Use typed_kwargs for build_target(install_dir:)

docs/markdown/Python-module.md

@@ -130,6 +130,9 @@ the addition of the following:
 
 Additionally, the following diverge from [[shared_module]]'s default behavior:
 
+- `install_dir` may only be a string, boolean, or unset, but an `array` is not
+  allowed.
+
 - `gnu_symbol_visibility`: if unset, it will default to `'hidden'` on versions
   of Python that support this (the python headers define `PyMODINIT_FUNC` has
   default visibility).

docs/yaml/functions/_build_target_base.yaml

@@ -169,13 +169,17 @@ kwargs:
     description: When set to true, this executable should be installed.
 
   install_dir:
-    type: str
+    type: array[str | bool]
     description: |
       override install directory for this file. If the value is a relative path,
       it will be considered relative the `prefix` option.
       For example, if you want to install plugins into a subdir, you'd use
       something like this: `install_dir : get_option('libdir') / 'projectname-1.0'`.
 
+      This can be set to an array of values to control the the installation path
+      of build targets with multiple outputs. Currently, that means Vala. Setting
+      them to `true` means "use the default", and `false` means, don't install.
+
   install_mode:
     type: array[str | int]
     since: 0.47.0

mesonbuild/backend/backends.py

@@ -1690,10 +1690,10 @@ def generate_target_install(self, d: InstallData) -> None:
             # Sanity-check the outputs and install_dirs
             num_outdirs, num_out = len(outdirs), len(t.get_outputs())
             if num_outdirs not in {1, num_out}:
-                m = 'Target {!r} has {} outputs: {!r}, but only {} "install_dir"s were found.\n' \
+                m = 'Target {!r} has {} outputs: {!r}, but {} "install_dir"s were found: {!r}.\n' \
                     "Pass 'false' for outputs that should not be installed and 'true' for\n" \
                     'using the default installation directory for an output.'
-                raise MesonException(m.format(t.name, num_out, t.get_outputs(), num_outdirs))
+                raise MesonException(m.format(t.name, num_out, t.get_outputs(), num_outdirs, outdirs))
             assert len(t.install_tag) == num_out
             install_mode = t.get_custom_install_mode()
             # because mypy gets confused type narrowing in lists

mesonbuild/build.py

@@ -22,7 +22,7 @@
 from .mesonlib import (
     HoldableObject, SecondLevelHolder,
     File, MesonException, MachineChoice, PerMachine, OrderedSet, listify,
-    extract_as_list, typeslistify, classify_unity_sources,
+    extract_as_list, classify_unity_sources,
     get_filenames_templates_dict, substitute_values, has_path_sep,
     is_parent_path, relpath, PerMachineDefaultable,
     MesonBugException, EnvironmentVariables, pickle_load, lazy_property,
@@ -1292,8 +1292,7 @@ def process_kwargs(self, kwargs: BuildTargetKeywordArguments) -> None:
         self.add_deps(deplist)
         # If an item in this list is False, the output corresponding to
         # the list index of that item will not be installed
-        self.install_dir = typeslistify(kwargs.get('install_dir', []),
-                                        (str, bool))
+        self.install_dir = kwargs.get('install_dir', [])
         self.install_mode = kwargs.get('install_mode', None)
         self.install_tag: T.List[T.Optional[str]] = kwargs.get('install_tag') or [None]
         self.extra_files = kwargs.get('extra_files', [])

mesonbuild/interpreter/kwargs.py

@@ -366,6 +366,7 @@ class _BuildTarget(_BaseBuildTarget):
     d_import_dirs: T.List[T.Union[str, build.IncludeDirs]]
     d_module_versions: T.List[T.Union[str, int]]
     d_unittest: bool
+    install_dir: T.List[T.Union[str, bool]]
     rust_crate_type: T.Optional[Literal['bin', 'lib', 'rlib', 'dylib', 'cdylib', 'staticlib', 'proc-macro']]
     rust_dependency_map: T.Dict[str, str]
     swift_interoperability_mode: Literal['c', 'cpp']

mesonbuild/interpreter/type_checking.py

@@ -615,6 +615,12 @@ def _extra_files_validator(args: T.List[T.Union[File, str]]) -> T.Optional[str]:
     ),
     INSTALL_MODE_KW,
     INSTALL_TAG_KW,
+    KwargInfo(
+        'install_dir',
+        ContainerTypeInfo(list, (str, bool)),
+        default=[],
+        listify=True,
+    ),
     KwargInfo('implicit_include_directories', bool, default=True, since='0.42.0'),
     NATIVE_KW,
     KwargInfo('resources', ContainerTypeInfo(list, str), default=[], listify=True),

mesonbuild/modules/python.py

@@ -51,6 +51,8 @@ class FindInstallationKw(ExtractRequired):
 
     class ExtensionModuleKw(SharedModuleKw):
 
+        # Yes, these are different between SharedModule and ExtensionModule
+        install_dir: T.Union[str, bool, None]  # type: ignore[misc]
         subdir: NotRequired[T.Optional[str]]
 
     MaybePythonProg = T.Union[NonExistingExternalProgram, 'PythonExternalProgram']
@@ -60,7 +62,8 @@ class ExtensionModuleKw(SharedModuleKw):
 mod_kwargs.update(known_shmod_kwargs)
 mod_kwargs -= {'name_prefix', 'name_suffix'}
 
-_MOD_KWARGS = [k for k in SHARED_MOD_KWS if k.name not in {'name_prefix', 'name_suffix'}]
+_MOD_KWARGS = [k for k in SHARED_MOD_KWS if
+               k.name not in {'name_prefix', 'name_suffix', 'install_dir'}]
 
 
 class PythonExternalProgram(BasicPythonExternalProgram):
@@ -139,19 +142,28 @@ def __init__(self, python: 'PythonExternalProgram', interpreter: 'Interpreter'):
 
     @permittedKwargs(mod_kwargs)
     @typed_pos_args('python.extension_module', str, varargs=(str, mesonlib.File, CustomTarget, CustomTargetIndex, GeneratedList, StructuredSources, ExtractedObjects, BuildTarget))
-    @typed_kwargs('python.extension_module', *_MOD_KWARGS, _DEFAULTABLE_SUBDIR_KW, _LIMITED_API_KW, allow_unknown=True)
+    @typed_kwargs(
+        'python.extension_module',
+        *_MOD_KWARGS,
+        _DEFAULTABLE_SUBDIR_KW,
+        _LIMITED_API_KW,
+        KwargInfo('install_dir', (str, bool, NoneType)),
+        allow_unknown=True
+    )
     @InterpreterObject.method('extension_module')
     def extension_module_method(self, args: T.Tuple[str, T.List[BuildTargetSource]], kwargs: ExtensionModuleKw) -> 'SharedModule':
-        if 'install_dir' in kwargs:
+        if kwargs['install_dir'] is not None:
             if kwargs['subdir'] is not None:
                 raise InvalidArguments('"subdir" and "install_dir" are mutually exclusive')
+            # the build_target() method now expects this to be correct.
+            kwargs['install_dir'] = [kwargs['install_dir']]
         else:
             # We want to remove 'subdir', but it may be None and we want to replace it with ''
             # It must be done this way since we don't allow both `install_dir`
             # and `subdir` to be set at the same time
             subdir = kwargs.pop('subdir') or ''
 
-            kwargs['install_dir'] = self._get_install_dir_impl(False, subdir)
+            kwargs['install_dir'] = [self._get_install_dir_impl(False, subdir)]
 
         target_suffix = self.suffix
 

test cases/failing/40 custom target outputs not matching install_dirs/test.json

@@ -27,7 +27,8 @@
   ],
   "stdout": [
     {
-      "line": "ERROR: Target 'too-few-install-dirs' has 3 outputs: ['toofew.h', 'toofew.c', 'toofew.sh'], but only 2 \"install_dir\"s were found."
+      "line": "ERROR: Target 'too-few-install-dirs' has 3 outputs: \\['toofew.h', 'toofew.c', 'toofew.sh'\\], but 2 \"install_dir\"s were found: \\['([a-zA-Z]:)?/usr/include', False\\]\\.",
+      "match": "re"
     }
   ]
 }