naga/front/wgsl/
error.rs

1//! Formatting WGSL front end error messages.
2
3use crate::common::wgsl::TryToWgsl;
4use crate::diagnostic_filter::ConflictingDiagnosticRuleError;
5use crate::error::replace_control_chars;
6use crate::proc::{Alignment, ConstantEvaluatorError, ResolveError};
7use crate::{Scalar, SourceLocation, Span};
8
9use super::parse::directive::enable_extension::{EnableExtension, UnimplementedEnableExtension};
10use super::parse::directive::language_extension::{
11    LanguageExtension, UnimplementedLanguageExtension,
12};
13use super::parse::lexer::Token;
14
15use codespan_reporting::diagnostic::{Diagnostic, Label};
16use codespan_reporting::files::SimpleFile;
17use codespan_reporting::term;
18use thiserror::Error;
19
20use alloc::{
21    borrow::Cow,
22    boxed::Box,
23    format,
24    string::{String, ToString},
25    vec,
26    vec::Vec,
27};
28use core::ops::Range;
29
30#[derive(Clone, Debug)]
31pub struct ParseError {
32    message: String,
33    // The first span should be the primary span, and the other ones should be complementary.
34    labels: Vec<(Span, Cow<'static, str>)>,
35    notes: Vec<String>,
36}
37
38impl ParseError {
39    pub fn labels(&self) -> impl ExactSizeIterator<Item = (Span, &str)> + '_ {
40        self.labels
41            .iter()
42            .map(|&(span, ref msg)| (span, msg.as_ref()))
43    }
44
45    pub fn message(&self) -> &str {
46        &self.message
47    }
48
49    fn diagnostic(&self) -> Diagnostic<()> {
50        let diagnostic = Diagnostic::error()
51            .with_message(self.message.to_string())
52            .with_labels(
53                self.labels
54                    .iter()
55                    .filter_map(|label| label.0.to_range().map(|range| (label, range)))
56                    .map(|(label, range)| {
57                        Label::primary((), range).with_message(label.1.to_string())
58                    })
59                    .collect(),
60            )
61            .with_notes(
62                self.notes
63                    .iter()
64                    .map(|note| format!("note: {note}"))
65                    .collect(),
66            );
67        diagnostic
68    }
69
70    /// Emits a summary of the error to standard error stream.
71    #[cfg(feature = "stderr")]
72    pub fn emit_to_stderr(&self, source: &str) {
73        self.emit_to_stderr_with_path(source, "wgsl")
74    }
75
76    /// Emits a summary of the error to standard error stream.
77    #[cfg(feature = "stderr")]
78    pub fn emit_to_stderr_with_path<P>(&self, source: &str, path: P)
79    where
80        P: AsRef<std::path::Path>,
81    {
82        let path = path.as_ref().display().to_string();
83        let files = SimpleFile::new(path, replace_control_chars(source));
84        let config = term::Config::default();
85
86        cfg_if::cfg_if! {
87            if #[cfg(feature = "termcolor")] {
88                let writer = term::termcolor::StandardStream::stderr(term::termcolor::ColorChoice::Auto);
89                term::emit_to_write_style(&mut writer.lock(), &config, &files, &self.diagnostic())
90                    .expect("cannot write error");
91            } else {
92                let writer = std::io::stderr();
93                term::emit_to_io_write(&mut writer.lock(), &config, &files, &self.diagnostic())
94                    .expect("cannot write error");
95            }
96        }
97    }
98
99    /// Emits a summary of the error to a string.
100    pub fn emit_to_string(&self, source: &str) -> String {
101        self.emit_to_string_with_path(source, "wgsl")
102    }
103
104    /// Emits a summary of the error to a string.
105    pub fn emit_to_string_with_path<P>(&self, source: &str, path: P) -> String
106    where
107        P: AsRef<std::path::Path>,
108    {
109        let path = path.as_ref().display().to_string();
110        let files = SimpleFile::new(path, replace_control_chars(source));
111        let config = term::Config::default();
112
113        let mut writer = crate::error::DiagnosticBuffer::new();
114        writer
115            .emit_to_self(&config, &files, &self.diagnostic())
116            .expect("cannot write error");
117        writer.into_string()
118    }
119
120    /// Returns a [`SourceLocation`] for the first label in the error message.
121    pub fn location(&self, source: &str) -> Option<SourceLocation> {
122        self.labels.first().map(|label| label.0.location(source))
123    }
124}
125
126impl core::fmt::Display for ParseError {
127    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
128        write!(f, "{}", self.message)
129    }
130}
131
132impl core::error::Error for ParseError {}
133
134#[derive(Copy, Clone, Debug, PartialEq)]
135pub enum ExpectedToken<'a> {
136    Token(Token<'a>),
137    Identifier,
138    AfterIdentListComma,
139    AfterIdentListArg,
140    /// LHS expression (identifier component_or_swizzle_specifier?, (`lhs_expression`) component_or_swizzle_specifier?, &`lhs_expression`, *`lhs_expression`)
141    LhsExpression,
142    /// Expected: constant, parenthesized expression, identifier
143    PrimaryExpression,
144    /// Expected: assignment, increment/decrement expression
145    Assignment,
146    /// Expected: 'case', 'default', '}'
147    SwitchItem,
148    /// Expected: ',', ')'
149    WorkgroupSizeSeparator,
150    /// Expected: 'struct', 'let', 'var', 'type', ';', 'fn', eof
151    GlobalItem,
152    /// Access of `var`, `let`, `const`.
153    Variable,
154    /// Access of a function
155    Function,
156    /// The `diagnostic` identifier of the `@diagnostic(…)` attribute.
157    DiagnosticAttribute,
158    /// statement
159    Statement,
160    /// for loop init statement (variable_or_value_statement, variable_updating_statement, func_call_statement)
161    ForInit,
162    /// for loop update statement (variable_updating_statement, func_call_statement)
163    ForUpdate,
164}
165
166#[derive(Clone, Copy, Debug, Error, PartialEq)]
167pub enum NumberError {
168    #[error("invalid numeric literal format")]
169    Invalid,
170    #[error("numeric literal not representable by target type")]
171    NotRepresentable,
172}
173
174#[derive(Copy, Clone, Debug, PartialEq)]
175pub enum InvalidAssignmentType {
176    Other,
177    Swizzle,
178    ImmutableBinding(Span),
179}
180
181#[derive(Clone, Debug)]
182pub(crate) enum Error<'a> {
183    Unexpected(Span, ExpectedToken<'a>),
184    UnexpectedComponents(Span),
185    UnexpectedOperationInConstContext(Span),
186    BadNumber(Span, NumberError),
187    BadMatrixScalarKind(Span, Scalar),
188    BadAccessor(Span),
189    BadTexture(Span),
190    BadTypeCast {
191        span: Span,
192        from_type: String,
193        to_type: String,
194    },
195    NotStorageTexture(Span),
196    BadTextureSampleType {
197        span: Span,
198        scalar: Scalar,
199    },
200    BadIncrDecrReferenceType(Span),
201    InvalidResolve(ResolveError),
202    /// A break if appeared outside of a continuing block
203    InvalidBreakIf(Span),
204    InvalidGatherComponent(Span),
205    InvalidConstructorComponentType(Span, i32),
206    InvalidIdentifierUnderscore(Span),
207    ReservedIdentifierPrefix(Span),
208    UnknownAddressSpace(Span),
209    InvalidLocalVariableAddressSpace(Span),
210    UnknownRayFlag(Span),
211    RepeatedAttribute(Span),
212    UnknownAttribute(Span),
213    UnknownBuiltin(Span),
214    UnknownAccess(Span),
215    UnknownIdent(Span, &'a str),
216    UnknownScalarType(Span),
217    UnknownStorageFormat(Span),
218    UnknownConservativeDepth(Span),
219    UnknownEnableExtension(Span, &'a str),
220    UnknownLanguageExtension(Span, &'a str),
221    UnknownDiagnosticRuleName(Span),
222    SizeAttributeTooLow(Span, u32),
223    AlignAttributeTooLow(Span, Alignment),
224    NonPowerOfTwoAlignAttribute(Span),
225    InconsistentBinding(Span),
226    TypeNotConstructible(Span),
227    TypeNotInferable(Span),
228    InitializationTypeMismatch {
229        name: Span,
230        expected: String,
231        got: String,
232    },
233    DeclMissingTypeAndInit(Span),
234    MissingAttribute(&'static str, Span),
235    InvalidAddrOfOperand(Span),
236    InvalidAtomicPointer(Span),
237    InvalidAtomicOperandType(Span),
238    InvalidRayQueryPointer(Span),
239    NotPointer(Span),
240    NotReference(&'static str, Span),
241    InvalidAssignment {
242        span: Span,
243        ty: InvalidAssignmentType,
244    },
245    ReservedKeyword(Span),
246    /// Redefinition of an identifier (used for both module-scope and local redefinitions).
247    Redefinition {
248        /// Span of the identifier in the previous definition.
249        previous: Span,
250
251        /// Span of the identifier in the new definition.
252        current: Span,
253    },
254    /// A declaration refers to itself directly.
255    RecursiveDeclaration {
256        /// The location of the name of the declaration.
257        ident: Span,
258
259        /// The point at which it is used.
260        usage: Span,
261    },
262    /// A declaration refers to itself indirectly, through one or more other
263    /// definitions.
264    CyclicDeclaration {
265        /// The location of the name of some declaration in the cycle.
266        ident: Span,
267
268        /// The edges of the cycle of references.
269        ///
270        /// Each `(decl, reference)` pair indicates that the declaration whose
271        /// name is `decl` has an identifier at `reference` whose definition is
272        /// the next declaration in the cycle. The last pair's `reference` is
273        /// the same identifier as `ident`, above.
274        path: Box<[(Span, Span)]>,
275    },
276    InvalidSwitchSelector {
277        span: Span,
278    },
279    InvalidSwitchCase {
280        span: Span,
281    },
282    SwitchCaseTypeMismatch {
283        span: Span,
284    },
285    CalledEntryPoint(Span),
286    CalledLocalDecl(Span),
287    WrongArgumentCount {
288        span: Span,
289        expected: Range<u32>,
290        found: u32,
291    },
292    /// No overload of this function accepts this many arguments.
293    TooManyArguments {
294        /// The name of the function being called.
295        function: String,
296
297        /// The function name in the call expression.
298        call_span: Span,
299
300        /// The first argument that is unacceptable.
301        arg_span: Span,
302
303        /// Maximum number of arguments accepted by any overload of
304        /// this function.
305        max_arguments: u32,
306    },
307    /// A value passed to a builtin function has a type that is not
308    /// accepted by any overload of the function.
309    WrongArgumentType {
310        /// The name of the function being called.
311        function: String,
312
313        /// The function name in the call expression.
314        call_span: Span,
315
316        /// The first argument whose type is unacceptable.
317        arg_span: Span,
318
319        /// The index of the first argument whose type is unacceptable.
320        arg_index: u32,
321
322        /// That argument's actual type.
323        arg_ty: String,
324
325        /// The set of argument types that would have been accepted for
326        /// this argument, given the prior arguments.
327        allowed: Vec<String>,
328    },
329    /// A value passed to a builtin function has a type that is not
330    /// accepted, given the earlier arguments' types.
331    InconsistentArgumentType {
332        /// The name of the function being called.
333        function: String,
334
335        /// The function name in the call expression.
336        call_span: Span,
337
338        /// The first unacceptable argument.
339        arg_span: Span,
340
341        /// The index of the first unacceptable argument.
342        arg_index: u32,
343
344        /// The actual type of the first unacceptable argument.
345        arg_ty: String,
346
347        /// The prior argument whose type made the `arg_span` argument
348        /// unacceptable.
349        inconsistent_span: Span,
350
351        /// The index of the `inconsistent_span` argument.
352        inconsistent_index: u32,
353
354        /// The type of the `inconsistent_span` argument.
355        inconsistent_ty: String,
356
357        /// The types that would have been accepted instead of the
358        /// first unacceptable argument.
359        allowed: Vec<String>,
360    },
361    FunctionReturnsVoid(Span),
362    FunctionMustUseUnused(Span),
363    FunctionMustUseReturnsVoid(Span, Span),
364    InvalidWorkGroupUniformLoad(Span),
365    Internal(&'static str),
366    ExpectedConstExprConcreteIntegerScalar(Span),
367    ExpectedNonNegative(Span),
368    ExpectedPositiveArrayLength(Span),
369    MissingWorkgroupSize(Span),
370    ConstantEvaluatorError(Box<ConstantEvaluatorError>, Span),
371    AutoConversion(Box<AutoConversionError>),
372    AutoConversionLeafScalar(Box<AutoConversionLeafScalarError>),
373    ConcretizationFailed(Box<ConcretizationFailedError>),
374    ExceededLimitForNestedBraces {
375        span: Span,
376        limit: u8,
377    },
378    PipelineConstantIDValue(Span),
379    NotBool(Span),
380    ConstAssertFailed(Span),
381    DirectiveAfterFirstGlobalDecl {
382        directive_span: Span,
383    },
384    EnableExtensionNotYetImplemented {
385        kind: UnimplementedEnableExtension,
386        span: Span,
387    },
388    EnableExtensionNotEnabled {
389        kind: EnableExtension,
390        span: Span,
391    },
392    EnableExtensionNotSupported {
393        kind: EnableExtension,
394        span: Span,
395    },
396    LanguageExtensionNotYetImplemented {
397        kind: UnimplementedLanguageExtension,
398        span: Span,
399    },
400    DiagnosticInvalidSeverity {
401        severity_control_name_span: Span,
402    },
403    DiagnosticDuplicateTriggeringRule(ConflictingDiagnosticRuleError),
404    DiagnosticAttributeNotYetImplementedAtParseSite {
405        site_name_plural: &'static str,
406        spans: Vec<Span>,
407    },
408    DiagnosticAttributeNotSupported {
409        on_what: DiagnosticAttributeNotSupportedPosition,
410        spans: Vec<Span>,
411    },
412    SelectUnexpectedArgumentType {
413        arg_span: Span,
414        arg_type: String,
415    },
416    SelectRejectAndAcceptHaveNoCommonType {
417        reject_span: Span,
418        reject_type: String,
419        accept_span: Span,
420        accept_type: String,
421    },
422    ExpectedGlobalVariable {
423        name_span: Span,
424    },
425    StructMemberTooLarge {
426        member_name_span: Span,
427    },
428    TypeTooLarge {
429        span: Span,
430    },
431    UnderspecifiedCooperativeMatrix,
432    InvalidCooperativeLoadType(Span),
433    UnsupportedCooperativeScalar(Span),
434    UnexpectedIdentForEnumerant(Span),
435    UnexpectedExprForEnumerant(Span),
436    UnusedArgsForTemplate(Vec<Span>),
437    UnexpectedTemplate(Span),
438    MissingTemplateArg {
439        span: Span,
440        description: &'static str,
441    },
442    UnexpectedExprForTypeExpression(Span),
443    MissingIncomingPayload(Span),
444}
445
446impl From<ConflictingDiagnosticRuleError> for Error<'_> {
447    fn from(value: ConflictingDiagnosticRuleError) -> Self {
448        Self::DiagnosticDuplicateTriggeringRule(value)
449    }
450}
451
452/// Used for diagnostic refinement in [`Error::DiagnosticAttributeNotSupported`].
453#[derive(Clone, Copy, Debug)]
454pub(crate) enum DiagnosticAttributeNotSupportedPosition {
455    SemicolonInModulePosition,
456    Other { display_plural: &'static str },
457}
458
459impl From<&'static str> for DiagnosticAttributeNotSupportedPosition {
460    fn from(display_plural: &'static str) -> Self {
461        Self::Other { display_plural }
462    }
463}
464
465#[derive(Clone, Debug)]
466pub(crate) struct AutoConversionError {
467    pub dest_span: Span,
468    pub dest_type: String,
469    pub source_span: Span,
470    pub source_type: String,
471}
472
473#[derive(Clone, Debug)]
474pub(crate) struct AutoConversionLeafScalarError {
475    pub dest_span: Span,
476    pub dest_scalar: String,
477    pub source_span: Span,
478    pub source_type: String,
479}
480
481#[derive(Clone, Debug)]
482pub(crate) struct ConcretizationFailedError {
483    pub expr_span: Span,
484    pub expr_type: String,
485    pub concretization_preferences: Vec<(String, ConstantEvaluatorError)>,
486}
487
488impl<'a> Error<'a> {
489    #[cold]
490    #[inline(never)]
491    pub(crate) fn as_parse_error(&self, source: &'a str) -> ParseError {
492        match *self {
493            Error::Unexpected(unexpected_span, expected) => {
494                let expected_str = match expected {
495                    ExpectedToken::Token(token) => match token {
496                        Token::Separator(c) => format!("`{c}`"),
497                        Token::Paren(c) => format!("`{c}`"),
498                        Token::Attribute => "@".to_string(),
499                        Token::Number(_) => "number".to_string(),
500                        Token::Word(s) => s.to_string(),
501                        Token::Operation(c) => format!("operation (`{c}`)"),
502                        Token::LogicalOperation(c) => format!("logical operation (`{c}`)"),
503                        Token::ShiftOperation(c) => format!("bitshift (`{c}{c}`)"),
504                        Token::AssignmentOperation(c) if c == '<' || c == '>' => {
505                            format!("bitshift (`{c}{c}=`)")
506                        }
507                        Token::AssignmentOperation(c) => format!("operation (`{c}=`)"),
508                        Token::IncrementOperation => "increment operation".to_string(),
509                        Token::DecrementOperation => "decrement operation".to_string(),
510                        Token::Arrow => "->".to_string(),
511                        Token::TemplateArgsStart => "template args start".to_string(),
512                        Token::TemplateArgsEnd => "template args end".to_string(),
513                        Token::Unknown(c) => format!("unknown (`{c}`)"),
514                        Token::Trivia => "trivia".to_string(),
515                        Token::DocComment(s) => format!("doc comment ('{s}')"),
516                        Token::ModuleDocComment(s) => format!("module doc comment ('{s}')"),
517                        Token::End => "end".to_string(),
518                    },
519                    ExpectedToken::Identifier => "identifier".to_string(),
520                    ExpectedToken::LhsExpression => "LHS expression (identifier component_or_swizzle_specifier?, (`lhs_expression`) component_or_swizzle_specifier?, &`lhs_expression`, *`lhs_expression`)".to_string(),
521                    ExpectedToken::PrimaryExpression => "expression".to_string(),
522                    ExpectedToken::Assignment => "assignment or increment/decrement".to_string(),
523                    ExpectedToken::SwitchItem => concat!(
524                        "switch item (`case` or `default`) or a closing curly bracket ",
525                        "to signify the end of the switch statement (`}`)"
526                    )
527                    .to_string(),
528                    ExpectedToken::WorkgroupSizeSeparator => {
529                        "workgroup size separator (`,`) or a closing parenthesis".to_string()
530                    }
531                    ExpectedToken::GlobalItem => concat!(
532                        "global item (`struct`, `const`, `var`, `alias`, ",
533                        "`fn`, `diagnostic`, `enable`, `requires`, `;`) ",
534                        "or the end of the file"
535                    )
536                    .to_string(),
537                    ExpectedToken::Variable => "variable access".to_string(),
538                    ExpectedToken::Function => "function name".to_string(),
539                    ExpectedToken::AfterIdentListArg => {
540                        "next argument, trailing comma, or end of list (`,` or `;`)".to_string()
541                    }
542                    ExpectedToken::AfterIdentListComma => {
543                        "next argument or end of list (`;`)".to_string()
544                    }
545                    ExpectedToken::DiagnosticAttribute => {
546                        "the `diagnostic` attribute identifier".to_string()
547                    }
548                    ExpectedToken::Statement => "statement".to_string(),
549                    ExpectedToken::ForInit => "for loop initializer statement (`var`/`let`/`const` declaration, assignment, `i++`/`i--` statement, function call)".to_string(),
550                    ExpectedToken::ForUpdate => "for loop update statement (assignment, `i++`/`i--` statement, function call)".to_string(),
551                };
552                ParseError {
553                    message: format!(
554                        "expected {}, found {:?}",
555                        expected_str, &source[unexpected_span],
556                    ),
557                    labels: vec![(unexpected_span, format!("expected {expected_str}").into())],
558                    notes: vec![],
559                }
560            }
561            Error::UnexpectedComponents(bad_span) => ParseError {
562                message: "unexpected components".to_string(),
563                labels: vec![(bad_span, "unexpected components".into())],
564                notes: vec![],
565            },
566            Error::UnexpectedOperationInConstContext(span) => ParseError {
567                message: "this operation is not supported in a const context".to_string(),
568                labels: vec![(span, "operation not supported here".into())],
569                notes: vec![],
570            },
571            Error::BadNumber(bad_span, ref err) => ParseError {
572                message: format!("{}: `{}`", err, &source[bad_span],),
573                labels: vec![(bad_span, err.to_string().into())],
574                notes: vec![],
575            },
576            Error::BadMatrixScalarKind(span, scalar) => ParseError {
577                message: format!(
578                    "matrix scalar type must be floating-point, but found `{}`",
579                    scalar.to_wgsl_for_diagnostics()
580                ),
581                labels: vec![(span, "must be floating-point (e.g. `f32`)".into())],
582                notes: vec![],
583            },
584            Error::BadAccessor(accessor_span) => ParseError {
585                message: format!("invalid field accessor `{}`", &source[accessor_span],),
586                labels: vec![(accessor_span, "invalid accessor".into())],
587                notes: vec![],
588            },
589            Error::UnknownIdent(ident_span, ident) => ParseError {
590                message: format!("no definition in scope for identifier: `{ident}`"),
591                labels: vec![(ident_span, "unknown identifier".into())],
592                notes: vec![],
593            },
594            Error::UnknownScalarType(bad_span) => ParseError {
595                message: format!("unknown scalar type: `{}`", &source[bad_span]),
596                labels: vec![(bad_span, "unknown scalar type".into())],
597                notes: vec!["Valid scalar types are f32, f64, i32, u32, bool".into()],
598            },
599            Error::NotStorageTexture(bad_span) => ParseError {
600                message: "textureStore can only be applied to storage textures".to_string(),
601                labels: vec![(bad_span, "not a storage texture".into())],
602                notes: vec![],
603            },
604            Error::BadTextureSampleType { span, scalar } => ParseError {
605                message: format!(
606                    "texture sample type must be one of f32, i32 or u32, but found {}",
607                    scalar.to_wgsl_for_diagnostics()
608                ),
609                labels: vec![(span, "must be one of f32, i32 or u32".into())],
610                notes: vec![],
611            },
612            Error::BadIncrDecrReferenceType(span) => ParseError {
613                message: concat!(
614                    "increment/decrement operation requires ",
615                    "reference type to be one of i32 or u32"
616                )
617                .to_string(),
618                labels: vec![(span, "must be a reference type of i32 or u32".into())],
619                notes: vec![],
620            },
621            Error::BadTexture(bad_span) => ParseError {
622                message: format!(
623                    "expected an image, but found `{}` which is not an image",
624                    &source[bad_span]
625                ),
626                labels: vec![(bad_span, "not an image".into())],
627                notes: vec![],
628            },
629            Error::BadTypeCast {
630                span,
631                ref from_type,
632                ref to_type,
633            } => {
634                let msg = format!("cannot cast a {from_type} to a {to_type}");
635                ParseError {
636                    message: msg.clone(),
637                    labels: vec![(span, msg.into())],
638                    notes: vec![],
639                }
640            }
641            Error::InvalidResolve(ref resolve_error) => ParseError {
642                message: resolve_error.to_string(),
643                labels: vec![],
644                notes: vec![],
645            },
646            Error::InvalidBreakIf(bad_span) => ParseError {
647                message: "A break if is only allowed in a continuing block".to_string(),
648                labels: vec![(bad_span, "not in a continuing block".into())],
649                notes: vec![],
650            },
651            Error::InvalidGatherComponent(bad_span) => ParseError {
652                message: format!(
653                    "textureGather component `{}` doesn't exist, must be 0, 1, 2, or 3",
654                    &source[bad_span]
655                ),
656                labels: vec![(bad_span, "invalid component".into())],
657                notes: vec![],
658            },
659            Error::InvalidConstructorComponentType(bad_span, component) => ParseError {
660                message: format!("invalid type for constructor component at index [{component}]"),
661                labels: vec![(bad_span, "invalid component type".into())],
662                notes: vec![],
663            },
664            Error::InvalidIdentifierUnderscore(bad_span) => ParseError {
665                message: "Identifier can't be `_`".to_string(),
666                labels: vec![(bad_span, "invalid identifier".into())],
667                notes: vec![
668                    "Use phony assignment instead (`_ =` notice the absence of `let` or `var`)"
669                        .to_string(),
670                ],
671            },
672            Error::ReservedIdentifierPrefix(bad_span) => ParseError {
673                message: format!(
674                    "Identifier starts with a reserved prefix: `{}`",
675                    &source[bad_span]
676                ),
677                labels: vec![(bad_span, "invalid identifier".into())],
678                notes: vec![],
679            },
680            Error::UnknownAddressSpace(bad_span) => ParseError {
681                message: format!("unknown address space: `{}`", &source[bad_span]),
682                labels: vec![(bad_span, "unknown address space".into())],
683                notes: vec![],
684            },
685            Error::InvalidLocalVariableAddressSpace(bad_span) => ParseError {
686                message: format!("invalid address space for local variable: `{}`", &source[bad_span]),
687                labels: vec![(bad_span, "local variables can only use 'function' address space".into())],
688                notes: vec![],
689            },
690            Error::UnknownRayFlag(bad_span) => ParseError {
691                message: format!("unknown ray flag: `{}`", &source[bad_span]),
692                labels: vec![(bad_span, "unknown ray flag".into())],
693                notes: vec![],
694            },
695            Error::RepeatedAttribute(bad_span) => ParseError {
696                message: format!("repeated attribute: `{}`", &source[bad_span]),
697                labels: vec![(bad_span, "repeated attribute".into())],
698                notes: vec![],
699            },
700            Error::UnknownAttribute(bad_span) => ParseError {
701                message: format!("unknown attribute: `{}`", &source[bad_span]),
702                labels: vec![(bad_span, "unknown attribute".into())],
703                notes: vec![],
704            },
705            Error::UnknownBuiltin(bad_span) => ParseError {
706                message: format!("unknown builtin: `{}`", &source[bad_span]),
707                labels: vec![(bad_span, "unknown builtin".into())],
708                notes: vec![],
709            },
710            Error::UnknownAccess(bad_span) => ParseError {
711                message: format!("unknown access: `{}`", &source[bad_span]),
712                labels: vec![(bad_span, "unknown access".into())],
713                notes: vec![],
714            },
715            Error::UnknownStorageFormat(bad_span) => ParseError {
716                message: format!("unknown storage format: `{}`", &source[bad_span]),
717                labels: vec![(bad_span, "unknown storage format".into())],
718                notes: vec![],
719            },
720            Error::UnknownConservativeDepth(bad_span) => ParseError {
721                message: format!("unknown conservative depth: `{}`", &source[bad_span]),
722                labels: vec![(bad_span, "unknown conservative depth".into())],
723                notes: vec![],
724            },
725            Error::UnknownEnableExtension(span, word) => ParseError {
726                message: format!("unknown enable-extension `{word}`"),
727                labels: vec![(span, "".into())],
728                notes: vec![
729                    "See available extensions at <https://www.w3.org/TR/WGSL/#enable-extension>."
730                        .into(),
731                ],
732            },
733            Error::UnknownLanguageExtension(span, name) => ParseError {
734                message: format!("unknown language extension `{name}`"),
735                labels: vec![(span, "".into())],
736                notes: vec![concat!(
737                    "See available extensions at ",
738                    "<https://www.w3.org/TR/WGSL/#language-extensions-sec>."
739                )
740                .into()],
741            },
742            Error::UnknownDiagnosticRuleName(span) => ParseError {
743                message: format!("unknown `diagnostic(…)` rule name `{}`", &source[span]),
744                labels: vec![(span, "not a valid diagnostic rule name".into())],
745                notes: vec![concat!(
746                    "See available trigger rules at ",
747                    "<https://www.w3.org/TR/WGSL/#filterable-triggering-rules>."
748                )
749                .into()],
750            },
751            Error::SizeAttributeTooLow(bad_span, min_size) => ParseError {
752                message: format!("struct member size must be at least {min_size}"),
753                labels: vec![(bad_span, format!("must be at least {min_size}").into())],
754                notes: vec![],
755            },
756            Error::AlignAttributeTooLow(bad_span, min_align) => ParseError {
757                message: format!("struct member alignment must be at least {min_align}"),
758                labels: vec![(bad_span, format!("must be at least {min_align}").into())],
759                notes: vec![],
760            },
761            Error::NonPowerOfTwoAlignAttribute(bad_span) => ParseError {
762                message: "struct member alignment must be a power of 2".to_string(),
763                labels: vec![(bad_span, "must be a power of 2".into())],
764                notes: vec![],
765            },
766            Error::InconsistentBinding(span) => ParseError {
767                message: "input/output binding is not consistent".to_string(),
768                labels: vec![(span, "input/output binding is not consistent".into())],
769                notes: vec![],
770            },
771            Error::TypeNotConstructible(span) => ParseError {
772                message: format!("type `{}` is not constructible", &source[span]),
773                labels: vec![(span, "type is not constructible".into())],
774                notes: vec![],
775            },
776            Error::TypeNotInferable(span) => ParseError {
777                message: "type can't be inferred".to_string(),
778                labels: vec![(span, "type can't be inferred".into())],
779                notes: vec![],
780            },
781            Error::InitializationTypeMismatch {
782                name,
783                ref expected,
784                ref got,
785            } => ParseError {
786                message: format!(
787                    "the type of `{}` is expected to be `{}`, but got `{}`",
788                    &source[name], expected, got,
789                ),
790                labels: vec![(name, format!("definition of `{}`", &source[name]).into())],
791                notes: vec![],
792            },
793            Error::DeclMissingTypeAndInit(name_span) => ParseError {
794                message: format!(
795                    "declaration of `{}` needs a type specifier or initializer",
796                    &source[name_span]
797                ),
798                labels: vec![(name_span, "needs a type specifier or initializer".into())],
799                notes: vec![],
800            },
801            Error::MissingAttribute(name, name_span) => ParseError {
802                message: format!(
803                    "variable `{}` needs a '{}' attribute",
804                    &source[name_span], name
805                ),
806                labels: vec![(
807                    name_span,
808                    format!("definition of `{}`", &source[name_span]).into(),
809                )],
810                notes: vec![],
811            },
812            Error::InvalidAddrOfOperand(span) => ParseError {
813                message: "cannot take the address of a vector component".to_string(),
814                labels: vec![(span, "invalid operand for address-of".into())],
815                notes: vec![],
816            },
817            Error::InvalidAtomicPointer(span) => ParseError {
818                message: "atomic operation is done on a pointer to a non-atomic".to_string(),
819                labels: vec![(span, "atomic pointer is invalid".into())],
820                notes: vec![],
821            },
822            Error::InvalidAtomicOperandType(span) => ParseError {
823                message: "atomic operand type is inconsistent with the operation".to_string(),
824                labels: vec![(span, "atomic operand type is invalid".into())],
825                notes: vec![],
826            },
827            Error::InvalidRayQueryPointer(span) => ParseError {
828                message: "ray query operation is done on a pointer to a non-ray-query".to_string(),
829                labels: vec![(span, "ray query pointer is invalid".into())],
830                notes: vec![],
831            },
832            Error::NotPointer(span) => ParseError {
833                message: "the operand of the `*` operator must be a pointer".to_string(),
834                labels: vec![(span, "expression is not a pointer".into())],
835                notes: vec![],
836            },
837            Error::NotReference(what, span) => ParseError {
838                message: format!("{what} must be a reference"),
839                labels: vec![(span, "expression is not a reference".into())],
840                notes: vec![],
841            },
842            Error::InvalidAssignment { span, ty } => {
843                let (extra_label, notes) = match ty {
844                    InvalidAssignmentType::Swizzle => (
845                        None,
846                        vec![
847                            "WGSL does not support assignments to swizzles".into(),
848                            "consider assigning each component individually".into(),
849                        ],
850                    ),
851                    InvalidAssignmentType::ImmutableBinding(binding_span) => (
852                        Some((binding_span, "this is an immutable binding".into())),
853                        vec![format!(
854                            "consider declaring `{}` with `var` instead of `let`",
855                            &source[binding_span]
856                        )],
857                    ),
858                    InvalidAssignmentType::Other => (None, vec![]),
859                };
860
861                ParseError {
862                    message: "invalid left-hand side of assignment".into(),
863                    labels: core::iter::once((span, "cannot assign to this expression".into()))
864                        .chain(extra_label)
865                        .collect(),
866                    notes,
867                }
868            }
869            Error::ReservedKeyword(name_span) => ParseError {
870                message: format!("name `{}` is a reserved keyword", &source[name_span]),
871                labels: vec![(
872                    name_span,
873                    format!("definition of `{}`", &source[name_span]).into(),
874                )],
875                notes: vec![],
876            },
877            Error::Redefinition { previous, current } => ParseError {
878                message: format!("redefinition of `{}`", &source[current]),
879                labels: vec![
880                    (
881                        current,
882                        format!("redefinition of `{}`", &source[current]).into(),
883                    ),
884                    (
885                        previous,
886                        format!("previous definition of `{}`", &source[previous]).into(),
887                    ),
888                ],
889                notes: vec![],
890            },
891            Error::RecursiveDeclaration { ident, usage } => ParseError {
892                message: format!("declaration of `{}` is recursive", &source[ident]),
893                labels: vec![(ident, "".into()), (usage, "uses itself here".into())],
894                notes: vec![],
895            },
896            Error::CyclicDeclaration { ident, ref path } => ParseError {
897                message: format!("declaration of `{}` is cyclic", &source[ident]),
898                labels: path
899                    .iter()
900                    .enumerate()
901                    .flat_map(|(i, &(ident, usage))| {
902                        [
903                            (ident, "".into()),
904                            (
905                                usage,
906                                if i == path.len() - 1 {
907                                    "ending the cycle".into()
908                                } else {
909                                    format!("uses `{}`", &source[ident]).into()
910                                },
911                            ),
912                        ]
913                    })
914                    .collect(),
915                notes: vec![],
916            },
917            Error::InvalidSwitchSelector { span } => ParseError {
918                message: "invalid `switch` selector".to_string(),
919                labels: vec![(
920                    span,
921                    "`switch` selector must be a scalar integer"
922                    .into(),
923                )],
924                notes: vec![],
925            },
926            Error::InvalidSwitchCase { span } => ParseError {
927                message: "invalid `switch` case selector value".to_string(),
928                labels: vec![(
929                    span,
930                    "`switch` case selector must be a scalar integer const expression"
931                    .into(),
932                )],
933                notes: vec![],
934            },
935            Error::SwitchCaseTypeMismatch { span } => ParseError {
936                message: "invalid `switch` case selector value".to_string(),
937                labels: vec![(
938                    span,
939                    "`switch` case selector must have the same type as the `switch` selector expression"
940                    .into(),
941                )],
942                notes: vec![],
943            },
944            Error::CalledEntryPoint(span) => ParseError {
945                message: "entry point cannot be called".to_string(),
946                labels: vec![(span, "entry point cannot be called".into())],
947                notes: vec![],
948            },
949            Error::CalledLocalDecl(span) => ParseError {
950                message: "local declaration cannot be called".to_string(),
951                labels: vec![(span, "local declaration cannot be called".into())],
952                notes: vec![],
953            },
954            Error::WrongArgumentCount {
955                span,
956                ref expected,
957                found,
958            } => ParseError {
959                message: format!(
960                    "wrong number of arguments: expected {}, found {}",
961                    if expected.len() < 2 {
962                        format!("{}", expected.start)
963                    } else {
964                        format!("{}..{}", expected.start, expected.end)
965                    },
966                    found
967                ),
968                labels: vec![(span, "wrong number of arguments".into())],
969                notes: vec![],
970            },
971            Error::TooManyArguments {
972                ref function,
973                call_span,
974                arg_span,
975                max_arguments,
976            } => ParseError {
977                message: format!("too many arguments passed to `{function}`"),
978                labels: vec![
979                    (call_span, "".into()),
980                    (arg_span, format!("unexpected argument #{}", max_arguments + 1).into())
981                ],
982                notes: vec![
983                    format!("The `{function}` function accepts at most {max_arguments} argument(s)")
984                ],
985            },
986            Error::WrongArgumentType {
987                ref function,
988                call_span,
989                arg_span,
990                arg_index,
991                ref arg_ty,
992                ref allowed,
993            } => {
994                let message = format!(
995                    "wrong type passed as argument #{} to `{function}`",
996                    arg_index + 1,
997                );
998                let labels = vec![
999                    (call_span, "".into()),
1000                    (arg_span, format!("argument #{} has type `{arg_ty}`", arg_index + 1).into())
1001                ];
1002
1003                let mut notes = vec![];
1004                notes.push(format!("`{function}` accepts the following types for argument #{}:", arg_index + 1));
1005                notes.extend(allowed.iter().map(|ty| format!("allowed type: {ty}")));
1006
1007                ParseError { message, labels, notes }
1008            },
1009            Error::InconsistentArgumentType {
1010                ref function,
1011                call_span,
1012                arg_span,
1013                arg_index,
1014                ref arg_ty,
1015                inconsistent_span,
1016                inconsistent_index,
1017                ref inconsistent_ty,
1018                ref allowed
1019            } => {
1020                let message = format!(
1021                    "inconsistent type passed as argument #{} to `{function}`",
1022                    arg_index + 1,
1023                );
1024                let labels = vec![
1025                    (call_span, "".into()),
1026                    (arg_span, format!("argument #{} has type {arg_ty}", arg_index + 1).into()),
1027                    (inconsistent_span, format!(
1028                        "this argument has type {inconsistent_ty}, which constrains subsequent arguments"
1029                    ).into()),
1030                ];
1031                let mut notes = vec![
1032                    format!("Because argument #{} has type {inconsistent_ty}, only the following types", inconsistent_index + 1),
1033                    format!("(or types that automatically convert to them) are accepted for argument #{}:", arg_index + 1),
1034                ];
1035                notes.extend(allowed.iter().map(|ty| format!("allowed type: {ty}")));
1036
1037                ParseError { message, labels, notes }
1038            }
1039            Error::FunctionReturnsVoid(span) => ParseError {
1040                message: "function does not return any value".to_string(),
1041                labels: vec![(span, "".into())],
1042                notes: vec![
1043                    "perhaps you meant to call the function in a separate statement?".into(),
1044                ],
1045            },
1046            Error::FunctionMustUseUnused(call) => ParseError {
1047                message: "unused return value from function annotated with @must_use".into(),
1048                labels: vec![(call, "".into())],
1049                notes: vec![
1050                    format!(
1051                        "function '{}' is declared with `@must_use` attribute",
1052                        &source[call],
1053                    ),
1054                    "use a phony assignment or declare a value using the function call as the initializer".into(),
1055                ],
1056            },
1057            Error::FunctionMustUseReturnsVoid(attr, signature) => ParseError {
1058                message: "function annotated with @must_use but does not return any value".into(),
1059                labels: vec![
1060                    (attr, "".into()),
1061                    (signature, "".into()),
1062                ],
1063                notes: vec![
1064                    "declare a return type or remove the attribute".into(),
1065                ],
1066            },
1067            Error::InvalidWorkGroupUniformLoad(span) => ParseError {
1068                message: "incorrect type passed to workgroupUniformLoad".into(),
1069                labels: vec![(span, "".into())],
1070                notes: vec!["passed type must be a workgroup pointer".into()],
1071            },
1072            Error::Internal(message) => ParseError {
1073                message: "internal WGSL front end error".to_string(),
1074                labels: vec![],
1075                notes: vec![message.into()],
1076            },
1077            Error::ExpectedConstExprConcreteIntegerScalar(span) => ParseError {
1078                message: concat!(
1079                    "must be a const-expression that ",
1080                    "resolves to a concrete integer scalar (`u32` or `i32`)"
1081                )
1082                .to_string(),
1083                labels: vec![(span, "must resolve to `u32` or `i32`".into())],
1084                notes: vec![],
1085            },
1086            Error::ExpectedNonNegative(span) => ParseError {
1087                message: "must be non-negative (>= 0)".to_string(),
1088                labels: vec![(span, "must be non-negative".into())],
1089                notes: vec![],
1090            },
1091            Error::ExpectedPositiveArrayLength(span) => ParseError {
1092                message: "array element count must be positive (> 0)".to_string(),
1093                labels: vec![(span, "must be positive".into())],
1094                notes: vec![],
1095            },
1096            Error::ConstantEvaluatorError(ref e, span) => ParseError {
1097                message: e.to_string(),
1098                labels: vec![(span, "see msg".into())],
1099                notes: vec![],
1100            },
1101            Error::MissingWorkgroupSize(span) => ParseError {
1102                message: "workgroup size is missing on compute shader entry point".to_string(),
1103                labels: vec![(
1104                    span,
1105                    "must be paired with a `@workgroup_size` attribute".into(),
1106                )],
1107                notes: vec![],
1108            },
1109            Error::AutoConversion(ref error) => {
1110                // destructuring ensures all fields are handled
1111                let AutoConversionError {
1112                    dest_span,
1113                    ref dest_type,
1114                    source_span,
1115                    ref source_type,
1116                } = **error;
1117                ParseError {
1118                    message: format!(
1119                        "automatic conversions cannot convert `{source_type}` to `{dest_type}`"
1120                    ),
1121                    labels: vec![
1122                        (
1123                            dest_span,
1124                            format!("a value of type {dest_type} is required here").into(),
1125                        ),
1126                        (
1127                            source_span,
1128                            format!("this expression has type {source_type}").into(),
1129                        ),
1130                    ],
1131                    notes: vec![],
1132                }
1133            }
1134            Error::AutoConversionLeafScalar(ref error) => {
1135                let AutoConversionLeafScalarError {
1136                    dest_span,
1137                    ref dest_scalar,
1138                    source_span,
1139                    ref source_type,
1140                } = **error;
1141                ParseError {
1142                    message: format!(
1143                        "automatic conversions cannot convert elements of `{source_type}` to `{dest_scalar}`"
1144                    ),
1145                    labels: vec![
1146                        (
1147                            dest_span,
1148                            format!(
1149                                "a value with elements of type {dest_scalar} is required here"
1150                            )
1151                            .into(),
1152                        ),
1153                        (
1154                            source_span,
1155                            format!("this expression has type {source_type}").into(),
1156                        ),
1157                    ],
1158                    notes: vec![],
1159                }
1160            }
1161            Error::ConcretizationFailed(ref error) => {
1162                let ConcretizationFailedError {
1163                    expr_span,
1164                    ref expr_type,
1165                    ref concretization_preferences,
1166                } = **error;
1167                ParseError {
1168                    message: "failed to convert expression to a concrete type".to_string(),
1169                    labels: vec![(
1170                        expr_span,
1171                        format!("this expression has type {expr_type}").into(),
1172                    )],
1173                    notes: concretization_preferences
1174                        .iter()
1175                        .map(|&(ref scalar, ref err)|
1176                            format!("the expression couldn't be converted to have {scalar} scalar type: {err}")
1177                        )
1178                        .collect(),
1179                }
1180            }
1181            Error::ExceededLimitForNestedBraces { span, limit } => ParseError {
1182                message: "brace nesting limit reached".into(),
1183                labels: vec![(span, "limit reached at this brace".into())],
1184                notes: vec![format!("nesting limit is currently set to {limit}")],
1185            },
1186            Error::PipelineConstantIDValue(span) => ParseError {
1187                message: "pipeline constant ID must be between 0 and 65535 inclusive".to_string(),
1188                labels: vec![(span, "must be between 0 and 65535 inclusive".into())],
1189                notes: vec![],
1190            },
1191            Error::NotBool(span) => ParseError {
1192                message: "must be a const-expression that resolves to a `bool`".to_string(),
1193                labels: vec![(span, "must resolve to `bool`".into())],
1194                notes: vec![],
1195            },
1196            Error::ConstAssertFailed(span) => ParseError {
1197                message: "`const_assert` failure".to_string(),
1198                labels: vec![(span, "evaluates to `false`".into())],
1199                notes: vec![],
1200            },
1201            Error::DirectiveAfterFirstGlobalDecl { directive_span } => ParseError {
1202                message: "expected global declaration, but found a global directive".into(),
1203                labels: vec![(
1204                    directive_span,
1205                    "written after first global declaration".into(),
1206                )],
1207                notes: vec![concat!(
1208                    "global directives are only allowed before global declarations; ",
1209                    "maybe hoist this closer to the top of the shader module?"
1210                )
1211                .into()],
1212            },
1213            Error::EnableExtensionNotYetImplemented { kind, span } => ParseError {
1214                message: format!(
1215                    "the `{}` enable-extension is not yet supported",
1216                    EnableExtension::Unimplemented(kind).to_ident()
1217                ),
1218                labels: vec![(
1219                    span,
1220                    concat!(
1221                        "this enable-extension specifies standard functionality ",
1222                        "which is not yet implemented in Naga"
1223                    )
1224                    .into(),
1225                )],
1226                notes: vec![format!(
1227                    concat!(
1228                        "Let Naga maintainers know that you ran into this at ",
1229                        "<https://github.com/gfx-rs/wgpu/issues/{}>, ",
1230                        "so they can prioritize it!"
1231                    ),
1232                    kind.tracking_issue_num()
1233                )],
1234            },
1235            Error::EnableExtensionNotEnabled { kind, span } => ParseError {
1236                message: format!("the `{}` enable extension is not enabled", kind.to_ident()),
1237                labels: vec![(
1238                    span,
1239                    format!(
1240                        concat!(
1241                            "the `{}` \"Enable Extension\" is needed for this functionality, ",
1242                            "but it is not currently enabled."
1243                        ),
1244                        kind.to_ident()
1245                    )
1246                    .into(),
1247                )],
1248                notes: if let EnableExtension::Unimplemented(kind) = kind {
1249                    vec![format!(
1250                        concat!(
1251                            "This \"Enable Extension\" is not yet implemented. ",
1252                            "Let Naga maintainers know that you ran into this at ",
1253                            "<https://github.com/gfx-rs/wgpu/issues/{}>, ",
1254                            "so they can prioritize it!"
1255                        ),
1256                        kind.tracking_issue_num()
1257                    )]
1258                } else {
1259                    vec![
1260                        format!(
1261                            "You can enable this extension by adding `enable {};` at the top of the shader, before any other items.",
1262                            kind.to_ident()
1263                        ),
1264                    ]
1265                },
1266            },
1267            Error::EnableExtensionNotSupported { kind, span } => ParseError {
1268                message: format!(
1269                    "the `{}` extension is not supported in the current environment",
1270                    kind.to_ident()
1271                ),
1272                labels: vec![(
1273                    span,
1274                    "unsupported enable-extension".into(),
1275                )],
1276                notes: vec![],
1277            },
1278            Error::LanguageExtensionNotYetImplemented { kind, span } => ParseError {
1279                message: format!(
1280                    "the `{}` language extension is not yet supported",
1281                    LanguageExtension::Unimplemented(kind).to_ident()
1282                ),
1283                labels: vec![(span, "".into())],
1284                notes: vec![format!(
1285                    concat!(
1286                        "Let Naga maintainers know that you ran into this at ",
1287                        "<https://github.com/gfx-rs/wgpu/issues/{}>, ",
1288                        "so they can prioritize it!"
1289                    ),
1290                    kind.tracking_issue_num()
1291                )],
1292            },
1293            Error::DiagnosticInvalidSeverity {
1294                severity_control_name_span,
1295            } => ParseError {
1296                message: "invalid `diagnostic(…)` severity".into(),
1297                labels: vec![(
1298                    severity_control_name_span,
1299                    "not a valid severity level".into(),
1300                )],
1301                notes: vec![concat!(
1302                    "See available severities at ",
1303                    "<https://www.w3.org/TR/WGSL/#diagnostic-severity>."
1304                )
1305                .into()],
1306            },
1307            Error::DiagnosticDuplicateTriggeringRule(ConflictingDiagnosticRuleError {
1308                triggering_rule_spans,
1309            }) => {
1310                let [first_span, second_span] = triggering_rule_spans;
1311                ParseError {
1312                    message: "found conflicting `diagnostic(…)` rule(s)".into(),
1313                    labels: vec![
1314                        (first_span, "first rule".into()),
1315                        (second_span, "second rule".into()),
1316                    ],
1317                    notes: vec![
1318                        concat!(
1319                            "Multiple `diagnostic(…)` rules with the same rule name ",
1320                            "conflict unless they are directives and the severity is the same.",
1321                        )
1322                        .into(),
1323                        "You should delete the rule you don't want.".into(),
1324                    ],
1325                }
1326            }
1327            Error::DiagnosticAttributeNotYetImplementedAtParseSite {
1328                site_name_plural,
1329                ref spans,
1330            } => ParseError {
1331                message: "`@diagnostic(…)` attribute(s) not yet implemented".into(),
1332                labels: {
1333                    let mut spans = spans.iter().cloned();
1334                    let first = spans
1335                        .next()
1336                        .map(|span| {
1337                            (
1338                                span,
1339                                format!("can't use this on {site_name_plural} (yet)").into(),
1340                            )
1341                        })
1342                        .expect("internal error: diag. attr. rejection on empty map");
1343                    core::iter::once(first)
1344                        .chain(spans.map(|span| (span, "".into())))
1345                        .collect()
1346                },
1347                notes: vec![format!(concat!(
1348                    "Let Naga maintainers know that you ran into this at ",
1349                    "<https://github.com/gfx-rs/wgpu/issues/5320>, ",
1350                    "so they can prioritize it!"
1351                ))],
1352            },
1353            Error::DiagnosticAttributeNotSupported { on_what, ref spans } => {
1354                // In this case the user may have intended to create a global diagnostic filter directive,
1355                // so display a note to them suggesting the correct syntax.
1356                let intended_diagnostic_directive = match on_what {
1357                    DiagnosticAttributeNotSupportedPosition::SemicolonInModulePosition => true,
1358                    DiagnosticAttributeNotSupportedPosition::Other { .. } => false,
1359                };
1360                let on_what_plural = match on_what {
1361                    DiagnosticAttributeNotSupportedPosition::SemicolonInModulePosition => {
1362                        "semicolons"
1363                    }
1364                    DiagnosticAttributeNotSupportedPosition::Other { display_plural } => {
1365                        display_plural
1366                    }
1367                };
1368                ParseError {
1369                    message: format!(
1370                        "`@diagnostic(…)` attribute(s) on {on_what_plural} are not supported",
1371                    ),
1372                    labels: spans
1373                        .iter()
1374                        .cloned()
1375                        .map(|span| (span, "".into()))
1376                        .collect(),
1377                    notes: vec![
1378                        concat!(
1379                            "`@diagnostic(…)` attributes are only permitted on `fn`s, ",
1380                            "some statements, and `switch`/`loop` bodies."
1381                        )
1382                        .into(),
1383                        {
1384                            if intended_diagnostic_directive {
1385                                concat!(
1386                                    "If you meant to declare a diagnostic filter that ",
1387                                    "applies to the entire module, move this line to ",
1388                                    "the top of the file and remove the `@` symbol."
1389                                )
1390                                .into()
1391                            } else {
1392                                concat!(
1393                                    "These attributes are well-formed, ",
1394                                    "you likely just need to move them."
1395                                )
1396                                .into()
1397                            }
1398                        },
1399                    ],
1400                }
1401            }
1402            Error::SelectUnexpectedArgumentType { arg_span, ref arg_type } => ParseError {
1403                message: "unexpected argument type for `select` call".into(),
1404                labels: vec![(arg_span, format!("this value of type {arg_type}").into())],
1405                notes: vec!["expected a scalar or a `vecN` of scalars".into()],
1406            },
1407            Error::SelectRejectAndAcceptHaveNoCommonType {
1408                reject_span,
1409                ref reject_type,
1410                accept_span,
1411                ref accept_type,
1412            } => ParseError {
1413                message: "type mismatch for reject and accept values in `select` call".into(),
1414                labels: vec![
1415                    (reject_span, format!("reject value of type {reject_type}").into()),
1416                    (accept_span, format!("accept value of type {accept_type}").into()),
1417                ],
1418                notes: vec![],
1419            },
1420            Error::ExpectedGlobalVariable { name_span } => ParseError {
1421                message: "expected global variable".to_string(),
1422                labels: vec![(name_span, "variable used here".into())],
1423                notes: vec![],
1424            },
1425            Error::StructMemberTooLarge { member_name_span } => ParseError {
1426                message: "struct member is too large".into(),
1427                labels: vec![(member_name_span, "this member exceeds the maximum size".into())],
1428                notes: vec![format!(
1429                    "the maximum size is {} bytes",
1430                    crate::valid::MAX_TYPE_SIZE
1431                )],
1432            },
1433            Error::TypeTooLarge { span } => ParseError {
1434                message: "type is too large".into(),
1435                labels: vec![(span, "this type exceeds the maximum size".into())],
1436                notes: vec![format!(
1437                    "the maximum size is {} bytes",
1438                    crate::valid::MAX_TYPE_SIZE
1439                )],
1440            },
1441            Error::UnderspecifiedCooperativeMatrix => ParseError {
1442                message: "cooperative matrix constructor is underspecified".into(),
1443                labels: vec![],
1444                notes: vec![format!("must be F32")],
1445            },
1446            Error::InvalidCooperativeLoadType(span) => ParseError {
1447                message: "cooperative load should have a generic type for coop_mat".into(),
1448                labels: vec![(span, "type needs the coop_mat<...>".into())],
1449                notes: vec![format!("must be a valid cooperative type")],
1450            },
1451            Error::UnsupportedCooperativeScalar(span) => ParseError {
1452                message: "cooperative scalar type is not supported".into(),
1453                labels: vec![(span, "type needs the scalar type specified".into())],
1454                notes: vec![format!("must be F32")],
1455            },
1456            Error::UnexpectedIdentForEnumerant(ident_span) => ParseError {
1457                message: format!(
1458                    "identifier `{}` resolves to a declaration",
1459                    &source[ident_span]
1460                ),
1461                labels: vec![(ident_span, "needs to resolve to a predeclared enumerant".into())],
1462                notes: vec![],
1463            },
1464            Error::UnexpectedExprForEnumerant(expr_span) => ParseError {
1465                message: "unexpected expression".to_string(),
1466                labels: vec![(expr_span, "needs to be an identifier resolving to a predeclared enumerant".into())],
1467                notes: vec![],
1468            },
1469            Error::UnusedArgsForTemplate(ref expr_spans) => ParseError {
1470                message: "unused expressions for template".to_string(),
1471                labels: expr_spans.iter().cloned().map(|span| -> (_, _){ (span, "unused".into()) }).collect(),
1472                notes: vec![],
1473            },
1474            Error::UnexpectedTemplate(span) => ParseError {
1475                message: "unexpected template".to_string(),
1476                labels: vec![(span, "expected identifier".into())],
1477                notes: vec![],
1478            },
1479            Error::MissingTemplateArg {
1480                span,
1481                description: arg,
1482            } => ParseError {
1483                message: format!(
1484                    "`{}` needs a template argument specified: {arg}",
1485                    &source[span]
1486                ),
1487                labels: vec![(span, "is missing a template argument".into())],
1488                notes: vec![],
1489            },
1490            Error::UnexpectedExprForTypeExpression(expr_span) => ParseError {
1491                message: "unexpected expression".to_string(),
1492                labels: vec![(expr_span, "needs to be an identifier resolving to a type declaration (alias or struct) or predeclared type(-generator)".into())],
1493                notes: vec![],
1494            },
1495            Error::MissingIncomingPayload(span) => ParseError {
1496                message: "incoming payload is missing on a `closest_hit`, `any_hit` or `miss` shader entry point".to_string(),
1497                labels: vec![(
1498                    span,
1499                    "must be paired with a `@incoming_payload` attribute".into(),
1500                )],
1501                notes: vec![],
1502            },
1503        }
1504    }
1505}
naga/front/wgsl/error.rs

naga/front/wgsl/
error.rs
