fix(windows): handle full paths in known exe command detection

Fixes an issue in PR #288's Windows shell fix where full paths like
'C:\Program Files\Git\bin\git' weren't recognized as known commands.

Changes:
- Extract command basename using regex for both Unix and Windows separators
- Change from array to Set for O(1) lookup performance
- Add additional common commands: npx, pnpm, pip, pip3
- Export needsWindowsShell for testability
- Add comprehensive test suite for needsWindowsShell function

src/__tests__/main/utils/needsWindowsShell.test.ts

@@ -0,0 +1,84 @@
+/**
+ * Tests for needsWindowsShell function in src/main/utils/execFile.ts
+ *
+ * This function determines whether a command needs shell execution on Windows.
+ * Separated into its own test file to avoid module mocking conflicts.
+ */
+
+import { describe, it, expect } from 'vitest';
+import { needsWindowsShell } from '../../../main/utils/execFile';
+
+describe('needsWindowsShell', () => {
+	describe('batch files', () => {
+		it('should return true for .cmd files', () => {
+			expect(needsWindowsShell('setup.cmd')).toBe(true);
+			expect(needsWindowsShell('C:\\path\\to\\setup.CMD')).toBe(true);
+		});
+
+		it('should return true for .bat files', () => {
+			expect(needsWindowsShell('install.bat')).toBe(true);
+			expect(needsWindowsShell('C:\\path\\to\\INSTALL.BAT')).toBe(true);
+		});
+	});
+
+	describe('executables', () => {
+		it('should return false for .exe files', () => {
+			expect(needsWindowsShell('program.exe')).toBe(false);
+			expect(needsWindowsShell('C:\\path\\to\\program.EXE')).toBe(false);
+		});
+
+		it('should return false for .com files', () => {
+			expect(needsWindowsShell('command.com')).toBe(false);
+			expect(needsWindowsShell('C:\\path\\to\\COMMAND.COM')).toBe(false);
+		});
+	});
+
+	describe('known commands with .exe variants', () => {
+		it('should return false for git', () => {
+			expect(needsWindowsShell('git')).toBe(false);
+			expect(needsWindowsShell('GIT')).toBe(false);
+		});
+
+		it('should return false for git with full path', () => {
+			expect(needsWindowsShell('C:\\Program Files\\Git\\bin\\git')).toBe(false);
+			expect(needsWindowsShell('/usr/bin/git')).toBe(false);
+		});
+
+		it('should return false for node', () => {
+			expect(needsWindowsShell('node')).toBe(false);
+			expect(needsWindowsShell('C:\\nodejs\\node')).toBe(false);
+		});
+
+		it('should return false for npm/npx/yarn/pnpm', () => {
+			expect(needsWindowsShell('npm')).toBe(false);
+			expect(needsWindowsShell('npx')).toBe(false);
+			expect(needsWindowsShell('yarn')).toBe(false);
+			expect(needsWindowsShell('pnpm')).toBe(false);
+		});
+
+		it('should return false for python/python3', () => {
+			expect(needsWindowsShell('python')).toBe(false);
+			expect(needsWindowsShell('python3')).toBe(false);
+		});
+
+		it('should return false for pip/pip3', () => {
+			expect(needsWindowsShell('pip')).toBe(false);
+			expect(needsWindowsShell('pip3')).toBe(false);
+		});
+	});
+
+	describe('unknown commands without extension', () => {
+		it('should return true for unknown commands (need PATHEXT resolution)', () => {
+			expect(needsWindowsShell('mycustomtool')).toBe(true);
+			expect(needsWindowsShell('somecommand')).toBe(true);
+		});
+	});
+
+	describe('commands with other extensions', () => {
+		it('should return false for commands with unknown extensions', () => {
+			// These have an extension, so no PATHEXT resolution needed
+			expect(needsWindowsShell('script.ps1')).toBe(false);
+			expect(needsWindowsShell('tool.msi')).toBe(false);
+		});
+	});
+});

src/main/utils/execFile.ts

@@ -30,7 +30,7 @@ export interface ExecResult {
  *   to prevent percent-sign escaping issues in arguments
  * - Executables (.exe, .com) can run directly
  */
-function needsWindowsShell(command: string): boolean {
+export function needsWindowsShell(command: string): boolean {
 	const lowerCommand = command.toLowerCase();
 
 	// Batch files always need shell
@@ -45,8 +45,11 @@ function needsWindowsShell(command: string): boolean {
 
 	// Commands without extension: skip shell for known commands that have .exe variants
 	// This prevents issues like % being interpreted as environment variables on Windows
-	const knownExeCommands = ['git', 'node', 'npm', 'yarn', 'python', 'python3'];
-	if (knownExeCommands.includes(lowerCommand)) {
+	// Extract basename to handle full paths like 'C:\Program Files\Git\bin\git'
+	// Use regex to handle both Unix (/) and Windows (\) path separators
+	const knownExeCommands = new Set(['git', 'node', 'npm', 'npx', 'yarn', 'pnpm', 'python', 'python3', 'pip', 'pip3']);
+	const commandBaseName = lowerCommand.split(/[\\/]/).pop() || lowerCommand;
+	if (knownExeCommands.has(commandBaseName)) {
 		return false;
 	}