clear mini reporter in watch mode

Clear the mini reporter unless the previous run had failures, or "r\n" was
entered on stdin.

Author: novemberborn

lib/logger.js

@@ -50,6 +50,14 @@ Logger.prototype.finish = function (runStatus) {
 	this.write(this.reporter.finish(runStatus), runStatus);
 };
 
+Logger.prototype.clear = function () {
+	if (!this.reporter.clear) {
+		return;
+	}
+
+	this.write(this.reporter.clear());
+};
+
 Logger.prototype.write = function (str, runStatus) {
 	if (typeof str === 'undefined') {
 		return;

lib/reporters/mini.js

@@ -193,6 +193,10 @@ MiniReporter.prototype.finish = function (runStatus) {
 	return status;
 };
 
+MiniReporter.prototype.clear = function () {
+	return '';
+};
+
 MiniReporter.prototype.write = function (str) {
 	cliCursor.hide();
 	this.currentStatus = str;

lib/watcher.js

@@ -39,10 +39,16 @@ function Watcher(logger, api, files, sources) {
 	this.isTest = makeTestMatcher(files, AvaFiles.defaultExcludePatterns());
 
 	var isFirstRun = true;
+	this.clearLogOnNextRun = true;
 	this.run = function (specificFiles) {
 		if (isFirstRun) {
 			isFirstRun = false;
 		} else {
+			if (this.clearLogOnNextRun) {
+				logger.clear();
+			}
+			this.clearLogOnNextRun = true;
+
 			logger.reset();
 			logger.start();
 		}
@@ -64,10 +70,12 @@ function Watcher(logger, api, files, sources) {
 			}
 		}
 
+		var self = this;
 		this.busy = api.run(specificFiles || files, {
 			runOnlyExclusive: runOnlyExclusive
 		}).then(function (runStatus) {
 			logger.finish(runStatus);
+			self.clearLogOnNextRun = self.clearLogOnNextRun && runStatus.failCount === 0;
 		}, rethrowAsync);
 	};
 
@@ -183,6 +191,7 @@ Watcher.prototype.observeStdin = function (stdin) {
 			// Cancel the debouncer again, it might have restarted while waiting for
 			// the busy promise to fulfil.
 			self.debouncer.cancel();
+			self.clearLogOnNextRun = false;
 			self.rerunAll();
 		});
 	});

test/logger.js

@@ -45,6 +45,23 @@ test('only write if reset is supported by reporter', function (t) {
 	t.end();
 });
 
+test('only call clear if supported by reporter', function (t) {
+	var tapReporter = tap();
+	var logger = new Logger(tapReporter);
+	tapReporter.clear = undefined;
+	logger.clear();
+	t.end();
+});
+
+test('only write if clear is supported by reporter', function (t) {
+	var tapReporter = tap();
+	var logger = new Logger(tapReporter);
+	tapReporter.clear = undefined;
+	logger.write = t.fail;
+	logger.clear();
+	t.end();
+});
+
 test('writes the reporter reset result', function (t) {
 	var tapReporter = tap();
 	var logger = new Logger(tapReporter);

test/watcher.js

@@ -60,6 +60,7 @@ group('chokidar is installed', function (beforeEach, test, group) {
 	var logger = {
 		start: sinon.spy(),
 		finish: sinon.spy(),
+		clear: sinon.spy(),
 		reset: sinon.spy()
 	};
 
@@ -102,6 +103,7 @@ group('chokidar is installed', function (beforeEach, test, group) {
 
 		logger.start.reset();
 		logger.finish.reset();
+		logger.clear.reset();
 		logger.reset.reset();
 
 		avaFiles.reset();
@@ -211,7 +213,7 @@ group('chokidar is installed', function (beforeEach, test, group) {
 	});
 
 	test('starts running the initial tests', function (t) {
-		t.plan(7);
+		t.plan(8);
 
 		var done;
 		var runStatus = {};
@@ -222,6 +224,7 @@ group('chokidar is installed', function (beforeEach, test, group) {
 		}));
 
 		start();
+		t.ok(logger.clear.notCalled);
 		t.ok(logger.reset.notCalled);
 		t.ok(logger.start.notCalled);
 		t.ok(api.run.calledOnce);
@@ -257,7 +260,7 @@ group('chokidar is installed', function (beforeEach, test, group) {
 		{label: 'is removed', fire: unlink}
 	].forEach(function (variant) {
 		test('reruns initial tests when a source file ' + variant.label, function (t) {
-			t.plan(10);
+			t.plan(12);
 
 			var runStatus = {failCount: 0};
 			api.run.returns(Promise.resolve(runStatus));
@@ -272,9 +275,12 @@ group('chokidar is installed', function (beforeEach, test, group) {
 
 			variant.fire();
 			return debounce().then(function () {
+				t.ok(logger.clear.calledOnce);
 				t.ok(logger.reset.calledOnce);
 				t.ok(logger.start.calledOnce);
 				t.ok(api.run.calledTwice);
+				// clear is called before reset.
+				t.ok(logger.clear.firstCall.calledBefore(logger.reset.firstCall));
 				// reset is called before the second run.
 				t.ok(logger.reset.firstCall.calledBefore(api.run.secondCall));
 				// reset is called before start
@@ -296,6 +302,24 @@ group('chokidar is installed', function (beforeEach, test, group) {
 		});
 	});
 
+	test('does not clear logger if the previous run had failures', function (t) {
+		t.plan(2);
+
+		api.run.returns(Promise.resolve({failCount: 1}));
+		start();
+
+		api.run.returns(Promise.resolve({failCount: 0}));
+		change();
+		return debounce().then(function () {
+			t.ok(logger.clear.notCalled);
+
+			change();
+			return debounce();
+		}).then(function () {
+			t.ok(logger.clear.calledOnce);
+		});
+	});
+
 	test('debounces by 10ms', function (t) {
 		t.plan(1);
 		api.run.returns(Promise.resolve({}));
@@ -578,6 +602,18 @@ group('chokidar is installed', function (beforeEach, test, group) {
 			});
 		});
 
+		test('entering "' + input + '" on stdin prevents the logger from being cleared', function (t) {
+			t.plan(2);
+			api.run.returns(Promise.resolve({failCount: 0}));
+			start().observeStdin(stdin);
+
+			stdin.write(input + '\n');
+			return delay().then(function () {
+				t.ok(api.run.calledTwice);
+				t.ok(logger.clear.notCalled);
+			});
+		});
+
 		test('entering "' + input + '" on stdin cancels any debouncing', function (t) {
 			t.plan(7);
 			api.run.returns(Promise.resolve({}));