Bug 836208 - Part 2: Make |mach build some/Makefile| start one level up. r=glandium

python/mozbuild/mozbuild/test/test_util.py

@@ -119,6 +119,8 @@ class TestResolveTargetToMake(unittest.TestCase):
 
     def test_top_level(self):
         self.assertResolve('package', (None, 'package'))
+        # Makefile handling shouldn't affect top-level targets.
+        self.assertResolve('Makefile', (None, 'Makefile'))
 
     def test_regular_file(self):
         self.assertResolve('test-dir/with/file', ('test-dir/with', 'file'))
@@ -129,6 +131,14 @@ class TestResolveTargetToMake(unittest.TestCase):
         self.assertResolve('test-dir/without/with/file', ('test-dir/without/with', 'file'))
         self.assertResolve('test-dir/without/with/without/file', ('test-dir/without/with', 'without/file'))
 
+    def test_Makefile(self):
+        self.assertResolve('test-dir/with/Makefile', ('test-dir', 'with/Makefile'))
+        self.assertResolve('test-dir/with/without/Makefile', ('test-dir/with', 'without/Makefile'))
+        self.assertResolve('test-dir/with/without/with/Makefile', ('test-dir/with', 'without/with/Makefile'))
+
+        self.assertResolve('test-dir/without/Makefile', ('test-dir', 'without/Makefile'))
+        self.assertResolve('test-dir/without/with/Makefile', ('test-dir', 'without/with/Makefile'))
+        self.assertResolve('test-dir/without/with/without/Makefile', ('test-dir/without/with', 'without/Makefile'))
 
 if __name__ == '__main__':
     main()

python/mozbuild/mozbuild/util.py

@@ -162,8 +162,13 @@ def resolve_target_to_make(topobjdir, target):
     A directory resolves to the nearest directory at or above
     containing a Makefile, and target `None`.
 
-    A file resolves to the nearest directory at or above the file
-    containing a Makefile, and an appropriate target.
+    A regular (non-Makefile) file resolves to the nearest directory at
+    or above the file containing a Makefile, and an appropriate
+    target.
+
+    A Makefile resolves to the nearest parent strictly above the
+    Makefile containing a different Makefile, and an appropriate
+    target.
     '''
     if os.path.isabs(target):
         print('Absolute paths for make targets are not allowed.')
@@ -200,7 +205,9 @@ def resolve_target_to_make(topobjdir, target):
     while True:
         make_path = os.path.join(topobjdir, reldir, 'Makefile')
 
-        if os.path.exists(make_path):
+        # We append to target every iteration, so the check below
+        # happens exactly once.
+        if target != 'Makefile' and os.path.exists(make_path):
             return (reldir, target)
 
         target = os.path.join(os.path.basename(reldir), target)