Assert: Fail test when using step inside a test without verifySteps

src/test.js

@@ -251,6 +251,13 @@ Test.prototype = {
 
 	finish: function() {
 		config.current = this;
+
+		if ( this.steps.length ) {
+			const stepsList = this.steps.join( ", " );
+			this.pushFailure( "Expected assert.verifySteps() to be called before end of test " +
+				`after using assert.step(). Unverified steps: ${stepsList}`, this.stack );
+		}
+
 		if ( config.requireExpects && this.expected === null ) {
 			this.pushFailure( "Expected number of assertions to be defined, but expect() was " +
 				"not called.", this.stack );

test/main/assert/step.js

@@ -1,7 +1,7 @@
 QUnit.module( "assert.step" );
 
 QUnit.test( "pushes a failing assertion if no message is given", function( assert ) {
-	assert.expect( 2 );
+	assert.expect( 3 );
 
 	var originalPushResult = assert.pushResult;
 	assert.pushResult = function pushResultStub( resultInfo ) {
@@ -12,10 +12,12 @@ QUnit.test( "pushes a failing assertion if no message is given", function( asser
 	};
 
 	assert.step();
+
+	assert.verifySteps( [ undefined ] );
 } );
 
 QUnit.test( "pushes a failing assertion if empty message is given", function( assert ) {
-	assert.expect( 2 );
+	assert.expect( 3 );
 
 	var originalPushResult = assert.pushResult;
 	assert.pushResult = function pushResultStub( resultInfo ) {
@@ -26,13 +28,17 @@ QUnit.test( "pushes a failing assertion if empty message is given", function( as
 	};
 
 	assert.step( "" );
+
+	assert.verifySteps( [ "" ] );
 } );
 
 QUnit.test( "pushes a passing assertion if a message is given", function( assert ) {
-	assert.expect( 2 );
+	assert.expect( 3 );
 
 	assert.step( "One step" );
 	assert.step( "Two step" );
+
+	assert.verifySteps( [ "One step", "Two step" ] );
 } );
 
 QUnit.module( "assert.verifySteps" );
@@ -88,3 +94,15 @@ QUnit.test( "resets the step list after verification", function( assert ) {
 	assert.step( "two" );
 	assert.verifySteps( [ "two" ] );
 } );
+
+QUnit.test( "errors if not called when `assert.step` is used", function( assert ) {
+	assert.expect( 2 );
+	assert.step( "one" );
+
+	var originalPushFailure = QUnit.config.current.pushFailure;
+	QUnit.config.current.pushFailure = function pushFailureStub( message ) {
+		QUnit.config.current.pushFailure = originalPushFailure;
+
+		assert.equal( message, "Expected assert.verifySteps() to be called before end of test after using assert.step(). Unverified steps: one" );
+	};
+} );