find-callers misses cross-file callers in .tsx views: exported exportSvg helpers report zero callers

[jpwinans]

Summary

find-callers on the exported helpers in tapestry/src/lib/exportSvg.ts returns empty or intra-file-only caller lists, even though all four Sigma views call them. Cross-file calls edges from the .tsx views are missing from the graph. Intra-file call edges and file-level import edges for the same symbols are correct, so the gap is specific to symbol-level call extraction across files.

Reproduction

Against codebase-the-loom (map commit 0343de0; none of the files below changed between that commit and current HEAD, so this is not map staleness):

loom find-callers '{"name": "exportSvgFile (exportSvg)", "graph": "codebase-the-loom"}'
# → "callers": []

loom find-callers '{"name": "exportPngFile (exportSvg)", "graph": "codebase-the-loom"}'
# → "callers": []

loom find-callers '{"name": "graphToSvg (exportSvg)", "graph": "codebase-the-loom"}'
# → 1 caller: exportSvgFile at tapestry/src/lib/exportSvg.ts:268 (intra-file only)

loom find-callers '{"name": "downloadBlob (exportSvg)", "graph": "codebase-the-loom"}'
# → 2 callers: exportSvg.ts:269, exportSvg.ts:322 (intra-file only)

Actual call sites in the tree:

Symbol	Reported callers	Missing real call sites
exportSvgFile	none	Explorer.tsx:416, Chronicle.tsx:526, SemanticView.tsx:425, SystemsView.tsx:446ff
exportPngFile	none	Explorer.tsx:396, Chronicle.tsx:515, SemanticView.tsx:409, SystemsView.tsx:446
downloadBlob	intra-file ×2	Explorer.tsx:687
exportFilename	intra-file only	Explorer.tsx:398/425/689 + equivalents in the other three views

Each view imports the helpers as destructured named imports, e.g. Explorer.tsx:33:

import { downloadBlob, exportFilename, exportPngFile, exportSvgFile } from "../../lib/exportSvg";

What still works

• Intra-file calls edges in exportSvg.ts resolve (e.g. exportSvgFile → graphToSvg).
• File-level imports are correct: loom explore '{"name": "file:tapestry/src/lib/exportSvg.ts"}' lists all 5 importers (the four views plus the test file).
• blast-radius on the file still reaches the views through file-level requires edges, so file-scoped queries are unaffected.

Possible discriminators

Every missing call site shares three properties, any of which could be the trigger in the tree-sitter call-edge extraction:

1. caller lives in a .tsx file (the resolving intra-file callers are in a .ts file);
2. callee arrives via a destructured named import rather than being defined in-file;
3. the call happens inside a nested arrow function (useCallback body / event handler) inside a React component, so the enclosing symbol attribution may fail. Some sites are additionally void-wrapped (void exportPngFile(...)), but exportSvgFile calls are not and are still missing, so void alone is not the discriminator.

Impact

A zero-callers result reads as "unused, safe to rename or delete" — exactly backwards here. docs/architecture/QUERYING.md steers agents to query the graph before grepping, so this can directly mislead automated consumers into unsafe edits on the frontend helpers.

Workaround

Treat a zero-callers result as inconclusive: corroborate with explore's importedBy list or a direct file read before concluding a symbol is unused.