Make it possible to only do unity builds on subprojects.

.travis.yml

@@ -14,7 +14,7 @@ compiler:
 
 env:
   - MESON_ARGS=""
-  - MESON_ARGS="--unity"
+  - MESON_ARGS="--unity=on"
 
 language:
   - cpp

mesonbuild/backend/backends.py

@@ -306,7 +306,7 @@ class Backend:
         # With unity builds, there's just one object that contains all the
         # sources, and we only support extracting all the objects in this mode,
         # so just return that.
-        if self.get_option_for_target('unity', target):
+        if self.is_unity(target):
             comp = get_compiler_for_source(extobj.target.compilers.values(),
                                            extobj.srclist[0])
             # There is a potential conflict here, but it is unlikely that
@@ -607,6 +607,13 @@ class Backend:
                     libs.append(os.path.join(self.get_target_dir(t), f))
         return libs
 
+    def is_unity(self, target):
+        optval = self.get_option_for_target('unity', target)
+        if optval == 'on' or (optval == 'subprojects' and target.subproject != ''):
+            return True
+        return False
+
+
     def get_custom_target_sources(self, target):
         '''
         Custom target sources can be of various object types; strings, File,

mesonbuild/backend/ninjabackend.py

@@ -343,7 +343,7 @@ int dummy;
         outname = self.get_target_filename(target)
         obj_list = []
         use_pch = self.environment.coredata.base_options.get('b_pch', False)
-        is_unity = self.get_option_for_target('unity', target)
+        is_unity = self.is_unity(target)
         if use_pch and target.has_pch():
             pch_objects = self.generate_pch(target, outfile)
         else:

mesonbuild/backend/vs2010backend.py

@@ -614,7 +614,7 @@ class Vs2010Backend(backends.Backend):
         # Prefix to use to access the source tree's subdir from the vcxproj dir
         proj_to_src_dir = os.path.join(proj_to_src_root, target.subdir)
         (sources, headers, objects, languages) = self.split_sources(target.sources)
-        if self.get_option_for_target('unity', target):
+        if self.is_unity(target):
             sources = self.generate_unity_files(target, sources)
         compiler = self._get_cl_compiler(target)
         buildtype_args = compiler.get_buildtype_args(self.buildtype)

mesonbuild/build.py

@@ -307,7 +307,8 @@ class BuildTarget(Target):
         super().__init__(name, subdir, True)
         self.subproject = subproject # Can not be calculated from subdir as subproject dirname can be changed per project.
         self.is_cross = is_cross
-        self.is_unity = environment.coredata.get_builtin_option('unity')
+        unity_opt = environment.coredata.get_builtin_option('unity')
+        self.is_unity = unity_opt == 'on' or (unity_opt == 'subprojects' and subproject != '')
         self.environment = environment
         self.sources = []
         self.compilers = OrderedDict()

mesonbuild/coredata.py

@@ -295,7 +295,7 @@ def get_builtin_option_default(optname):
 builtin_options = {
     'buildtype':  [UserComboOption, 'Build type to use.', ['plain', 'debug', 'debugoptimized', 'release', 'minsize'], 'debug'],
     'strip':      [UserBooleanOption, 'Strip targets on install.', False],
-    'unity':      [UserBooleanOption, 'Unity build.', False],
+    'unity':      [UserComboOption, 'Unity build.', ['on', 'off', 'subprojects'], 'off'],
     'prefix':     [UserStringOption, 'Installation prefix.', default_prefix()],
     'libdir':     [UserStringOption, 'Library directory.', default_libdir()],
     'libexecdir': [UserStringOption, 'Library executable directory.', default_libexecdir()],

mesonbuild/interpreter.py

@@ -1188,7 +1188,10 @@ class MesonMain(InterpreterObject):
         raise InterpreterException('Tried to access compiler for unspecified language "%s".' % cname)
 
     def is_unity_method(self, args, kwargs):
-        return self.build.environment.coredata.get_builtin_option('unity')
+        optval = self.interpreter.environment.coredata.get_builtin_option('unity')
+        if optval == 'on' or (optval == 'subprojects' and self.interpreter.subproject != ''):
+            return True
+        return False
 
     def is_subproject_method(self, args, kwargs):
         return self.interpreter.is_subproject()

mesonbuild/mesonmain.py

@@ -54,7 +54,7 @@ add_builtin_argument('sharedstatedir')
 add_builtin_argument('backend')
 add_builtin_argument('buildtype')
 add_builtin_argument('strip', action='store_true')
-add_builtin_argument('unity', action='store_true')
+add_builtin_argument('unity')
 add_builtin_argument('werror', action='store_true')
 add_builtin_argument('layout')
 add_builtin_argument('default-library')

run_unittests.py

@@ -390,8 +390,11 @@ class BasePlatformTests(unittest.TestCase):
         return output
 
     def init(self, srcdir, extra_args=None, default_args=True):
+        self.assertTrue(os.path.exists(srcdir))
         if extra_args is None:
             extra_args = []
+        if not isinstance(extra_args, list):
+            extra_args = [extra_args]
         args = [srcdir, self.builddir]
         if default_args:
             args += ['--prefix', self.prefix,
@@ -1374,6 +1377,14 @@ class LinuxlikeTests(BasePlatformTests):
         cpp = env.detect_cpp_compiler(False)
         self._test_stds_impl(testdir, cpp, 'cpp')
 
+    def test_unity_subproj(self):
+        testdir = os.path.join(self.common_test_dir, '49 subproject')
+        self.init(testdir, extra_args='--unity=subprojects')
+        self.assertTrue(os.path.exists(os.path.join(self.builddir, 'subprojects/sublib/simpletest@exe/simpletest-unity.c')))
+        self.assertTrue(os.path.exists(os.path.join(self.builddir, 'subprojects/sublib/sublib@sha/sublib-unity.c')))
+        self.assertFalse(os.path.exists(os.path.join(self.builddir, 'user@exe/user-unity.c')))
+        self.build()
+
     def test_installed_modes(self):
         '''
         Test that files installed by these tests have the correct permissions.

test cases/common/139 override options/meson.build

@@ -1,8 +1,6 @@
 project('option override', 'c',
-  default_options : 'unity=true')
+  default_options : 'unity=on')
 
 executable('mustunity', 'one.c', 'two.c')
 executable('notunity', 'three.c', 'four.c',
-  override_options : ['unity=false'])
-
-
+  override_options : ['unity=off'])