Bug 1345109 - Delete 'JS_STANDALONE' from EmptyConfig when generating test metadata, r=mshal

EmptyConfig objects set JS_STANDALONE=1 by default. However, test tasks that need to run without an objdir
need to be behind an "if not CONFIG['JS_STANDALONE']" condition to avoid causing bustage to sm-pkg task (js
packaging). This patch explicitly deletes that default value, only when generating the TestManifestBackend.

Ideally, the js/src packaging should have their own moz.build instead of re-using the root moz.build. But this
is an easier fix in the short term to get the marionette-harness tests working again.

MozReview-Commit-ID: 26lHLY6WlZK

--HG--
extra : rebase_source : 9c2ffdd938f2f2d6ead7d2aead610a7028e18d97

build/gen_test_backend.py

@@ -16,7 +16,14 @@ def gen_test_backend():
         config = build_obj.config_environment
     except BuildEnvironmentNotFoundException:
         print("No build detected, test metadata may be incomplete.")
-        config = EmptyConfig(build_obj.topsrcdir)
+
+        # If 'JS_STANDALONE' is set, tests that don't require an objdir won't
+        # be picked up due to bug 1345209.
+        substs = EmptyConfig.default_substs
+        if 'JS_STANDALONE' in substs:
+            del substs['JS_STANDALONE']
+
+        config = EmptyConfig(build_obj.topsrcdir, substs)
         config.topobjdir = build_obj.topobjdir
 
     reader = BuildReader(config)

moz.build

@@ -26,6 +26,11 @@ DIRS += [
 ]
 
 if not CONFIG['JS_STANDALONE']:
+    # These python manifests are included here so they get picked up without an objdir
+    PYTHON_UNITTEST_MANIFESTS += [
+        'testing/marionette/harness/marionette_harness/tests/harness_unit/python.ini',
+    ]
+
     CONFIGURE_SUBST_FILES += [
         'tools/update-packaging/Makefile',
     ]
@@ -85,12 +90,6 @@ if not CONFIG['JS_STANDALONE'] and CONFIG['MOZ_BUILD_APP']:
     # Bring in the configuration for the configured application.
     include('/' + CONFIG['MOZ_BUILD_APP'] + '/app.mozbuild')
 
-if not CONFIG['JS_STANDALONE']:
-    # These python manifests are included here so they get picked up without an objdir
-    PYTHON_UNITTEST_MANIFESTS += [
-        'testing/marionette/harness/marionette_harness/tests/harness_unit/python.ini',
-    ]
-
 CONFIGURE_SUBST_FILES += ['.cargo/config']
 
 include('build/templates.mozbuild')

python/mozbuild/mozbuild/frontend/reader.py

@@ -113,21 +113,23 @@ class EmptyConfig(object):
         def get(self, key, default=None):
             return self[key]
 
-    def __init__(self, topsrcdir):
+    default_substs = {
+        # These 2 variables are used semi-frequently and it isn't worth
+        # changing all the instances.
+        b'MOZ_APP_NAME': b'empty',
+        b'MOZ_CHILD_PROCESS_NAME': b'empty',
+        # Set manipulations are performed within the moz.build files. But
+        # set() is not an exposed symbol, so we can't create an empty set.
+        b'NECKO_PROTOCOLS': set(),
+        # Needed to prevent js/src's config.status from loading.
+        b'JS_STANDALONE': b'1',
+    }
+
+    def __init__(self, topsrcdir, substs=None):
         self.topsrcdir = topsrcdir
         self.topobjdir = ''
 
-        self.substs = self.PopulateOnGetDict(EmptyValue, {
+        self.substs = self.PopulateOnGetDict(EmptyValue, substs or self.default_substs)
-            # These 2 variables are used semi-frequently and it isn't worth
-            # changing all the instances.
-            b'MOZ_APP_NAME': b'empty',
-            b'MOZ_CHILD_PROCESS_NAME': b'empty',
-            # Set manipulations are performed within the moz.build files. But
-            # set() is not an exposed symbol, so we can't create an empty set.
-            b'NECKO_PROTOCOLS': set(),
-            # Needed to prevent js/src's config.status from loading.
-            b'JS_STANDALONE': b'1',
-        })
         udict = {}
         for k, v in self.substs.items():
             if isinstance(v, str):