chore: migrate test cases from Chai to Jest

src/fs/fs-impl.spec.ts

@@ -0,0 +1,53 @@
+import * as fs from './fs-impl'
+import * as path from 'path'
+
+describe('fs-impl', function () {
+  describe('.resolve()', function () {
+    it('should resolve based on root', async function () {
+      const filepath = fs.resolve('/foo', 'bar.html', '.liquid')
+      const expected = path.resolve('/foo/bar.html')
+      return expect(filepath).toBe(expected)
+    })
+    it('should add extension if it has no extension', async function () {
+      const filepath = fs.resolve('/foo', 'bar', '.liquid')
+      const expected = path.resolve('/foo/bar.liquid')
+      return expect(filepath).toBe(expected)
+    })
+  })
+  describe('.existsSync', () => {
+    it('should resolve as false if not exists', () => {
+      expect(fs.existsSync('/foo/bar')).toBeFalsy()
+    })
+    it('should resolve as true if exists', () => {
+      expect(fs.existsSync(__filename)).toBeTruthy()
+    })
+  })
+  describe('.exists', () => {
+    it('should resolve as false if not exists', async () => {
+      const result = await fs.exists('/foo/bar')
+      expect(result).toBeFalsy()
+    })
+    it('should resolve as true if exists', async () => {
+      const result = await fs.exists(__filename)
+      expect(result).toBeTruthy()
+    })
+  })
+  describe('.readFileSync', function () {
+    it('should throw when not exist', function () {
+      return expect(() => fs.readFileSync('/foo/bar')).toThrow('ENOENT')
+    })
+    it('should read content if exists', function () {
+      const content = fs.readFileSync(__filename)
+      expect(content).toContain('should read content if exists')
+    })
+  })
+  describe('.readFile', function () {
+    it('should throw when not exist', function () {
+      return expect(fs.readFile('/foo/bar')).rejects.toHaveProperty('message', expect.stringMatching('ENOENT'))
+    })
+    it('should read content if exists', async function () {
+      const content = await fs.readFile(__filename)
+      expect(content).toContain('should read content if exists')
+    })
+  })
+})