scrubSecrets() throws "result.replace is not a function" on non-string input → recurring plugin-load failure

[JRedeker]

Summary

scrubSecrets() throws result.replace is not a function when message is not a string at runtime. This surfaces to OpenCode as a recurring "failed to load plugin" error, which disables the morph_edit tool for the affected session and spams the OpenCode log.

Symptom (from OpenCode host log)

Observed repeatedly across many sessions/days:

level=ERROR message="failed to load plugin"
  path=file:///.../node_modules/opencode-morph-fast-apply/index.ts
  error="result.replace is not a function.
  (In 'result.replace(/Bearer\s+[A-Za-z0-9_\-\.]{10,}/gi, \"Bearer ***REDACTED***\")',
  'result.replace' is undefined)"

The unique regex pins the throw site to index.ts:

// index.ts  (v1.10.0)
export function scrubSecrets(message: string, apiKey?: string): string {
  let result = message;
  if (apiKey) {
    result = result.split(apiKey).join("***REDACTED***");   // also throws on non-string
  }
  result = result.replace(                                    // <-- throws here
    /Bearer\s+[A-Za-z0-9_\-\.]{10,}/gi,
    "Bearer ***REDACTED***",
  );
  return result;
}

Root cause

scrubSecrets is typed (message: string, ...) but is not defensive at runtime. When a caller passes a non-string (e.g. an Error object, undefined, or a number from an error/exception path), result.replace / result.split are undefined and throw. The TS type does not protect against this because the offending value originates from a catch/error path that escapes static typing.

In-repo callers:

• index.ts:124 — scrubSecrets(\Morph API error (${response.status}): ${errorText}`, apiKey)`
• index.ts:184 — scrubSecrets(\Morph API request failed: ${error.message}`, apiKey)`
• src/execute.ts:175 — scrubSecrets(result.error || "unknown error", MORPH_API_KEY)

These pass strings in the happy path, but the runtime error proves at least one path delivers a non-string message (or a non-string apiKey reaching split). The function should never throw while scrubbing an error message — failing to scrub turns a recoverable error into a plugin-load failure.

Proposed fix

Harden scrubSecrets to coerce input and never throw:

export function scrubSecrets(message: unknown, apiKey?: unknown): string {
  let result =
    typeof message === "string"
      ? message
      : message instanceof Error
        ? message.message
        : String(message ?? "");
  if (typeof apiKey === "string" && apiKey.length > 0) {
    result = result.split(apiKey).join("***REDACTED***");
  }
  result = result.replace(
    /Bearer\s+[A-Za-z0-9_\-\.]{10,}/gi,
    "Bearer ***REDACTED***",
  );
  return result;
}

Optionally also audit callers to pass err instanceof Error ? err.message : String(err) rather than raw error objects.

A regression test should cover: Error instance, undefined, null, number, and a string containing a Bearer token + the API key.

Impact

• Severity: medium. No data loss; the plugin simply fails to load, so morph_edit is unavailable and agents fall back to native edit tools. Log noise on every (re)load.
• Not a crash cause: filing this separately from an unrelated OpenCode/Bun host crash investigated at the same time — this defect does not segfault the host, it only fails plugin load.

Environment

• opencode-morph-fast-apply v1.10.0 (installed)
• OpenCode 1.17.11
• Runtime: Bun (OpenCode host)
• OS: Linux (WSL2, 6.6.114.1-microsoft-standard-WSL2)

If this is already fixed on main/a newer published version, please disregard — installed copy is 1.10.0.