reader/wsgl: Improve error message for missing 'var'
Fixes: tint:295
Change-Id: Id01ad61fa24f14a1d86ca945d941fd27ee1e8f82
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/33400
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: dan sinclair <dsinclair@chromium.org>
diff --git a/src/reader/wgsl/parser_impl.cc b/src/reader/wgsl/parser_impl.cc
index 0d6f4d5..8773fd0 100644
--- a/src/reader/wgsl/parser_impl.cc
+++ b/src/reader/wgsl/parser_impl.cc
@@ -2577,6 +2577,14 @@
auto t = peek();
auto source = t.source();
+ // tint:295 - Test for `ident COLON` - this is invalid grammar, and without
+ // special casing will error as "missing = for assignment", which is less
+ // helpful than this error message:
+ if (peek(0).IsIdentifier() && peek(1).IsColon()) {
+ return add_error(peek(0).source(),
+ "expected 'var' for variable declaration");
+ }
+
auto lhs = unary_expression();
if (lhs.errored)
return Failure::kErrored;
diff --git a/src/reader/wgsl/parser_impl_error_msg_test.cc b/src/reader/wgsl/parser_impl_error_msg_test.cc
index 8a5c15d..cf5906b 100644
--- a/src/reader/wgsl/parser_impl_error_msg_test.cc
+++ b/src/reader/wgsl/parser_impl_error_msg_test.cc
@@ -70,9 +70,9 @@
TEST_F(ParserImplErrorTest, AssignmentStmtMissingAssignment2) {
EXPECT("fn f() -> void { a : i32; }",
- "test.wgsl:1:20 error: expected '=' for assignment\n"
+ "test.wgsl:1:18 error: expected 'var' for variable declaration\n"
"fn f() -> void { a : i32; }\n"
- " ^\n");
+ " ^\n");
}
TEST_F(ParserImplErrorTest, AssignmentStmtMissingSemicolon) {
@@ -216,6 +216,13 @@
" ^\n");
}
+TEST_F(ParserImplErrorTest, ForLoopInitializerMissingVar) {
+ EXPECT("fn f() -> void { for (i : i32 = 0; i < 8; i=i+1) {} }",
+ "test.wgsl:1:23 error: expected 'var' for variable declaration\n"
+ "fn f() -> void { for (i : i32 = 0; i < 8; i=i+1) {} }\n"
+ " ^\n");
+}
+
TEST_F(ParserImplErrorTest, ForLoopConditionMissingSemicolon) {
EXPECT("fn f() -> void { for (var i : i32 = 0; i < 8 i=i+1) {} }",
"test.wgsl:1:46 error: expected ';' for condition in for loop\n"
