Improve 'length' instance property reference encoding.

Improve 'length' instance property reference encoding.

UnlinkedConstOperation.length is used not only if we can prove that
the target is a StringLiteral (and actually we cannot encode it as a
reference).

The new ReferenceKind.length was added - it is used to encode reference
to the the only instance property we support - 'length'.

R=paulberry@google.com
BUG=

Committed: https://github.com/dart-lang/sdk/commit/e4ab45aa65d9d73185828d00dcfb216b184afad1

[Paul Berry, 2016-01-27 16:48:59]

lgtm

https://codereview.chromium.org/1642483002/diff/1/pkg/analyzer/lib/src/summar...
File pkg/analyzer/lib/src/summary/summarize_const_expr.dart (right):

https://codereview.chromium.org/1642483002/diff/1/pkg/analyzer/lib/src/summar...
pkg/analyzer/lib/src/summary/summarize_const_expr.dart:96: if (expr.target is
StringLiteral && expr.propertyName.name == 'length') {
I think this should be:

    if (expr.target is! PrefixedIdentifier && expr.propertyName.name ==
'length')

That way we correctly handle cases like:

    const x = ('abc' + 'def').length;

and:

    const x = ('abc').length;

https://codereview.chromium.org/1642483002/diff/1/pkg/analyzer/test/src/summa...
File pkg/analyzer/test/src/summary/summary_common.dart (right):

https://codereview.chromium.org/1642483002/diff/1/pkg/analyzer/test/src/summa...
pkg/analyzer/test/src/summary/summary_common.dart:1861:
serializeVariableText('const v = "abc".length;');
Also add tests for the cases I mentioned earlier:

    const x = ('abc' + 'def').length;
    const x = ('abc').length;

[scheglov, 2016-01-27 17:55:10]

https://codereview.chromium.org/1642483002/diff/1/pkg/analyzer/lib/src/summar...
File pkg/analyzer/lib/src/summary/summarize_const_expr.dart (right):

https://codereview.chromium.org/1642483002/diff/1/pkg/analyzer/lib/src/summar...
pkg/analyzer/lib/src/summary/summarize_const_expr.dart:96: if (expr.target is
StringLiteral && expr.propertyName.name == 'length') {
On 2016/01/27 16:48:59, Paul Berry wrote:
> I think this should be:
> 
>     if (expr.target is! PrefixedIdentifier && expr.propertyName.name ==
> 'length')
> 
> That way we correctly handle cases like:
> 
>     const x = ('abc' + 'def').length;
> 
> and:
> 
>     const x = ('abc').length;

Done.

[scheglov, 2016-01-27 17:55:39]

Description was changed from

==========
Improve 'length' instance property reference encoding.

UnlinkedConstOperation.length is used not only if we can prove that
the target is a StringLiteral (and actually we cannot encode it as a
reference).

The new ReferenceKind.length was added - it is used to encode reference
to the the only instance property we support - 'length'.

R=paulberry@google.com
BUG=
==========

to

==========
Improve 'length' instance property reference encoding.

UnlinkedConstOperation.length is used not only if we can prove that
the target is a StringLiteral (and actually we cannot encode it as a
reference).

The new ReferenceKind.length was added - it is used to encode reference
to the the only instance property we support - 'length'.

R=paulberry@google.com
BUG=

Committed:
https://github.com/dart-lang/sdk/commit/e4ab45aa65d9d73185828d00dcfb216b184afad1
==========

[scheglov, 2016-01-27 17:55:41]

Committed patchset #2 (id:20001) manually as
e4ab45aa65d9d73185828d00dcfb216b184afad1 (presubmit successful).