Add methods to BuildTargets for vala generated targets

docs/markdown/Vala.md

@@ -304,6 +304,40 @@ In this example, the second and third elements of the `install_dir`
 array indicate the destination with `true` to use default directories
 (i.e. `include` and `share/vala/vapi`).
 
+### Depending on C header
+
+*(since 1.10.0)*
+
+Given the previous example,
+
+```meson
+foo_lib = shared_library(...)
+foo_h = foo_lib.vala_header()
+```
+
+This header can now be used like any other generated header to create an
+order-only dependency.
+
+
+### Depending on VAPI header
+
+*(since 1.10.0)*
+
+Given the previous example,
+
+```meson
+foo_lib = shared_library(...)
+foo_vapi = foo_lib.vala_vapi()
+```
+
+### Depending on generated GIR
+
+*(since 1.10.0)*
+
+```meson
+foo_lib = shared_library(..., vala_gir : 'foo.gir')
+foo_gir = foo_lib.vala_gir()
+```
 
 ### GObject Introspection and language bindings
 
@@ -339,6 +373,21 @@ directory (i.e. `share/gir-1.0` for GIRs). The fourth element in the
 To then generate a typelib file use a custom target with the
 `g-ir-compiler` program and a dependency on the library:
 
+*Since Meson 1.10*, use the `.vala_gir()` method to get a handle to the generated `.gir` file:
+
+```meson
+g_ir_compiler = find_program('g-ir-compiler')
+custom_target('foo typelib', command: [g_ir_compiler, '--output', '@OUTPUT@', '@INPUT@'],
+              input: foo_lib.vala_gir(),
+              output: 'Foo-1.0.typelib',
+              install: true,
+              install_dir: get_option('libdir') / 'girepository-1.0')
+```
+
+
+*Before Meson 1.10*, calculating the path to the input is required, as is adding a
+manual dependency to the vala target:
+
 ```meson
 g_ir_compiler = find_program('g-ir-compiler')
 custom_target('foo typelib', command: [g_ir_compiler, '--output', '@OUTPUT@', '@INPUT@'],

docs/markdown/snippets/vala-target-extra-methods.md

@@ -0,0 +1,21 @@
+## Vala BuildTarget dependency enhancements
+
+A BuildTarget that has Vala sources can now get a File dependency for its
+generated header, vapi, and gir files.
+
+```meson
+lib = library('foo', 'foo.vala')
+lib_h = lib.vala_header()
+lib_s = static_lib('static', 'static.c', lib_h)
+
+lib_vapi = lib.vala_vapi()
+
+custom_target(
+  'foo-typelib',
+  command : ['g-ir-compiler', '--output', '@OUTPUT@', '@INPUT@'],
+  input : lib.vala_gir(),
+  output : 'Foo-1.0.typelib'
+)
+```
+
+`static.c` will not start compilation until `lib.h` is generated.

docs/yaml/objects/build_tgt.yaml

@@ -77,3 +77,27 @@ methods:
     objects feature compatible with [[@external_program]] objects. This
     simplifies use-cases where an executable is used instead of
     an [[@external_program]].
+
+- name: vala_header
+  returns: file
+  since: 1.10.0
+  description: |
+    Returns a [[@file]] object pointing to a C compatible header generated by
+    the vala compiler, if this target does not generate a vala header then it is
+    an error to call this method.
+
+- name: vala_vapi
+  returns: file
+  since: 1.10.0
+  description: |
+    Returns a [[@file]] object pointing to a VAPI header generated by the vala
+    compiler, if this target does not generate a VAPI file then it is an error
+    to call this method.
+
+- name: vala_gir
+  returns: file
+  since: 1.10.0
+  description: |
+    Returns a [[@file]] object pointing to a GIR file generated by the vala
+    compiler, if this target does not generate a GIR file then it is an error
+    to call this method.

mesonbuild/interpreter/interpreterobjects.py

@@ -988,6 +988,43 @@ def get_id_method(self, args: T.List[TYPE_var], kwargs: TYPE_kwargs) -> str:
     def name_method(self, args: T.List[TYPE_var], kwargs: TYPE_kwargs) -> str:
         return self._target_object.name
 
+    @FeatureNew('vala_header', '1.10.0')
+    @noPosargs
+    @noKwargs
+    @InterpreterObject.method('vala_header')
+    def vala_header_method(self, args: T.List[TYPE_var], kwargs: TYPE_kwargs) -> mesonlib.File:
+        if not hasattr(self._target_object, 'vala_header'):
+            raise mesonlib.MesonException("Attempted to get a Vala header from a target that doesn't generate one")
+
+        assert self.interpreter.backend is not None, 'for mypy'
+        return mesonlib.File.from_built_file(
+            self.interpreter.backend.get_target_dir(self._target_object), self._target_object.vala_header)
+
+    @FeatureNew('vala_vapi', '1.10.0')
+    @noPosargs
+    @noKwargs
+    @InterpreterObject.method('vala_vapi')
+    def vala_vapi_method(self, args: T.List[TYPE_var], kwargs: TYPE_kwargs) -> mesonlib.File:
+        if not hasattr(self._target_object, 'vala_vapi'):
+            raise mesonlib.MesonException("Attempted to get a Vala VAPI from a target that doesn't generate one")
+
+        assert self.interpreter.backend is not None, 'for mypy'
+        return mesonlib.File.from_built_file(
+            self.interpreter.backend.get_target_dir(self._target_object), self._target_object.vala_vapi)
+
+    @FeatureNew('vala_gir', '1.10.0')
+    @noPosargs
+    @noKwargs
+    @InterpreterObject.method('vala_gir')
+    def vala_gir_method(self, args: T.List[TYPE_var], kwargs: TYPE_kwargs) -> mesonlib.File:
+        if not hasattr(self._target_object, 'vala_gir'):
+            raise mesonlib.MesonException("Attempted to get a Vala GIR from a target that doesn't generate one")
+
+        assert self.interpreter.backend is not None, 'for mypy'
+        return mesonlib.File.from_built_file(
+            self.interpreter.backend.get_target_dir(self._target_object), self._target_object.vala_gir)
+
+
 class ExecutableHolder(BuildTargetHolder[build.Executable]):
     pass
 

test cases/vala/9 gir/meson.build

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: Apache-2.0
+# Copyright © 2025 Intel Corporation
+
 project('foo', 'c', 'vala')
 
 glib = dependency('glib-2.0')
@@ -12,6 +15,6 @@ foo = shared_library('foo', 'foo.vala',
 
 custom_target('foo-typelib',
               command: [g_ir_compiler, '--output', '@OUTPUT@', '@INPUT@'],
-              input: meson.current_build_dir() + '/Foo-1.0.gir',
+              input: foo.vala_gir(),
               output: 'Foo-1.0.typelib',
-              depends: foo)
+              build_by_default : true)