Merge pull request #1270 from maximderbin/null_defined_undefined_matc…

…hers .toBeNull and .toBeDefined / .toBeUndefined
jestjs · Jul 11, 2016 · 91bc54d · 91bc54d
2 parents 0a6c992 + 0d466e7
commit 91bc54d
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diff --git a/packages/jest-matchers/src/__tests__/matchers-test.js b/packages/jest-matchers/src/__tests__/matchers-test.js
@@ -92,6 +92,44 @@ describe('.toBeNaN()', () => {
   });
 });
 
+describe('.toBeNull()', () => {
+  [{}, [], true, 1, 'a', 0.5, new Map(), () => {}, Infinity].forEach(v => {
+    test(`fails for '${stringify(v)}' with .not`, () => {
+      jestExpect(v).not.toBeNull();
+      expect(() => jestExpect(v).toBeNull())
+        .toThrowError(/expected.*to be null/);
+    });
+  });
+
+  it('pass for null', () => {
+    jestExpect(null).toBeNull();
+    expect(() => jestExpect(null).not.toBeNull())
+      .toThrowError(/expected.*not to be null/);
+  });
+});
+
+describe('.toBeDefined(), .toBeUndefined()', () => {
+  [{}, [], true, 1, 'a', 0.5, new Map(), () => {}, Infinity].forEach(v => {
+    test(`'${stringify(v)}' is defined`, () => {
+      jestExpect(v).toBeDefined();
+      jestExpect(v).not.toBeUndefined();
+      expect(() => jestExpect(v).not.toBeDefined())
+        .toThrowError(/not to be defined/);
+      expect(() => jestExpect(v).toBeUndefined())
+        .toThrowError(/to be undefined/);
+    });
+  });
+
+  test('undefined is undefined', () => {
+    jestExpect(undefined).toBeUndefined();
+    jestExpect(undefined).not.toBeDefined();
+    expect(() => jestExpect(undefined).toBeDefined())
+      .toThrowError(/to be defined/);
+    expect(() => jestExpect(undefined).not.toBeUndefined())
+      .toThrowError(/not to be undefined/);
+  });
+});
+
 describe(
   '.toBeGreaterThan(), .toBeLessThan(), ' +
     '.toBeGreaterThanOrEqual(), .toBeLessThanOrEqual()',

diff --git a/packages/jest-matchers/src/matchers.js b/packages/jest-matchers/src/matchers.js
@@ -70,6 +70,36 @@ const matchers: MatchersObject = {
     return {message, pass};
   },
 
+  toBeNull(actual: any, expected: void) {
+    ensureNoExpected(expected, 'toBeNull');
+    const pass = actual === null;
+    const message = pass
+      ? () => `expected '${stringify(actual)}' not to be null`
+      : () => `expected '${stringify(actual)}' to be null`;
+
+    return {message, pass};
+  },
+
+  toBeDefined(actual: any, expected: void) {
+    ensureNoExpected(expected, 'toBeDefined');
+    const pass = actual !== void 0;
+    const message = pass
+      ? () => `expected '${stringify(actual)}' not to be defined`
+      : () => `expected '${stringify(actual)}' to be defined`;
+
+    return {message, pass};
+  },
+
+  toBeUndefined(actual: any, expected: void) {
+    ensureNoExpected(expected, 'toBeUndefined');
+    const pass = actual === void 0;
+    const message = pass
+      ? () => `expected '${stringify(actual)}' not to be undefined`
+      : () => `expected '${stringify(actual)}' to be undefined`;
+
+    return {message, pass};
+  },
+
   toBeGreaterThan(actual: number, expected: number) {
     ensureNumbers(actual, expected, '.toBeGreaterThan');
     const pass = actual > expected;