Bug 1178955 - Error when semicolon comments are seen; r=smacleod

configobj doesn't support semicolon comments. Why, I don't know, since
they are pretty common in ini files.

Do a static check for semicolon comments and print a more actionable
error message.

--HG--
extra : commitid : CULjsg4do9Z
extra : rebase_source : f135cc726462c73a8363ebb8c98092177cf7ffd3
extra : amend_source : 0b8c67d5b0be3bc07cf7ff4f136bb58d342368c4

tools/mercurial/hgsetup/config.py

@@ -30,7 +30,7 @@ def config_file(files):
     return files[0]
 
 
-class HgIncludeException(Exception):
+class ParseException(Exception):
     pass
 
 
@@ -49,8 +49,12 @@ class MercurialConfig(object):
             with codecs.open(path, 'r', encoding='utf-8') as f:
                 for line in f:
                     if line.startswith('%include'):
-                        raise HgIncludeException(
+                        raise ParseException(
                             '%include directive is not supported by MercurialConfig')
+                    if line.startswith(';'):
+                        raise ParseException(
+                            'semicolon (;) comments are not supported; '
+                            'use # instead')
 
         # write_empty_values is necessary to prevent built-in extensions (which
         # have no value) from being dropped on write.

tools/mercurial/hgsetup/wizard.py

@@ -22,8 +22,8 @@ from mozversioncontrol import get_hg_version
 from .update import MercurialUpdater
 from .config import (
     config_file,
-    HgIncludeException,
     MercurialConfig,
+    ParseException,
 )
 
 
@@ -227,7 +227,7 @@ class MercurialSetupWizard(object):
                 print(error.message)
 
             return 1
-        except HgIncludeException as e:
+        except ParseException as e:
             print('Error importing existing Mercurial config: %s\n' % config_path)
             print(e.message)