IncludeDirs store build-only-subproject

The builddir will not mirror the subdir in this case, and we need to
track that.

mesonbuild/build.py

@@ -433,6 +433,9 @@ class IncludeDirs(HoldableObject):
     # actually exist.
     extra_build_dirs: T.List[str] = field(default_factory=list)
 
+    # We need to know this for stringifying correctly
+    is_build_only_subproject: bool = False
+
     def __repr__(self) -> str:
         r = '<{} {}/{}>'
         return r.format(self.__class__.__name__, self.curdir, self.incdirs)
@@ -1598,7 +1601,7 @@ def add_include_dirs(self, args: T.Sequence['IncludeDirs'], set_is_system: T.Opt
             set_is_system = 'preserve'
         if set_is_system != 'preserve':
             is_system = set_is_system == 'system'
-            ids = [IncludeDirs(x.get_curdir(), x.get_incdirs(), is_system, x.get_extra_build_dirs()) for x in ids]
+            ids = [IncludeDirs(x.get_curdir(), x.get_incdirs(), is_system, x.get_extra_build_dirs(), x.is_build_only_subproject) for x in ids]
         self.include_dirs += ids
 
     def add_compiler_args(self, language: str, args: T.List['FileOrString']) -> None:

mesonbuild/interpreter/interpreter.py

@@ -2890,7 +2890,8 @@ def build_incdir_object(self, incdir_strings: T.List[str], is_system: bool = Fal
             absdir_build = os.path.join(absbase_build, a)
             if not os.path.isdir(absdir_src) and not os.path.isdir(absdir_build):
                 raise InvalidArguments(f'Include dir {a} does not exist.')
-        i = build.IncludeDirs(self.subdir, incdir_strings, is_system)
+        i = build.IncludeDirs(
+            self.subdir, incdir_strings, is_system, is_build_only_subproject=self.build.is_build_only)
         return i
 
     @typed_pos_args('add_test_setup', str)

mesonbuild/interpreter/interpreterobjects.py

@@ -875,7 +875,8 @@ def found_method(self, args: T.List[TYPE_var], kwargs: TYPE_kwargs) -> bool:
     @noPosargs
     @noKwargs
     def private_dir_include_method(self, args: T.List[TYPE_var], kwargs: TYPE_kwargs) -> build.IncludeDirs:
-        return build.IncludeDirs('', [], False, [self.interpreter.backend.get_target_private_dir(self._target_object)])
+        return build.IncludeDirs('', [], False, [self.interpreter.backend.get_target_private_dir(self._target_object)],
+                                 self.interpreter.build.is_build_only)
 
     @noPosargs
     @noKwargs

mesonbuild/modules/gnome.py

@@ -2205,7 +2205,8 @@ def generate_vapi(self, state: 'ModuleState', args: T.Tuple[str], kwargs: 'Gener
         # - link with the correct library
         # - include the vapi and dependent vapi files in sources
         # - add relevant directories to include dirs
-        incs = [build.IncludeDirs(state.subdir, ['.'] + vapi_includes, False)]
+        incs = [build.IncludeDirs(state.subdir, ['.'] + vapi_includes, False,
+                is_build_only_subproject=state.is_build_only_subproject)]
         sources = [vapi_target] + vapi_depends
         rv = InternalDependency(None, incs, [], [], link_with, [], sources, [], [], {}, [], [], [])
         created_values.append(rv)

mesonbuild/modules/windows.py

@@ -129,7 +129,8 @@ def compile_resources(self, state: 'ModuleState',
         for d in wrc_depends:
             if isinstance(d, build.CustomTarget):
                 extra_args += state.get_include_args([
-                    build.IncludeDirs('', [], False, [os.path.join('@BUILD_ROOT@', self.interpreter.backend.get_target_dir(d))])
+                    build.IncludeDirs('', [], False, [os.path.join('@BUILD_ROOT@', self.interpreter.backend.get_target_dir(d))],
+                                      state.is_build_only_subproject)
                 ])
         extra_args += state.get_include_args(kwargs['include_directories'])