Add general override functionality. Closes #3001.

mesonbuild/coredata.py

@@ -94,6 +94,27 @@ def validate_value(self, value: T.Any) -> str:
             raise MesonException('Value "%s" for string option is not a string.' % str(value))
         return value
 
+class UserFilePathOption(UserOption[str]):
+    def __init__(self, description: str, value: T.Any, yielding: T.Optional[bool] = None):
+        super().__init__(description, None, yielding)
+        self.path_must_exist = True
+        self.set_value(value)
+
+    def validate_value(self, value: T.Any) -> str:
+        if not isinstance(value, str):
+            raise MesonException('Value "%s" for file path option is not a string.' % str(value))
+        if not value:
+            return value
+         # Store absolute paths, because the original Meson command
+         # might not have been run from the build root.
+        if not os.path.isabs(value):
+            value = os.path.join(os.getcwd(), value)
+        if not self.path_must_exist:
+            return value
+        if not os.path.exists(value):
+            raise MesonException(f'File path "{value}" for does not exist on the file system.')
+        return value
+
 class UserBooleanOption(UserOption[bool]):
     def __init__(self, description: str, value, yielding: T.Optional[bool] = None) -> None:
         super().__init__(description, [True, False], yielding)
@@ -374,6 +395,7 @@ def items(self) -> T.Iterator[T.Tuple['CacheKeyType', T.List['dependencies.Depen
     def clear(self) -> None:
         self.__cache.clear()
 
+
 # Can't bind this near the class method it seems, sadly.
 _V = T.TypeVar('_V')
 
@@ -831,7 +853,7 @@ class MachineFileParser():
     def __init__(self, filenames: T.List[str]) -> None:
         self.parser = CmdLineFileParser()
         self.constants = {'True': True, 'False': False}
-        self.sections = {}
+        self.sections = {}   
 
         self.parser.read(filenames)
 
@@ -1124,24 +1146,25 @@ def add_to_argparse(self, name: str, parser: argparse.ArgumentParser, help_suffi
 ])
 
 BUILTIN_CORE_OPTIONS: 'KeyedOptionDictType' = OrderedDict([
-    (OptionKey('auto_features'),   BuiltinOption(UserFeatureOption, "Override value of all 'auto' features", 'auto')),
-    (OptionKey('backend'),         BuiltinOption(UserComboOption, 'Backend to use', 'ninja', choices=backendlist)),
-    (OptionKey('buildtype'),       BuiltinOption(UserComboOption, 'Build type to use', 'debug',
-                                                 choices=['plain', 'debug', 'debugoptimized', 'release', 'minsize', 'custom'])),
-    (OptionKey('debug'),           BuiltinOption(UserBooleanOption, 'Debug', True)),
-    (OptionKey('default_library'), BuiltinOption(UserComboOption, 'Default library type', 'shared', choices=['shared', 'static', 'both'],
-                                                 yielding=False)),
-    (OptionKey('errorlogs'),       BuiltinOption(UserBooleanOption, "Whether to print the logs from failing tests", True)),
-    (OptionKey('install_umask'),   BuiltinOption(UserUmaskOption, 'Default umask to apply on permissions of installed files', '022')),
-    (OptionKey('layout'),          BuiltinOption(UserComboOption, 'Build directory layout', 'mirror', choices=['mirror', 'flat'])),
-    (OptionKey('optimization'),    BuiltinOption(UserComboOption, 'Optimization level', '0', choices=['0', 'g', '1', '2', '3', 's'])),
-    (OptionKey('stdsplit'),        BuiltinOption(UserBooleanOption, 'Split stdout and stderr in test logs', True)),
-    (OptionKey('strip'),           BuiltinOption(UserBooleanOption, 'Strip targets on install', False)),
-    (OptionKey('unity'),           BuiltinOption(UserComboOption, 'Unity build', 'off', choices=['on', 'off', 'subprojects'])),
-    (OptionKey('unity_size'),      BuiltinOption(UserIntegerOption, 'Unity block size', (2, None, 4))),
-    (OptionKey('warning_level'),   BuiltinOption(UserComboOption, 'Compiler warning level to use', '1', choices=['0', '1', '2', '3'], yielding=False)),
-    (OptionKey('werror'),          BuiltinOption(UserBooleanOption, 'Treat warnings as errors', False, yielding=False)),
-    (OptionKey('wrap_mode'),       BuiltinOption(UserComboOption, 'Wrap mode', 'default', choices=['default', 'nofallback', 'nodownload', 'forcefallback', 'nopromote'])),
+    (OptionKey('auto_features'),      BuiltinOption(UserFeatureOption,  "Override value of all 'auto' features", 'auto')),
+    (OptionKey('backend'),            BuiltinOption(UserComboOption,    'Backend to use', 'ninja', choices=backendlist)),
+    (OptionKey('buildtype'),          BuiltinOption(UserComboOption,    'Build type to use', 'debug',
+                                                    choices=['plain', 'debug', 'debugoptimized', 'release', 'minsize', 'custom'])),
+    (OptionKey('debug'),              BuiltinOption(UserBooleanOption,  'Debug', True)),
+    (OptionKey('default_library'),    BuiltinOption(UserComboOption,    'Default library type', 'shared', choices=['shared', 'static', 'both'],
+                                                    yielding=False)),
+    (OptionKey('errorlogs'),          BuiltinOption(UserBooleanOption,  "Whether to print the logs from failing tests", True)),
+    (OptionKey('install_umask'),      BuiltinOption(UserUmaskOption,    'Default umask to apply on permissions of installed files', '022')),
+    (OptionKey('layout'),             BuiltinOption(UserComboOption,    'Build directory layout', 'mirror', choices=['mirror', 'flat'])),
+    (OptionKey('optimization'),       BuiltinOption(UserComboOption,    'Optimization level', '0', choices=['0', 'g', '1', '2', '3', 's'])),
+    (OptionKey('override_file'),      BuiltinOption(UserFilePathOption, 'Override file path', '')),
+    (OptionKey('stdsplit'),           BuiltinOption(UserBooleanOption,   'Split stdout and stderr in test logs', True)),
+    (OptionKey('strip'),              BuiltinOption(UserBooleanOption,  'Strip targets on install', False)),
+    (OptionKey('unity'),              BuiltinOption(UserComboOption,    'Unity build', 'off', choices=['on', 'off', 'subprojects'])),
+    (OptionKey('unity_size'),         BuiltinOption(UserIntegerOption,  'Unity block size', (2, None, 4))),
+    (OptionKey('warning_level'),      BuiltinOption(UserComboOption,    'Compiler warning level to use', '1', choices=['0', '1', '2', '3'], yielding=False)),
+    (OptionKey('werror'),             BuiltinOption(UserBooleanOption,  'Treat warnings as errors', False, yielding=False)),
+    (OptionKey('wrap_mode'),          BuiltinOption(UserComboOption,    'Wrap mode', 'default', choices=['default', 'nofallback', 'nodownload', 'forcefallback', 'nopromote'])),
     (OptionKey('force_fallback_for'), BuiltinOption(UserArrayOption, 'Force fallback for those subprojects', [])),
 ])
 

mesonbuild/environment.py

@@ -560,6 +560,23 @@ def search_version(text: str) -> str:
 
     return 'unknown version'
 
+class OptionOverrides:
+    def __init__(self):
+        self.subproject_overrides = {} # Overrides option value in all subprojects but not the main project.
+        # FIXME add per-project overrides here
+
+    def add_subprojects_override(self, key, value):
+        self.subproject_overrides[key] = value
+
+    def value_if_overridden(self, key, subproject): # FIXME add target as an argument?
+        if subproject == '':
+            return None
+        if key not in self.subproject_overrides:
+            return None
+        return self.subproject_overrides[key]
+
+
+
 class Environment:
     private_dir = 'meson-private'
     log_dir = 'meson-logs'
@@ -675,6 +692,9 @@ def __init__(self, source_dir: T.Optional[str], build_dir: T.Optional[str], opti
         # Command line options override those from cross/native files
         self.options.update(options.cmd_line_options)
 
+        self.overrides = OptionOverrides()
+        self.init_overrides()
+
         # Take default value from env if not set in cross/native files or command line.
         self._set_default_options_from_env()
         self._set_default_binaries_from_env()
@@ -2185,3 +2205,13 @@ def get_exe_wrapper(self):
         if not self.need_exe_wrapper():
             return EmptyExternalProgram()
         return self.exe_wrapper
+
+    def init_overrides(self) -> None:
+        k = OptionKey('override_file')
+        override_file = self.options[k]
+        if override_file:
+            if not os.path.exists(override_file):
+                raise mesonlib.MesonException(f'Override file {override_file} does not exist.')
+            sections = coredata.MachineFileParser(override_file).sections
+            for k, v in sections.get('override_subprojects', {}).items():
+                self.overrides.add_subprojects_override(k, v)

mesonbuild/interpreter/interpreter.py

@@ -858,6 +858,10 @@ def _do_subproject_cmake(self, subp_name, subdir, subdir_abs, default_options, k
     def get_option_internal(self, optname: str):
         key = OptionKey.from_string(optname).evolve(subproject=self.subproject)
 
+        maybe_v = self.environment.overrides.value_if_overridden(optname, self.subproject)
+        if maybe_v is not None:
+            return maybe_v
+
         if not key.is_project():
             for opts in [self.coredata.options, compilers.base_options]:
                 v = opts.get(key)

mesonbuild/mintro.py

@@ -256,6 +256,8 @@ def add_keys(options: 'cdata.KeyedOptionDictType', section: str) -> None:
                 typestr = 'integer'
             elif isinstance(opt, cdata.UserArrayOption):
                 typestr = 'array'
+            elif isinstance(opt, cdata.UserFilePathOption):
+                typestr = 'filepath'
             else:
                 raise RuntimeError("Unknown option type")
             optdict['type'] = typestr

run_unittests.py

@@ -1720,7 +1720,8 @@ def setUp(self):
         self.common_test_dir = os.path.join(src_root, 'test cases/common')
         self.vala_test_dir = os.path.join(src_root, 'test cases/vala')
         self.framework_test_dir = os.path.join(src_root, 'test cases/frameworks')
-        self.unit_test_dir = os.path.join(src_root, 'test cases/unit')
+        self.unit_test_rel_dir = 'test cases/unit'
+        self.unit_test_dir = os.path.join(src_root, self.unit_test_rel_dir)
         self.rewrite_test_dir = os.path.join(src_root, 'test cases/rewrite')
         self.linuxlike_test_dir = os.path.join(src_root, 'test cases/linuxlike')
         self.objc_test_dir = os.path.join(src_root, 'test cases/objc')
@@ -5705,6 +5706,19 @@ def test_env_flags_to_linker(self) -> None:
                 link_args = env.coredata.get_external_link_args(cc.for_machine, cc.language)
                 self.assertEqual(sorted(link_args), sorted(['-flto']))
 
+    def test_overrides(self):
+        d = '96 overriding'
+        testdir = os.path.join(self.unit_test_dir, d)
+        # Use a relative path to the override file to test that path
+        # preservation works.
+        override_file = os.path.join(self.unit_test_rel_dir, d, 'overrides.txt')
+        self.init(testdir, extra_args=['-Doverride_file='+ override_file])
+        for i in self.introspect('--buildoptions'):
+            if i['name'] == 'override_file':
+                self.assertTrue(os.path.isabs(i['value']))
+                return
+        self.assertTrue(False, 'Unreachable code.')
+
 class FailureTests(BasePlatformTests):
     '''
     Tests that test failure conditions. Build files here should be dynamically

test cases/unit/96 overriding/meson.build

@@ -0,0 +1,4 @@
+project('mainprog', 'c')
+
+assert(get_option('buildtype') == 'debug')
+subproject('somesub')

test cases/unit/96 overriding/overrides.txt

@@ -0,0 +1,2 @@
+[override_subprojects]
+buildtype = 'debugoptimized'

test cases/unit/96 overriding/subprojects/somesub/meson.build

@@ -0,0 +1,3 @@
+project('somesub', 'c')
+
+assert(get_option('buildtype') == 'debugoptimized')