Fix precedence of comments vs '/' operator

examples/grammars/golang.cc

@@ -161,6 +161,9 @@ namespace tree_sitter_examples {
         { "type_name", sym("_identifier") },
         { "_identifier", pattern("\\a[\\w_]*") },
         { "number", pattern("\\d+(\\.\\d+)?") },
-        { "comment", pattern("//[^\n]*") },
+        
+        // TODO - make it clear how this number relates to the
+        // precedence used by the `keyword` helper.
+        { "comment", token(prec(1000, pattern("//[^\n]*"))) },
     }).ubiquitous_tokens({ "comment" });
 }

examples/parsers/json.c

@@ -322,6 +322,7 @@ LEX_FN() {
                 ADVANCE(27);
             LEX_ERROR();
         case ts_lex_state_error:
+            START_TOKEN();
             if (lookahead == '\0')
                 ADVANCE(25);
             if (('\t' <= lookahead && lookahead <= '\n') ||

spec/compiler/build_tables/get_metadata_spec.cc

@@ -10,12 +10,15 @@ START_TEST
 describe("getting metadata for rules", []() {
     MetadataKey key1 = MetadataKey(100);
     MetadataKey key2 = MetadataKey(101);
+    rule_ptr rule;
 
     describe("when given a metadata rule", [&]() {
-        auto rule = make_shared<Metadata>(sym("x"), map<MetadataKey, int>({
-            { key1, 1 },
-            { key2, 2 },
-        }));
+        before_each([&]() {
+            rule = make_shared<Metadata>(sym("x"), map<MetadataKey, int>({
+                { key1, 1 },
+                { key2, 2 },
+            }));
+        });
 
         it("returns the value for the given key", [&]() {
             AssertThat(get_metadata(rule, key1), Equals(1));
@@ -23,7 +26,17 @@ describe("getting metadata for rules", []() {
         });
 
         it("returns 0 if the rule does not have the key", [&]() {
-            AssertThat(get_metadata(rule, MetadataKey(3)), Equals(0));
+            AssertThat(get_metadata(rule, MetadataKey(0)), Equals(0));
+        });
+        
+        describe("when the rule contains another metadata rule", [&]() {
+            it("also gets metadata from the inner metadata rule", [&]() {
+                rule = make_shared<Metadata>(make_shared<Metadata>(sym("x"), map<MetadataKey, int>({
+                    { key1, 1 }
+                })), map<MetadataKey, int>());
+                
+                AssertThat(get_metadata(rule, key1), Equals(1));
+            });
         });
     });
 

spec/runtime/languages/golang/declarations.txt

@@ -31,7 +31,7 @@ parses comments
 ==========================================
 package trivial
 
-var x = 1 // on package
+var x = 1 // on variable
 
 func main() {
     // in function

src/compiler/build_tables/get_metadata.cc

@@ -9,7 +9,8 @@ namespace tree_sitter {
                 rules::MetadataKey metadata_key;
 
                 int apply_to(const rules::Metadata *rule) {
-                    return rule->value_for(metadata_key);
+                    int result = rule->value_for(metadata_key);
+                    return (result != 0) ? result : apply(rule->rule);
                 }
 
                 // TODO -