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+
location,
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target: Target::JavaScript,
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});
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Ok(Target::JavaScript)
···
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"erl" => {
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self.warnings
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.push(DeprecatedSyntaxWarning::DeprecatedTargetShorthand {
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-
location: SrcSpan { start, end },
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+
location,
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target: Target::Erlang,
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});
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Ok(Target::Erlang)
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}
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-
_ => parse_error(ParseErrorType::UnknownTarget, SrcSpan::new(start, end)),
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+
_ => parse_error(ParseErrorType::UnknownTarget, location),
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},
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-
_ => self.next_tok_unexpected(Target::variant_strings()),
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+
_ => parse_error(ParseErrorType::ExpectedTargetName, paren_location),
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}
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}
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···
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let _ = self.expect_one(&Token::LeftParen)?;
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self.parse_external_attribute(start, end, attributes)
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}
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-
"target" => {
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-
let _ = self.expect_one(&Token::LeftParen)?;
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-
self.parse_target_attribute(start, end, attributes)
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-
}
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+
"target" => self.parse_target_attribute(start, end, attributes),
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"deprecated" => {
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let _ = self.expect_one(&Token::LeftParen)?;
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self.parse_deprecated_attribute(start, end, attributes)
···
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end: u32,
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attributes: &mut Attributes,
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) -> Result<u32, ParseError> {
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-
let target = self.expect_target()?;
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+
let (paren_start, paren_end) = self.expect_one(&Token::LeftParen)?;
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+
let target = self.expect_target(SrcSpan::new(paren_start, paren_end))?;
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if attributes.target.is_some() {
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return parse_error(ParseErrorType::DuplicateAttribute, SrcSpan { start, end });
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}
+5
compiler-core/src/parse/error.rs
+5
compiler-core/src/parse/error.rs
···
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ParseErrorType::ExpectedFunctionDefinition => {
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("I was expecting a function definition after this", vec![])
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}
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+
ParseErrorType::ExpectedTargetName => (
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+
"I was expecting a target name after this",
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+
vec!["Try `erlang`, `javascript`.".into()],
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+
),
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ParseErrorType::ExtraSeparator => (
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"This is an extra delimiter",
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vec!["Hint: Try removing it?".into()],
···
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ExpectedDefinition, // after attributes
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ExpectedDeprecationMessage, // after "deprecated"
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ExpectedFunctionDefinition, // after function-only attributes
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+
ExpectedTargetName, // after "@target("
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ExprLparStart, // it seems "(" was used to start an expression
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ExtraSeparator, // #(1,,) <- the 2nd comma is an extra separator
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IncorrectName, // UpName or DiscardName used when Name was expected
+17
compiler-core/src/parse/snapshots/gleam_core__parse__tests__missing_target.snap
+17
compiler-core/src/parse/snapshots/gleam_core__parse__tests__missing_target.snap
···
1
+
---
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+
source: compiler-core/src/parse/tests.rs
3
+
expression: "\n@target()\npub fn one() {}"
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+
---
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+
----- SOURCE CODE
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+
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+
@target()
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+
pub fn one() {}
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+
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+
----- ERROR
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+
error: Syntax error
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┌─ /src/parse/error.gleam:2:8
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+
│
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+
2 │ @target()
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+
│ ^ I was expecting a target name after this
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+
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+
Try `erlang`, `javascript`.
+17
compiler-core/src/parse/snapshots/gleam_core__parse__tests__missing_target_and_bracket.snap
+17
compiler-core/src/parse/snapshots/gleam_core__parse__tests__missing_target_and_bracket.snap
···
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+
---
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+
source: compiler-core/src/parse/tests.rs
3
+
expression: "\n@target(\npub fn one() {}"
4
+
---
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+
----- SOURCE CODE
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+
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+
@target(
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+
pub fn one() {}
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+
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----- ERROR
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+
error: Syntax error
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┌─ /src/parse/error.gleam:2:8
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+
│
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2 │ @target(
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+
│ ^ I was expecting a target name after this
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+
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+
Try `erlang`, `javascript`.
+18
compiler-core/src/parse/tests.rs
+18
compiler-core/src/parse/tests.rs
···
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}
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#[test]
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+
fn missing_target() {
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+
assert_module_error!(
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+
r#"
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+
@target()
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+
pub fn one() {}"#
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+
);
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+
}
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+
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+
#[test]
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+
fn missing_target_and_bracket() {
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+
assert_module_error!(
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+
r#"
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+
@target(
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+
pub fn one() {}"#
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+
);
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+
}
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+
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+
#[test]
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fn unknown_attribute() {
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assert_module_error!(
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r#"@go_faster()