Unify process_wrapper and process to have the same api and logging styles.

Also add unchecked runSync wrapper and use it in places where command failures don’t matter.

packages/flutter_tools/lib/src/device.dart

@@ -12,7 +12,7 @@ import 'package:logging/logging.dart';
 import 'package:path/path.dart' as path;
 
 import 'application_package.dart';
-import 'process_wrapper.dart';
+import 'process.dart';
 
 final Logger _logging = new Logger('sky_tools.device');
 
@@ -299,24 +299,20 @@ class AndroidDevice extends _Device {
 
   bool stop(AndroidApk apk) {
     // Turn off reverse port forwarding
-    try {
-      runCheckedSync([adbPath, 'reverse', '--remove', 'tcp:$_serverPort']);
-    } catch (e) {}
+    runSync([adbPath, 'reverse', '--remove', 'tcp:$_serverPort']);
     // Stop the app
-    runCheckedSync([adbPath, 'shell', 'am', 'force-stop', apk.appPackageID]);
+    runSync([adbPath, 'shell', 'am', 'force-stop', apk.appPackageID]);
     // Kill the server
-    try {
-      if (Platform.isMacOS) {
-        String pid = runCheckedSync(['lsof', '-i', ':$_serverPort', '-t']);
-        // Killing a pid with a shell command from within dart is hard,
-        // so use a library command, but it's still nice to give the
-        // equivalent command when doing verbose logging.
-        _logging.info('kill $pid');
-        Process.killPid(int.parse(pid));
-      } else {
-        runCheckedSync(['fuser', '-k', '$_serverPort/tcp']);
-      }
-    } catch (e) {}
+    if (Platform.isMacOS) {
+      String pid = runSync(['lsof', '-i', ':$_serverPort', '-t']);
+      // Killing a pid with a shell command from within dart is hard,
+      // so use a library command, but it's still nice to give the
+      // equivalent command when doing verbose logging.
+      _logging.info('kill $pid');
+      Process.killPid(int.parse(pid));
+    } else {
+      runSync(['fuser', '-k', '$_serverPort/tcp']);
+    }
 
     return true;
   }

packages/flutter_tools/lib/src/process.dart

@@ -12,10 +12,12 @@ import 'package:logging/logging.dart';
 
 final Logger _logging = new Logger('sky_tools.process');
 
-// This runs the command and streams stdout/stderr from the child process to this process' stdout/stderr.
-Future<int> runCommandAndStreamOutput(String command, List<String> args) async {
-  _logging.fine("Starting ${command} with args: ${args}");
-  Process proc = await Process.start(command, args);
+/// This runs the command and streams stdout/stderr from the child process to
+/// this process' stdout/stderr.
+Future<int> runCommandAndStreamOutput(List<String> cmd) async {
+  _logging.info(cmd.join(' '));
+  Process proc =
+      await Process.start(cmd[0], cmd.getRange(1, cmd.length).toList());
   proc.stdout.transform(UTF8.decoder).listen((data) {
     stdout.write(data);
   });
@@ -24,3 +26,31 @@ Future<int> runCommandAndStreamOutput(String command, List<String> args) async {
   });
   return proc.exitCode;
 }
+
+/// Run cmd and return stdout.
+/// Throws an error if cmd exits with a non-zero value.
+String runCheckedSync(List<String> cmd) =>
+    _runWithLoggingSync(cmd, checked: true);
+
+/// Run cmd and return stdout.
+String runSync(List<String> cmd) => _runWithLoggingSync(cmd);
+
+String _runWithLoggingSync(List<String> cmd, {bool checked: false}) {
+  _logging.info(cmd.join(' '));
+  ProcessResult results =
+      Process.runSync(cmd[0], cmd.getRange(1, cmd.length).toList());
+  if (results.exitCode != 0) {
+    String errorDescription = 'Error code ${results.exitCode} '
+        'returned when attempting to run command: ${cmd.join(' ')}';
+    _logging.fine(errorDescription);
+    if (results.stderr.length > 0) {
+      _logging.info('Errors logged: ${results.stderr.trim()}');
+    }
+
+    if (checked) {
+      throw errorDescription;
+    }
+  }
+  _logging.fine(results.stdout.trim());
+  return results.stdout;
+}

packages/flutter_tools/lib/src/process_wrapper.dart

-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-library sky_tools.process_wrapper;
-
-import 'dart:io';
-import 'package:logging/logging.dart';
-
-final Logger _logging = new Logger('sky_tools.process_wrapper');
-String runCheckedSync(List<String> cmd) {
-  _logging.info(cmd.join(' '));
-  ProcessResult results =
-      Process.runSync(cmd[0], cmd.getRange(1, cmd.length).toList());
-  if (results.exitCode != 0) {
-    if (results.stderr.length > 0) {
-      _logging.info('Errors logged: ' + results.stderr);
-    }
-    throw 'Error code ' +
-        results.exitCode.toString() +
-        ' returned when attempting to run command: ' +
-        cmd.join(' ');
-  }
-  _logging.fine(results.stdout.trim());
-  return results.stdout;
-}

packages/flutter_tools/lib/src/run_mojo.dart

@@ -45,7 +45,8 @@ class RunMojoCommand extends Command {
     String appName = path.basename(appPath);
     String appDir = path.dirname(appPath);
     String buildFlag = mojoConfig == _MojoConfig.Debug ? '--debug' : '--release';
-    List<String> args = [
+    List<String> cmd = [
+      command,
       '--android',
       buildFlag,
       'http://app/$appName',
@@ -54,25 +55,26 @@ class RunMojoCommand extends Command {
       '--url-mappings=mojo:sky_viewer=http://sky_viewer/sky_viewer.mojo',
     ];
     if (_logging.level <= Level.INFO) {
-      args.add('--verbose');
+      cmd.add('--verbose');
       if (_logging.level <= Level.FINE) {
-        args.add('--verbose');
+        cmd.add('--verbose');
       }
     }
-    args.addAll(additionalArgs);
-    return runCommandAndStreamOutput(command, args);
+    cmd.addAll(additionalArgs);
+    return runCommandAndStreamOutput(cmd);
   }
 
   Future<int> _runLinux(String mojoPath, _MojoConfig mojoConfig, String appPath, List<String> additionalArgs) async {
     String viewerPath = await _makePathAbsolute(await ArtifactStore.getPath(Artifact.SkyViewerMojo));
     String mojoBuildType = mojoConfig == _MojoConfig.Debug ? 'Debug' : 'Release';
     String mojoShellPath = await _makePathAbsolute(path.join(mojoPath, 'out', mojoBuildType, 'mojo_shell'));
-    List<String> args = [
+    List<String> cmd = [
+      mojoShellPath,
       'file://${appPath}',
       '--url-mappings=mojo:sky_viewer=file://${viewerPath}'
     ];
-    args.addAll(additionalArgs);
-    return runCommandAndStreamOutput(mojoShellPath, args);
+    cmd.addAll(additionalArgs);
+    return runCommandAndStreamOutput(cmd);
   }
 
   @override