Add a number of convenience methods to test_pub.

Add a number of convenience methods to test_pub.

This changelist has two goals. The first is to simply clean up pub_test by
factoring out repeated patterns, removing the use of raw YAML, and making the
commands more semantic. The second goal is to set the stage for the use of
ephemeral ports for the mock package server, which will allow multiple instances
of the tests to be run simultaneously.

Committed: https://code.google.com/p/dart/source/detail?r=11261

[Bob Nystrom, 2012-08-22 16:33:09]

This is really nice. LGTM.

One thing we should talk about at some point: Unit test code tends to be "flat"
in that it tends to be more redundant but simpler so that it's self evident that
the test code itself is correct. As we move towards the test code being more
sophisticated (and less redundant!), we'll start running a greater chance of
having bugs in the test code itself.

Crazy as it sounds, we'll probably want to test test_pub.dart too before too
long.

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
File utils/tests/pub/test_pub.dart (right):

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
utils/tests/pub/test_pub.dart:133: pubspecs.forEach((spec) {
This is mostly a matter of taste, but how about using a regular for-in loop
here? I tend to only use forEach() for maps, or if the body actually needs to be
a first class function. Otherwise, especially with multi-line bodies, I think a
regular loop is a bit easier to read and more familiar to most programmers.

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
utils/tests/pub/test_pub.dart:164: * Returns a file named `pubspec.yaml` with
the given YAML-serialized
I find the "Returns a" and "Returns the" (especially the latter) a bit confusing
to read. For example "Returns the `packages/` directory containing all the given
[packages]" makes it sound like the packages/ dir already exists and the
function just finds it.

How about "Describes a" instead?

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
utils/tests/pub/test_pub.dart:954: * Completes with the fully resolved
structure.
This is very cool, although it pains me to realize Dart's async model means
we're apparently very slowly reinventing Haskell, one thunk at a time.

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
utils/tests/pub/test_pub.dart:957: if (object is Future) return
object.chain(_awaitObject);
Took me a while to realize what this case was for. Add:

// Unroll nested futures.

[nweiz, 2012-08-23 18:09:08]

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
File utils/tests/pub/test_pub.dart (right):

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
utils/tests/pub/test_pub.dart:133: pubspecs.forEach((spec) {
On 2012/08/22 16:33:09, Bob Nystrom wrote:
> This is mostly a matter of taste, but how about using a regular for-in loop
> here? I tend to only use forEach() for maps, or if the body actually needs to
be
> a first class function. Otherwise, especially with multi-line bodies, I think
a
> regular loop is a bit easier to read and more familiar to most programmers.

Done.

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
utils/tests/pub/test_pub.dart:164: * Returns a file named `pubspec.yaml` with
the given YAML-serialized
On 2012/08/22 16:33:09, Bob Nystrom wrote:
> I find the "Returns a" and "Returns the" (especially the latter) a bit
confusing
> to read. For example "Returns the `packages/` directory containing all the
given
> [packages]" makes it sound like the packages/ dir already exists and the
> function just finds it.
> 
> How about "Describes a" instead?

Done.

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
utils/tests/pub/test_pub.dart:954: * Completes with the fully resolved
structure.
On 2012/08/22 16:33:09, Bob Nystrom wrote:
> This is very cool, although it pains me to realize Dart's async model means
> we're apparently very slowly reinventing Haskell, one thunk at a time.

Yyyyep.

https://chromiumcodereview.appspot.com/10871008/diff/1/utils/tests/pub/test_p...
utils/tests/pub/test_pub.dart:957: if (object is Future) return
object.chain(_awaitObject);
On 2012/08/22 16:33:09, Bob Nystrom wrote:
> Took me a while to realize what this case was for. Add:
> 
> // Unroll nested futures.

Done.