Translate package URIs to resource URIs for diagnostics.

Translate package URIs to resource URIs for diagnostics.

Closes #23699

BUG=http://dartbug.com/23699
R=ahe@google.com, het@google.com

Committed: https://github.com/dart-lang/sdk/commit/76f1fec4f9e9162e8325570255d1ad71ba26e9a2

[Johnni Winther, 2015-06-25 10:06:37]

johnniwinther@google.com changed reviewers:
+ ahe@google.com, het@google.com

[Harry Terkelsen, 2015-06-25 18:24:37]

lgtm

[ahe, 2015-06-26 07:56:06]

This looks like a hack to me. Am I misunderstanding something?

https://codereview.chromium.org/1205373002/diff/1/pkg/compiler/lib/src/apiimp...
File pkg/compiler/lib/src/apiimpl.dart (right):

https://codereview.chromium.org/1205373002/diff/1/pkg/compiler/lib/src/apiimp...
pkg/compiler/lib/src/apiimpl.dart:427: Uri uri = translateUri(null, span.uri);
If I understand this correctly, this may invoke a user-provided plugin for
resolving packages.

This code assumes that plugin is idempotent. However, it might be
extraordinarily complicated to implement a plugin such that it is idempotent,
for example, let's say you provide a plugin which reads an external resource
(for example searches directories, or reads a file). 

Also, what happens if the user-provided plugin throws an exception?

There is one source of truth, and that was established when calling the input
provider. If that URI is preserved and used here, no assumptions about
idempotency are needed.

[Johnni Winther, 2015-06-26 10:15:06]

https://codereview.chromium.org/1205373002/diff/1/pkg/compiler/lib/src/apiimp...
File pkg/compiler/lib/src/apiimpl.dart (right):

https://codereview.chromium.org/1205373002/diff/1/pkg/compiler/lib/src/apiimp...
pkg/compiler/lib/src/apiimpl.dart:427: Uri uri = translateUri(null, span.uri);
On 2015/06/26 07:56:05, ahe wrote:
> If I understand this correctly, this may invoke a user-provided plugin for
> resolving packages.
> 
> This code assumes that plugin is idempotent. However, it might be
> extraordinarily complicated to implement a plugin such that it is idempotent,
> for example, let's say you provide a plugin which reads an external resource
> (for example searches directories, or reads a file). 
> 
> Also, what happens if the user-provided plugin throws an exception?
> 
> There is one source of truth, and that was established when calling the input
> provider. If that URI is preserved and used here, no assumptions about
> idempotency are needed.

Good point. Will cache the resource URIs.

[Johnni Winther, 2015-06-26 17:06:54]

PTAL @ the last patch

https://codereview.chromium.org/1205373002/diff/1/pkg/compiler/lib/src/apiimp...
File pkg/compiler/lib/src/apiimpl.dart (right):

https://codereview.chromium.org/1205373002/diff/1/pkg/compiler/lib/src/apiimp...
pkg/compiler/lib/src/apiimpl.dart:427: Uri uri = translateUri(null, span.uri);
On 2015/06/26 10:15:06, Johnni Winther wrote:
> On 2015/06/26 07:56:05, ahe wrote:
> > If I understand this correctly, this may invoke a user-provided plugin for
> > resolving packages.
> > 
> > This code assumes that plugin is idempotent. However, it might be
> > extraordinarily complicated to implement a plugin such that it is
idempotent,
> > for example, let's say you provide a plugin which reads an external resource
> > (for example searches directories, or reads a file). 
> > 
> > Also, what happens if the user-provided plugin throws an exception?
> > 
> > There is one source of truth, and that was established when calling the
input
> > provider. If that URI is preserved and used here, no assumptions about
> > idempotency are needed.
> 
> Good point. Will cache the resource URIs.

No need for extra caching; it was already in Script.resourceUri.

[Johnni Winther, 2015-06-29 12:41:38]

Ping

[ahe, 2015-06-29 14:04:52]

LGTM!

[Johnni Winther, 2015-06-29 15:13:39]

Committed patchset #2 (id:20001) manually as
76f1fec4f9e9162e8325570255d1ad71ba26e9a2 (presubmit successful).