Fix persistent FAT32 format failure: single-pass diskpart script (v3.2.2)

Fixes #49 — FAT32 format still failing on v3.2.0 despite automount disable

Root cause: The v3.1.9 automount fix used two separate diskpart processes
(Phase 1: create partition, Phase 2: format). automount disable only persists
within the diskpart session on some Windows 10 builds. Between Phase 1 exiting
and Phase 2 launching (~1.5s gap), Explorer re-acquired a handle on the raw
partition, causing the format to fail even with automount disabled.

Fix: Merged Phase 1 and Phase 2 into a single diskpart script that runs
clean → convert gpt → create partition → format fs=fat32 → assign in ONE
diskpart session. This eliminates the inter-process window entirely.

The single-pass script uses noerr on safe preliminary commands (clean, convert,
create) but NOT on the format command so failures still surface immediately
(preserving #38/#41 fix). Phase 2 remains as a fallback only if the single-pass
format step fails for other reasons (e.g. drive controller issue).

Author: redpersongpt

electron/diskOps.ts

@@ -232,11 +232,12 @@ export function isWindowsUsbLikeDisk(input: {
 }
 
 export function buildWindowsFlashDiskpartScript(diskNum: string, partitionSizeMB?: number): string {
+  // Single-pass diskpart script: clean → create → format → assign in ONE session.
+  // Previous design used two separate diskpart invocations (Phase 1: create, Phase 2: format).
+  // This caused persistent FAT32 format failures (#48, #49) because Explorer/Shell auto-mounts
+  // the raw partition in the gap between the two processes, locking it before format can run.
+  // Merging into one session eliminates the inter-process window entirely.
   return [
-    // Disable automount BEFORE creating the partition to prevent Explorer
-    // from immediately grabbing a handle on the new raw volume.
-    // This is the root cause of FAT32 format failures (#48): Explorer
-    // auto-mounts the partition between create and format, locking it.
     'automount disable',
     `select disk ${diskNum}`,
     'attributes disk clear readonly noerr',
@@ -247,6 +248,11 @@ export function buildWindowsFlashDiskpartScript(diskNum: string, partitionSizeMB
     partitionSizeMB && partitionSizeMB > 0
       ? `create partition primary size=${partitionSizeMB} noerr`
       : 'create partition primary noerr',
+    // Format WITHOUT noerr so failures surface immediately (#38, #41).
+    // Running in the same session as create eliminates the Explorer lock race (#48, #49).
+    'format fs=fat32 quick label=OPENCORE',
+    'assign noerr',
+    'automount enable',
     'rescan',
     '',
   ].join('\n');

package.json

@@ -1,7 +1,7 @@
 {
   "name": "opcore-oneclick",
   "private": true,
-  "version": "3.2.1",
+  "version": "3.2.2",
   "description": "OpCore-OneClick deployment utility",
   "author": "OpCore-OneClick contributors",
   "main": "dist-electron/electron/main.js",

test/diskOps.test.ts

@@ -170,10 +170,10 @@ describe('buildWindowsFlashDiskpartScript', () => {
     expect(script).toContain('convert gpt noerr');
   });
 
-  it('does NOT contain format or assign (moved to phase 2)', () => {
+  it('contains format and assign in single-pass script (#48, #49)', () => {
     const script = buildWindowsFlashDiskpartScript('0');
-    expect(script).not.toContain('format fs=fat32');
-    expect(script).not.toContain('assign noerr');
+    expect(script).toContain('format fs=fat32 quick label=OPENCORE');
+    expect(script).toContain('assign noerr');
   });
 });
 
@@ -220,9 +220,9 @@ describe('buildWindowsConvertToGptDiskpartScript', () => {
     expect(script).toContain('rescan');
   });
 
-  it('does NOT contain format (moved to phase 2 script)', () => {
+  it('contains format in single-pass script (#48, #49)', () => {
     const script = buildWindowsConvertToGptDiskpartScript('2');
-    expect(script).not.toContain('format fs=fat32');
+    expect(script).toContain('format fs=fat32 quick label=OPENCORE');
   });
 
   it('uses the Windows FAT32 size cap when provided', () => {