Allow DirectoryDescriptor.load to load a file next to a directory.

Allow DirectoryDescriptor.load to load a file next to a directory.

This mkaes it easier to model servers using descriptors.

R=rnystrom@google.com

Committed: https://code.google.com/p/dart/source/detail?r=23607

[Bob Nystrom, 2013-06-04 15:45:53]

Some nits but LGTM. I really like this change. I was never a huge fan of
everything having open() and load() when many just threw exceptions.

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/lib/src/de...
File pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart (right):

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/lib/src/de...
pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart:62: throw "Can't
load absolute path '$pathToLoad'.";
While you're at it, make this an ArgumentError.

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/lib/src/de...
pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart:67: throw "Can't
load '$pathToLoad' from within '$name'.";
And this.

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/lib/src/de...
pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart:74: entry is
LoadableDescriptor);
Is DirectoryDescriptor the only thing that implements LoadableDescriptor? If so,
you could get rid of that interface and check for DirectoryDescriptor
explicitly.

Or, if you expect stuff like TarDescriptor to be "directory-like", leave this
as-is.

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/test/descr...
File pkg/scheduled_test/test/descriptor/directory_test.dart (right):

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/test/descr...
pkg/scheduled_test/test/descriptor/directory_test.dart:358:
expectTestsPass("directory().load() loads a file next to a directory with "
"directory" -> "subdirectory"

[nweiz, 2013-06-04 18:26:45]

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/lib/src/de...
File pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart (right):

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/lib/src/de...
pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart:62: throw "Can't
load absolute path '$pathToLoad'.";
On 2013/06/04 15:45:53, Bob Nystrom wrote:
> While you're at it, make this an ArgumentError.

Done.

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/lib/src/de...
pkg/scheduled_test/lib/src/descriptor/directory_descriptor.dart:74: entry is
LoadableDescriptor);
On 2013/06/04 15:45:53, Bob Nystrom wrote:
> Is DirectoryDescriptor the only thing that implements LoadableDescriptor? If
so,
> you could get rid of that interface and check for DirectoryDescriptor
> explicitly.
> 
> Or, if you expect stuff like TarDescriptor to be "directory-like", leave this
> as-is.

I want to support directory-like descriptors that don't necessarily inherit from
DirectoryDescriptor.

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/test/descr...
File pkg/scheduled_test/test/descriptor/directory_test.dart (right):

https://codereview.chromium.org/15682008/diff/1/pkg/scheduled_test/test/descr...
pkg/scheduled_test/test/descriptor/directory_test.dart:358:
expectTestsPass("directory().load() loads a file next to a directory with "
On 2013/06/04 15:45:53, Bob Nystrom wrote:
> "directory" -> "subdirectory"

Done.

[nweiz, 2013-06-04 18:30:56]

Committed patchset #2 manually as r23607 (presubmit successful).