test(type-utils): add unit tests for requiresQuoting (#8691)

* test: add testCase

* test: fix test case result

* docs: add comment in testcase and function

packages/type-utils/src/requiresQuoting.ts

@@ -1,5 +1,5 @@
 import * as ts from 'typescript';
-
+/*** Indicates whether identifiers require the use of quotation marks when accessing property definitions and dot notation. */
 function requiresQuoting(
   name: string,
   target: ts.ScriptTarget = ts.ScriptTarget.ESNext,

packages/type-utils/tests/requiresQuoting.test.ts

@@ -0,0 +1,86 @@
+import { requiresQuoting } from '../src';
+
+describe('getDeclaration', () => {
+  describe('valid identifier', () => {
+    it('upper and lower case alphabet', () => {
+      const name = 'c';
+      const result = requiresQuoting(name);
+      expect(result).toBe(false);
+    });
+
+    it('upper and lower case alphabet with number not first', () => {
+      const name = 'foo1234Bar';
+      const result = requiresQuoting(name);
+      expect(result).toBe(false);
+    });
+
+    it('start with dollorSign', () => {
+      const name = '$bar';
+      const result = requiresQuoting(name);
+      expect(result).toBe(false);
+    });
+    it('include dollorSign not start position', () => {
+      const name = 'foo$bar';
+      const result = requiresQuoting(name);
+      expect(result).toBe(false);
+    });
+
+    it('start with underScore', () => {
+      const name = '_bar';
+      const result = requiresQuoting(name);
+      expect(result).toBe(false);
+    });
+    it('include underScore not start position', () => {
+      const name = 'foo_bar';
+      const result = requiresQuoting(name);
+      expect(result).toBe(false);
+    });
+
+    it('non-alphabet characters', () => {
+      const name = 'café';
+      const result = requiresQuoting(name);
+      expect(result).toBe(false);
+    });
+  });
+
+  describe('invalid identifier', () => {
+    // This test case is written because it is possible to access object properties, but dot annotation is not accessible.
+    it('only number', () => {
+      const name = '12345';
+      const result = requiresQuoting(name);
+      expect(result).toBe(true);
+    });
+    it('start with number', () => {
+      const name = '1axcef';
+      const result = requiresQuoting(name);
+      expect(result).toBe(true);
+    });
+    it('start with dash', () => {
+      const name = '-bar';
+      const result = requiresQuoting(name);
+      expect(result).toBe(true);
+    });
+    it('include dash not start position', () => {
+      const name = 'foo-bar';
+      const result = requiresQuoting(name);
+      expect(result).toBe(true);
+    });
+    it('empty string', () => {
+      const name = '';
+      const result = requiresQuoting(name);
+      expect(result).toBe(true);
+    });
+    it('include special symbol at first', () => {
+      const name = '!asdfs';
+      const result = requiresQuoting(name);
+      expect(result).toBe(true);
+    });
+
+    it('include special symbol at middle', () => {
+      const name = 'asd!fs';
+      const result = requiresQuoting(name);
+
+      expect(result).toBe(true);
+    });
+  });
+});