WIP: diag(naga): narrow "easy" ExpressionError labels to single expr.

TODO: Validate that these look as we want, preferably with tests!

Author: ErichDonGubler

naga/src/valid/expression.rs

@@ -147,22 +147,23 @@ pub enum ExpressionError {
 
 impl ExpressionError {
     pub(crate) fn expr_handles(&self) -> impl Iterator<Item = (Handle<crate::Expression>, String)> {
+        let just = |handle| vec![(handle, "".into())];
         match *self {
             Self::NotInScope => Vec::new(),
-            Self::InvalidBaseType(..) => Vec::new(),
-            Self::InvalidIndexType(..) => Vec::new(),
-            Self::NegativeIndex(..) => Vec::new(),
+            Self::InvalidBaseType(handle) => just(handle),
+            Self::InvalidIndexType(handle) => just(handle),
+            Self::NegativeIndex(handle) => just(handle),
             Self::IndexOutOfBounds(..) => Vec::new(),
             Self::FunctionArgumentDoesntExist(..) => Vec::new(),
-            Self::InvalidPointerType(..) => Vec::new(),
-            Self::InvalidArrayType(..) => Vec::new(),
-            Self::InvalidRayQueryType(..) => Vec::new(),
-            Self::InvalidSplatType(..) => Vec::new(),
-            Self::InvalidVectorType(..) => Vec::new(),
+            Self::InvalidPointerType(handle) => just(handle),
+            Self::InvalidArrayType(handle) => just(handle),
+            Self::InvalidRayQueryType(handle) => just(handle),
+            Self::InvalidSplatType(handle) => just(handle),
+            Self::InvalidVectorType(handle) => just(handle),
             Self::InvalidSwizzleComponent(..) => Vec::new(),
             Self::Compose(..) => Vec::new(),
             Self::IndexableLength(..) => Vec::new(),
-            Self::InvalidUnaryOperandType(..) => Vec::new(),
+            Self::InvalidUnaryOperandType(_unary_operator, handle) => just(handle),
             Self::InvalidBinaryOperandTypes { .. } => Vec::new(),
             Self::SelectValuesTypeMismatch {
                 accept,
@@ -179,8 +180,8 @@ impl ExpressionError {
             } => {
                 vec![(actual, format!("this is of type {actual_ty:?}"))]
             }
-            Self::InvalidBooleanVector(..) => Vec::new(),
-            Self::InvalidFloatArgument(..) => Vec::new(),
+            Self::InvalidBooleanVector(handle) => just(handle),
+            Self::InvalidFloatArgument(handle) => just(handle),
             Self::Type(..) => Vec::new(),
             Self::ExpectedGlobalVariable => Vec::new(),
             Self::ExpectedGlobalOrArgument => Vec::new(),
@@ -191,24 +192,24 @@ impl ExpressionError {
             Self::InvalidDerivative => Vec::new(),
             Self::InvalidImageArrayIndex => Vec::new(),
             Self::InvalidImageOtherIndex => Vec::new(),
-            Self::InvalidImageArrayIndexType(..) => Vec::new(),
-            Self::InvalidImageOtherIndexType(..) => Vec::new(),
-            Self::InvalidImageCoordinateType(..) => Vec::new(),
+            Self::InvalidImageArrayIndexType(handle) => just(handle),
+            Self::InvalidImageOtherIndexType(handle) => just(handle),
+            Self::InvalidImageCoordinateType(_image_dimension, handle) => just(handle),
             Self::ComparisonSamplingMismatch { .. } => Vec::new(),
             Self::InvalidSampleOffsetExprType => Vec::new(),
-            Self::InvalidSampleOffset(..) => Vec::new(),
-            Self::InvalidDepthReference(..) => Vec::new(),
+            Self::InvalidSampleOffset(_image_dimension, handle) => just(handle),
+            Self::InvalidDepthReference(handle) => just(handle),
             Self::InvalidDepthSampleLevel => Vec::new(),
             Self::InvalidGatherLevel => Vec::new(),
             Self::InvalidGatherComponent(..) => Vec::new(),
             Self::InvalidGatherDimension(..) => Vec::new(),
-            Self::InvalidSampleLevelExactType(..) => Vec::new(),
-            Self::InvalidSampleLevelBiasType(..) => Vec::new(),
+            Self::InvalidSampleLevelExactType(handle) => just(handle),
+            Self::InvalidSampleLevelBiasType(handle) => just(handle),
             Self::InvalidSampleLevelBiasDimension(..) => Vec::new(),
-            Self::InvalidSampleLevelGradientType(..) => Vec::new(),
+            Self::InvalidSampleLevelGradientType(_image_dimension, handle) => just(handle),
             Self::InvalidCastArgument => Vec::new(),
             Self::WrongArgumentCount(..) => Vec::new(),
-            Self::InvalidArgumentType(..) => Vec::new(),
+            Self::InvalidArgumentType(_math_function, _, handle) => just(handle),
             Self::InvalidWorkGroupUniformLoadResultType(..) => Vec::new(),
             Self::MissingCapabilities(..) => Vec::new(),
             Self::Literal(..) => Vec::new(),