Merge pull request #60 from Point72/tkp/libskip

Add skip-if-env gating for individual Rust artifacts

Author: timkpaine

.gitignore

@@ -155,3 +155,7 @@ ROADMAP.md
 AGENTS.md
 .github/hooks/sdlc.json
 .superpowers
+
+# Generated by test_project_generated_files fixture during the test suite
+hatch_rs/tests/test_project_generated_files/generated_files_project/generated/
+hatch_rs/tests/test_project_generated_files/generated_files_project/include/

hatch_rs/structs.py

@@ -114,6 +114,13 @@ class CopiedArtifact:
 }
 
 
+def _env_truthy(value: Optional[str]) -> bool:
+    """Return True when an environment variable value reads as enabled/truthy."""
+    if value is None:
+        return False
+    return value.strip().lower() not in ("", "0", "false", "no", "off")
+
+
 def _normalize_machine(machine: str) -> str:
     normalized = machine.lower().replace("-", "_")
     aliases = {
@@ -392,6 +399,11 @@ class RustArtifactConfig(BaseModel):
     model_config = ConfigDict(extra="ignore", populate_by_name=True)
 
     name: Optional[str] = Field(default=None, description="Cargo artifact name used for exact artifact discovery and errors.")
+    skip_if_env: Optional[str] = Field(
+        default=None,
+        alias="skip-if-env",
+        description="Skip building and packaging this artifact when the named environment variable is set to a truthy value.",
+    )
     manifest: Optional[Path] = Field(default=None, description="Path to Cargo.toml, relative to the hook path unless absolute.")
     build_type: Optional[BuildType] = Field(default=None, alias="build-type")
     profile: Optional[str] = Field(default=None, description="Cargo profile for this artifact.")
@@ -651,9 +663,12 @@ def shared_data(self) -> dict[str, str]:
     def resolved_target(self) -> Optional[ResolvedTarget]:
         return self._resolved_target
 
+    def _artifact_skipped(self, artifact: RustArtifactConfig) -> bool:
+        return artifact.skip_if_env is not None and _env_truthy(environ.get(artifact.skip_if_env))
+
     def _configured_artifacts(self) -> list[RustArtifactConfig]:
         if self.artifacts:
-            return list(self.artifacts)
+            return [artifact for artifact in self.artifacts if not self._artifact_skipped(artifact)]
         return [RustArtifactConfig(destination=f"{self.module}/{{python_extension_name}}")]
 
     def _artifact_label(self, artifact: RustArtifactConfig) -> str:

hatch_rs/tests/test_structs.py

@@ -206,6 +206,44 @@ def test_build_plan_generates_explicit_artifacts(tmp_path):
     plan.cleanup()
 
 
+def test_build_plan_skips_artifact_when_skip_if_env_is_truthy(tmp_path, monkeypatch):
+    plan = HatchRustBuildPlan(
+        module="project",
+        path=tmp_path,
+        target="x86_64-unknown-linux-gnu",
+        target_dir="isolated",
+        artifacts=[
+            {
+                "name": "project",
+                "manifest": "Cargo.toml",
+                "destination": "{module}/{python_extension_name}",
+            },
+            {
+                "name": "project_ffi",
+                "manifest": "rust/Cargo.toml",
+                "destination": "{module}/lib/{shared_library}",
+                "skip-if-env": "PROJECT_SKIP_SHARED_LIBRARY",
+            },
+        ],
+    )
+
+    monkeypatch.delenv("PROJECT_SKIP_SHARED_LIBRARY", raising=False)
+    assert plan.generate() == [
+        "cargo rustc --manifest-path Cargo.toml --release --target x86_64-unknown-linux-gnu -- --crate-type cdylib",
+        "cargo rustc --manifest-path rust/Cargo.toml --release --target x86_64-unknown-linux-gnu -- --crate-type cdylib",
+    ]
+
+    monkeypatch.setenv("PROJECT_SKIP_SHARED_LIBRARY", "1")
+    assert plan.generate() == [
+        "cargo rustc --manifest-path Cargo.toml --release --target x86_64-unknown-linux-gnu -- --crate-type cdylib",
+    ]
+
+    monkeypatch.setenv("PROJECT_SKIP_SHARED_LIBRARY", "0")
+    assert len(plan.generate()) == 2
+
+    plan.cleanup()
+
+
 def test_build_plan_copies_shared_library_to_tokenized_destination(tmp_path):
     plan = HatchRustBuildPlan(
         module="project",