Add accessors for Maps to the embedding API.

Add accessors for Maps to the embedding API.

(To be used by Dartium.)

R=koda@google.com

Committed: https://code.google.com/p/dart/source/detail?r=36840

[koda, 2014-05-22 23:40:24]

Interface looks good. I'll hook up the fast case for hash maps once they are
internal.

https://codereview.chromium.org/289553002/diff/20001/runtime/include/dart_api.h
File runtime/include/dart_api.h (right):

https://codereview.chromium.org/289553002/diff/20001/runtime/include/dart_api...
runtime/include/dart_api.h:1824: * \return The Object in the Map at the
specified key if no error occurs.
Mention that null is returned if the map does not contain the key.

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:2933: DART_EXPORT Dart_Handle
Dart_MapContainsKey(Dart_Handle map, Dart_Handle key) {
These two functions only differ by the method name resolved. Please consider
sharing their code (possibly also with some List functions above).

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:2945: isolate,
Indentation.

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:2984: instance ^= obj.raw();
To help the reader, please create a new handle (with a descriptive name).

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
File runtime/vm/dart_api_impl_test.cc (right):

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl_test.cc:1354: // Enumerate keys. (Note literal maps
guarentee key order.)
guarentee -> guarantee

[koda, 2014-05-23 00:33:05]

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:2988: args.SetAt(0, instance);
Consider passing in 'false' as an argument to get a fixed size list.

[rmacnak, 2014-05-30 17:23:32]

https://codereview.chromium.org/289553002/diff/20001/runtime/include/dart_api.h
File runtime/include/dart_api.h (right):

https://codereview.chromium.org/289553002/diff/20001/runtime/include/dart_api...
runtime/include/dart_api.h:1824: * \return The Object in the Map at the
specified key if no error occurs.
On 2014/05/22 23:40:24, koda wrote:
> Mention that null is returned if the map does not contain the key.

Done.

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:2933: DART_EXPORT Dart_Handle
Dart_MapContainsKey(Dart_Handle map, Dart_Handle key) {
On 2014/05/22 23:40:24, koda wrote:
> These two functions only differ by the method name resolved. Please consider
> sharing their code (possibly also with some List functions above).

Factored out 0 and 1 argument sends, and used in ListGetAt. Much of list
functions is C/Dart conversion code, so it doesn't share well with the map
functions which only deal with Dart objects.

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:2984: instance ^= obj.raw();
On 2014/05/22 23:40:24, koda wrote:
> To help the reader, please create a new handle (with a descriptive name).

Intermediate result named iterator.

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:2988: args.SetAt(0, instance);
On 2014/05/23 00:33:05, koda wrote:
> Consider passing in 'false' as an argument to get a fixed size list.

Not worth another helper to handle the optional parameter.

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
File runtime/vm/dart_api_impl_test.cc (right):

https://codereview.chromium.org/289553002/diff/20001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl_test.cc:1354: // Enumerate keys. (Note literal maps
guarentee key order.)
On 2014/05/22 23:40:24, koda wrote:
> guarentee -> guarantee

Done.

[koda, 2014-05-30 20:40:23]

LGTM if you cast the argument to prevent leaking internal objects to userland

https://codereview.chromium.org/289553002/diff/40001/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/289553002/diff/40001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:272: const Object& argument) {
Instance seems safer.

[rmacnak, 2014-05-30 21:49:14]

https://codereview.chromium.org/289553002/diff/40001/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/289553002/diff/40001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:272: const Object& argument) {
On 2014/05/30 20:40:23, koda wrote:
> Instance seems safer.

Done.

[rmacnak, 2014-05-30 21:49:33]

Committed patchset #4 manually as r36840 (presubmit successful).