Add startsWith() and endsWith() string matchers

Author: johanblumenberg

src/matcher/type/EndsWithMatcher.ts

@@ -0,0 +1,15 @@
+import { Matcher } from "./Matcher";
+
+export class EndsWithMatcher extends Matcher {
+    constructor(private expectedValue: any) {
+        super();
+    }
+
+    public match(value: Object): boolean {
+        return value && (typeof value === "string") && value.endsWith(this.expectedValue);
+    }
+
+    public toString(): string {
+        return `endsWith(${this.expectedValue})`;
+    }
+}

src/matcher/type/StartsWithMatcher.ts

@@ -0,0 +1,15 @@
+import { Matcher } from "./Matcher";
+
+export class StartsWithMatcher extends Matcher {
+    constructor(private expectedValue: any) {
+        super();
+    }
+
+    public match(value: Object): boolean {
+        return value && (typeof value === "string") && value.startsWith(this.expectedValue);
+    }
+
+    public toString(): string {
+        return `startsWith(${this.expectedValue})`;
+    }
+}

src/ts-mockito.ts

@@ -18,9 +18,11 @@ import {AnyStringMatcher} from "./matcher/type/AnyStringMatcher";
 import {AnythingMatcher} from "./matcher/type/AnythingMatcher";
 import {BetweenMatcher} from "./matcher/type/BetweenMatcher";
 import {DeepEqualMatcher} from "./matcher/type/DeepEqualMatcher";
+import {EndsWithMatcher} from "./matcher/type/EndsWithMatcher";
 import {MatchingStringMatcher} from "./matcher/type/MatchingStringMatcher";
 import {NotNullMatcher} from "./matcher/type/NotNullMatcher";
 import {ObjectContainingMatcher} from "./matcher/type/ObjectContainingMatcher";
+import {StartsWithMatcher} from "./matcher/type/StartsWithMatcher";
 import {StrictEqualMatcher} from "./matcher/type/StrictEqualMatcher";
 import {MethodStubSetter} from "./MethodStubSetter";
 import {MethodStubVerificator} from "./MethodStubVerificator";
@@ -119,6 +121,14 @@ export function match(expectedValue: RegExp | string): any {
     return new MatchingStringMatcher(expectedValue) as any;
 }
 
+export function startsWith(expectedValue: string): string {
+    return new StartsWithMatcher(expectedValue) as any;
+}
+
+export function endsWith(expectedValue: string): string {
+    return new EndsWithMatcher(expectedValue) as any;
+}
+
 export function objectContaining(expectedValue: Object): any {
     return new ObjectContainingMatcher(expectedValue) as any;
 }
@@ -143,5 +153,7 @@ export default {
     notNull,
     strictEqual,
     match,
+    startsWith,
+    endsWith,
     objectContaining,
 };

test/matcher/type/EndsWithMatcher.spec.ts

@@ -0,0 +1,32 @@
+import {Matcher} from "../../../src/matcher/type/Matcher";
+import {endsWith} from "../../../src/ts-mockito";
+
+describe("EndsWithMatcher", () => {
+    describe("checking if value starts with given value", () => {
+        const testObj: Matcher = endsWith("abc") as any;
+
+        describe("when given value ends with string", () => {
+            it("returns true", () => {
+                // when
+                const result = testObj.match("123 abc");
+
+                // then
+                expect(result).toBeTruthy();
+            });
+
+            it("describes the matcher", () => {
+                expect(testObj.toString()).toEqual("endsWith(abc)");
+            });
+        });
+
+        describe("when given value doesn\'t end with string", () => {
+            it("returns false", () => {
+                // when
+                const result = testObj.match("abc 123");
+
+                // then
+                expect(result).toBeFalsy();
+            });
+        });
+    });
+});

test/matcher/type/StartsWithMatcher.spec.ts

@@ -0,0 +1,32 @@
+import {Matcher} from "../../../src/matcher/type/Matcher";
+import {startsWith} from "../../../src/ts-mockito";
+
+describe("StartsWithMatcher", () => {
+    describe("checking if value starts with given value", () => {
+        const testObj: Matcher = startsWith("abc") as any;
+
+        describe("when given value starts with string", () => {
+            it("returns true", () => {
+                // when
+                const result = testObj.match("abc 123");
+
+                // then
+                expect(result).toBeTruthy();
+            });
+
+            it("describes the matcher", () => {
+                expect(testObj.toString()).toEqual("startsWith(abc)");
+            });
+        });
+
+        describe("when given value doesn\'t start with string", () => {
+            it("returns false", () => {
+                // when
+                const result = testObj.match("123 abc");
+
+                // then
+                expect(result).toBeFalsy();
+            });
+        });
+    });
+});