Bug 1132771 - Implement file-info mach command; r=glandium

Now that we have a mechanism for defining file-based metadata, let's add
a mach command to interface with it.

Currently, we limit ourselves to simple Bugzilla data dumping. Features
will be added over time.

python/mozbuild/mozbuild/frontend/mach_commands.py

@@ -4,13 +4,17 @@
 
 from __future__ import print_function, unicode_literals
 
+from collections import defaultdict
+
 from mach.decorators import (
     CommandArgument,
     CommandProvider,
-    Command
+    Command,
+    SubCommand,
 )
 
 from mozbuild.base import MachCommandBase
+import mozpack.path as mozpath
 
 
 @CommandProvider
@@ -72,3 +76,49 @@ class MozbuildFileCommands(MachCommandBase):
             print(line)
 
         return 0
+
+    @Command('file-info', category='build-dev',
+             description='Query for metadata about files.')
+    def file_info(self):
+        pass
+
+    @SubCommand('file-info', 'bugzilla-component',
+                'Show Bugzilla component info for files listed.')
+    @CommandArgument('paths', nargs='+',
+                     help='Paths whose data to query')
+    def file_info_bugzilla(self, paths):
+        components = defaultdict(set)
+        for p, m in self._get_files_info(paths).items():
+            components[m.get('BUG_COMPONENT')].add(p)
+
+        for component, files in sorted(components.items(), key=lambda x: (x is None, x)):
+            print('%s :: %s' % (component.product, component.component) if component else 'UNKNOWN')
+            for f in sorted(files):
+                print('  %s' % f)
+
+    @SubCommand('file-info', 'missing-bugzilla',
+                'Show files missing Bugzilla component info')
+    @CommandArgument('paths', nargs='+',
+                     help='Paths whose data to query')
+    def file_info_missing_bugzilla(self, paths):
+        for p, m in sorted(self._get_files_info(paths).items()):
+            if 'BUG_COMPONENT' not in m:
+                print(p)
+
+    def _get_reader(self):
+        from mozbuild.frontend.reader import BuildReader
+        config = self.config_environment
+        return BuildReader(config)
+
+    def _get_files_info(self, paths):
+        relpaths = []
+        for p in paths:
+            a = mozpath.abspath(p)
+            if not mozpath.basedir(a, [self.topsrcdir]):
+                print('path is not inside topsrcdir: %s' % p)
+                return 1
+
+            relpaths.append(mozpath.relpath(a, self.topsrcdir))
+
+        reader = self._get_reader()
+        return reader.files_info(relpaths)