From 08ba7101acb1f341e0fb98a578eb323e8b1ac44b Mon Sep 17 00:00:00 2001
From: Aleksandar Grbic <ag@dreamdata.io>
Date: Thu, 16 Jul 2026 19:10:22 +0200
Subject: [PATCH] fix(script-tool): force color off in captured script output
 (deterministic)
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The script tool's subprocess stdout is CAPTURED — parsed by the loop and matched in
tests — never shown live in a terminal, so ANSI colorization is corruption, not
presentation. Bun colorizes console.log values (a numeric `403` becomes
\x1b[33m403\x1b[0m) whenever it detects color support, so captured output differed
between CI (no TTY, plain) and a local TTY (colored): script-tool's wrong-token test
asserts a literal 'STATUS 403' and passed in CI but broke under the local pre-push
hook. Set NO_COLOR=1 / FORCE_COLOR=0 in the script subprocess env so captured output
is plain and stable everywhere.
---
 packages/core/src/loop/tools/script-tool.ts |  9 ++++
 packages/core/tests/script-tool.test.ts     | 47 +++++++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/packages/core/src/loop/tools/script-tool.ts b/packages/core/src/loop/tools/script-tool.ts
index 8f0ea5e9..9be841fc 100644
--- a/packages/core/src/loop/tools/script-tool.ts
+++ b/packages/core/src/loop/tools/script-tool.ts
@@ -313,6 +313,15 @@ export async function doScript(
       ctx.cwd,
       {
         ...process.env,
+        // The script's stdout is CAPTURED (parsed by the loop, matched in tests),
+        // never shown live in a terminal — so any ANSI colorization is corruption,
+        // not presentation. Bun colorizes console.log values (e.g. a numeric
+        // `403` → `\x1b[33m403\x1b[0m`) whenever it detects color support, which
+        // makes captured output non-deterministic across TTY/no-TTY (a literal
+        // "STATUS 403" match passes in CI but breaks under the local pre-push).
+        // Force color OFF so captured output is plain and stable everywhere.
+        NO_COLOR: "1",
+        FORCE_COLOR: "0",
         TSFORGE_RPC_URL: server.url,
         TSFORGE_RPC_TOKEN: server.token,
       },
diff --git a/packages/core/tests/script-tool.test.ts b/packages/core/tests/script-tool.test.ts
index 07f66ed0..e355134e 100644
--- a/packages/core/tests/script-tool.test.ts
+++ b/packages/core/tests/script-tool.test.ts
@@ -435,6 +435,24 @@ test("the RPC server rejects a request with a wrong token", async () => {
   expect(calls).toHaveLength(0);
 });
 
+test("captured script output is PLAIN — no ANSI color on logged values", async () => {
+  // The script's stdout is captured (parsed by the loop, matched in tests), never
+  // shown live — so Bun's console.log colorization (a number `403` →
+  // `\x1b[33m403\x1b[0m` under a TTY) is corruption that made captured output
+  // differ CI-vs-local. runScript sets NO_COLOR/FORCE_COLOR so output is stable;
+  // this locks that in — a regression re-enabling color would fail here.
+  const events: ILoopEvent[] = [];
+  const code = 'console.log("VAL", 403, true, { a: 1 });';
+  const out = await doScript({ code }, makeCtx({}, events), {
+    execute: recordingExecute([]),
+  });
+
+  // No ANSI escape sequence anywhere in the captured output.
+  expect(out).not.toContain("[");
+  // And the plain values survive verbatim (proves it's off, not stripped-after).
+  expect(out).toContain("VAL 403 true");
+});
+
 test("the RPC server refuses `script` (no recursion) and non-exposable tools", async () => {
   const events: ILoopEvent[] = [];
   const code = [
@@ -498,3 +516,32 @@ test("empty `code` is rejected without spawning anything", async () => {
   expect(out).toContain("must be a non-empty");
   expect(calls).toHaveLength(0);
 });
+
+test("captured script output is ANSI-free even when the parent env forces color", async () => {
+  // The subprocess stdout is CAPTURED (parsed by the loop, matched in tests),
+  // never shown live — so Bun colorizing a console.log'd value (a numeric 403 →
+  // \x1b[33m403\x1b[0m under a color-enabled parent) is corruption that made
+  // captured output differ between CI (plain) and a local TTY (colored). The tool
+  // sets NO_COLOR/FORCE_COLOR=0 in the child env; the captured text must be plain.
+  const events: ILoopEvent[] = [];
+  const savedForce = process.env.FORCE_COLOR;
+
+  process.env.FORCE_COLOR = "1"; // simulate a color-enabled parent (local TTY)
+
+  try {
+    const out = await doScript(
+      { code: "console.log(403);" },
+      makeCtx({}, events),
+      { execute: recordingExecute([]) }
+    );
+
+    expect(out).not.toMatch(new RegExp(String.fromCharCode(27)));
+    expect(out).toContain("403");
+  } finally {
+    if (savedForce === undefined) {
+      Reflect.deleteProperty(process.env, "FORCE_COLOR");
+    } else {
+      process.env.FORCE_COLOR = savedForce;
+    }
+  }
+});