Rollup merge of rust-lang#4229 - euclio:lint-doc-generation-fix, r=flip1995

don't strip blank lines in lint documentation

changelog: don't strip blank lines in lint documentation

Fixes rust-lang#4116.

This PR also switches the docs headings to deterministically display in the order that they are declared in the source, with "Configuration" always appearing last. It doesn't seem like there was a defined order before.

Author: flip1995

util/export.py

@@ -2,6 +2,7 @@
 
 # Build the gh-pages
 
+from collections import OrderedDict
 import re
 import sys
 import json
@@ -21,33 +22,29 @@ def parse_lint_def(lint):
     lint_dict['id'] = lint.name
     lint_dict['group'] = lint.group
     lint_dict['level'] = lint.level
-    lint_dict['docs'] = {}
+    lint_dict['docs'] = OrderedDict()
 
     last_section = None
 
     for line in lint.doc:
-        if len(line.strip()) == 0 and not last_section.startswith("Example"):
-            continue
-
         match = re.match(lint_subheadline, line)
         if match:
             last_section = match.groups()[0]
-        if match:
             text = match.groups()[1]
         else:
             text = line
 
         if not last_section:
-            log.warn("Skipping comment line as it was not preceded by a heading")
+            log.warning("Skipping comment line as it was not preceded by a heading")
             log.debug("in lint `%s`, line `%s`", lint.name, line)
 
-        fragment = lint_dict['docs'].get(last_section, "")
-        if text == "\n":
-            line = fragment + text
-        else:
-            line = (fragment + "\n" + text).strip()
+        if last_section not in lint_dict['docs']:
+            lint_dict['docs'][last_section] = ""
+
+        lint_dict['docs'][last_section] += text + "\n"
 
-        lint_dict['docs'][last_section] = line
+    for section in lint_dict['docs']:
+        lint_dict['docs'][section] = lint_dict['docs'][section].strip()
 
     return lint_dict