From 16edcf9b034f7b8d5629e807185e3c295aae6c28 Mon Sep 17 00:00:00 2001
From: Ben Clayton <bclayton@google.com>
Date: Tue, 31 Aug 2021 18:58:26 +0000
Subject: [PATCH] reader/wgsl: Error for unconsumed decorations

When applied to valid module-scope declarations.

Fixed: chromium:1244349
Change-Id: Icb19200cae751ac70974481693ecbcf48fd627f0
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/63160
Auto-Submit: Ben Clayton <bclayton@google.com>
Commit-Queue: James Price <jrprice@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: James Price <jrprice@google.com>
---
 src/reader/wgsl/parser_impl.cc                | 17 +++++++++------
 src/reader/wgsl/parser_impl_error_msg_test.cc | 21 ++++++++++++-------
 2 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/src/reader/wgsl/parser_impl.cc b/src/reader/wgsl/parser_impl.cc
index 18ae65656d..637375d8f1 100644
--- a/src/reader/wgsl/parser_impl.cc
+++ b/src/reader/wgsl/parser_impl.cc
@@ -427,27 +427,32 @@ Expect<bool> ParserImpl::expect_global_decl() {
     return Failure::kNoMatch;
   });
 
-  if (decl.errored)
+  if (decl.errored) {
     errored = true;
-  if (decl.matched)
-    return true;
+  }
+  if (decl.matched) {
+    return expect_decorations_consumed(decos.value);
+  }
 
   auto func = function_decl(decos.value);
-  if (func.errored)
+  if (func.errored) {
     errored = true;
+  }
   if (func.matched) {
     builder_.AST().AddFunction(func.value);
     return true;
   }
 
-  if (errored)
+  if (errored) {
     return Failure::kErrored;
+  }
 
   // Invalid syntax found - try and determine the best error message
 
   // We have decorations parsed, but nothing to consume them?
-  if (decos.value.size() > 0)
+  if (decos.value.size() > 0) {
     return add_error(next(), "expected declaration after decorations");
+  }
 
   // We have a statement outside of a function?
   auto t = peek();
diff --git a/src/reader/wgsl/parser_impl_error_msg_test.cc b/src/reader/wgsl/parser_impl_error_msg_test.cc
index 65e8eafdf3..07007b4857 100644
--- a/src/reader/wgsl/parser_impl_error_msg_test.cc
+++ b/src/reader/wgsl/parser_impl_error_msg_test.cc
@@ -51,6 +51,13 @@ TEST_F(ParserImplErrorTest, AndInvalidExpr) {
          "                    ^\n");
 }
 
+TEST_F(ParserImplErrorTest, AliasDeclInvalidDeco) {
+  EXPECT("[[block]]type e=u32;",
+         "test.wgsl:1:3 error: unexpected decorations\n"
+         "[[block]]type e=u32;\n"
+         "  ^^^^^\n");
+}
+
 TEST_F(ParserImplErrorTest, ArrayIndexExprInvalidExpr) {
   EXPECT("fn f() { x = y[^]; }",
          "test.wgsl:1:16 error: unable to parse expression inside []\n"
@@ -275,13 +282,6 @@ TEST_F(ParserImplErrorTest, ForLoopMissingRBrace) {
          "                                              ^\n");
 }
 
-TEST_F(ParserImplErrorTest, FunctionDeclInvalid) {
-  EXPECT("[[stage(vertex)]] x;",
-         "test.wgsl:1:19 error: expected declaration after decorations\n"
-         "[[stage(vertex)]] x;\n"
-         "                  ^\n");
-}
-
 TEST_F(ParserImplErrorTest, FunctionDeclDecoMissingEnd) {
   EXPECT("[[stage(vertex) fn f() {}",
          "test.wgsl:1:17 error: expected ']]' for decoration list\n"
@@ -551,6 +551,13 @@ TEST_F(ParserImplErrorTest, GlobalDeclConstExprMissingRParen) {
          "                                  ^\n");
 }
 
+TEST_F(ParserImplErrorTest, GlobalDeclInvalidDeco) {
+  EXPECT("[[stage(vertex)]] x;",
+         "test.wgsl:1:19 error: expected declaration after decorations\n"
+         "[[stage(vertex)]] x;\n"
+         "                  ^\n");
+}
+
 TEST_F(ParserImplErrorTest, GlobalDeclSampledTextureMissingLessThan) {
   EXPECT("var x : texture_1d;",
          "test.wgsl:1:19 error: expected '<' for sampled texture type\n"