modules/rust: Add a `link_with` kwarg to the test method

This was requested by Mesa, where a bunch of `declare_dependency`
objects are being created as a workaround for the lack of this keyword

6 files changed, 41 insertions, 4 deletions

diff --git a/docs/markdown/Rust-module.md b/docs/markdown/Rust-module.md
index 7617dbb..512c4ec 100644
--- a/docs/markdown/Rust-module.md
+++ b/docs/markdown/Rust-module.md
@@ -18,7 +18,7 @@ like Meson, rather than Meson work more like rust.
 
 ## Functions
 
-### test(name: string, target: library | executable, dependencies: []Dependency)
+### test(name: string, target: library | executable, dependencies: []Dependency, link_with: []targets)
 
 This function creates a new rust unittest target from an existing rust
 based target, which may be a library or executable. It does this by
@@ -33,6 +33,9 @@ that automatically.
 Additional, test only dependencies may be passed via the dependencies
 argument.
 
+*(since 1.2.0)* the link_with argument can be used to pass additional build
+targets to link with
+
 ### bindgen(*, input: string | BuildTarget | [](string | BuildTarget), output: string, include_directories: [](include_directories | string), c_args: []string, args: []string, dependencies: []Dependency)
 
 This function wraps bindgen to simplify creating rust bindings around C
diff --git a/docs/markdown/snippets/rust_test_link_with.md b/docs/markdown/snippets/rust_test_link_with.md
new file mode 100644
index 0000000..9c2b7d6
--- /dev/null
+++ b/docs/markdown/snippets/rust_test_link_with.md
@@ -0,0 +1,4 @@
+## Add a `link_with` keyword to `rust.test()`
+
+This can already be be worked around by creating `declare_dependency()` objects
+to pass to the `dependencies` keyword, but this cuts out the middle man.
diff --git a/mesonbuild/modules/rust.py b/mesonbuild/modules/rust.py
index bf1fd1d..4153630 100644
--- a/mesonbuild/modules/rust.py
+++ b/mesonbuild/modules/rust.py
@@ -1,4 +1,4 @@
-# Copyright © 2020-2022 Intel Corporation
+# Copyright © 2020-2023 Intel Corporation
 
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -18,15 +18,16 @@ import typing as T
 
 from . import ExtensionModule, ModuleReturnValue, ModuleInfo
 from .. import mlog
-from ..build import BothLibraries, BuildTarget, CustomTargetIndex, Executable, ExtractedObjects, GeneratedList, IncludeDirs, CustomTarget, StructuredSources
+from ..build import BothLibraries, BuildTarget, CustomTargetIndex, Executable, ExtractedObjects, GeneratedList, IncludeDirs, CustomTarget, InvalidArguments, Jar, StructuredSources
 from ..compilers.compilers import are_asserts_disabled
 from ..dependencies import Dependency, ExternalLibrary
-from ..interpreter.type_checking import DEPENDENCIES_KW, TEST_KWS, OUTPUT_KW, INCLUDE_DIRECTORIES
+from ..interpreter.type_checking import DEPENDENCIES_KW, LINK_WITH_KW, TEST_KWS, OUTPUT_KW, INCLUDE_DIRECTORIES
 from ..interpreterbase import ContainerTypeInfo, InterpreterException, KwargInfo, typed_kwargs, typed_pos_args, noPosargs
 from ..mesonlib import File
 
 if T.TYPE_CHECKING:
     from . import ModuleState
+    from ..build import LibTypes
     from ..interpreter import Interpreter
     from ..interpreter import kwargs as _kwargs
     from ..interpreter.interpreter import SourceInputs, SourceOutputs
@@ -38,6 +39,7 @@ if T.TYPE_CHECKING:
 
         dependencies: T.List[T.Union[Dependency, ExternalLibrary]]
         is_parallel: bool
+        link_with: T.List[LibTypes]
 
     class FuncBindgen(TypedDict):
 
@@ -68,6 +70,7 @@ class RustModule(ExtensionModule):
         'rust.test',
         *TEST_KWS,
         DEPENDENCIES_KW,
+        LINK_WITH_KW.evolve(since='1.2.0'),
         KwargInfo('is_parallel', bool, default=False),
     )
     def test(self, state: ModuleState, args: T.Tuple[str, BuildTarget], kwargs: FuncTest) -> ModuleReturnValue:
@@ -112,6 +115,9 @@ class RustModule(ExtensionModule):
         rust.test('rust_lib_test', rust_lib)
         ```
         """
+        if any(isinstance(t, Jar) for t in kwargs.get('link_with', [])):
+            raise InvalidArguments('Rust tests cannot link with Jar targets')
+
         name = args[0]
         base_target: BuildTarget = args[1]
         if not base_target.uses_rust():
@@ -145,6 +151,7 @@ class RustModule(ExtensionModule):
         new_target_kwargs['rust_args'] = new_target_kwargs.get('rust_args', []) + ['--test']
         new_target_kwargs['install'] = False
         new_target_kwargs['dependencies'] = new_target_kwargs.get('dependencies', []) + kwargs['dependencies']
+        new_target_kwargs['link_with'] = new_target_kwargs.get('link_with', []) + kwargs['link_with']
 
         sources = T.cast('T.List[SourceOutputs]', base_target.sources.copy())
         sources.extend(base_target.generated)
diff --git a/test cases/rust/9 unit tests/helper.rs b/test cases/rust/9 unit tests/helper.rs
new file mode 100644
index 0000000..afe3233
--- /dev/null
+++ b/test cases/rust/9 unit tests/helper.rs
@@ -0,0 +1,3 @@
+pub fn subtract(a: i32, b: i32) -> i32 {
+        a - b
+}
diff --git a/test cases/rust/9 unit tests/meson.build b/test cases/rust/9 unit tests/meson.build
index b649abb..9096014 100644
--- a/test cases/rust/9 unit tests/meson.build
+++ b/test cases/rust/9 unit tests/meson.build
@@ -41,3 +41,7 @@ rust.test('rust_test_from_static', lib, args: ['--skip', 'test_add_intentional_f
 
 lib = shared_library('rust_shared', ['test.rs'])
 rust.test('rust_test_from_shared', lib, args: ['--skip', 'test_add_intentional_fail'])
+
+helper = static_library('helper', 'helper.rs')
+lib = static_library('rust_link_with', 'test3.rs')
+rust.test('rust_test_link_with', lib, link_with : helper)
diff --git a/test cases/rust/9 unit tests/test3.rs b/test cases/rust/9 unit tests/test3.rs
new file mode 100644
index 0000000..ccb5f98
--- /dev/null
+++ b/test cases/rust/9 unit tests/test3.rs
@@ -0,0 +1,16 @@
+pub fn add(a: i32, b: i32) -> i32 {
+    a + b
+}
+
+#[cfg(test)]
+mod tests {
+        extern crate helper;
+
+        use super::*;
+
+        #[test]
+        fn test_add_sub() {
+                let x = helper::subtract(6, 5);
+                assert_eq!(add(x, 5), 6);
+        }
+}