alias_target with both_libs builds both

docs/markdown/snippets/alias_target_of_both_libraries.md

@@ -0,0 +1,5 @@
+## `alias_target` of `both_libraries`
+
+Previously, when passing a [[@both_libs]] object to [[alias_target]], the alias
+would only point to the shared library. It now points to both the static and the
+shared library.

docs/markdown/snippets/dep_as_shared_as_static.md

@@ -0,0 +1,8 @@
+## New `as_static` and `as_shared` methods on internal dependencies
+
+[[@dep]] object returned by [[declare_dependency]] now has `.as_static()` and
+`.as_shared()` methods, to convert to a dependency that prefers the `static`
+or the `shared` version of the linked [[@both_libs]] target.
+
+When the same dependency is used without those methods, the
+`default_both_libraries` option determines which version is used.

docs/yaml/functions/alias_target.yaml

@@ -9,6 +9,9 @@ description: |
   are built. Dependencies can be any build target. Since 0.60.0, this includes
   [[@run_tgt]].
 
+  *Since 1.6.0* passing a [[@both_libs]] object builds both shared and
+  static libraries.
+
 posargs:
   target_name:
     type: str

docs/yaml/objects/dep.yaml

@@ -221,3 +221,28 @@ methods:
       pkgconfig_define:
         type: list[str]
         description: See [[dep.get_pkgconfig_variable]]
+
+  - name: as_static
+    returns: dep
+    since: 1.6.0
+    description: |
+      Only for dependencies created with [[declare_dependency]],
+      returns a copy of the dependency object that prefer the `static` version
+      of [[both_libraries]].
+    kwargs:
+      recursive:
+        type: bool
+        description: If true, this is recursively applied to dependencies
+
+  - name: as_shared
+    returns: dep
+    since: 1.6.0
+    description: |
+      Only for dependencies created with [[declare_dependency]],
+      returns a copy of the dependency object that prefer the `shared` version
+      of [[both_libraries]].
+    kwargs:
+      recursive:
+        type: bool
+        description: If true, this is recursively applied to dependencies
+  

mesonbuild/build.py

@@ -1746,6 +1746,10 @@ class BuildTarget(Target):
         lib_list = listify(kwargs.get(key, [])) + self_libs
         return [_resolve_both_libs(t) for t in lib_list]
 
+    def get(self, lib_type: T.Literal['static', 'shared', 'auto']) -> LibTypes:
+        """Base case used by BothLibraries"""
+        return self
+
 class FileInTargetPrivateDir:
     """Represents a file with the path '/path/to/build/target_private_dir/fname'.
        target_private_dir is the return value of get_target_private_dir which is e.g. 'subdir/target.p'.
@@ -2501,7 +2505,7 @@ class BothLibraries(SecondLevelHolder):
     def __repr__(self) -> str:
         return f'<BothLibraries: static={repr(self.static)}; shared={repr(self.shared)}>'
 
-    def get(self, lib_type: T.Literal['static', 'shared', 'auto']) -> T.Union[StaticLibrary, SharedLibrary]:
+    def get(self, lib_type: T.Literal['static', 'shared', 'auto']) -> LibTypes:
         if lib_type == 'static':
             return self.static
         if lib_type == 'shared':
@@ -2575,6 +2579,10 @@ class CustomTargetBase:
     def get_internal_static_libraries_recurse(self, result: OrderedSet[BuildTargetTypes]) -> None:
         pass
 
+    def get(self, lib_type: T.Literal['static', 'shared', 'auto']) -> LibTypes:
+        """Base case used by BothLibraries"""
+        return self
+
 class CustomTarget(Target, CustomTargetBase, CommandBase):
 
     typename = 'custom'
@@ -2896,14 +2904,23 @@ class AliasTarget(RunTarget):
 
     typename = 'alias'
 
-    def __init__(self, name: str, dependencies: T.Sequence['Target'],
+    def __init__(self, name: str, dependencies: T.Sequence[T.Union[Target, BothLibraries]],
                  subdir: str, subproject: str, environment: environment.Environment):
-        super().__init__(name, [], dependencies, subdir, subproject, environment)
+        super().__init__(name, [], list(self._deps_generator(dependencies)), subdir, subproject, environment)
 
     def __repr__(self):
         repr_str = "<{0} {1}>"
         return repr_str.format(self.__class__.__name__, self.get_id())
 
+    @staticmethod
+    def _deps_generator(dependencies: T.Sequence[T.Union[Target, BothLibraries]]) -> T.Iterator[Target]:
+        for dep in dependencies:
+            if isinstance(dep, BothLibraries):
+                yield dep.shared
+                yield dep.static
+            else:
+                yield dep
+
 class Jar(BuildTarget):
     known_kwargs = known_jar_kwargs
 

mesonbuild/dependencies/base.py

@@ -248,6 +248,14 @@ class Dependency(HoldableObject):
         new_dep.include_type = self._process_include_type_kw({'include_type': include_type})
         return new_dep
 
+    def get_as_static(self, recursive: bool) -> Dependency:
+        """Used as base case for internal_dependency"""
+        return self
+
+    def get_as_shared(self, recursive: bool) -> Dependency:
+        """Used as base case for internal_dependency"""
+        return self
+
 class InternalDependency(Dependency):
     def __init__(self, version: str, incdirs: T.List['IncludeDirs'], compile_args: T.List[str],
                  link_args: T.List[str],
@@ -345,6 +353,20 @@ class InternalDependency(Dependency):
         new_dep.libraries = []
         return new_dep
 
+    def get_as_static(self, recursive: bool) -> Dependency:
+        new_dep = copy.copy(self)
+        new_dep.libraries = [lib.get('static') for lib in self.libraries]
+        if recursive:
+            new_dep.ext_deps = [dep.get_as_static(True) for dep in self.ext_deps]
+        return new_dep
+
+    def get_as_shared(self, recursive: bool) -> Dependency:
+        new_dep = copy.copy(self)
+        new_dep.libraries = [lib.get('shared') for lib in self.libraries]
+        if recursive:
+            new_dep.ext_deps = [dep.get_as_shared(True) for dep in self.ext_deps]
+        return new_dep
+
 class HasNativeKwarg:
     def __init__(self, kwargs: T.Dict[str, T.Any]):
         self.for_machine = self.get_for_machine_from_kwargs(kwargs)

mesonbuild/interpreter/interpreter.py

@@ -2165,10 +2165,11 @@ class Interpreter(InterpreterBase, HoldableObject):
         return tg
 
     @FeatureNew('alias_target', '0.52.0')
-    @typed_pos_args('alias_target', str, varargs=build.Target, min_varargs=1)
+    @typed_pos_args('alias_target', str, varargs=(build.Target, build.BothLibraries), min_varargs=1)
     @noKwargs
-    def func_alias_target(self, node: mparser.BaseNode, args: T.Tuple[str, T.List[build.Target]],
-                          kwargs: 'TYPE_kwargs') -> build.AliasTarget:
+    @noSecondLevelHolderResolving
+    def func_alias_target(self, node: mparser.BaseNode, args: T.Tuple[str, T.List[T.Union[build.Target, build.BothLibraries]]],
+                          kwargs: TYPE_kwargs) -> build.AliasTarget:
         name, deps = args
         if any(isinstance(d, build.RunTarget) for d in deps):
             FeatureNew.single_use('alias_target that depends on run_targets', '0.60.0', self.subproject)

mesonbuild/interpreter/interpreterobjects.py

@@ -41,6 +41,10 @@ if T.TYPE_CHECKING:
 
         separator: str
 
+    class InternalDependencyAsKW(TypedDict):
+
+        recursive: bool
+
 _ERROR_MSG_KW: KwargInfo[T.Optional[str]] = KwargInfo('error_message', (str, NoneType))
 
 
@@ -462,6 +466,8 @@ class DependencyHolder(ObjectHolder[Dependency]):
                              'include_type': self.include_type_method,
                              'as_system': self.as_system_method,
                              'as_link_whole': self.as_link_whole_method,
+                             'as_static': self.as_static_method,
+                             'as_shared': self.as_shared_method,
                              })
 
     def found(self) -> bool:
@@ -580,6 +586,28 @@ class DependencyHolder(ObjectHolder[Dependency]):
         new_dep = self.held_object.generate_link_whole_dependency()
         return new_dep
 
+    @FeatureNew('dependency.as_static', '1.6.0')
+    @noPosargs
+    @typed_kwargs(
+        'dependency.as_static',
+        KwargInfo('recursive', bool, default=False),
+    )
+    def as_static_method(self, args: T.List[TYPE_var], kwargs: InternalDependencyAsKW) -> Dependency:
+        if not isinstance(self.held_object, InternalDependency):
+            raise InterpreterException('as_static method is only supported on declare_dependency() objects')
+        return self.held_object.get_as_static(kwargs['recursive'])
+
+    @FeatureNew('dependency.as_shared', '1.6.0')
+    @noPosargs
+    @typed_kwargs(
+        'dependency.as_shared',
+        KwargInfo('recursive', bool, default=False),
+    )
+    def as_shared_method(self, args: T.List[TYPE_var], kwargs: InternalDependencyAsKW) -> Dependency:
+        if not isinstance(self.held_object, InternalDependency):
+            raise InterpreterException('as_shared method is only supported on declare_dependency() objects')
+        return self.held_object.get_as_shared(kwargs['recursive'])
+
 _EXTPROG = T.TypeVar('_EXTPROG', bound=ExternalProgram)
 
 class _ExternalProgramHolder(ObjectHolder[_EXTPROG]):

test cases/common/178 bothlibraries/meson.build

@@ -2,6 +2,7 @@ project('both libraries linking test', 'c', 'cpp')
 
 both_libs = both_libraries('mylib', 'libfile.c')
 dep = declare_dependency(link_with: both_libs)
+alias_target('alias', both_libs)
 exe_shared = executable('prog-shared', 'main.c', link_with : both_libs.get_shared_lib())
 exe_static = executable('prog-static', 'main.c',
                         c_args : ['-DSTATIC_COMPILATION'],

test cases/common/273 both libraries/meson.build

@@ -77,11 +77,37 @@ test('test both libs', main)
 if get_option('default_library') == 'both' and get_option('default_both_libraries') == 'auto'
     # With those options, even if the both_libraries defaults to 'shared',
     # 'static' version is used when linking to the static part of another both_libraries.
+
+    if get_option('use_dep')
+        main_static_deps = [with_library_dep.as_static(recursive: true)]
+        main_static_links = []
+    else
+        main_static_deps = []
+        main_static_links = [with_library.get_static_lib()]
+    endif
     main_static = executable(
         'main_static',
         files('src/main.c'),
         c_args: [f'-DEXPECTED=0'],
-        link_with: with_library.get_static_lib(),
+        link_with: main_static_links,
+        dependencies: main_static_deps,
     )
     test('test static', main_static)
+
+
+    if get_option('use_dep')
+        main_shared_deps = [with_library_dep.as_shared(recursive: true)]
+        main_shared_links = []
+    else
+        main_shared_deps = []
+        main_shared_links = [with_library.get_shared_lib()]
+    endif
+    main_shared = executable(
+        'main_shared',
+        files('src/main.c'),
+        c_args: [f'-DEXPECTED=2'],
+        link_with: main_shared_links,
+        dependencies: main_shared_deps,
+    )
+    test('test shared', main_shared)
 endif