fix(pty): graceful degradation when bun-pty native library unavailable

[vtemian]

Summary

• Auto-resolve BUN_PTY_LIB by probing .opencode/node_modules/ and other paths that bun-pty's resolveLibPath() misses
• Load bun-pty dynamically so the plugin still loads (without PTY tools) when the native library can't be found
• Log actionable warnings when PTY is unavailable instead of crashing

Fixes #20

Problem

When micode is installed as an OpenCode plugin, bun-pty's native library (librust_pty.so/.dylib) ends up in .opencode/node_modules/bun-pty/... — a path not in bun-pty's hardcoded search list. This causes the plugin to crash on startup.

Root cause is upstream: anomalyco/opencode#10556

Changes

New: src/tools/pty/pty-loader.ts

• Probes additional paths (.opencode/node_modules/, .micode/node_modules/, require.resolve) and sets BUN_PTY_LIB env var before import
• Wraps import("bun-pty") in try/catch for graceful degradation
• Caches result so probing only happens once

Modified: src/tools/pty/manager.ts

• Removed static import { spawn } from "bun-pty" (would crash at module load)
• Added init(spawnFn) — spawn function is injected after successful loading
• Added available getter for callers to check PTY status

Modified: src/index.ts

• Uses loadBunPty() to dynamically load with path probing
• Conditionally registers PTY tools only if bun-pty loaded successfully

Tests

• All 6 PTY test files updated to use manager.init(spawn) pattern
• 60/60 PTY tests pass, full suite 364/365 (1 pre-existing failure unrelated)

Manual workaround

If auto-resolution doesn't cover a specific setup:

export BUN_PTY_LIB=.opencode/node_modules/bun-pty/rust-pty/target/release/librust_pty.dylib

[cubic-dev-ai]

1 issue found across 11 files

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/tools/pty/pty-loader.ts">

<violation number="1" location="src/tools/pty/pty-loader.ts:90">
P2: `loadBunPty()` has a concurrency race: concurrent callers can get `null` while the first import is still in flight. Cache and return the in-flight Promise instead of returning `cachedModule` immediately once `loadAttempted` is set.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: loadBunPty() has a concurrency race: concurrent callers can get null while the first import is still in flight. Cache and return the in-flight Promise instead of returning cachedModule immediately once loadAttempted is set.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/tools/pty/pty-loader.ts, line 90:

<comment>`loadBunPty()` has a concurrency race: concurrent callers can get `null` while the first import is still in flight. Cache and return the in-flight Promise instead of returning `cachedModule` immediately once `loadAttempted` is set.</comment>

<file context>
@@ -0,0 +1,123 @@
+ * Returns null if bun-pty cannot be loaded (native library missing, etc.)
+ */
+export async function loadBunPty(): Promise<BunPtyModule | null> {
+  if (loadAttempted) return cachedModule;
+  loadAttempted = true;
+
</file context>