Add Process.shell and Process.runShell.

sdk/lib/io/process.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.io;
 
 // TODO(ager): The only reason for this class is that we
 // cannot patch a top-level at this point.
 class _ProcessUtils {
   external static void _exit(int status);
@@ skipping 80 matching lines @@
    * An optional [ProcessOptions] object can be passed to specify
    * options other than the executable and the arguments.
    *
    * Returns a [:Future<ProcessResult>:] that completes with the
    * result of running the process, i.e., exit code, standard out and
    * standard in.
    */
   external static Future<ProcessResult> run(String executable,
                                             List<String> arguments,
                                             [ProcessOptions options]);
 

[Søren Gjesse, 2013/05/17 14:48:56]

This method needs a comment.

Should there be a way of specifying the actual shell command to use? Or should
we just document the search strategy used. See comments below.

[Anders Johnsen, 2013/05/22 07:45:51]

Done.

+  static Future<ProcessResult> runShell(String executable,
+                                        List<String> arguments,
+                                        [ProcessOptions options])
+      => run(_getShellCommand(),
+             _getShellArguments(executable, arguments),
+             options);
+

[Søren Gjesse, 2013/05/17 14:48:56]

I am not sure we should have both runShell and shell. The do almost the same. To
be consistent I think when something returns ProcessResult it should be called
runXXX.

[Anders Johnsen, 2013/05/22 07:45:51]

Done.

+  static Future<ProcessResult> shell(String command,

[kustermann, 2013/05/21 07:50:00]

What is this method doing?

[Anders Johnsen, 2013/05/22 07:45:51]

It's gone.

+                                     [ProcessOptions options])
+      => run(_getShellCommand(),
+             _getShellArguments(command, []),
+             options);
+
+  static String _getShellCommand() {

[Søren Gjesse, 2013/05/17 14:48:56]

Maybe we should do more extensive search of the shell to use.

[Anders Johnsen, 2013/05/22 07:45:51]

Done.

+    if (Platform.operatingSystem == 'windows') {
+      return "cmd";

[Søren Gjesse, 2013/05/17 14:48:56]

Should we lookup %COMSPEC% in the Windows environment? Should it default to
"%WINDIR%\system32\cmd.exe"?

[Anders Johnsen, 2013/05/22 07:45:51]

Done.

+    }
+    return "sh";

[Søren Gjesse, 2013/05/17 14:48:56]

Should we lookup $SHELL in the environment? Should it default to /bin/sh?

[ricow1, 2013/05/21 07:26:34]

I don't really care what it defaults to, but I do think we should lookup $SHELL,
I would assume that bash is used if SHELL is set to it

[kustermann, 2013/05/21 07:50:00]

The issue here is that different shells might interpret their arguments
differently (zsh, bash, csh ..).
As soon as we do '-c' we assume that the shell supports it. In addition to that,
we assume that all shells interpret the arguments the same way (e.g. is "ls
**/*dart" supported?).
IMHO the safest way to do it is "/bin/sh -c"

[Anders Johnsen, 2013/05/22 07:45:51]

Done.

+  }
+
+  static List<String> _getShellArguments(String executable,
+                                         List<String> arguments) {
+    List<String> shellArguments = [];
+    if (Platform.operatingSystem == 'windows') {
+      shellArguments.add("/k");
+    } else {
+      shellArguments.add("-c");
+    }
+    var commandLine = executable;
+    for (var arg in arguments) {
+      arg = arg.replaceAll("'", "'\"'\"'");

[Lasse Reichstein Nielsen, 2013/05/21 07:31:51]

You could use a multiline string here:
  """'"'"'"""
Not confusing at all :)

[Anders Johnsen, 2013/05/22 07:45:51]

Hehe, I prefer not ;)

+      commandLine = "$commandLine '$arg'";

[Lasse Reichstein Nielsen, 2013/05/21 07:13:42]

Quadratic time string concatenation. Use a StringBuffer.

[Anders Johnsen, 2013/05/22 07:45:51]

Done.

+    }
+    shellArguments.add(commandLine);
+    return shellArguments;
+  }
+
   /**
    * Returns the standard output stream of the process as a [:Stream:].
    *
    * Throws an [UnsupportedError] if the process is
    * non-interactive.
    */
   Stream<List<int>> get stdout;
 
   /**
    * Returns the standard error stream of the process as a [:Stream:].
@@ skipping 178 matching lines @@
   /**
    * Contains the system message for the process exception if any.
    */
   final String message;
 
   /**
    * Contains the OS error code for the process exception if any.
    */
   final int errorCode;
 }