Fix remaining Windows CI test failures

- Skip Unix shell tests (/bin/sh) on Windows
- Fix Windows file URL regex to accept backslashes or forward slashes
- Fix case-insensitive path comparison on Windows in relative() function
- Add promise catch handlers to prevent unhandled rejections in agent tests

Author: jdalton

src/path.ts

@@ -983,17 +983,30 @@ function relative(from: string, to: string): string {
   let i = 0
 
   for (; i < length; i += 1) {
-    const fromCode = actualFrom.charCodeAt(fromStart + i)
-    const toCode = actualTo.charCodeAt(toStart + i)
+    let fromCode = actualFrom.charCodeAt(fromStart + i)
+    let toCode = actualTo.charCodeAt(toStart + i)
 
     // Paths diverge at this character.
+    // On Windows, perform case-insensitive comparison.
+    if (WIN32) {
+      // Normalize to lowercase for case-insensitive comparison.
+      // Convert A-Z (65-90) to a-z (97-122).
+      if (fromCode >= CHAR_UPPERCASE_A && fromCode <= CHAR_UPPERCASE_Z) {
+        fromCode += 32
+      }
+      if (toCode >= CHAR_UPPERCASE_A && toCode <= CHAR_UPPERCASE_Z) {
+        toCode += 32
+      }
+    }
+
     if (fromCode !== toCode) {
       break
     }
 
     // Track directory separators (both forward and backslash for Windows compatibility).
     // We need this to ensure we only split at directory boundaries.
-    if (isPathSeparator(fromCode)) {
+    // Use original fromCode from actualFrom (before case normalization).
+    if (isPathSeparator(actualFrom.charCodeAt(fromStart + i))) {
       lastCommonSep = i
     }
   }

test/agent.test.ts

@@ -474,6 +474,8 @@ describe('agent', () => {
       it('should have a function that returns a promise', () => {
         const result = execNpm(['--version'])
         expect(result).toBeInstanceOf(Promise)
+        // Catch promise to prevent unhandled rejection on Windows.
+        result.catch(() => {})
       })
 
       it('should be a function', () => {
@@ -485,6 +487,8 @@ describe('agent', () => {
       it('should have a function that returns a promise', () => {
         const result = execPnpm(['--version'])
         expect(result).toBeInstanceOf(Promise)
+        // Catch promise to prevent unhandled rejection on Windows.
+        result.catch(() => {})
       })
 
       it('should be a function', () => {
@@ -496,6 +500,8 @@ describe('agent', () => {
       it('should have a function that returns a promise', () => {
         const result = execYarn(['--version'])
         expect(result).toBeInstanceOf(Promise)
+        // Catch promise to prevent unhandled rejection on Windows.
+        result.catch(() => {})
       })
 
       it('should be a function', () => {
@@ -507,6 +513,8 @@ describe('agent', () => {
       it('should have a function that returns a promise', () => {
         const result = execScript('test')
         expect(result).toBeInstanceOf(Promise)
+        // Catch promise to prevent unhandled rejection on Windows.
+        result.catch(() => {})
       })
 
       it('should be a function', () => {
@@ -516,18 +524,24 @@ describe('agent', () => {
       it('should handle script name with array args', () => {
         const result = execScript('test', ['--coverage'])
         expect(result).toBeInstanceOf(Promise)
+        // Catch promise to prevent unhandled rejection on Windows.
+        result.catch(() => {})
       })
 
       it('should handle script name with options object', () => {
         const result = execScript('test', { cwd: process.cwd() })
         expect(result).toBeInstanceOf(Promise)
+        // Catch promise to prevent unhandled rejection on Windows.
+        result.catch(() => {})
       })
 
       it('should handle script name with args and options', () => {
         const result = execScript('test', ['--coverage'], {
           cwd: process.cwd(),
         })
         expect(result).toBeInstanceOf(Promise)
+        // Catch promise to prevent unhandled rejection on Windows.
+        result.catch(() => {})
       })
     })
   })

test/path.test.ts

@@ -521,10 +521,10 @@ describe('path utilities', () => {
       it('should handle Windows file URLs', () => {
         if (process.platform === 'win32') {
           expect(pathLikeToString(new URL('file:///C:/Windows'))).toMatch(
-            /^C:\//,
+            /^C:[\\/]/,
           )
           expect(pathLikeToString(new URL('file:///D:/data/file.txt'))).toMatch(
-            /^D:\//,
+            /^D:[\\/]/,
           )
         }
       })

test/spawn.test.ts

@@ -279,12 +279,15 @@ describe('spawn', () => {
       expect(result.code).toBe(0)
     })
 
-    it('should handle shell as string path', async () => {
-      const result = await spawn('echo', ['hello'], {
-        shell: '/bin/sh',
-      })
-      expect(result.code).toBe(0)
-    })
+    it.skipIf(process.platform === 'win32')(
+      'should handle shell as string path',
+      async () => {
+        const result = await spawn('echo', ['hello'], {
+          shell: '/bin/sh',
+        })
+        expect(result.code).toBe(0)
+      },
+    )
 
     it('should handle undefined args', async () => {
       const result = await spawn('pwd', undefined)
@@ -415,12 +418,15 @@ describe('spawn', () => {
       expect(result.status).toBe(0)
     })
 
-    it('should handle shell as string path', () => {
-      const result = spawnSync('echo', ['hello'], {
-        shell: '/bin/sh',
-      })
-      expect(result.status).toBe(0)
-    })
+    it.skipIf(process.platform === 'win32')(
+      'should handle shell as string path',
+      () => {
+        const result = spawnSync('echo', ['hello'], {
+          shell: '/bin/sh',
+        })
+        expect(result.status).toBe(0)
+      },
+    )
 
     it('should handle undefined args', () => {
       const result = spawnSync('pwd', undefined)