#16245: add a script to generate the html.entities.html5 dict.

1 files changed, 105 insertions, 0 deletions

diff --git a/Tools/scripts/parse_html5_entities.py b/Tools/scripts/parse_html5_entities.py
new file mode 100644
index 0000000..c011328
--- /dev/null
+++ b/Tools/scripts/parse_html5_entities.py
@@ -0,0 +1,105 @@
+#!/usr/bin/env python3
+"""
+Utility for parsing HTML5 entity definitions available from:
+
+    http://dev.w3.org/html5/spec/entities.json
+
+Written by Ezio Melotti and Iuliia Proskurnia.
+
+"""
+
+import os
+import sys
+import json
+from urllib.request import urlopen
+from html.entities import html5
+
+entities_url = 'http://dev.w3.org/html5/spec/entities.json'
+
+def get_json(url):
+    """Download the json file from the url and returns a decoded object."""
+    with urlopen(url) as f:
+        data = f.read().decode('utf-8')
+    return json.loads(data)
+
+def create_dict(entities):
+    """Create the html5 dict from the decoded json object."""
+    new_html5 = {}
+    for name, value in entities.items():
+        new_html5[name.lstrip('&')] = value['characters']
+    return new_html5
+
+def compare_dicts(old, new):
+    """Compare the old and new dicts and print the differences."""
+    added = new.keys() - old.keys()
+    if added:
+        print('{} entitie(s) have been added:'.format(len(added)))
+        for name in sorted(added):
+            print('  {!r}: {!r}'.format(name, new[name]))
+    removed = old.keys() - new.keys()
+    if removed:
+        print('{} entitie(s) have been removed:'.format(len(removed)))
+        for name in sorted(removed):
+            print('  {!r}: {!r}'.format(name, old[name]))
+    changed = set()
+    for name in (old.keys() & new.keys()):
+        if old[name] != new[name]:
+            changed.add((name, old[name], new[name]))
+    if changed:
+        print('{} entitie(s) have been modified:'.format(len(changed)))
+        for item in sorted(changed):
+            print('  {!r}: {!r} -> {!r}'.format(*item))
+
+def write_items(entities, file=sys.stdout):
+    """Write the items of the dictionary in the specified file."""
+    # The keys in the generated dictionary should be sorted
+    # in a case-insensitive way, however, when two keys are equal,
+    # the uppercase version should come first so that the result
+    # looks like: ['Aacute', 'aacute', 'Aacute;', 'aacute;', ...]
+    # To do this we first sort in a case-sensitive way (so all the
+    # uppercase chars come first) and then sort with key=str.lower.
+    # Since the sorting is stable the uppercase keys will eventually
+    # be before their equivalent lowercase version.
+    keys = sorted(entities.keys())
+    keys = sorted(keys, key=str.lower)
+    print('html5 = {', file=file)
+    for name in keys:
+        print('    {!r}: {!a},'.format(name, entities[name]), file=file)
+    print('}', file=file)
+
+
+if __name__ == '__main__':
+    # without args print a diff between html.entities.html5 and new_html5
+    # with --create print the new html5 dict
+    # with --patch patch the Lib/html/entities.py file
+    new_html5 = create_dict(get_json(entities_url))
+    if '--create' in sys.argv:
+        print('# map the HTML5 named character references to the '
+              'equivalent Unicode character(s)')
+        print('# Generated by {}.  Do not edit manually.'.format(__file__))
+        write_items(new_html5)
+    elif '--patch' in sys.argv:
+        fname = 'Lib/html/entities.py'
+        temp_fname = fname + '.temp'
+        with open(fname) as f1, open(temp_fname, 'w') as f2:
+            skip = False
+            for line in f1:
+                if line.startswith('html5 = {'):
+                    write_items(new_html5, file=f2)
+                    skip = True
+                    continue
+                if skip:
+                    # skip the old items until the }
+                    if line.startswith('}'):
+                        skip = False
+                    continue
+                f2.write(line)
+        os.remove(fname)
+        os.rename(temp_fname, fname)
+    else:
+        if html5 == new_html5:
+            print('The current dictionary is updated.')
+        else:
+            compare_dicts(html5, new_html5)
+            print('Run "./python {0} --patch" to update Lib/html/entities.html '
+                  'or "./python {0} --create" to see the generated ' 'dictionary.'.format(__file__))