fix: symmetric move detection in PR-review rules

CHANGELOG.md

@@ -131,6 +131,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   every caller updated was flagged critical three times. Genuine
   deletions with surviving callers still fire. (Both surfaced by the
   self-review gate on the wave-2 dashboard/resolver PRs.)
+  Move detection is symmetric since the follow-up: `new-untested-hotspot`
+  and `new-dead-code` likewise skip ADDED symbols whose terminal name
+  exists in the removed set — a relocated function is not new code, so
+  its pre-existing coverage state doesn't gate the PR that moved it
+  (`formatQn` was flagged as a "new" untested hotspot by the same
+  app.js split).
 - **`codegraph init` now writes a robust `.mcp.json`** — uses the absolute
   path to the `codegraph` binary (resolved from the running interpreter's
   bin dir, then `shutil.which`, then bare fallback), passes an explicit

codegraph/review/rules.py

@@ -235,6 +235,20 @@ def evaluate_rules(
     findings: list[Finding] = []
     cycle_introduced = _introduces_cycle(new_graph, old_graph, cycle_cache)
 
+    # Move detection: a symbol removed at one qualname and added at another
+    # with the same terminal name and kind was relocated, not deleted/created.
+    # Removed-side rules skip when the name reappears in the added set;
+    # added-side "new code" rules skip when it came from the removed set.
+    added_names = {
+        (c.qualname.rsplit(".", 1)[-1], c.kind) for c in diff.added_nodes
+    }
+    removed_names = {
+        (c.qualname.rsplit(".", 1)[-1], c.kind) for c in diff.removed_nodes
+    }
+
+    def _is_moved(change: NodeChange, counterpart: set[tuple[str, str]]) -> bool:
+        return (change.qualname.rsplit(".", 1)[-1], change.kind) in counterpart
+
     for rule in rules:
         when = rule.when
         if when == "added_node":
@@ -275,19 +289,12 @@ def evaluate_rules(
                     )
                 )
         elif when == "removed_referenced":
-            # A removed symbol whose terminal name reappears in the added
-            # set (same kind) was moved, not deleted — callers reference the
-            # new location. PR #73 flagged esc/pyvisHref as critical after
-            # they moved from app.js to ui/helpers.js with all callers
-            # updated.
-            moved = {
-                (c.qualname.rsplit(".", 1)[-1], c.kind)
-                for c in diff.added_nodes
-            }
+            # PR #73 flagged esc/pyvisHref as critical after they moved
+            # from app.js to ui/helpers.js with all callers updated.
             for change in diff.removed_nodes:
                 if not _node_matches(rule, change):
                     continue
-                if (change.qualname.rsplit(".", 1)[-1], change.kind) in moved:
+                if _is_moved(change, added_names):
                     continue
                 old_id = _find_node_id(change.qualname, change.kind, old_graph)
                 if old_id is None:
@@ -324,6 +331,8 @@ def evaluate_rules(
                     continue
                 if change.kind not in ("FUNCTION", "METHOD"):
                     continue
+                if _is_moved(change, removed_names):
+                    continue
                 new_id = _find_node_id(change.qualname, change.kind, new_graph)
                 if new_id is None:
                     continue
@@ -347,6 +356,11 @@ def evaluate_rules(
                     NodeKind.METHOD.value,
                 ):
                     continue
+                # A moved symbol is not NEW code — its (lack of) test
+                # coverage predates the PR. PR #73 flagged formatQn as a
+                # new untested hotspot after it moved app.js -> helpers.js.
+                if _is_moved(change, removed_names):
+                    continue
                 new_id = _find_node_id(change.qualname, change.kind, new_graph)
                 if new_id is None:
                     continue

tests/test_review_rules.py

@@ -153,3 +153,57 @@ def test_removed_referenced_still_fires_for_real_removal() -> None:
     diff = diff_graphs(old_g, new_g)
     findings = evaluate_rules(diff, new_graph=new_g, old_graph=old_g)
     assert [f for f in findings if f.rule_id == "removed-referenced"]
+
+
+def test_new_untested_hotspot_skips_moved_symbol() -> None:
+    """Regression test: a symbol that MOVED modules is not NEW code — its
+    test-coverage state predates the PR. PR #73 flagged formatQn as a new
+    untested hotspot after it moved from app.js to ui/helpers.js."""
+    old_g: nx.MultiDiGraph = nx.MultiDiGraph()
+    new_g: nx.MultiDiGraph = nx.MultiDiGraph()
+    _add_fn(old_g, "pkg.app.formatQn", file="app.js")
+    _add_fn(new_g, "pkg.ui.helpers.formatQn", file="ui/helpers.js")
+    # Give the moved symbol >= 5 non-test callers in the new graph.
+    for i in range(5):
+        caller = f"pkg.views.v{i}.render"
+        _add_fn(old_g, caller, file=f"views/v{i}.js")
+        _add_fn(new_g, caller, file=f"views/v{i}.js")
+        new_g.add_edge(
+            f"node::{caller}", "node::pkg.ui.helpers.formatQn",
+            key="CALLS", kind="CALLS",
+        )
+    diff = diff_graphs(old_g, new_g)
+    findings = evaluate_rules(diff, new_graph=new_g, old_graph=old_g)
+    assert not [f for f in findings if f.rule_id == "new-untested-hotspot"], (
+        "moved symbol must not be reported as a new untested hotspot"
+    )
+
+
+def test_new_untested_hotspot_still_fires_for_genuinely_new() -> None:
+    """Control: a genuinely new high-fan-in untested function still fires."""
+    old_g: nx.MultiDiGraph = nx.MultiDiGraph()
+    new_g: nx.MultiDiGraph = nx.MultiDiGraph()
+    _add_fn(new_g, "pkg.core.hotNew", file="core.py")
+    for i in range(5):
+        caller = f"pkg.views.v{i}.render"
+        _add_fn(old_g, caller, file=f"views/v{i}.py")
+        _add_fn(new_g, caller, file=f"views/v{i}.py")
+        new_g.add_edge(
+            f"node::{caller}", "node::pkg.core.hotNew",
+            key="CALLS", kind="CALLS",
+        )
+    diff = diff_graphs(old_g, new_g)
+    findings = evaluate_rules(diff, new_graph=new_g, old_graph=old_g)
+    assert [f for f in findings if f.rule_id == "new-untested-hotspot"]
+
+
+def test_new_dead_code_skips_moved_symbol() -> None:
+    """A moved symbol with zero callers was already dead before the PR;
+    new-dead-code only reports genuinely new unreachable code."""
+    old_g: nx.MultiDiGraph = nx.MultiDiGraph()
+    new_g: nx.MultiDiGraph = nx.MultiDiGraph()
+    _add_fn(old_g, "pkg.app.orphan", file="app.js")
+    _add_fn(new_g, "pkg.ui.helpers.orphan", file="ui/helpers.js")
+    diff = diff_graphs(old_g, new_g)
+    findings = evaluate_rules(diff, new_graph=new_g, old_graph=old_g)
+    assert not [f for f in findings if f.rule_id == "new-dead-code"]