Packages: jest-console: Capture logging in test lifecycle

packages/jest-console/CHANGELOG.md

@@ -1,3 +1,9 @@
+## 2.0.1 (Unreleased)
+
+### Bug Fixes
+
+- Captures and protects against unexpected console logging occurring during lifecycle.
+
 ## 2.0.0 (2018-07-12)
 
 ### Breaking Change

packages/jest-console/src/index.js

@@ -18,16 +18,31 @@ import supportedMatchers from './supported-matchers';
 const setConsoleMethodSpy = ( matcherName, methodName ) => {
 	const spy = jest.spyOn( console, methodName ).mockName( `console.${ methodName }` );
 
-	beforeEach( () => {
+	/**
+	 * Resets the spy to its initial state.
+	 */
+	function resetSpy() {
 		spy.mockReset();
 		spy.assertionsNumber = 0;
-	} );
+	}
 
-	afterEach( () => {
+	/**
+	 * Verifies that the spy has only been called if expected.
+	 */
+	function assertExpectedCalls() {
 		if ( spy.assertionsNumber === 0 && spy.mock.calls.length > 0 ) {
 			expect( console ).not[ matcherName ]();
 		}
+	}
+
+	beforeAll( resetSpy );
+
+	beforeEach( () => {
+		assertExpectedCalls();
+		resetSpy();
 	} );
+
+	afterEach( assertExpectedCalls );
 };
 
 forEach( supportedMatchers, setConsoleMethodSpy );

packages/jest-console/src/test/index.test.js

@@ -72,6 +72,18 @@ describe( 'jest-console', () => {
 					expect( console )[ matcherNameWith ]( message );
 					expect( spy.assertionsNumber ).toBe( 2 );
 				} );
+
+				describe( 'lifecycle', () => {
+					beforeAll( () => {
+						// This is a difficult one to test, since the matcher's
+						// own lifecycle is defined to run before ours. Infer
+						// that we're being watched by testing the console
+						// method as being a spy.
+						expect( console[ methodName ].assertionsNumber ).toBeGreaterThanOrEqual( 0 );
+					} );
+
+					it( 'captures logging in lifecycle', () => {} );
+				} );
 			} );
 		}
 	);