allow rust hooks to specify crate features

Now the rust hooks can use the parameter `additional_dependencies` to
receive build-time features for the crate.

The features must start with the string "--feature=" following the name
of the feature; e.g. "--feature=full".

Fixes #3230

pre_commit/languages/rust.py

@@ -22,6 +22,7 @@ from pre_commit.util import make_executable
 from pre_commit.util import win_exe
 
 ENVIRONMENT_DIR = 'rustenv'
+FEATURE_PREFIX = '--feature='
 health_check = lang_base.basic_health_check
 run_hook = lang_base.basic_run_hook
 
@@ -73,6 +74,8 @@ def _add_dependencies(
 ) -> None:
     crates = []
     for dep in additional_dependencies:
+        if dep.startswith(FEATURE_PREFIX):
+            continue
         name, _, spec = dep.partition(':')
         crate = f'{name}@{spec or "*"}'
         crates.append(crate)
@@ -130,6 +133,12 @@ def install_environment(
     cli_deps = {
         dep for dep in additional_dependencies if dep.startswith('cli:')
     }
+    # Features starts with "--feature="
+    features = {
+        dep.replace(FEATURE_PREFIX, '')
+        for dep in additional_dependencies
+        if dep.startswith('--')
+    }
     lib_deps = set(additional_dependencies) - cli_deps
 
     packages_to_install: set[tuple[str, ...]] = {('--path', '.')}
@@ -153,8 +162,13 @@ def install_environment(
         if len(lib_deps) > 0:
             _add_dependencies(prefix, lib_deps)
 
+        features_params = []
+        if features:
+            features_params = ['--features', *features]
+
         for args in packages_to_install:
             cmd_output_b(
                 'cargo', 'install', '--bins', '--root', envdir, *args,
+                *features_params,
                 cwd=prefix.prefix_dir,
             )

tests/languages/rust_test.py

@@ -44,13 +44,19 @@ def _make_hello_world(tmp_path):
     src_dir.joinpath('main.rs').write_text(
         'fn main() {\n'
         '    println!("Hello, world!");\n'
+        '    if cfg!(feature = "foo") {\n'
+        '        println!("With feature foo");\n'
+        '    }\n'
         '}\n',
     )
     tmp_path.joinpath('Cargo.toml').write_text(
         '[package]\n'
         'name = "hello_world"\n'
         'version = "0.1.0"\n'
-        'edition = "2021"\n',
+        'edition = "2021"\n'
+        '\n'
+        '[features]\n'
+        'foo = []\n',
     )
 
 
@@ -113,3 +119,12 @@ def test_run_lib_additional_dependencies(tmp_path):
     assert bin_dir.is_dir()
     assert not bin_dir.joinpath('shellharden').exists()
     assert not bin_dir.joinpath('shellharden.exe').exists()
+
+
+def test_run_features_additional_dependencies(tmp_path):
+    _make_hello_world(tmp_path)
+
+    deps = ('shellharden:4.2.0', 'git-version')
+    features = ('--feature=foo',)
+    ret = run_language(tmp_path, rust, 'hello_world', deps=deps + features)
+    assert ret == (0, b'Hello, world!\nWith feature foo\n')