fix(mason_logger): improve clear line mechanism for Progress API (#549)

felangel · Oct 19, 2022 · 68b98c7 · 68b98c7
1 parent 8641f26
commit 68b98c7
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Showing 2 changed files with 51 additions and 30 deletions.
diff --git a/packages/mason_logger/lib/src/progress.dart b/packages/mason_logger/lib/src/progress.dart
@@ -72,54 +72,51 @@ class Progress {
   void complete([String? update]) {
     _stopwatch.stop();
     _write(
-      '''$_clearLn${lightGreen.wrap('✓')} ${update ?? _message} $_time\n''',
+      '''$_clearLine${lightGreen.wrap('✓')} ${update ?? _message} $_time\n''',
     );
     _timer.cancel();
   }
 
   /// End the progress and mark it as failed.
   void fail([String? update]) {
     _timer.cancel();
-    _write('$_clearLn${red.wrap('✗')} ${update ?? _message} $_time\n');
+    _write('$_clearLine${red.wrap('✗')} ${update ?? _message} $_time\n');
     _stopwatch.stop();
   }
 
   /// Update the progress message.
   void update(String update) {
-    _write(_clearLn);
+    _write(_clearLine);
     _message = update;
     _onTick(_timer);
   }
 
   /// Cancel the progress and remove the written line.
   void cancel() {
     _timer.cancel();
-    _write(_clearLn);
+    _write(_clearLine);
     _stopwatch.stop();
   }
 
+  String get _clearLine {
+    return '\u001b[2K' // clear current line
+        '\r'; // bring cursor to the start of the current line
+  }
+
   void _onTick(Timer _) {
     _index++;
     final frames = _options.animation.frames;
     final char = frames.isEmpty ? '' : frames[_index % frames.length];
-    final prefix = char.isEmpty
-        ? _clearMessageLength
-        : '${lightGreen.wrap('$_clearMessageLength$char')} ';
-    _write('$prefix$_message... $_time');
+    final prefix = char.isEmpty ? char : '${lightGreen.wrap(char)} ';
+
+    _write('$_clearLine$prefix$_message... $_time');
   }
 
-  void _write(Object? object) {
+  void _write(String object) {
     if (_level.index > Level.info.index) return;
     _stdout.write(object);
   }
 
-  String get _clearMessageLength {
-    final length = _message.length + 4 + _time.length;
-    return '\b${'\b' * length}';
-  }
-
-  String get _clearLn => '$_clearMessageLength\u001b[2K';
-
   String get _time {
     final elapsedTime = _stopwatch.elapsed.inMilliseconds;
     final displayInMilliseconds = elapsedTime < 100;

diff --git a/packages/mason_logger/test/src/progress_test.dart b/packages/mason_logger/test/src/progress_test.dart
@@ -122,7 +122,6 @@ void main() {
           () async {
             await IOOverrides.runZoned(
               () async {
-                const time = '(0.1s)';
                 const message = 'test message';
                 final progress = Logger().progress(message);
                 await Future<void>.delayed(const Duration(milliseconds: 100));
@@ -131,17 +130,20 @@ void main() {
                   () {
                     stdout.write(
                       any(
-                        that: contains(
-                          '''[92m⠙[0m $message... [90m''',
+                        that: matches(
+                          RegExp(
+                            r'\[2K\u000D\[92m⠙\[0m test message... \[90m\(8\dms\)\[0m',
+                          ),
                         ),
                       ),
                     );
                   },
                 ).called(1);
+
                 verify(
                   () {
                     stdout.write(
-                      '''[2K[92m✓[0m $message [90m$time[0m\n''',
+                      '''[2K\r[92m✓[0m test message [90m(0.1s)[0m\n''',
                     );
                   },
                 ).called(1);
@@ -180,26 +182,35 @@ void main() {
               () async {
                 const message = 'message';
                 const update = 'update';
-                const time = '(0.1s)';
                 final progress = Logger().progress(message);
                 await Future<void>.delayed(const Duration(milliseconds: 100));
                 progress.update(update);
                 await Future<void>.delayed(const Duration(milliseconds: 100));
+
                 verify(
                   () {
                     stdout.write(
                       any(
-                        that: contains(
-                          '''[92m⠙[0m $message... [90m''',
+                        that: matches(
+                          RegExp(
+                            r'\[2K\u000D\[92m⠙\[0m message... \[90m\(8\dms\)\[0m',
+                          ),
                         ),
                       ),
                     );
                   },
                 ).called(1);
+
                 verify(
                   () {
                     stdout.write(
-                      '''[92m⠹[0m $update... [90m$time[0m''',
+                      any(
+                        that: matches(
+                          RegExp(
+                            r'\[2K\u000D\[92m⠹\[0m update... \[90m\(0\.1s\)\[0m',
+                          ),
+                        ),
+                      ),
                     );
                   },
                 ).called(1);
@@ -243,21 +254,25 @@ void main() {
                 final progress = Logger().progress(message);
                 await Future<void>.delayed(const Duration(milliseconds: 100));
                 progress.fail();
+
                 verify(
                   () {
                     stdout.write(
                       any(
-                        that: contains(
-                          '''[92m⠙[0m $message... [90m''',
+                        that: matches(
+                          RegExp(
+                            r'\[2K\u000D\[92m⠙\[0m test message... \[90m\(8\dms\)\[0m',
+                          ),
                         ),
                       ),
                     );
                   },
                 ).called(1);
+
                 verify(
                   () {
                     stdout.write(
-                      '''[2K[31m✗[0m $message [90m$time[0m\n''',
+                      '''[2K\u000D[31m✗[0m $message [90m$time[0m\n''',
                     );
                   },
                 ).called(1);
@@ -302,17 +317,26 @@ void main() {
                   () {
                     stdout.write(
                       any(
-                        that: contains(
-                          '''[92m⠙[0m $message... [90m''',
+                        that: matches(
+                          RegExp(
+                            r'\[2K\u000D\[92m⠙\[0m test message... \[90m\(8\dms\)\[0m',
+                          ),
                         ),
                       ),
                     );
                   },
                 ).called(1);
+
                 verify(
                   () {
                     stdout.write(
-                      '''[2K''',
+                      any(
+                        that: matches(
+                          RegExp(
+                            r'\[2K\u000D',
+                          ),
+                        ),
+                      ),
                     );
                   },
                 ).called(1);