[kernel] Make fasta call a new constructor on FallThroughError

[kernel] Make fasta call a new constructor on FallThroughError

On a switch fall through error, Fasta currently generates
```
throw new core::FallThroughError::•();
```

which generates the error-message via the VM:
```
'null': Switch case fall-through at line null.
```

This introduces a new constructor taking a url and a linenumber,
which then can give a better error message.

BUG=
R=ahe@google.com

Committed: https://github.com/dart-lang/sdk/commit/be9a3043aaa64ded865b0cacececf4d3a6ddb965

[jensj, 2017-06-19 13:45:51]

jensj@google.com changed reviewers:
+ ahe@google.com

[jensj, 2017-06-19 13:45:51]

I've tried doing something a long the lines of what we discussed per email.
I'm sure there'll be lots of comments :)

[ahe, 2017-06-19 14:33:07]

LGTM with comments.

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/kernel/body_builder.dart (left):

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/kernel/body_builder.dart:2999: Builder constructor =
library.loader.getFallThroughError();
Would you mind removing all the getFallThroughError methods in
pkg/front_end/lib/src/fasta/...?

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/kernel/body_builder.dart (right):

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/kernel/body_builder.dart:43: import
'../messages.dart' as messages;
import '../messages.dart' show getLocationFromUri;

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/kernel/body_builder.dart:3003: charOffset >= 0 ?
messages.getLocationFromUri(uri, charOffset) : null;
Call this unconditionally.

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/messages.dart (right):

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/messages.dart:84: Location getLocationFromUri(Uri
uri, int charOffset) {
if (charOffset == -1) return null;

[jensj, 2017-06-20 11:24:49]

So this file is now different:
pkg/front_end/testcases/rasta/switch_fall_through.dart.direct.expect

do I update it manually or is there some command I can run?

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/kernel/body_builder.dart (left):

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/kernel/body_builder.dart:2999: Builder constructor =
library.loader.getFallThroughError();
On 2017/06/19 14:33:06, ahe wrote:
> Would you mind removing all the getFallThroughError methods in
> pkg/front_end/lib/src/fasta/...?

Done.

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/kernel/body_builder.dart (right):

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/kernel/body_builder.dart:43: import
'../messages.dart' as messages;
On 2017/06/19 14:33:06, ahe wrote:
> import '../messages.dart' show getLocationFromUri;

Done.

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/kernel/body_builder.dart:3003: charOffset >= 0 ?
messages.getLocationFromUri(uri, charOffset) : null;
On 2017/06/19 14:33:06, ahe wrote:
> Call this unconditionally.

Done.

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/messages.dart (right):

https://codereview.chromium.org/2951453002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/messages.dart:84: Location getLocationFromUri(Uri
uri, int charOffset) {
On 2017/06/19 14:33:06, ahe wrote:
> if (charOffset == -1) return null;

Done.

[ahe, 2017-06-20 12:01:54]

On 2017/06/20 11:24:49, jensj wrote:
> So this file is now different:
> pkg/front_end/testcases/rasta/switch_fall_through.dart.direct.expect
> 
> do I update it manually or is there some command I can run?

You can update it manually, or ask the test runner to do it:

  ./pkg/front_end/tool/fasta testing compile/rasta/switch_fall_through
-DupdateExpectations=true

I'll file a bug to document this better.

[ahe, 2017-06-20 12:01:54]

On 2017/06/20 11:24:49, jensj wrote:
> So this file is now different:
> pkg/front_end/testcases/rasta/switch_fall_through.dart.direct.expect
> 
> do I update it manually or is there some command I can run?

You can update it manually, or ask the test runner to do it:

  ./pkg/front_end/tool/fasta testing compile/rasta/switch_fall_through
-DupdateExpectations=true

I'll file a bug to document this better.

[jensj, 2017-06-21 06:41:06]

Description was changed from

==========
[kernel] Make fasta call a new constructor on FallThroughError

On a switch fall through error, Fasta currently generates
```
throw new core::FallThroughError::•();
```

which generates the error-message via the VM:
```
'null': Switch case fall-through at line null.
```

This introduces a new constructor taking a url and a linenumber,
which then can give a better error message.

BUG=
==========

to

==========
[kernel] Make fasta call a new constructor on FallThroughError

On a switch fall through error, Fasta currently generates
```
throw new core::FallThroughError::•();
```

which generates the error-message via the VM:
```
'null': Switch case fall-through at line null.
```

This introduces a new constructor taking a url and a linenumber,
which then can give a better error message.

BUG=
R=ahe@google.com

Committed:
https://github.com/dart-lang/sdk/commit/be9a3043aaa64ded865b0cacececf4d3a6ddb965
==========

[jensj, 2017-06-21 06:41:07]

Committed patchset #2 (id:20001) manually as
be9a3043aaa64ded865b0cacececf4d3a6ddb965 (presubmit successful).