Add 'allowDuplicates' flag to json5 files for make_names.py

If a json5 file for make_names.py contains duplicated names, make_name.py
produced invalid C++ code and we had to remove duplicates.

* make_names.py should report an error for duplicated entries instead of
  producing invalid code.

* html/keywords.json5 should allow duplicated entries because it
  contains keyword sets for multiple attributes and some keywords are
  valid for multiple attributes.

Change-Id: I81c2a4a978ece5a03471fd8b37d85b61cda2a8e3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2032465
Commit-Queue: Kent Tamura <tkent@chromium.org>
Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#737211}

third_party/blink/renderer/build/scripts/json5_generator.py

@@ -216,6 +216,31 @@ class Json5File(object):
         self._process(doc)
 
 
+def reject_duplicates(entries):
+    assert isinstance(entries, list), 'The data should be a list.'
+    name_dict = {}
+    for entry in entries:
+        name = entry['name'].original
+        if name in name_dict:
+            raise Exception('The data contains multiple entries for "%s".' % name)
+        name_dict[name] = entry
+
+
+def remove_duplicates(entries):
+    assert isinstance(entries, list), 'The data should be a list.'
+    name_dict = {}
+    filtered_list = []
+    for entry in entries:
+        name = entry['name'].original
+        if name in name_dict:
+            if entry != name_dict[name]:
+                raise Exception('Duplicated entries for "%s" must be identical.' % name)
+        else:
+            name_dict[name] = entry
+            filtered_list.append(entry)
+    return filtered_list
+
+
 class Writer(object):
     # Subclasses should override.
     class_name = None

third_party/blink/renderer/build/scripts/make_names.py

@@ -52,6 +52,7 @@ class MakeNamesWriter(json5_generator.Writer):
         'Symbol': {},
     }
     default_metadata = {
+        'allowDuplicates': False,
         'export': '',
         'namespace': '',
         'suffix': '',
@@ -77,6 +78,12 @@ class MakeNamesWriter(json5_generator.Writer):
                              '"%s" is specified in %s.' %
                              (namespace, json5_file_path))
 
+        entries = self.json5_file.name_dictionaries
+        if self.json5_file.metadata['allowDuplicates']:
+            entries = json5_generator.remove_duplicates(entries)
+        else:
+            json5_generator.reject_duplicates(entries)
+
         basename, _ = os.path.splitext(os.path.basename(json5_file_path[0]))
         self._outputs = {
             (basename + '.h'): self.generate_header,
@@ -87,7 +94,7 @@ class MakeNamesWriter(json5_generator.Writer):
             'namespace': namespace,
             'suffix': suffix,
             'export': export,
-            'entries': self.json5_file.name_dictionaries,
+            'entries': entries,
             'header_guard': self.make_header_guard(qualified_header),
             'input_files': self._input_files,
             'this_include_path': qualified_header,

third_party/blink/renderer/core/html/keywords.json5

@@ -6,6 +6,7 @@
   metadata: {
     namespace: "keywords",
     export: "CORE_EXPORT",
+    allowDuplicates: true,
   },
 
   data: [
@@ -48,7 +49,7 @@
     // https://wicg.github.io/priority-hints/#solution-0
     "high",
     "low",
-    // "auto",
+    "auto",
 
     // inputmode attribute
     // https://html.spec.whatwg.org/C/#attr-inputmode
@@ -59,7 +60,7 @@
     "email",
     "numeric",
     "decimal",
-    // "search",
+    "search",
 
     // invisible attribute
     // https://github.com/rakina/searchable-invisible-dom
@@ -70,7 +71,7 @@
     // https://github.com/scott-little/lazyload#ways-the-loading-attribute-can-be-used
     "lazy",
     "eager",
-    // "auto",
+    "auto",
 
     // referrerpolicy attribute
     // https://w3c.github.io/webappsec-referrer-policy/#referrer-policies