Stage tree-sitter.wasm into pre-init/ for relative with { type: 'file' }

On Windows, bun --compile bundles the wasm bytes (build verification
finds them at a known offset) but the JS-level binding from a
node_modules subpath import returns falsy at runtime:

    import wasmPath from 'web-tree-sitter/tree-sitter.wasm'
      with { type: 'file' }
    // wasmPath is undefined on Windows even though the bytes are in
    // the binary

Smoke check on the failed release confirmed it directly:

    tree-sitter smoke FAIL: pre-init published neither globalThis bytes
    nor an env path. The `with { type: 'file' }` import returned falsy.

OpenTUI's own tree-sitter assets work because they're imported via
*relative* paths from inside the package. Mirror that: copy the wasm
into cli/src/pre-init/ before `bun build --compile`, import it
relatively, remove the copy after the build.

- cli/scripts/build-binary.ts: stagePreInitWasm() copies the source
  wasm to cli/src/pre-init/tree-sitter.wasm; cleanup runs after the
  compile and is also wired to process.on('exit') so a build-script
  crash doesn't leave a multi-MB untracked file in the working tree.
  The findWebTreeSitterWasm() lookup is shared with the post-build
  verification.
- cli/src/pre-init/tree-sitter-wasm.ts: import is now `./tree-sitter.wasm`
  (relative). The file is .gitignored so dev-mode runs see no wasm here
  and fall through to init-node.ts's path-based resolution, which
  works locally because node_modules has the file.
- cli/.gitignore: ignore the staged copy.

Verified locally: build stages then cleans up the wasm,
post-build verification finds the bytes, --smoke-tree-sitter exits 0
with "tree-sitter smoke ok (wasmBinary, 205488 bytes)".

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: jahooma

cli/.gitignore

@@ -7,3 +7,7 @@ debug/
 
 # Generated files
 src/agents/bundled-agents.generated.ts
+
+# Staged by build-binary.ts before `bun build --compile`, removed after.
+# See cli/src/pre-init/tree-sitter-wasm.ts for why we copy this in.
+src/pre-init/tree-sitter.wasm

cli/scripts/build-binary.ts

@@ -145,6 +145,10 @@ async function main() {
   patchOpenTuiAssetPaths()
   await ensureOpenTuiNativeBundle(targetInfo)
 
+  const wasmCopy = stagePreInitWasm()
+  // Even on a build-script crash, leave the developer's working tree clean.
+  process.on('exit', wasmCopy.cleanup)
+
   const outputFilename =
     targetInfo.platform === 'win32' ? `${binaryName}.exe` : binaryName
   const outputFile = join(binDir, outputFilename)
@@ -186,6 +190,11 @@ async function main() {
 
   runCommand('bun', buildArgs, { cwd: cliRoot })
 
+  // Remove the staged pre-init wasm now that the build has read it. Eager
+  // cleanup keeps a successful build clean; the exit handler above is a
+  // backstop for crashes between stage and now.
+  wasmCopy.cleanup()
+
   // Fail the build if the wasm asset didn't actually make it into the
   // compiled binary. The pre-init imports tree-sitter.wasm with `with {
   // type: 'file' }`, which Bun should embed; this scan catches silent
@@ -211,6 +220,70 @@ main().catch((error: unknown) => {
   process.exit(1)
 })
 
+/**
+ * Find web-tree-sitter's tree-sitter.wasm in any plausible node_modules
+ * layout — bun hoists differently across platforms and `bun install`
+ * variants, and CI Windows lays it out differently than monorepo-root
+ * installs.
+ */
+function findWebTreeSitterWasm(): string {
+  const candidates = [
+    join(cliRoot, 'node_modules', 'web-tree-sitter', 'tree-sitter.wasm'),
+    join(cliRoot, '..', 'node_modules', 'web-tree-sitter', 'tree-sitter.wasm'),
+    join(cliRoot, '..', 'sdk', 'node_modules', 'web-tree-sitter', 'tree-sitter.wasm'),
+  ]
+  const found = candidates.find((p) => existsSync(p))
+  if (found) return found
+  try {
+    const cliRequire = createRequire(join(cliRoot, 'package.json'))
+    return cliRequire.resolve('web-tree-sitter/tree-sitter.wasm')
+  } catch (err) {
+    throw new Error(
+      `Could not locate web-tree-sitter/tree-sitter.wasm. Searched:\n  - ` +
+        candidates.join('\n  - ') +
+        `\nAnd createRequire failed: ${err instanceof Error ? err.message : String(err)}`,
+    )
+  }
+}
+
+/**
+ * Copy `tree-sitter.wasm` into `cli/src/pre-init/` so the pre-init module
+ * can import it via a relative `with { type: 'file' }` path. We can't
+ * import it directly as a node_modules subpath: on Windows, bun's
+ * `with { type: 'file' }` resolution returned falsy at runtime for
+ * `web-tree-sitter/tree-sitter.wasm` even though the bytes ended up in
+ * the binary, breaking the pre-init's runtime path lookup. OpenTUI's own
+ * tree-sitter assets work because they're imported relatively from
+ * inside the package — same trick here.
+ *
+ * Returns a cleanup function. The build calls it eagerly after compile
+ * and registers it as an exit handler so a mid-build crash doesn't leave
+ * a multi-MB untracked file in the working tree.
+ */
+function stagePreInitWasm(): { cleanup: () => void } {
+  const sourceWasm = findWebTreeSitterWasm()
+  const stagedPath = join(cliRoot, 'src', 'pre-init', 'tree-sitter.wasm')
+  let cleaned = false
+  const cleanup = (): void => {
+    if (cleaned) return
+    cleaned = true
+    if (existsSync(stagedPath)) {
+      try {
+        rmSync(stagedPath)
+      } catch (error) {
+        console.error('Failed to remove staged pre-init wasm:', error)
+      }
+    }
+  }
+
+  // Read + write rather than copyFile so we don't accidentally hardlink
+  // (some Windows hosts fail to delete hardlinks while bun has the file
+  // mmapped from the compile step).
+  writeFileSync(stagedPath, readFileSync(sourceWasm))
+  logAlways(`Staged pre-init wasm: ${sourceWasm} → ${stagedPath}`)
+  return { cleanup }
+}
+
 /**
  * Sanity-check the compiled binary actually contains web-tree-sitter's
  * tree-sitter.wasm. The pre-init imports it via `with { type: 'file' }`,
@@ -226,25 +299,7 @@ main().catch((error: unknown) => {
  * proves *this specific* wasm shipped.
  */
 function verifyTreeSitterWasmEmbedded(outputFile: string): void {
-  const candidates = [
-    join(cliRoot, 'node_modules', 'web-tree-sitter', 'tree-sitter.wasm'),
-    join(cliRoot, '..', 'node_modules', 'web-tree-sitter', 'tree-sitter.wasm'),
-    join(cliRoot, '..', 'sdk', 'node_modules', 'web-tree-sitter', 'tree-sitter.wasm'),
-  ]
-  let wasmPath = candidates.find((p) => existsSync(p))
-  if (!wasmPath) {
-    try {
-      const cliRequire = createRequire(join(cliRoot, 'package.json'))
-      wasmPath = cliRequire.resolve('web-tree-sitter/tree-sitter.wasm')
-    } catch (err) {
-      throw new Error(
-        `Could not locate web-tree-sitter/tree-sitter.wasm to verify against. Searched:\n  - ` +
-          candidates.join('\n  - ') +
-          `\nAnd createRequire failed: ${err instanceof Error ? err.message : String(err)}`,
-      )
-    }
-  }
-
+  const wasmPath = findWebTreeSitterWasm()
   const wasm = readFileSync(wasmPath)
   // Take a 64-byte slice from the middle of the file. The header has
   // generic wasm magic + section markers; the tail can be padding. The

cli/src/pre-init/tree-sitter-wasm.ts

@@ -13,11 +13,22 @@
 
 import { readFileSync } from 'fs'
 
-// @ts-expect-error - Bun's `with { type: 'file' }` returns a string path; TS
-// has no loader for the .wasm subpath of web-tree-sitter's package exports.
-import treeSitterWasmPath from 'web-tree-sitter/tree-sitter.wasm' with {
-  type: 'file',
-}
+// Important: this is a *relative* import of a wasm file the build script
+// copies in from `web-tree-sitter/tree-sitter.wasm` immediately before
+// `bun build --compile`. On Windows, bun's `with { type: 'file' }`
+// returned falsy at runtime when this import was a node_modules subpath
+// (`web-tree-sitter/tree-sitter.wasm`) even though the bytes ended up in
+// the binary — OpenTUI works around the same issue by using relative
+// paths from inside its own package, which is what we're mirroring here.
+//
+// The `.wasm` lives at `./tree-sitter.wasm` next to this file. It is
+// .gitignored; build-binary.ts copies it in before compile and removes
+// it after, so dev-mode runs see no `.wasm` here and fall back to
+// path-based resolution via init-node.ts (which works locally).
+//
+// @ts-expect-error - TS has no loader for .wasm; bun's `with { type: 'file' }`
+// returns a string path at compile time.
+import treeSitterWasmPath from './tree-sitter.wasm' with { type: 'file' }
 
 let embeddedWasm: Uint8Array | undefined