info logs now overwrite each other by default

Author: jakemac53

e2e_example/tool/watch.dart

@@ -17,11 +17,5 @@ main() async {
   /// the transitive deps issue.
   CopyBuilder.addPhases(phases, graph);
 
-  await for (var result in watch(phases)) {
-    if (result.status == BuildStatus.Success) {
-      stdout.writeln(result);
-    } else {
-      stderr.writeln(result);
-    }
-  }
+  watch(phases);
 }

lib/src/generate/build_impl.dart

@@ -65,6 +65,7 @@ class BuildImpl {
       {DateTime validAsOf, Map<AssetId, ChangeType> updates}) async {
     validAsOf ??= new DateTime.now();
     updates ??= <AssetId, ChangeType>{};
+    var watch = new Stopwatch()..start();
 
     /// Assume incremental, change if necessary.
     var buildType = BuildType.Incremental;
@@ -104,13 +105,11 @@ class BuildImpl {
               .forEach(
                   (node) => (node as GeneratedAssetNode).needsUpdate = true);
         } else {
-          var message = 'Build abandoned due to change to the build script or '
-              'one of its dependencies. This could be caused by a pub get or '
-              'any other change. Please terminate the build script and restart '
-              'it.';
-          _logger.severe(message);
           done.complete(new BuildResult(BuildStatus.Failure, buildType, [],
-              exception: message));
+              exception: 'Build abandoned due to change to the build script or '
+                  'one of its dependencies. This could be caused by a pub get '
+                  'or any other change. Please terminate the build script and '
+                  'restart it.'));
           return;
         }
       }
@@ -139,16 +138,23 @@ class BuildImpl {
           new Asset(_assetGraphId, JSON.encode(_assetGraph.serialize()));
       await _writer.writeAsString(assetGraphAsset);
 
-      _logger.info('Build succeeded');
       done.complete(result);
     }, onError: (e, Chain chain) {
-      _logger.severe('Build failed: $e\n\n${chain.terse}');
       done.complete(new BuildResult(BuildStatus.Failure, buildType, [],
           exception: e, stackTrace: chain.toTrace()));
     });
     var result = await done.future;
     _buildRunning = false;
     _isFirstBuild = false;
+    if (result.status == BuildStatus.Success) {
+      _logger.info('Succeeded after ${watch.elapsedMilliseconds}ms with '
+          '${result.outputs.length} outputs\n');
+    } else {
+      var stackTraceString =
+          result.stackTrace != null ? '\n\n${result.stackTrace}' : '';
+      _logger.severe('Failed after ${watch.elapsedMilliseconds}ms:'
+          '${result.exception}$stackTraceString\n');
+    }
     return result;
   }
 
@@ -344,13 +350,13 @@ class BuildImpl {
     // Check conflictingOuputs, prompt user to delete files.
     if (conflictingOutputs.isEmpty) return;
 
-    stdout.writeln('Found ${conflictingOutputs.length} declared outputs '
+    stdout.writeln('\n\nFound ${conflictingOutputs.length} declared outputs '
         'which already exist on disk. This is likely because the `.build` '
         'folder was deleted, or you are submitting generated files to your '
         'source repository.');
     var done = false;
     while (!done) {
-      stdout.write('Delete these files (y/n) (or list them (l))?: ');
+      stdout.write('\nDelete these files (y/n) (or list them (l))?: ');
       var input = stdin.readLineSync();
       switch (input.toLowerCase()) {
         case 'y':

lib/src/generate/options.dart

@@ -57,9 +57,11 @@ class BuildOptions {
       } else {
         color = _red;
       }
-      var message = '$color[${record.level}]$_endColor ${record.loggerName}: '
+      var message = '${Platform.isWindows ? '' : '\x1b[2K\r'}'
+          '$color[${record.level}]$_endColor ${record.loggerName}: '
           '${record.message}${record.error != null ? "\n${record.error}" : ""}'
-          '${record.stackTrace != null ? "\n${record.stackTrace}" : ""}\n';
+          '${record.stackTrace != null ? "\n${record.stackTrace}" : ""}'
+          '${record.level > Level.INFO || Platform.isWindows ? '\n' : ''}';
       if (record.level >= Level.SEVERE) {
         stderr.write(message);
       } else {

lib/src/generate/watch_impl.dart

@@ -92,7 +92,7 @@ class WatchImpl {
       await _resultStreamController.close();
     }
     _terminating = false;
-    _logger.info('Build watching terminated, safe to exit.');
+    _logger.info('Build watching terminated, safe to exit.\n');
   }
 
   /// Runs a build any time relevant files change.