fix(cargo): honor package = "..." rename when resolving internal deps (#1858)

graphify/cargo_introspect.py

@@ -78,8 +78,19 @@ def introspect_cargo(root: str | Path) -> dict[str, Any]:
         if not isinstance(dependencies, dict):
             continue
         source_file = manifest.relative_to(root_path).as_posix()
-        for dependency_name in sorted(dependencies):
-            target = crates.get(dependency_name)
+        for dep_key, spec in sorted(dependencies.items()):
+            # Cargo lets a dep table entry rename the crate via `package = "..."`:
+            #   db = { path = "../storage", package = "internal-storage" }
+            # The key `db` is the name used in `use db::…;`; the actual crate
+            # published under `[package].name = "internal-storage"` is what
+            # `crates` is keyed by. Without honoring `package`, every renamed
+            # workspace-internal dep silently drops its edge (#1858).
+            real_name = dep_key
+            if isinstance(spec, dict):
+                pkg_override = spec.get("package")
+                if isinstance(pkg_override, str) and pkg_override:
+                    real_name = pkg_override
+            target = crates.get(real_name)
             if target is None:
                 continue
             edges.append(

tests/test_cargo_introspect.py

@@ -363,3 +363,95 @@ edition = "2021"{dependency_block}
         "source_file": "crates/crate_198/Cargo.toml",
         "source_location": "L1",
     } in result["edges"]
+
+
+def test_cargo_introspect_honors_package_rename_on_internal_dep(tmp_path):
+    """Renamed workspace-internal deps still produce a `crate_depends_on` edge (#1858).
+
+    Cargo's `package = "..."` inside a dep table entry lets the key used in
+    `use db::…;` differ from the crate's real `[package].name`. Looking up
+    `crates` by the raw dep-table key misses the rename and silently drops
+    the edge.
+    """
+    _write_manifest(
+        tmp_path / "Cargo.toml",
+        """
+[workspace]
+members = ["app", "storage"]
+""",
+    )
+    app = tmp_path / "app"
+    storage = tmp_path / "storage"
+    app.mkdir()
+    storage.mkdir()
+    _write_manifest(
+        app / "Cargo.toml",
+        """
+[package]
+name = "app"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+db = { path = "../storage", package = "internal-storage" }
+""",
+    )
+    _write_manifest(
+        storage / "Cargo.toml",
+        """
+[package]
+name = "internal-storage"
+version = "0.1.0"
+edition = "2021"
+""",
+    )
+
+    result = introspect_cargo(tmp_path)
+
+    node_ids = {node["id"] for node in result["nodes"]}
+    assert node_ids == {"crate:app", "crate:internal-storage"}
+    assert {
+        "source": "crate:app",
+        "target": "crate:internal-storage",
+        "relation": "crate_depends_on",
+        "context": "cargo_dependency",
+        "weight": 1.0,
+        "confidence": "EXTRACTED",
+        "source_file": "app/Cargo.toml",
+        "source_location": "L1",
+    } in result["edges"]
+
+
+def test_cargo_introspect_package_rename_falls_through_when_unresolved(tmp_path):
+    """A rename pointing at an external (non-workspace) crate stays a no-op.
+
+    Guards against the fix silently emitting edges to registry crates: the
+    resolved name still has to appear in `crates` (the workspace-internal
+    index) for an edge to be produced.
+    """
+    _write_manifest(
+        tmp_path / "Cargo.toml",
+        """
+[workspace]
+members = ["app"]
+""",
+    )
+    app = tmp_path / "app"
+    app.mkdir()
+    _write_manifest(
+        app / "Cargo.toml",
+        """
+[package]
+name = "app"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+tokio_rt = { version = "1", package = "tokio" }
+""",
+    )
+
+    result = introspect_cargo(tmp_path)
+
+    assert {node["id"] for node in result["nodes"]} == {"crate:app"}
+    assert result["edges"] == []