feat(random): add enum random support

* add-random-enums

* add-random-enums

* added test for enums without value assigned
added fix for enum's with computed values

* add-random-enums

Now, if we can't access to one of enum values, instead of "0" we're set it's position
Added tests for case, when enum imported from d.ts files, and we can't access to it values

* add-random-enums

Co-authored-by: Artem Kornev <artem.kornev@y-tree.com>
Co-authored-by: Vittorio Guerriero <vittorio.gue@gmail.com>

src/random/random.ts

@@ -6,6 +6,10 @@ export class Random {
     return Math.random() * (MAX_NUMBER - MIN_NUMBER) + MIN_NUMBER;
   }
 
+  public static enumValue(...args: Array<string | number>): string | number {
+    return args[Math.floor(Math.random() * args.length)] ?? 0;
+  }
+
   public static string(prefix: string): string {
     return prefix + Math.random().toString(20).substr(2, 6);
   }

src/transformer/descriptor/enum/enumDeclaration.ts

@@ -1,12 +1,26 @@
 import * as ts from 'typescript';
 import { TypeChecker } from '../../typeChecker/typeChecker';
+import { RandomPropertyAccessor } from '../random/random';
+import { IsTsAutoMockRandomEnabled } from '../../../options/random';
 
 export function GetEnumDeclarationDescriptor(node: ts.EnumDeclaration): ts.Expression {
   const typeChecker: ts.TypeChecker = TypeChecker();
-  const type: ts.LiteralType = typeChecker.getTypeAtLocation(node.members[0]) as ts.LiteralType;
+  const typesList: ts.LiteralType[] = node.members.map((it: ts.EnumMember) => typeChecker.getTypeAtLocation(it)) as ts.LiteralType[];
 
-  if (type.hasOwnProperty('value')) {
-    return ts.createLiteral(type.value);
+  if (IsTsAutoMockRandomEnabled()) {
+    const nodesList: ts.Expression[] = typesList.map((type: ts.LiteralType, index: number) => {
+      if (type.hasOwnProperty('value')) {
+        return ts.createLiteral(type.value);
+      }
+
+      return ts.createLiteral(index);
+    });
+
+    return ts.createCall(RandomPropertyAccessor('enumValue'), [], [...nodesList]);
+  }
+
+  if (typesList[0].hasOwnProperty('value')) {
+    return ts.createLiteral(typesList[0].value);
   }
 
   return ts.createLiteral(0);

test/features/random/enum.test.ts

@@ -0,0 +1,126 @@
+import { createMock } from 'ts-auto-mock';
+
+describe('Random enum', () => {
+  it('should have random enum values', () => {
+    enum EnumType {
+      firstValue = 'firstValue',
+      secondValue = 'secondValue',
+      thirdValue = 2,
+    }
+
+    type WithEnum = {
+      propertyName: EnumType;
+    };
+
+    const spy: jasmine.Spy = spyOn(Math, 'floor');
+
+    spy.and.returnValue(0);
+    const firstMock: WithEnum = createMock<WithEnum>();
+
+    expect(firstMock.propertyName).toBe(EnumType.firstValue);
+
+    spy.and.returnValue(1);
+    const secondMock: WithEnum = createMock<WithEnum>();
+
+    expect(secondMock.propertyName).toBe(EnumType.secondValue);
+
+    spy.and.returnValue(2);
+    const thirdMock: WithEnum = createMock<WithEnum>();
+
+    expect(thirdMock.propertyName).toBe(EnumType.thirdValue);
+
+    // Should have 0, when does't have value in array
+    spy.and.returnValue(100);
+    const fourthMock: WithEnum = createMock<WithEnum>();
+
+    expect(fourthMock.propertyName).toBe(0);
+  });
+
+  it('should have 0 value, when enum empty', () => {
+    enum EmptyEnum {}
+
+    type WithEmptyEnum = {
+      propertyName: EmptyEnum;
+    };
+
+    const mock: WithEmptyEnum = createMock<WithEmptyEnum>();
+
+    expect(mock.propertyName).toBe(0);
+  });
+
+  describe('for enum from a module', () => {
+    it('should assign correct random value', () => {
+      // We cannot check against the real ENUM because is a d.ts, it cannot be used as a value
+      const spy: jasmine.Spy = spyOn(Math, 'floor');
+      spy.and.returnValue(0);
+
+      const mock1: NameSpace.WithEnum = createMock<NameSpace.WithEnum>();
+
+      expect(mock1.propertyWithoutDefaultValue).toBe(0);
+      expect(mock1.propertyWithDefaultValue).toBe('1');
+
+      spy.and.returnValue(1);
+      const mock2: NameSpace.WithEnum = createMock<NameSpace.WithEnum>();
+
+      expect(mock2.propertyWithoutDefaultValue).toBe(1);
+      expect(mock2.propertyWithDefaultValue).toBe('2');
+    });
+  });
+
+  it('const enum declaration should work correctly with random', () => {
+    const enum Direction {
+      Up,
+      Down,
+      None = 'Nothing'
+    }
+
+    interface Movement {
+      direction: Direction;
+    }
+
+    const spy: jasmine.Spy = spyOn(Math, 'floor');
+
+    spy.and.returnValue(0);
+    const firstMock: Movement = createMock<Movement>();
+
+    expect(firstMock.direction).toBe(Direction.Up);
+
+    spy.and.returnValue(1);
+    const secondMock: Movement = createMock<Movement>();
+
+    expect(secondMock.direction).toBe(Direction.Down);
+
+    spy.and.returnValue(2);
+    const thirdMock: Movement = createMock<Movement>();
+
+    expect(thirdMock.direction).toBe(Direction.None);
+  });
+
+  it('should have position of "computed" property, because transformer don\'t support computed Enum values', () => {
+    // Issue https://github.com/Typescript-TDD/ts-auto-mock/issues/339
+    function getComputed(): number {
+      return 12;
+    }
+
+    enum WithComputed {
+      Computed = getComputed(),
+      Computed2 = 1 + 4,
+    }
+
+    interface IWithComputed {
+      computed: WithComputed;
+    }
+
+    const spy: jasmine.Spy = spyOn(Math, 'floor');
+
+    spy.and.returnValue(0);
+    const mock1: IWithComputed = createMock<IWithComputed>();
+
+    expect(mock1.computed).toBe(0);
+
+    spy.and.returnValue(1);
+    const mock2: IWithComputed = createMock<IWithComputed>();
+
+    expect(mock2.computed).toBe(1);
+  });
+});