From 7a4b401520c53fb201cf3b3844f6a0a456b94452 Mon Sep 17 00:00:00 2001
From: Bikash Joshi <bkashjee@gmail.com>
Date: Mon, 20 Apr 2026 01:21:43 -0700
Subject: [PATCH] fix(make-pdf): resolveBrowseBin() now works on Windows
 without BROWSE_BIN
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The binary resolution chain in `make-pdf/src/browseClient.ts` hardcoded
the Unix binary name `browse` and the Unix lookup tool `which`. On Windows
the compiled binary is `browse.exe`, so every fallback (sibling paths,
global install at `~/.claude/skills/gstack/browse/dist/browse`, PATH
lookup) missed, and users hit a cryptic "browse binary not found" error
unless they knew to set `BROWSE_BIN` manually.

Changes:
- Branch binary name on `process.platform === "win32"` → append `.exe`.
- Use `where` on Windows, `which` on Unix; parse first line of `where`
  output (can be multi-line across PATHEXT hits).
- `isExecutable()` checks `F_OK` on Windows because NTFS has no execute
  bit and `X_OK` is unreliable (Node delegates to `AccessCheck` which
  can false-negative on .exe files depending on ACLs).
- Error message now shows the actual binary name being searched and
  suggests `setx BROWSE_BIN ...` on Windows instead of `export`.

Verified on Windows 11 + Git Bash:
- Before patch: `pdf.exe generate ...` fails with "browse binary not
  found" unless `BROWSE_BIN` is set explicitly via `setx`.
- After patch: succeeds with empty `BROWSE_BIN`, finds
  `~/.claude/skills/gstack/browse/dist/browse.exe` via the global path
  branch. Rendered a 51KB smoke-test PDF end-to-end.

No behavior change on macOS/Linux (suffix is empty string, lookup tool
stays `which`, permission check stays `X_OK`).
---
 make-pdf/src/browseClient.ts | 37 +++++++++++++++++++++++++-----------
 1 file changed, 26 insertions(+), 11 deletions(-)

diff --git a/make-pdf/src/browseClient.ts b/make-pdf/src/browseClient.ts
index 9284590731..75bbcc79d0 100644
--- a/make-pdf/src/browseClient.ts
+++ b/make-pdf/src/browseClient.ts
@@ -62,13 +62,17 @@ export function resolveBrowseBin(): string {
   const envOverride = process.env.BROWSE_BIN;
   if (envOverride && isExecutable(envOverride)) return envOverride;
 
+  const isWin = process.platform === "win32";
+  const exeSuffix = isWin ? ".exe" : "";
+  const binName = `browse${exeSuffix}`;
+
   // Sibling: look relative to this process's binary
   // (for when make-pdf and browse live next to each other in dist/)
   const selfDir = path.dirname(process.argv[0]);
   const siblingCandidates = [
-    path.resolve(selfDir, "../browse/dist/browse"),
-    path.resolve(selfDir, "../../browse/dist/browse"),
-    path.resolve(selfDir, "../browse"),
+    path.resolve(selfDir, `../browse/dist/${binName}`),
+    path.resolve(selfDir, `../../browse/dist/${binName}`),
+    path.resolve(selfDir, `../${binName}`),
   ];
   for (const candidate of siblingCandidates) {
     if (isExecutable(candidate)) return candidate;
@@ -76,15 +80,18 @@ export function resolveBrowseBin(): string {
 
   // Global install
   const home = os.homedir();
-  const globalPath = path.join(home, ".claude/skills/gstack/browse/dist/browse");
+  const globalPath = path.join(home, ".claude/skills/gstack/browse/dist", binName);
   if (isExecutable(globalPath)) return globalPath;
 
-  // PATH lookup
+  // PATH lookup — Windows uses `where`, Unix uses `which`
+  const lookupCmd = isWin ? "where" : "which";
   try {
-    const which = execFileSync("which", ["browse"], { encoding: "utf8" }).trim();
-    if (which && isExecutable(which)) return which;
+    const out = execFileSync(lookupCmd, [binName], { encoding: "utf8" }).trim();
+    // `where` can return multiple lines; take first
+    const first = out.split(/\r?\n/)[0]?.trim();
+    if (first && isExecutable(first)) return first;
   } catch {
-    // `which` exited non-zero; fall through to error
+    // lookup exited non-zero; fall through to error
   }
 
   throw new BrowseClientError(
@@ -94,24 +101,32 @@ export function resolveBrowseBin(): string {
       "browse binary not found.",
       "",
       "make-pdf needs browse (the gstack Chromium daemon) to render PDFs.",
+      `Platform: ${process.platform} (looking for "${binName}")`,
       "Tried:",
       `  - $BROWSE_BIN (${envOverride || "unset"})`,
       `  - sibling: ${siblingCandidates.join(", ")}`,
       `  - global: ${globalPath}`,
-      "  - PATH: `browse`",
+      `  - PATH: \`${lookupCmd} ${binName}\``,
       "",
       "To fix: run gstack setup from the gstack repo:",
       "  cd ~/.claude/skills/gstack && ./setup",
       "",
       "Or set BROWSE_BIN explicitly:",
-      "  export BROWSE_BIN=/path/to/browse",
+      isWin
+        ? '  setx BROWSE_BIN "C:\\path\\to\\browse.exe"'
+        : "  export BROWSE_BIN=/path/to/browse",
     ].join("\n"),
   );
 }
 
 function isExecutable(p: string): boolean {
   try {
-    fs.accessSync(p, fs.constants.X_OK);
+    // Windows: NTFS has no execute bit. X_OK is unreliable — use F_OK
+    // (file exists) and let the OS decide at execFile time.
+    const mode = process.platform === "win32"
+      ? fs.constants.F_OK
+      : fs.constants.X_OK;
+    fs.accessSync(p, mode);
     return true;
   } catch {
     return false;