Sync the `global_decl` grammar rule

This Cl updates the parser implementation of the `global_decl` rule.
The `type_alias` rule is renamed to `type_alias_decl` and the `struct`
parsing is moved out of the synchronization to `;` code as a `struct`
no longer has a trailling `;`.

Bug: tint:1633
Change-Id: I44b25035cbe0ea0963ec73400986205e1623060e
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/98065
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Auto-Submit: Dan Sinclair <dsinclair@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>

src/tint/reader/wgsl/parser_impl.cc

@@ -440,7 +440,7 @@ Maybe<bool> ParserImpl::enable_directive() {
 //  : SEMICOLON
 //  | global_variable_decl SEMICOLON
 //  | global_constant_decl SEMICOLON
-//  | type_alias SEMICOLON
+//  | type_alias_decl SEMICOLON
 //  | struct_decl
 //  | function_decl
 //  | static_assert_statement SEMICOLON
@@ -450,7 +450,6 @@ Maybe<bool> ParserImpl::global_decl() {
     }
 
     bool errored = false;
-
     auto attrs = attribute_list();
     if (attrs.errored) {
         errored = true;
@@ -490,7 +489,7 @@ Maybe<bool> ParserImpl::global_decl() {
             return true;
         }
 
-        auto ta = type_alias();
+        auto ta = type_alias_decl();
         if (ta.errored) {
             return Failure::kErrored;
         }
@@ -503,15 +502,6 @@ Maybe<bool> ParserImpl::global_decl() {
             return true;
         }
 
-        auto str = struct_decl();
-        if (str.errored) {
-            return Failure::kErrored;
-        }
-        if (str.matched) {
-            builder_.AST().AddTypeDecl(str.value);
-            return true;
-        }
-
         auto assertion = static_assert_stmt();
         if (assertion.errored) {
             return Failure::kErrored;
@@ -534,6 +524,15 @@ Maybe<bool> ParserImpl::global_decl() {
         return expect_attributes_consumed(attrs.value);
     }
 
+    auto str = struct_decl();
+    if (str.errored) {
+        errored = true;
+    }
+    if (str.matched) {
+        builder_.AST().AddTypeDecl(str.value);
+        return true;
+    }
+
     auto func = function_decl(attrs.value);
     if (func.errored) {
         errored = true;
@@ -1021,9 +1020,9 @@ Maybe<ParserImpl::VariableQualifier> ParserImpl::variable_qualifier() {
     return vq;
 }
 
-// type_alias
+// type_alias_decl
 //   : TYPE IDENT EQUAL type_decl
-Maybe<const ast::Alias*> ParserImpl::type_alias() {
+Maybe<const ast::Alias*> ParserImpl::type_alias_decl() {
     if (!peek_is(Token::Type::kType)) {
         return Failure::kNoMatch;
     }

src/tint/reader/wgsl/parser_impl.h

@@ -420,9 +420,9 @@ class ParserImpl {
     /// Parses a `variable_qualifier` grammar element
     /// @returns the variable qualifier information
     Maybe<VariableQualifier> variable_qualifier();
-    /// Parses a `type_alias` grammar element
+    /// Parses a `type_alias_decl` grammar element
     /// @returns the type alias or nullptr on error
-    Maybe<const ast::Alias*> type_alias();
+    Maybe<const ast::Alias*> type_alias_decl();
     /// Parses a `type_decl` grammar element
     /// @returns the parsed Type or nullptr if none matched.
     Maybe<const ast::Type*> type_decl();

src/tint/reader/wgsl/parser_impl_type_alias_test.cc

@@ -20,7 +20,7 @@ namespace {
 TEST_F(ParserImplTest, TypeDecl_ParsesType) {
     auto p = parser("type a = i32");
 
-    auto t = p->type_alias();
+    auto t = p->type_alias_decl();
     EXPECT_FALSE(p->has_error());
     EXPECT_FALSE(t.errored);
     EXPECT_TRUE(t.matched);
@@ -35,7 +35,7 @@ TEST_F(ParserImplTest, TypeDecl_ParsesType) {
 TEST_F(ParserImplTest, TypeDecl_Parses_Ident) {
     auto p = parser("type a = B");
 
-    auto t = p->type_alias();
+    auto t = p->type_alias_decl();
     EXPECT_FALSE(p->has_error());
     EXPECT_FALSE(t.errored);
     EXPECT_TRUE(t.matched);
@@ -54,7 +54,7 @@ TEST_F(ParserImplTest, TypeDecl_Unicode_Parses_Ident) {
 
     auto p = parser("type " + ident + " = i32");
 
-    auto t = p->type_alias();
+    auto t = p->type_alias_decl();
     EXPECT_FALSE(p->has_error());
     EXPECT_FALSE(t.errored);
     EXPECT_TRUE(t.matched);
@@ -68,7 +68,7 @@ TEST_F(ParserImplTest, TypeDecl_Unicode_Parses_Ident) {
 
 TEST_F(ParserImplTest, TypeDecl_MissingIdent) {
     auto p = parser("type = i32");
-    auto t = p->type_alias();
+    auto t = p->type_alias_decl();
     EXPECT_TRUE(t.errored);
     EXPECT_FALSE(t.matched);
     EXPECT_TRUE(p->has_error());
@@ -78,7 +78,7 @@ TEST_F(ParserImplTest, TypeDecl_MissingIdent) {
 
 TEST_F(ParserImplTest, TypeDecl_InvalidIdent) {
     auto p = parser("type 123 = i32");
-    auto t = p->type_alias();
+    auto t = p->type_alias_decl();
     EXPECT_TRUE(t.errored);
     EXPECT_FALSE(t.matched);
     EXPECT_TRUE(p->has_error());
@@ -88,7 +88,7 @@ TEST_F(ParserImplTest, TypeDecl_InvalidIdent) {
 
 TEST_F(ParserImplTest, TypeDecl_MissingEqual) {
     auto p = parser("type a i32");
-    auto t = p->type_alias();
+    auto t = p->type_alias_decl();
     EXPECT_TRUE(t.errored);
     EXPECT_FALSE(t.matched);
     EXPECT_TRUE(p->has_error());