Make the construction of a ProcessResult public

sdk/lib/io/process.dart

Index: sdk/lib/io/process.dart
diff --git a/sdk/lib/io/process.dart b/sdk/lib/io/process.dart
index 2d8ecab3bba56e1471548cbce7d1398f65e6c78f..7f05c4824b655cd31a42dd6ae59da3f81a914a60 100644
--- a/sdk/lib/io/process.dart
+++ b/sdk/lib/io/process.dart
@@ -433,14 +433,14 @@ abstract class Process {
  * [ProcessResult] represents the result of running a non-interactive
  * process started with [:Process.run:].

[Lasse Reichstein Nielsen, 2015/04/07 12:38:44]

[:Process.run:] -> [Process.run] or [Process.runSync].

[Søren Gjesse, 2015/04/07 13:05:35]

Done.

  */
-abstract class ProcessResult {
+class ProcessResult {
   /**
    * Exit code for the process.
    *
    * See [Process.exitCode] for more information in the exit code
    * value.
    */
-  int get exitCode;
+  final int exitCode;
 
   /**
    * Standard output from the process. The value used for the
@@ -448,7 +448,7 @@ abstract class ProcessResult {
    * `null` was used this value is of type `List<int> otherwise it is
    * of type `String`.

[Lasse Reichstein Nielsen, 2015/04/07 12:38:45]

Make ProcessResult generic with the type of this and stderr as parameter.

Then the user can write:

 ProcessResult<String> result = Process.run(..., encoding: UTF8);

and work happily and typed forever after.

[Søren Gjesse, 2015/04/07 13:05:35]

One can specify different encodings for stdout and stderr, so that would require
two different type parameters:

  ProcessResult<String, List<int>> result =
      Process.run(..., stdoutEncoding: UTF8, stderrEncoding: null);

  ProcessResult<String, String> result =
      Process.run(..., stdoutEncoding: UTF8, stderrEncoding: UTF8);

which does not look that nice.

    */
-  get stdout;
+  final stdout;
 
   /**
    * Standard error from the process. The value used for the
@@ -456,12 +456,24 @@ abstract class ProcessResult {
    * `null` was used this value is of type `List<int>
    * otherwise it is of type `String`.
    */
-  get stderr;
+  final stderr;
 
   /**
    * Process id from the process.

[Lasse Reichstein Nielsen, 2015/04/07 12:38:44]

Process id of the process
?

[Søren Gjesse, 2015/04/07 13:05:35]

Done.

    */
-  int get pid;
+  final int pid;
+
+  /**
+   * Construct an instance of [ProcessResult].
+   *
+   * The main use of `ProcessResult is as return value from
+   * `Process.run` and `Process.runSync`. However for some applications

[Lasse Reichstein Nielsen, 2015/04/07 12:38:44]

Comma after "however". Maybe rewrite to something more direct.
Maybe just remove the comment. The use of a class belongs in the class
description, not the constructor. The constructor is completely transparently
named and hardly needs a comment at all.

[Søren Gjesse, 2015/04/07 13:05:35]

I removed the comment.

+   * constructing it directly might be useful.
+   */
+  const ProcessResult(int this.pid,

[Lasse Reichstein Nielsen, 2015/04/07 12:38:44]

Remove the `const` if possible. It makes little-to-no sense that the result of
running a computation can be known at compile time.

If you use it as "const" somewhere, then just make those final and lazily
created instead.

[Søren Gjesse, 2015/04/07 13:05:35]

Done.

+                      int this.exitCode,
+                      this.stdout,
+                      this.stderr);
 }