fix #432 to_html crash on large graphs, fix #431 Go import node ID collision

CHANGELOG.md

@@ -6,6 +6,8 @@ Full release notes with details on each version: [GitHub Releases](https://githu
 
 - Fix: stale skill version warning persists after running `graphify install` when multiple platforms were previously installed — `graphify install` now refreshes `.graphify_version` in all other known skill directories so the warning clears across the board (#178)
 - Fix: `.html` files silently skipped during detection — added `.html` to `DOC_EXTENSIONS`; HTML pages, docs, and web project content now indexed correctly (#260)
+- Fix: `_rebuild_code` (watch/update/hook) fails entirely on graphs > 5000 nodes because `to_html` raises `ValueError` — wrapped in its own try/except so `graph.json` and `GRAPH_REPORT.md` always land; stale `graph.html` from a previous smaller run is removed (#432)
+- Fix: Go stdlib imports (e.g. `"context"`) produced `imports_from` edges pointing at local files of the same basename — Go import node IDs now prefixed `go_pkg_` using the full import path, eliminating false cycle-dependency pairs (#431)
 
 ## 0.4.22 (2026-04-18)
 

graphify/extract.py

@@ -1947,15 +1947,15 @@ def extract_go(path: Path) -> dict:
                             path_node = spec.child_by_field_name("path")
                             if path_node:
                                 raw = _read_text(path_node, source).strip('"')
-                                module_name = raw.split("/")[-1]
-                                tgt_nid = _make_id(module_name)
+                                # Prefix with go_pkg_ so stdlib names (e.g. "context")
+                                # don't collide with local files of the same basename.
+                                tgt_nid = _make_id("go", "pkg", raw)
                                 add_edge(file_nid, tgt_nid, "imports_from", spec.start_point[0] + 1)
                 elif child.type == "import_spec":
                     path_node = child.child_by_field_name("path")
                     if path_node:
                         raw = _read_text(path_node, source).strip('"')
-                        module_name = raw.split("/")[-1]
-                        tgt_nid = _make_id(module_name)
+                        tgt_nid = _make_id("go", "pkg", raw)
                         add_edge(file_nid, tgt_nid, "imports_from", child.start_point[0] + 1)
             return
 

graphify/watch.py

@@ -78,7 +78,18 @@ def _rebuild_code(watch_path: Path, *, follow_symlinks: bool = False) -> bool:
                           {"input": 0, "output": 0}, str(watch_path), suggested_questions=questions)
         (out / "GRAPH_REPORT.md").write_text(report, encoding="utf-8")
         to_json(G, communities, str(out / "graph.json"))
+
+        # to_html raises ValueError for graphs > MAX_NODES_FOR_VIZ (5000).
+        # Wrap so core outputs (graph.json + GRAPH_REPORT.md) always land.
+        html_written = False
+        try:
             to_html(G, communities, str(out / "graph.html"), community_labels=labels or None)
+            html_written = True
+        except ValueError as viz_err:
+            print(f"[graphify watch] Skipped graph.html: {viz_err}")
+            stale = out / "graph.html"
+            if stale.exists():
+                stale.unlink()
 
         # clear stale needs_update flag if present
         flag = out / "needs_update"
@@ -87,7 +98,8 @@ def _rebuild_code(watch_path: Path, *, follow_symlinks: bool = False) -> bool:
 
         print(f"[graphify watch] Rebuilt: {G.number_of_nodes()} nodes, "
               f"{G.number_of_edges()} edges, {len(communities)} communities")
-        print(f"[graphify watch] graph.json, graph.html and GRAPH_REPORT.md updated in {out}")
+        products = "graph.json" + (", graph.html" if html_written else "") + " and GRAPH_REPORT.md"
+        print(f"[graphify watch] {products} updated in {out}")
         return True
 
     except Exception as exc: