fix: suppress stdout/stderr leak into TUI by using pipe instead of inherit

[i010542]

Problem

When oh-my-opencode runs as an OpenCode plugin, the plugin is loaded via import() in the same process as the TUI. This means all spawned subprocesses share the same process.stdout and process.stderr file descriptors, which are being used by the TUI's alternate screen mode (@opentui/solid).

Using stdout: "inherit" and stderr: "inherit" in spawnWithWindowsHide() calls causes subprocess output to write directly to the terminal fd, rendering garbage text over the TUI interface.

Symptoms

• bun install output (triggered by auto-update-checker) appears as random text in the TUI
• On-complete hook output leaks into the TUI display
• Users see garbled characters below the status bar

Fix

Changed stdout and stderr from "inherit" to "pipe" in two files:

src/cli/config-manager/bun-install.ts

  const proc = spawnWithWindowsHide(["bun", "install"], {
    cwd: cacheDir,
-   stdout: "inherit",
-   stderr: "inherit",
+   stdout: "pipe",
+   stderr: "pipe",
  })

src/cli/run/on-complete-hook.ts

  const proc = spawnWithWindowsHide(["sh", "-c", trimmedCommand], {
    env: { ... },
-   stdout: "inherit",
-   stderr: "inherit",
+   stdout: "pipe",
+   stderr: "pipe",
  })

Impact

• Subprocess output is silently captured via pipes instead of leaking to the terminal
• The bun install result is already checked via proc.exitCode, so the output is not needed
• The on-complete hook exit code is already checked and logged via console.error
• No functional behavior change — only visual output suppression when running inside a TUI

---

Summary by cubic

Pipe subprocess stdout/stderr to stop output leaking into the TUI’s alternate screen when running as an OpenCode plugin. Prevents bun install and on-complete hook output from rendering over the UI.

• Bug Fixes
  • Changed spawn options from "inherit" to "pipe" in src/cli/config-manager/bun-install.ts and src/cli/run/on-complete-hook.ts to isolate subprocess output.

^{Written for commit 759c900. Summary will update on new commits.}

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[cubic-dev-ai]

2 issues found across 2 files

Confidence score: 2/5

• High-confidence, high-severity findings indicate a real regression risk: both subprocess call sites use "pipe" while discarding output, which can deadlock when buffers fill and cause commands to hang.
• In src/cli/config-manager/bun-install.ts, using "pipe" instead of "ignore" can stall install-related child processes under normal output volume, creating user-facing freezes.
• Pay close attention to src/cli/config-manager/bun-install.ts and src/cli/run/on-complete-hook.ts - both need stdio set to "ignore" (or streams drained) to avoid permanent subprocess hangs.

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/cli/config-manager/bun-install.ts">

<violation number="1" location="src/cli/config-manager/bun-install.ts:34">
P1: Custom agent: **Opencode Compatibility**

Use `"ignore"` instead of `"pipe"` to safely suppress output and prevent the child process from deadlocking when the OS pipe buffer fills up.</violation>
</file>

<file name="src/cli/run/on-complete-hook.ts">

<violation number="1" location="src/cli/run/on-complete-hook.ts:29">
P1: Custom agent: **Opencode Compatibility**

Use `"ignore"` instead of `"pipe"` when discarding subprocess output. Leaving the streams as `"pipe"` without draining them will cause the subprocess to permanently hang if its output exceeds the OS pipe buffer size.</violation>
</file>

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[cubic-dev-ai]

P1: Custom agent: Opencode Compatibility

Use "ignore" instead of "pipe" to safely suppress output and prevent the child process from deadlocking when the OS pipe buffer fills up.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/cli/config-manager/bun-install.ts, line 34:

<comment>Use `"ignore"` instead of `"pipe"` to safely suppress output and prevent the child process from deadlocking when the OS pipe buffer fills up.</comment>

<file context>
@@ -31,8 +31,8 @@ export async function runBunInstallWithDetails(): Promise<BunInstallResult> {
       cwd: cacheDir,
-      stdout: "inherit",
-      stderr: "inherit",
+      stdout: "pipe",
+      stderr: "pipe",
     })
</file context>

[cubic-dev-ai]

P1: Custom agent: Opencode Compatibility

Use "ignore" instead of "pipe" when discarding subprocess output. Leaving the streams as "pipe" without draining them will cause the subprocess to permanently hang if its output exceeds the OS pipe buffer size.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/cli/run/on-complete-hook.ts, line 29:

<comment>Use `"ignore"` instead of `"pipe"` when discarding subprocess output. Leaving the streams as `"pipe"` without draining them will cause the subprocess to permanently hang if its output exceeds the OS pipe buffer size.</comment>

<file context>
@@ -26,8 +26,8 @@ export async function executeOnCompleteHook(options: {
       },
-      stdout: "inherit",
-      stderr: "inherit",
+      stdout: "pipe",
+      stderr: "pipe",
     })
</file context>

Suggested change

	stdout: "pipe",
	stderr: "pipe",
	stdout: "ignore",
	stderr: "ignore",