Preprocess: handle new Ranges placeholder links

PeterFeicht · PeterFeicht · commit a3f556ca534e · 2018-08-24T08:09:35.000+02:00
The site uses placeholder links that get replaced by JS to point to
either Ranges TS or standard Ranges pages, depending on whether they are
used on Ranges TS pages or not. This is necessary because the links are
generated by the syntax highlighter, which doesn't know about the
different targets. This change adds handling of those placeholder links
to replace them by proper relative links.
diff --git a/commands/preprocess.py b/commands/preprocess.py
@@ -173,6 +173,28 @@ def transform_loader_link(target, file, root):
     abstarget = os.path.join(root, "common/" + convert_loader_name(target))
     return os.path.relpath(abstarget, os.path.dirname(file))
 
+def is_ranges_placeholder(target):
+    if re.match(r'https?://[a-z]+\.cppreference\.com/w/cpp/ranges(-[a-z]+)?-placeholder/.+', target):
+        return True
+    return False
+
+def transform_ranges_placeholder(target, file, root):
+    ranges = 'cpp/experimental/ranges' in file
+    repl = (r'\1/cpp/experimental/ranges/\2' if ranges else r'\1/cpp/\2')
+
+    if 'ranges-placeholder' in target:
+        match = r'https?://([a-z]+)\.cppreference\.com/w/cpp/ranges-placeholder/(.+)'
+    else:
+        match = r'https?://([a-z]+)\.cppreference\.com/w/cpp/ranges-([a-z]+)-placeholder/(.+)'
+        repl += (r'/\3' if ranges else r'/ranges/\3')
+
+    # Turn absolute placeholder link into site-relative link
+    reltarget = re.sub(match, repl + '.html', target)
+
+    # Make site-relative link file-relative
+    abstarget = os.path.join(root, reltarget)
+    return os.path.relpath(abstarget, os.path.dirname(file))
+
 def is_external_link(target):
     external_link_patterns = [
         'http://',
@@ -203,6 +225,9 @@ def transform_link(rename_map, target, file, root):
     if is_loader_link(target):
         return transform_loader_link(target, file, root)
 
+    if is_ranges_placeholder(target):
+        return transform_ranges_placeholder(target, file, root)
+
     if is_external_link(target):
         return target
 
