test: negative cases, cleanup a bit, add mockFetch helpers for clarity

Author: devdumpling

test/unit/file-tree.spec.ts

@@ -4,6 +4,30 @@ import { convertToFileTree, fetchFileTree, getPackageFileTree } from '../../serv
 
 const getChildren = (node?: PackageFileTree): PackageFileTree[] => node?.children ?? []
 
+const mockFetchOk = <T>(body: T) => {
+  const fetchMock = vi.fn().mockResolvedValue({
+    ok: true,
+    json: async () => body,
+  })
+  vi.stubGlobal('fetch', fetchMock)
+  return fetchMock
+}
+
+const mockFetchError = (status: number) => {
+  const fetchMock = vi.fn().mockResolvedValue({
+    ok: false,
+    status,
+  })
+  vi.stubGlobal('fetch', fetchMock)
+  return fetchMock
+}
+
+const mockCreateError = () => {
+  const createErrorMock = vi.fn((opts: { statusCode: number; message: string }) => opts)
+  vi.stubGlobal('createError', createErrorMock)
+  return createErrorMock
+}
+
 describe('convertToFileTree', () => {
   it('converts jsDelivr nodes to a sorted tree with directories first', () => {
     const input: JsDelivrFileNode[] = [
@@ -72,6 +96,20 @@ describe('convertToFileTree', () => {
     const empty: PackageFileTree[] = []
     expect(tree).toEqual(empty)
   })
+
+  it('handles directories without a files property', () => {
+    const input: JsDelivrFileNode[] = [
+      {
+        type: 'directory',
+        name: 'src',
+      },
+    ]
+
+    const tree = convertToFileTree(input)
+
+    expect(tree[0]?.type).toBe('directory')
+    expect(tree[0]?.children).toEqual([])
+  })
 })
 
 describe('fetchFileTree', () => {
@@ -84,12 +122,7 @@ describe('fetchFileTree', () => {
       files: [],
     }
 
-    const fetchMock = vi.fn().mockResolvedValue({
-      ok: true,
-      json: async () => body,
-    })
-
-    vi.stubGlobal('fetch', fetchMock)
+    mockFetchOk(body)
 
     try {
       const result = await fetchFileTree('pkg', '1.0.0')
@@ -100,15 +133,8 @@ describe('fetchFileTree', () => {
   })
 
   it('throws a 404 error when package is not found', async () => {
-    const fetchMock = vi.fn().mockResolvedValue({
-      ok: false,
-      status: 404,
-    })
-
-    const createErrorMock = vi.fn((opts: { statusCode: number; message: string }) => opts)
-
-    vi.stubGlobal('fetch', fetchMock)
-    vi.stubGlobal('createError', createErrorMock)
+    mockFetchError(404)
+    mockCreateError()
 
     try {
       await expect(fetchFileTree('pkg', '1.0.0')).rejects.toMatchObject({ statusCode: 404 })
@@ -118,15 +144,8 @@ describe('fetchFileTree', () => {
   })
 
   it('throws a 502 error for non-404 failures', async () => {
-    const fetchMock = vi.fn().mockResolvedValue({
-      ok: false,
-      status: 500,
-    })
-
-    const createErrorMock = vi.fn((opts: { statusCode: number; message: string }) => opts)
-
-    vi.stubGlobal('fetch', fetchMock)
-    vi.stubGlobal('createError', createErrorMock)
+    mockFetchError(500)
+    mockCreateError()
 
     try {
       await expect(fetchFileTree('pkg', '1.0.0')).rejects.toMatchObject({ statusCode: 502 })
@@ -152,12 +171,7 @@ describe('getPackageFileTree', () => {
       ],
     }
 
-    const fetchMock = vi.fn().mockResolvedValue({
-      ok: true,
-      json: async () => body,
-    })
-
-    vi.stubGlobal('fetch', fetchMock)
+    mockFetchOk(body)
 
     try {
       const result = await getPackageFileTree('pkg', '1.0.0')
@@ -170,4 +184,22 @@ describe('getPackageFileTree', () => {
       vi.unstubAllGlobals()
     }
   })
+
+  it('returns undefined when default is missing', async () => {
+    const body = {
+      type: 'npm',
+      name: 'pkg',
+      version: '1.0.0',
+      files: [],
+    }
+
+    mockFetchOk(body)
+
+    try {
+      const result = await getPackageFileTree('pkg', '1.0.0')
+      expect(result.default).toBeUndefined()
+    } finally {
+      vi.unstubAllGlobals()
+    }
+  })
 })

test/unit/import-resolver.spec.ts

@@ -31,6 +31,23 @@ describe('flattenFileTree', () => {
     expect(files.has('dist/utils/format.js')).toBe(true)
     expect(files.has('dist/utils')).toBe(false)
   })
+
+  it('returns an empty set for an empty tree', () => {
+    const files = flattenFileTree([])
+    expect(files.size).toBe(0)
+  })
+
+  it('includes root-level files', () => {
+    const tree: PackageFileTree[] = [
+      { name: 'index.js', path: 'index.js', type: 'file', size: 5 },
+      { name: 'cli.js', path: 'cli.js', type: 'file', size: 3 },
+    ]
+
+    const files = flattenFileTree(tree)
+
+    expect(files.has('index.js')).toBe(true)
+    expect(files.has('cli.js')).toBe(true)
+  })
 })
 
 describe('resolveRelativeImport', () => {
@@ -55,6 +72,20 @@ describe('resolveRelativeImport', () => {
     expect(resolved?.path).toBe('dist/types.d.ts')
   })
 
+  it('resolves an exact extension match', () => {
+    const files = new Set<string>(['src/utils.ts', 'src/utils.js'])
+    const resolved = resolveRelativeImport('./utils.ts', 'src/index.ts', files)
+
+    expect(resolved?.path).toBe('src/utils.ts')
+  })
+
+  it('resolves a quoted specifier', () => {
+    const files = new Set<string>(['dist/utils.js'])
+    const resolved = resolveRelativeImport("'./utils'", 'dist/index.js', files)
+
+    expect(resolved?.path).toBe('dist/utils.js')
+  })
+
   it('resolves a relative import with extension priority for MTS files', () => {
     const files = new Set<string>(['src/utils.mts', 'src/utils.mjs', 'src/utils.ts'])
     const resolved = resolveRelativeImport('./utils', 'src/index.mts', files)
@@ -128,4 +159,22 @@ describe('createImportResolver', () => {
 
     expect(url).toBe('/code/pkg-name/v/1.2.3/dist/utils.js')
   })
+
+  it('returns null when the import cannot be resolved', () => {
+    const files = new Set<string>(['dist/utils.js'])
+    const resolver = createImportResolver(files, 'dist/index.js', 'pkg-name', '1.2.3')
+
+    const url = resolver('./missing')
+
+    expect(url).toBeNull()
+  })
+
+  it('handles scoped package names in URLs', () => {
+    const files = new Set<string>(['dist/utils.js'])
+    const resolver = createImportResolver(files, 'dist/index.js', '@scope/pkg', '1.2.3')
+
+    const url = resolver('./utils')
+
+    expect(url).toBe('/code/@scope/pkg/v/1.2.3/dist/utils.js')
+  })
 })