Changes ninja generator to only output empty names if not already output

This builds on https://codereview.chromium.org/543743003/ .

BUG=410410
TEST=covered by test now
R=thakis@chromium.org

Review URL: https://codereview.chromium.org/547393003

git-svn-id: http://gyp.googlecode.com/svn/trunk@1974 78cadc50-ecff-11dd-a971-7dbc132099af

4 files changed, 72 insertions, 5 deletions

diff --git a/pylib/gyp/generator/ninja.py b/pylib/gyp/generator/ninja.py
index f5e1be96..4484f93a 100644
--- a/pylib/gyp/generator/ninja.py
+++ b/pylib/gyp/generator/ninja.py
@@ -2152,7 +2152,12 @@ def GenerateOutputForConfig(target_list, target_dicts, data, params,
 
   # short name of targets that were skipped because they didn't contain anything
   # interesting.
-  empty_target_names = []
+  # NOTE: there may be overlap between this an non_empty_target_names.
+  empty_target_names = set()
+
+  # Set of non-empty short target names.
+  # NOTE: there may be overlap between this an empty_target_names.
+  non_empty_target_names = set()
 
   for qualified_target in target_list:
     # qualified_target is like: third_party/icu/icu.gyp:icui18n#target
@@ -2197,8 +2202,9 @@ def GenerateOutputForConfig(target_list, target_dicts, data, params,
       target_outputs[qualified_target] = target
       if qualified_target in all_targets:
         all_outputs.add(target.FinalOutput())
+      non_empty_target_names.add(name)
     else:
-      empty_target_names.append(name)
+      empty_target_names.add(name)
 
   if target_short_names:
     # Write a short name to build this target.  This benefits both the
@@ -2210,10 +2216,11 @@ def GenerateOutputForConfig(target_list, target_dicts, data, params,
       master_ninja.build(short_name, 'phony', [x.FinalOutput() for x in
                                                target_short_names[short_name]])
 
+  # Write phony targets for any empty targets that weren't written yet. As
+  # short names are  not necessarily unique only do this for short names that
+  # haven't already been output for another target.
+  empty_target_names = empty_target_names - non_empty_target_names
   if empty_target_names:
-    # Write out any targets that were skipped because they didn't contain
-    # anything interesting. This way the targets can still be built without
-    # causing build errors.
     master_ninja.newline()
     master_ninja.comment('Empty targets (output for completeness).')
     for name in sorted(empty_target_names):
diff --git a/test/ninja/empty-and-non-empty-duplicate-name/gyptest-empty-and-non-empty-duplicate-name.py b/test/ninja/empty-and-non-empty-duplicate-name/gyptest-empty-and-non-empty-duplicate-name.py
new file mode 100644
index 00000000..1279ead3
--- /dev/null
+++ b/test/ninja/empty-and-non-empty-duplicate-name/gyptest-empty-and-non-empty-duplicate-name.py
@@ -0,0 +1,22 @@
+#!/usr/bin/env python
+
+# Copyright (c) 2014 Google Inc. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""
+Verifies a phony target isn't output if a target exists with the same name that
+was output.
+"""
+
+import TestGyp
+
+test = TestGyp.TestGyp(formats=['ninja'])
+
+test.run_gyp('test.gyp')
+
+# Check for both \r and \n to cover both windows and linux.
+test.must_not_contain('out/Default/build.ninja', 'build empty_target: phony\r')
+test.must_not_contain('out/Default/build.ninja', 'build empty_target: phony\n')
+
+test.pass_test()
diff --git a/test/ninja/empty-and-non-empty-duplicate-name/subdir/included.gyp b/test/ninja/empty-and-non-empty-duplicate-name/subdir/included.gyp
new file mode 100644
index 00000000..1b9fc42f
--- /dev/null
+++ b/test/ninja/empty-and-non-empty-duplicate-name/subdir/included.gyp
@@ -0,0 +1,19 @@
+# Copyright (c) 2014 Google Inc. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'targets': [
+    {
+      'target_name': 'empty_target',
+      'type': 'executable',
+      'sources': [
+        'test.cc',
+      ],
+    },
+    {
+      'target_name': 'included_empty_target',
+      'type': 'none',
+    },
+  ],
+}
diff --git a/test/ninja/empty-and-non-empty-duplicate-name/test.gyp b/test/ninja/empty-and-non-empty-duplicate-name/test.gyp
new file mode 100644
index 00000000..9aa6287c
--- /dev/null
+++ b/test/ninja/empty-and-non-empty-duplicate-name/test.gyp
@@ -0,0 +1,19 @@
+# Copyright (c) 2014 Google Inc. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'targets': [
+    {
+      'target_name': 'All',
+      'type': 'none',
+      'dependencies': [
+        'subdir/included.gyp:included_empty_target'
+      ]
+    },
+    {
+      'target_name': 'empty_target',
+      'type': 'none',
+    },
+  ],
+}