fix: drop collapsed import self-loops

graphify/build.py

@@ -767,6 +767,16 @@ def build_from_json(extraction: dict, *, directed: bool = False, root: str | Pat
                 # (unknown ext, e.g. a manifest) is never mistaken for a phantom.
                 if src_fam is not None and tgt_fam is not None and src_fam != tgt_fam:
                     continue
+        # A file-level import or re-export cannot carry useful connectivity when
+        # both endpoints resolve to the same node.  This most often happens when
+        # the target is an unresolved bare module name (``builtins``, ``poseidon``)
+        # that the legacy-ID alias index above mistakes for the importing file's
+        # own old stem.  It also covers a nested module importing its parent file:
+        # at file-node granularity that relationship necessarily collapses.  Keep
+        # other self-edges, notably recursive ``calls``, because those are real
+        # program structure rather than import-resolution artifacts.
+        if src == tgt and _edge_rel in ("imports", "imports_from", "re_exports"):
+            continue
         # Preserve original edge direction - undirected graphs lose it otherwise,
         # causing display functions to show edges backwards.
         attrs["_src"] = src

tests/test_import_self_loops.py

@@ -0,0 +1,107 @@
+from pathlib import Path
+
+import pytest
+
+from graphify.build import build_from_json
+from graphify.extract import extract
+
+
+def _write(path: Path, source: str) -> Path:
+    path.parent.mkdir(parents=True, exist_ok=True)
+    path.write_text(source, encoding="utf-8")
+    return path
+
+
+def _import_self_loops(result: dict) -> list[dict]:
+    return [
+        edge
+        for edge in result["edges"]
+        if edge.get("relation") in {"imports", "imports_from", "re_exports"}
+        and edge.get("source") == edge.get("target")
+    ]
+
+
+def _built_import_self_loops(result: dict) -> list[tuple[str, str, dict]]:
+    graph = build_from_json(result, directed=True)
+    return [
+        (source, target, data)
+        for source, target, data in graph.edges(data=True)
+        if source == target
+        and data.get("relation") in {"imports", "imports_from", "re_exports"}
+    ]
+
+
+@pytest.mark.parametrize(
+    ("relative_path", "source"),
+    [
+        ("src/contracting/stdlib/builtins.py", "import builtins\n"),
+        ("playground/services/contracting.py", "from contracting import constants\n"),
+    ],
+)
+def test_python_external_import_matching_current_basename_has_no_self_loop(
+    tmp_path: Path,
+    relative_path: str,
+    source: str,
+) -> None:
+    module = _write(tmp_path / relative_path, source)
+
+    result = extract([module], cache_root=tmp_path, parallel=False)
+
+    assert _import_self_loops(result) == []
+    assert _built_import_self_loops(result) == []
+
+
+@pytest.mark.parametrize(
+    ("relative_path", "source"),
+    [
+        (
+            "packages/compiler/src/fixture.rs",
+            "mod tests { use crate::fixture::Fixture; }\n",
+        ),
+        (
+            "packages/zk/src/poseidon.rs",
+            "use ark_crypto_primitives::sponge::poseidon::{PoseidonConfig, PoseidonSponge};\n",
+        ),
+    ],
+)
+def test_rust_import_matching_current_basename_has_no_self_loop(
+    tmp_path: Path,
+    relative_path: str,
+    source: str,
+) -> None:
+    module = _write(tmp_path / relative_path, source)
+
+    result = extract([module], cache_root=tmp_path, parallel=False)
+
+    assert _import_self_loops(result) == []
+    assert _built_import_self_loops(result) == []
+
+
+def test_recursive_call_self_loop_is_preserved() -> None:
+    result = {
+        "nodes": [
+            {
+                "id": "module_recurse",
+                "label": "recurse()",
+                "file_type": "code",
+                "source_file": "module.py",
+                "source_location": "L1",
+                "_origin": "ast",
+            }
+        ],
+        "edges": [
+            {
+                "source": "module_recurse",
+                "target": "module_recurse",
+                "relation": "calls",
+                "confidence": "EXTRACTED",
+                "source_file": "module.py",
+                "source_location": "L2",
+            }
+        ],
+    }
+
+    graph = build_from_json(result, directed=True)
+
+    assert graph.has_edge("module_recurse", "module_recurse")
+    assert graph["module_recurse"]["module_recurse"]["relation"] == "calls"