[include-mapping] Fix parsing of html_book_20190607.zip (https://en.cppreference.com/w/File:html_book_20190607.zip). Skip entries that have been added to the index (C++20 symbols), but the corresponding pages for which have not been created yet.

[hokein]

clang/tools/include-mapping/cppreference_parser.py

118

so the input path can be invalid, pointing to a non-existing file, I'd just check it in the caller side, see my other comment.

144

I think just adding a file-existing check would work:

if os.path.isfile(path):
   results.append((symbol_name,
                      pool.apply_async(_ReadSymbolPage, (path, symbol_name))))

[VitaNuo]

Address review comments.

[VitaNuo]

Thanks for the review!

clang/tools/include-mapping/cppreference_parser.py

118

good idea!

[kadircet]

clang/tools/include-mapping/cppreference_parser.py

145

sorry for being late to the party, but can you also print an error in the case we're dropping the symbol?

[VitaNuo]

clang/tools/include-mapping/cppreference_parser.py

145

https://reviews.llvm.org/D141611

clang/tools/include-mapping/cppreference_parser.py

for symbol_href in soup.select("a[title]"):
     if symbol_tt:
       symbols.append((symbol_tt.text.rstrip("<>()"), # strip any trailing <>()
                       symbol_href["href"], variant))
   return symbols
 
 
 def _ReadSymbolPage(path, name):
   with open(path) as f:
     return _ParseSymbolPage(f.read(), name)
 
 
 def _GetSymbols(pool, root_dir, index_page_name, namespace, variants_to_accept):
   """Get all symbols listed in the index page. All symbols should be in the
   given namespace.
 
   Returns a list of Symbols.
   """
with open(index_page_path, "r") as f:
     results = [] # (symbol_name, promise of [header...])
     for symbol_name, symbol_page_path, variant in _ParseIndexPage(f.read()):
       # Variant symbols (e.g. the std::locale version of isalpha) add ambiguity.
       # FIXME: use these as a fallback rather than ignoring entirely.
       variants_for_symbol = variants_to_accept.get(
           (namespace or "") + symbol_name, ())
       if variant and variant not in variants_for_symbol:
         continue
       path = os.path.join(root_dir, symbol_page_path)
+      if os.path.isfile(path):
         results.append((symbol_name,
                       pool.apply_async(_ReadSymbolPage, (path, symbol_name))))
 
     # Build map from symbol name to a set of headers.
     symbol_headers = collections.defaultdict(set)
     for symbol_name, lazy_headers in results:
       symbol_headers[symbol_name].update(lazy_headers.get())
 
   symbols = []