Use real "package:" imports in pub's plugin-loading code.

Use real "package:" imports in pub's plugin-loading code.

This works by providing the plugin-loading code to pub's barback instance as
assets for a pseudo-package named "$pub".

BUG=17506
R=rnystrom@google.com

Committed: https://code.google.com/p/dart/source/detail?r=34056

[Bob Nystrom, 2014-03-18 18:41:47]

A couple of suggestions, but otherwise very nice. LGTM.

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
File sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart (right):

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart:45: """;
Indentation is a bit unusual here. How about making the """ and the lines in the
string +4 relative to "var code"?

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart:67:
log.fine("looking for uri '$uri'");
If you plan to leave this in, capitalize and punctuate.

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
File sdk/lib/_internal/pub/lib/src/barback/pub_package_provider.dart (right):

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
sdk/lib/_internal/pub/lib/src/barback/pub_package_provider.dart:27: var
nativePath = path.joinAll(path.url.split(id.path));
We do this path dance in lots of places, maybe we should add "nativePath" to
AssetId.

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
sdk/lib/_internal/pub/lib/src/barback/pub_package_provider.dart:35:
assert(components.first == 'lib');
Since this path technically comes from user data, using an assert feels wrong
here. How about throwing an explicit ArgumentError exception?

Also, check for zero-length components.

[nweiz, 2014-03-18 19:55:12]

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
File sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart (right):

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart:45: """;
On 2014/03/18 18:41:47, Bob Nystrom wrote:
> Indentation is a bit unusual here. How about making the """ and the lines in
the
> string +4 relative to "var code"?

I did it this way to make it look like a closure, but sure, done.

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
sdk/lib/_internal/pub/lib/src/barback/load_transformers.dart:67:
log.fine("looking for uri '$uri'");
On 2014/03/18 18:41:47, Bob Nystrom wrote:
> If you plan to leave this in, capitalize and punctuate.

Nope, this should be gone.

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
File sdk/lib/_internal/pub/lib/src/barback/pub_package_provider.dart (right):

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
sdk/lib/_internal/pub/lib/src/barback/pub_package_provider.dart:27: var
nativePath = path.joinAll(path.url.split(id.path));
On 2014/03/18 18:41:47, Bob Nystrom wrote:
> We do this path dance in lots of places, maybe we should add "nativePath" to
> AssetId.

I was actually thinking of letting [path.fromUrl] take a string as well as a
Uri, which I think is more general than adding that to AssetId in particular.

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
sdk/lib/_internal/pub/lib/src/barback/pub_package_provider.dart:35:
assert(components.first == 'lib');
On 2014/03/18 18:41:47, Bob Nystrom wrote:
> Since this path technically comes from user data, using an assert feels wrong
> here. How about throwing an explicit ArgumentError exception?

This doesn't really come from user data -- it comes directly from
[Barback.updateSources], which only we call.

> Also, check for zero-length components.

Done.

[nweiz, 2014-03-18 19:55:41]

Committed patchset #2 manually as r34056 (presubmit successful).

[Bob Nystrom, 2014-03-18 20:05:25]

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
File sdk/lib/_internal/pub/lib/src/barback/pub_package_provider.dart (right):

https://codereview.chromium.org/198053009/diff/1/sdk/lib/_internal/pub/lib/sr...
sdk/lib/_internal/pub/lib/src/barback/pub_package_provider.dart:27: var
nativePath = path.joinAll(path.url.split(id.path));
On 2014/03/18 19:55:12, nweiz wrote:
> On 2014/03/18 18:41:47, Bob Nystrom wrote:
> > We do this path dance in lots of places, maybe we should add "nativePath" to
> > AssetId.
> 
> I was actually thinking of letting [path.fromUrl] take a string as well as a
> Uri, which I think is more general than adding that to AssetId in particular.

SGTM.

[janpech3466, 2014-03-18 23:29:34]

Good