Add build target keyword parameter 'build_subdir' [v8]

Place the build products in a directory of the specified name
somewhere within the build directory. This allows use of the target
that includes a specific directory name:

        #include <subdir/configure.h>

This also allows creating targets with the same basename by using
different subdirectory names.

v2:
    Move build_subdir to Target class.
    Error if path separator in build_dir

v3:
    Rename to 'build_subdir' to make it clear that the name is
    appended to a meson-specific build directory, and does not
    provide the user with a way to define the overall meson build
    hierarchy.

    Allow build_subdir to include path separators.

    Support 'build_subdir' for configure_file.

    build_subdir must not exist in the source directory and
    must not contain '..'

    Add documentation and tests

v4:
    Rebase and prepare for version 1.9.1

    Add failing test case when build_subdir is present in the
    project.

    Add release note snippet

v5:
    Clarify wording on restrictions on the value of build_subdir. Use
    the same wording in each place this restriction is described.

v6:
    Move path validation to shared function, validate_build_subdir,
    instead of duplicating the tests in two places.

v7:
    Update version numbers to 1.10.0
    Add TypedDict updates.
    Remove spurious build_subdir instance variable

v8:
    Oops, missed one version number update.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 8 insertions, 5 deletions

diff --git a/mesonbuild/backend/backends.py b/mesonbuild/backend/backends.py
index db7b5785c..545b41756 100644
--- a/mesonbuild/backend/backends.py
+++ b/mesonbuild/backend/backends.py
@@ -336,9 +336,9 @@ class Backend:
 
     def get_build_dir_include_args(self, target: build.BuildTarget, compiler: 'Compiler', *, absolute_path: bool = False) -> T.List[str]:
         if absolute_path:
-            curdir = os.path.join(self.build_dir, target.get_subdir())
+            curdir = os.path.join(self.build_dir, target.get_builddir())
         else:
-            curdir = target.get_subdir()
+            curdir = target.get_builddir()
             if curdir == '':
                 curdir = '.'
         return compiler.get_include_args(curdir, False)
@@ -373,9 +373,12 @@ class Backend:
             # this produces no output, only a dummy top-level name
             dirname = ''
         elif self.environment.coredata.optstore.get_value_for(OptionKey('layout')) == 'mirror':
-            dirname = target.get_subdir()
+            dirname = target.get_builddir()
         else:
             dirname = 'meson-out'
+            build_subdir = target.get_build_subdir()
+            if build_subdir:
+                dirname = os.path.join(dirname, build_subdir)
         return dirname
 
     def get_target_dir_relative_to(self,
@@ -488,7 +491,7 @@ class Backend:
         for obj in objects:
             if isinstance(obj, str):
                 o = os.path.join(proj_dir_to_build_root,
-                                 self.build_to_src, target.get_subdir(), obj)
+                                 self.build_to_src, target.get_builddir(), obj)
                 obj_list.append(o)
             elif isinstance(obj, mesonlib.File):
                 if obj.is_built:
@@ -1229,7 +1232,7 @@ class Backend:
                                 ld_lib_path_libs.add(l)
 
                 env_build_dir = self.environment.get_build_dir()
-                ld_lib_path: T.Set[str] = set(os.path.join(env_build_dir, l.get_subdir()) for l in ld_lib_path_libs)
+                ld_lib_path: T.Set[str] = set(os.path.join(env_build_dir, l.get_builddir()) for l in ld_lib_path_libs)
 
                 if ld_lib_path:
                     t_env.prepend('LD_LIBRARY_PATH', list(ld_lib_path), ':')