Improve error output, mention webdev, etc

Author: kevmoo

webdev/bin/webdev.dart

@@ -10,6 +10,7 @@ import 'package:args/command_runner.dart';
 import 'package:io/ansi.dart';
 import 'package:io/io.dart';
 import 'package:webdev/src/webdev_command_runner.dart';
+import 'package:webdev/src/util.dart';
 
 Future main(List<String> args) async {
   try {
@@ -19,26 +20,28 @@ Future main(List<String> args) async {
     print(' ');
     print(e.usage);
     exitCode = ExitCode.usage.code;
+  } on FileSystemException catch (e) {
+    print(yellow.wrap('$_boldApp could not run in the current directory.'));
+    print(e.message);
+    if (e.path != null) {
+      print('  ${e.path}');
+    }
+    exitCode = ExitCode.config.code;
   } on PackageException catch (e) {
-    print(yellow.wrap('Could not run in the current directory.'));
+    print(yellow.wrap('$_boldApp could not run for this project.'));
     for (var detail in e.details) {
-      print(detail.error);
+      print(yellow.wrap(detail.error));
       if (detail.description != null) {
-        print('  ${detail.description}');
+        print(detail.description);
       }
     }
 
-    exitCode = ExitCode.config.code;
-  } on FileSystemException catch (e) {
-    print(yellow.wrap('Could not run in the current directory.'));
-    print(e.message);
-    if (e.path != null) {
-      print('  ${e.path}');
-    }
     exitCode = ExitCode.config.code;
   } on IsolateSpawnException catch (e) {
-    print(red.wrap('An unexpected exception has occurred.'));
+    print(red.wrap('$_boldApp failed with an unexpected exception.'));
     print(e.message);
     exitCode = ExitCode.software.code;
   }
 }
+
+String get _boldApp => styleBold.wrap(appName);

webdev/lib/src/pubspec.dart

@@ -25,13 +25,14 @@ class PackageExceptionDetails {
   static const noPubspecLock = const PackageExceptionDetails._(
       '`pubspec.lock` does not exist.',
       description:
-          'Run `webdev` in a Dart package directory. Run `pub get` first.');
+          'Run `$appName` in a Dart package directory. Run `pub get` first.');
 
-  static const noBuildRunnerDep = const PackageExceptionDetails._(
-      'A dependency on `build_runner` was not found.',
-      description:
-          'You must have a dependency on `build_runner` in `pubspec.yaml`. '
-          'It can be in either `dependencies` or `dev_dependencies`.');
+  static final noBuildRunnerDep = new PackageExceptionDetails._(
+      'You must have a dependency on `build_runner` in `pubspec.yaml`.',
+      description: '''
+# pubspec.yaml
+dev_dependencies:
+  build_runner: $supportedBuildRunnerVersionConstraint''');
 
   @override
   String toString() => [error, description].join('\n');
@@ -81,9 +82,9 @@ Future checkPubspecLock() async {
 
       var version = buildRunner['version'] as String;
       var buildRunnerVersion = new Version.parse(version);
-      if (!supportedBuildRunnerVersionRange.allows(buildRunnerVersion)) {
+      if (!supportedBuildRunnerVersionConstraint.allows(buildRunnerVersion)) {
         var error = 'The `build_runner` version – $buildRunnerVersion – is not '
-            'within the supported range – $supportedBuildRunnerVersionRange.';
+            'within the allowed constraint – $supportedBuildRunnerVersionConstraint.';
         issues.add(new PackageExceptionDetails._(error));
       }
     } else {

webdev/lib/src/util.dart

@@ -7,11 +7,10 @@ import 'dart:io';
 import 'package:path/path.dart' as p;
 import 'package:pub_semver/pub_semver.dart';
 
-final supportedBuildRunnerVersionRange = new VersionRange(
-    min: new Version(0, 8, 0),
-    includeMin: true,
-    max: new Version(0, 9, 0),
-    includeMax: false);
+const appName = 'webdev';
+
+final supportedBuildRunnerVersionConstraint =
+    new VersionConstraint.parse('^0.8.0');
 
 /// The path to the root directory of the SDK.
 final String _sdkDir = (() {

webdev/lib/src/webdev_command_runner.dart

@@ -8,12 +8,13 @@ import 'package:args/command_runner.dart';
 
 import 'command/build_command.dart';
 import 'command/serve_command.dart';
+import 'util.dart';
 
 export 'pubspec.dart' show PackageException;
 
 Future<int> run(List<String> args) async {
   var runner =
-      new CommandRunner<int>('webdev', 'A tool to develop Dart web projects.')
+      new CommandRunner<int>(appName, 'A tool to develop Dart web projects.')
         ..addCommand(new BuildCommand())
         ..addCommand(new ServeCommand());
 

webdev/test/integration_test.dart

@@ -46,8 +46,8 @@ void main() {
     var process = await _runWebDev(['build']);
     var output = (await process.stdoutStream().join('\n')).trim();
 
-    expect(output, contains(r'''Could not run in the current directory.
-A dependency on `build_runner` was not found.'''));
+    expect(output, contains(r'''webdev could not run for this project.
+You must have a dependency on `build_runner` in `pubspec.yaml`.'''));
     await process.shouldExit(78);
   });
 
@@ -66,11 +66,11 @@ name: sample
         var process = await _runWebDev(['build'], workingDirectory: d.sandbox);
 
         await expectLater(
-            process.stdout, emits('Could not run in the current directory.'));
+            process.stdout, emits('webdev could not run for this project.'));
         await expectLater(
             process.stdout,
             emits('The `build_runner` version – $version – '
-                'is not within the supported range – >=0.8.0 <0.9.0.'));
+                'is not within the allowed constraint – ^0.8.0.'));
         await process.shouldExit(78);
       });
     }
@@ -81,7 +81,7 @@ name: sample
 
     var output = await process.stdoutStream().join('\n');
 
-    expect(output, contains('Could not run in the current directory.'));
+    expect(output, contains('webdev could not run for this project.'));
     expect(output, contains('Could not find a file named "pubspec.yaml"'));
     await process.shouldExit(78);
   });
@@ -95,7 +95,7 @@ name: sample
 
     var output = await process.stdoutStream().join('\n');
 
-    expect(output, contains('Could not run in the current directory.'));
+    expect(output, contains('webdev could not run for this project.'));
     expect(output,
         contains('No pubspec.lock file found, please run "pub get" first.'));
     await process.shouldExit(78);
@@ -112,7 +112,7 @@ name: sample
 
     var output = await process.stdoutStream().join('\n');
 
-    expect(output, contains('Could not run in the current directory.'));
+    expect(output, contains('webdev could not run for this project.'));
     expect(output,
         contains('No .packages file found, please run "pub get" first.'));
     await process.shouldExit(78);
@@ -131,7 +131,7 @@ name: sample
 
     var output = await process.stdoutStream().join('\n');
 
-    expect(output, contains('An unexpected exception has occurred.'));
+    expect(output, contains('webdev failed with an unexpected exception.'));
 
     // The isolate will fail - broken .packages file
     expect(output, contains('Unable to spawn isolate'));
@@ -156,7 +156,7 @@ dependencies:
 
     var output = await process.stdoutStream().join('\n');
 
-    expect(output, contains('Could not run in the current directory.'));
+    expect(output, contains('webdev could not run for this project.'));
     expect(
         output,
         contains(