Use Stdout.terminalColumns for line length (flutter#716)

Use Stdout.terminalColumns for line length

Fall back on a 200-character default, which is less likely to obscure
test names when printing to a non-terminal destination.

Closes flutter#86

CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.12.27
+
+* When running in an interactive terminal, the test runner now prints status
+  lines as wide as the terminal and no wider.
+
 ## 0.12.26+1
 
 * Fix lower bound on package `stack_trace`. Now 1.6.0.

lib/src/runner/reporter/compact.dart

@@ -11,17 +11,13 @@ import '../../backend/message.dart';
 import '../../backend/state.dart';
 import '../../utils.dart';
 import '../../utils.dart' as utils;
+import '../../util/io.dart';
 import '../configuration.dart';
 import '../engine.dart';
 import '../load_exception.dart';
 import '../load_suite.dart';
 import '../reporter.dart';
 
-/// The maximum console line length.
-///
-/// Lines longer than this will be cropped.
-const _lineLength = 100;
-
 /// A reporter that prints test results to the console in a single
 /// continuously-updating line.
 class CompactReporter implements Reporter {
@@ -251,7 +247,7 @@ class CompactReporter implements Reporter {
       stdout.write(message);
 
       // Add extra padding to overwrite any load messages.
-      if (!_printedNewline) stdout.write(" " * (_lineLength - message.length));
+      if (!_printedNewline) stdout.write(" " * (lineLength - message.length));
       stdout.writeln();
     } else if (!success) {
       _progressLine('Some tests failed.', color: _red);
@@ -268,7 +264,7 @@ class CompactReporter implements Reporter {
   /// Prints a line representing the current state of the tests.
   ///
   /// [message] goes after the progress report, and may be truncated to fit the
-  /// entire line within [_lineLength]. If [color] is passed, it's used as the
+  /// entire line within [lineLength]. If [color] is passed, it's used as the
   /// color for [message]. If [suffix] is passed, it's added to the end of
   /// [message].
   bool _progressLine(String message,
@@ -329,16 +325,16 @@ class CompactReporter implements Reporter {
     buffer.write(': ');
     buffer.write(color);
 
-    // Ensure the line fits within [_lineLength]. [buffer] includes the color
+    // Ensure the line fits within [lineLength]. [buffer] includes the color
     // escape sequences too. Because these sequences are not visible characters,
     // we make sure they are not counted towards the limit.
     var length = withoutColors(buffer.toString()).length;
-    if (truncate) message = utils.truncate(message, _lineLength - length);
+    if (truncate) message = utils.truncate(message, lineLength - length);
     buffer.write(message);
     buffer.write(_noColor);
 
     // Pad the rest of the line so that it looks erased.
-    buffer.write(' ' * (_lineLength - withoutColors(buffer.toString()).length));
+    buffer.write(' ' * (lineLength - withoutColors(buffer.toString()).length));
     stdout.write(buffer.toString());
 
     _printedNewline = false;

lib/src/runner/reporter/expanded.dart

@@ -14,11 +14,6 @@ import '../load_exception.dart';
 import '../load_suite.dart';
 import '../reporter.dart';
 
-/// The maximum console line length.
-///
-/// Lines longer than this will be cropped.
-const _lineLength = 100;
-
 /// A reporter that prints each test on its own line.
 ///
 /// This is currently used in place of [CompactReporter] by `lib/test.dart`,
@@ -238,10 +233,9 @@ class ExpandedReporter implements Reporter {
 
   /// Prints a line representing the current state of the tests.
   ///
-  /// [message] goes after the progress report, and may be truncated to fit the
-  /// entire line within [_lineLength]. If [color] is passed, it's used as the
-  /// color for [message]. If [suffix] is passed, it's added to the end of
-  /// [message].
+  /// [message] goes after the progress report. If [color] is passed, it's used
+  /// as the color for [message]. If [suffix] is passed, it's added to the end
+  /// of [message].
   void _progressLine(String message, {String color, String suffix}) {
     // Print nothing if nothing has changed since the last progress line.
     if (_engine.passed.length == _lastProgressPassed &&

lib/src/util/io.dart

@@ -18,6 +18,23 @@ const _newline = 0xA;
 /// The ASCII code for a carriage return character.
 const _carriageReturn = 0xD;
 
+/// The default line length for output when there isn't a terminal attached to
+/// stdout.
+const _defaultLineLength = 200;
+
+/// The maximum line length for output.
+final int lineLength = () {
+  try {
+    return stdout.terminalColumns;
+  } on UnsupportedError {
+    // This can throw an [UnsupportedError] if we're running in a JS context
+    // where `dart:io` is unavaiable.
+    return _defaultLineLength;
+  } on StdoutException {
+    return _defaultLineLength;
+  }
+}();
+
 /// The root directory of the Dart SDK.
 final String sdkDir = p.dirname(p.dirname(Platform.resolvedExecutable));
 
@@ -103,6 +120,36 @@ Stream<List<int>> sanitizeForWindows(Stream<List<int>> input) {
   });
 }
 
+/// Wraps [text] so that it fits within [lineLength].
+///
+/// This preserves existing newlines and doesn't consider terminal color escapes
+/// part of a word's length. It only splits words on spaces, not on other sorts
+/// of whitespace.
+String wordWrap(String text) {
+  return text.split("\n").map((originalLine) {
+    var buffer = new StringBuffer();
+    var lengthSoFar = 0;
+    for (var word in originalLine.split(" ")) {
+      var wordLength = withoutColors(word).length;
+      if (wordLength > lineLength) {
+        if (lengthSoFar != 0) buffer.writeln();
+        buffer.writeln(word);
+      } else if (lengthSoFar == 0) {
+        buffer.write(word);
+        lengthSoFar = wordLength;
+      } else if (lengthSoFar + 1 + wordLength > lineLength) {
+        buffer.writeln();
+        buffer.write(word);
+        lengthSoFar = wordLength;
+      } else {
+        buffer.write(" $word");
+        lengthSoFar += 1 + wordLength;
+      }
+    }
+    return buffer.toString();
+  }).join("\n");
+}
+
 /// Print a warning containing [message].
 ///
 /// This automatically wraps lines if they get too long. If [color] is passed,

lib/src/utils.dart

@@ -17,9 +17,6 @@ import 'package:term_glyph/term_glyph.dart' as glyph;
 import 'backend/invoker.dart';
 import 'backend/operating_system.dart';
 
-/// The maximum console line length.
-const _lineLength = 100;
-
 /// A typedef for a possibly-asynchronous function.
 ///
 /// The return type should only ever by [Future] or void.
@@ -140,37 +137,6 @@ String pluralize(String name, int number, {String plural}) {
 /// whether its first letter is a vowel.
 String a(String noun) => noun.startsWith(_vowel) ? "an $noun" : "a $noun";
 
-/// Wraps [text] so that it fits within [lineLength], which defaults to 100
-/// characters.
-///
-/// This preserves existing newlines and doesn't consider terminal color escapes
-/// part of a word's length.
-String wordWrap(String text, {int lineLength}) {
-  if (lineLength == null) lineLength = _lineLength;
-  return text.split("\n").map((originalLine) {
-    var buffer = new StringBuffer();
-    var lengthSoFar = 0;
-    for (var word in originalLine.split(" ")) {
-      var wordLength = withoutColors(word).length;
-      if (wordLength > lineLength) {
-        if (lengthSoFar != 0) buffer.writeln();
-        buffer.writeln(word);
-      } else if (lengthSoFar == 0) {
-        buffer.write(word);
-        lengthSoFar = wordLength;
-      } else if (lengthSoFar + 1 + wordLength > lineLength) {
-        buffer.writeln();
-        buffer.write(word);
-        lengthSoFar = wordLength;
-      } else {
-        buffer.write(" $word");
-        lengthSoFar += 1 + wordLength;
-      }
-    }
-    return buffer.toString();
-  }).join("\n");
-}
-
 /// A regular expression matching terminal color codes.
 final _colorCode = new RegExp('\u001b\\[[0-9;]+m');
 

pubspec.yaml

@@ -1,5 +1,5 @@
 name: test
-version: 0.12.26+1
+version: 0.12.27-dev
 author: Dart Team <[email protected]>
 description: A library for writing dart unit tests.
 homepage: https://github.com/dart-lang/test

test/runner/compact_reporter_test.dart

@@ -149,13 +149,15 @@ void main() {
     return _expectReport("""
         test(
            'really gosh dang long test name. Even longer than that. No, yet '
-               'longer. A little more... okay, that should do it.',
+               'longer. Even more. We have to get to at least 200 characters. '
+               'I know that seems like a lot, but I believe in you. A little '
+               'more... okay, that should do it.',
            () => throw new TestFailure('oh no'));""", """
         +0: loading test.dart
-        +0: really ... longer than that. No, yet longer. A little more... okay, that should do it.
-        +0 -1: really gosh dang long test name. Even longer than that. No, yet longer. A little more... okay, that should do it. [E]
+        +0: really ... than that. No, yet longer. Even more. We have to get to at least 200 characters. I know that seems like a lot, but I believe in you. A little more... okay, that should do it.
+        +0 -1: really gosh dang long test name. Even longer than that. No, yet longer. Even more. We have to get to at least 200 characters. I know that seems like a lot, but I believe in you. A little more... okay, that should do it. [E]
           oh no
-          test.dart 9:18  main.<fn>
+          test.dart 11:18  main.<fn>
 
 
         +0 -1: Some tests failed.""");
@@ -268,14 +270,16 @@ void main() {
       return _expectReport("""
           test(
              'really gosh dang long test name. Even longer than that. No, yet '
-                 'longer. A little more... okay, that should do it.',
+                 'longer. Even more. We have to get to at least 200 '
+                 'characters. I know that seems like a lot, but I believe in '
+                 'you. A little more... okay, that should do it.',
              () => print('hello'));""", """
           +0: loading test.dart
-          +0: really ... longer than that. No, yet longer. A little more... okay, that should do it.
-          +0: really gosh dang long test name. Even longer than that. No, yet longer. A little more... okay, that should do it.
+          +0: really ... than that. No, yet longer. Even more. We have to get to at least 200 characters. I know that seems like a lot, but I believe in you. A little more... okay, that should do it.
+          +0: really gosh dang long test name. Even longer than that. No, yet longer. Even more. We have to get to at least 200 characters. I know that seems like a lot, but I believe in you. A little more... okay, that should do it.
           hello
 
-          +1: really ... longer than that. No, yet longer. A little more... okay, that should do it.
+          +1: really ... than that. No, yet longer. Even more. We have to get to at least 200 characters. I know that seems like a lot, but I believe in you. A little more... okay, that should do it.
           +1: All tests passed!""");
     });
 

test/runner/configuration/top_level_test.dart

@@ -76,9 +76,9 @@ void main() {
           "",
           startsWith("Observatory URL: "),
           startsWith("Remote debugger URL: "),
-          "The test runner is paused. Open the remote debugger or the Observatory "
-              "and set breakpoints. Once",
-          "you're finished, return to this terminal and press Enter."
+          "The test runner is paused. Open the remote debugger or the "
+              "Observatory and set breakpoints. Once you're finished, return "
+              "to this terminal and press Enter."
         ]));
 
     var nextLineFired = false;

test/runner/pause_after_load_test.dart

@@ -44,8 +44,8 @@ void main() {
         emitsThrough(emitsInOrder([
           startsWith("Observatory URL: "),
           "The test runner is paused. Open the dev console in Dartium or the "
-              "Observatory and set breakpoints.",
-          "Once you're finished, return to this terminal and press Enter."
+              "Observatory and set breakpoints. Once you're finished, return "
+              "to this terminal and press Enter."
         ])));
 
     var nextLineFired = false;
@@ -67,8 +67,8 @@ void main() {
         emitsThrough(emitsInOrder([
           startsWith("Observatory URL: "),
           "The test runner is paused. Open the dev console in Dartium or the "
-              "Observatory and set breakpoints.",
-          "Once you're finished, return to this terminal and press Enter."
+              "Observatory and set breakpoints. Once you're finished, return "
+              "to this terminal and press Enter."
         ])));
 
     nextLineFired = false;
@@ -108,8 +108,8 @@ void main() {
         emitsThrough(emitsInOrder([
           startsWith("Observatory URL: "),
           "The test runner is paused. Open the dev console in Dartium or the "
-              "Observatory and set breakpoints.",
-          "Once you're finished, return to this terminal and press Enter."
+              "Observatory and set breakpoints. Once you're finished, return "
+              "to this terminal and press Enter."
         ])));
 
     var nextLineFired = false;
@@ -130,8 +130,8 @@ void main() {
         test.stdout,
         emitsThrough(emitsInOrder([
           "The test runner is paused. Open the dev console in Chrome and set "
-              "breakpoints. Once you're finished,",
-          "return to this terminal and press Enter."
+              "breakpoints. Once you're finished, return to this terminal and "
+              "press Enter."
         ])));
 
     nextLineFired = false;
@@ -191,8 +191,8 @@ void main() {
         emitsThrough(emitsInOrder([
           startsWith("Observatory URL: "),
           "The test runner is paused. Open the dev console in Dartium or the "
-              "Observatory and set breakpoints.",
-          "Once you're finished, return to this terminal and press Enter."
+              "Observatory and set breakpoints. Once you're finished, return "
+              "to this terminal and press Enter."
         ])));
 
     var nextLineFired = false;
@@ -234,8 +234,8 @@ void main() {
         emitsThrough(emitsInOrder([
           startsWith("Observatory URL: "),
           "The test runner is paused. Open the dev console in Dartium or the "
-              "Observatory and set breakpoints.",
-          "Once you're finished, return to this terminal and press Enter."
+              "Observatory and set breakpoints. Once you're finished, return "
+              "to this terminal and press Enter."
         ])));
 
     test.signal(ProcessSignal.SIGTERM);
@@ -266,8 +266,8 @@ void main() {
         emitsThrough(emitsInOrder([
           startsWith("Observatory URL: "),
           "The test runner is paused. Open the dev console in Dartium or the "
-              "Observatory and set breakpoints.",
-          "Once you're finished, return to this terminal and press Enter."
+              "Observatory and set breakpoints. Once you're finished, return "
+              "to this terminal and press Enter."
         ])));
 
     var nextLineFired = false;
@@ -309,8 +309,8 @@ void main() {
         emitsThrough(emitsInOrder([
           startsWith("Observatory URL: "),
           "The test runner is paused. Open the dev console in Dartium or the "
-              "Observatory and set breakpoints.",
-          "Once you're finished, return to this terminal and press Enter."
+              "Observatory and set breakpoints. Once you're finished, return "
+              "to this terminal and press Enter."
         ])));
 
     var nextLineFired = false;