Revert of Don't require DEPS OWNERS when moving lines around in a DEPS file.

PRESUBMIT.py

Index: PRESUBMIT.py
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 23d78673850c0303d74de9b5e6cb91c4b29e0f9f..16f00ad5bff741fd78119cda7f62031447597c1d 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -1049,57 +1049,7 @@
   return results
 
 
-def _ExtractAddRulesFromParsedDeps(parsed_deps):
-  """Extract the rules that add dependencies from a parsed DEPS file.
-
-  Args:
-    parsed_deps: the locals dictionary from evaluating the DEPS file."""
-  add_rules = set()
-  add_rules.update([
-      rule[1:] for rule in parsed_deps.get('include_rules', [])
-      if rule.startswith('+') or rule.startswith('!')
-  ])
-  for specific_file, rules in parsed_deps.get('specific_include_rules',
-                                              {}).iteritems():
-    add_rules.update([
-        rule[1:] for rule in rules
-        if rule.startswith('+') or rule.startswith('!')
-    ])
-  return add_rules
-
-
-def _ParseDeps(contents):
-  """Simple helper for parsing DEPS files."""
-  # Stubs for handling special syntax in the root DEPS file.
-  def FromImpl(*_):
-    pass  # NOP function so "From" doesn't fail.
-
-  def FileImpl(_):
-    pass  # NOP function so "File" doesn't fail.
-
-  class _VarImpl:
-
-    def __init__(self, local_scope):
-      self._local_scope = local_scope
-
-    def Lookup(self, var_name):
-      """Implements the Var syntax."""
-      try:
-        return self._local_scope['vars'][var_name]
-      except KeyError:
-        raise Exception('Var is not defined: %s' % var_name)
-
-  local_scope = {}
-  global_scope = {
-      'File': FileImpl,
-      'From': FromImpl,
-      'Var': _VarImpl(local_scope).Lookup,
-  }
-  exec contents in global_scope, local_scope
-  return local_scope
-
-
-def _CalculateAddedDeps(os_path, old_contents, new_contents):
+def _FilesToCheckForIncomingDeps(re, changed_lines):
   """Helper method for _CheckAddedDepsHaveTargetApprovals. Returns
   a set of DEPS entries that we should look up.
 
@@ -1110,20 +1060,22 @@
   # We ignore deps entries on auto-generated directories.
   AUTO_GENERATED_DIRS = ['grit', 'jni']
 
-  old_deps = _ExtractAddRulesFromParsedDeps(_ParseDeps(old_contents))
-  new_deps = _ExtractAddRulesFromParsedDeps(_ParseDeps(new_contents))
-
-  added_deps = new_deps.difference(old_deps)
-
+  # This pattern grabs the path without basename in the first
+  # parentheses, and the basename (if present) in the second. It
+  # relies on the simple heuristic that if there is a basename it will
+  # be a header file ending in ".h".
+  pattern = re.compile(
+      r"""['"]\+([^'"]+?)(/[a-zA-Z0-9_]+\.h)?['"].*""")
   results = set()
-  for added_dep in added_deps:
-    if added_dep.split('/')[0] in AUTO_GENERATED_DIRS:
-      continue
-    # Assume that a rule that ends in .h is a rule for a specific file.
-    if added_dep.endswith('.h'):
-      results.add(added_dep)
-    else:
-      results.add(os_path.join(added_dep, 'DEPS'))
+  for changed_line in changed_lines:
+    m = pattern.match(changed_line)
+    if m:
+      path = m.group(1)
+      if path.split('/')[0] not in AUTO_GENERATED_DIRS:
+        if m.group(2):
+          results.add('%s%s' % (path, m.group(2)))
+        else:
+          results.add('%s/DEPS' % path)
   return results
 
 
@@ -1133,7 +1085,7 @@
   target file or directory, to avoid layering violations from being
   introduced. This check verifies that this happens.
   """
-  virtual_depended_on_files = set()
+  changed_lines = set()
 
   file_filter = lambda f: not input_api.re.match(
       r"^third_party[\\\/]WebKit[\\\/].*", f.LocalPath())
@@ -1141,11 +1093,14 @@
                                    file_filter=file_filter):
     filename = input_api.os_path.basename(f.LocalPath())
     if filename == 'DEPS':
-      virtual_depended_on_files.update(_CalculateAddedDeps(
-          input_api.os_path,
-          '\n'.join(f.OldContents()),
-          '\n'.join(f.NewContents())))
-
+      changed_lines |= set(line.strip()
+                           for line_num, line
+                           in f.ChangedContents())
+  if not changed_lines:
+    return []
+
+  virtual_depended_on_files = _FilesToCheckForIncomingDeps(input_api.re,
+                                                           changed_lines)
   if not virtual_depended_on_files:
     return []