cargo: define 'features' variable to be used in meson/meson.build

Author: xclaesse

docs/markdown/Wrap-dependency-system-manual.md

@@ -362,6 +362,8 @@ Some naming conventions need to be respected:
   This is typically used as `extra_args += ['--cfg', 'foo']`.
 - The `extra_deps` variable is pre-defined and can be used to add extra dependencies.
   This is typically used as `extra_deps += dependency('foo')`.
+- The `features` variable is pre-defined and contains the list of features enabled
+  on this crate.
 
 Since *1.5.0* Cargo wraps can also be provided with `Cargo.lock` file at the root
 of (sub)project source tree. Meson will automatically load that file and convert

mesonbuild/cargo/interpreter.py

@@ -129,9 +129,10 @@ def interpret_package(self, manifest: Manifest, build: builder.Builder, subdir:
 
     def _create_package(self, pkg: PackageState, build: builder.Builder, subdir: str) -> T.List[mparser.BaseNode]:
         ast: T.List[mparser.BaseNode] = [
+            build.assign(build.array([build.string(f) for f in pkg.features]), 'features'),
             build.function('message', [
                 build.string('Enabled features:'),
-                build.array([build.string(f) for f in pkg.features]),
+                build.identifier('features'),
             ]),
         ]
         ast += self._create_dependencies(pkg, build)