Implementation of the 'search.getTypeHierarchy' API.

Implementation of the 'search.getTypeHierarchy' API.

R=paulberry@google.com
BUG=

Committed: https://code.google.com/p/dart/source/detail?r=38626

[Paul Berry, 2014-07-25 22:02:27]

lgtm

https://codereview.chromium.org/422573003/diff/1/pkg/analysis_server/lib/src/...
File pkg/analysis_server/lib/src/search/type_hierarchy.dart (right):

https://codereview.chromium.org/422573003/diff/1/pkg/analysis_server/lib/src/...
pkg/analysis_server/lib/src/search/type_hierarchy.dart:53: return null;
I see how this prevents recursion, but it seems like it also screws up diamond
relationships in the class hierarchy.  For example:

class A {}
class B extends A {}
class C implements A {}
class D extends B implements C {}

It looks like the relationship "C implements A" will be recorded as "C
implements null", because by the time we visit C, A has already been processed. 
(This is particularly problematic because according to the API spec, the
"interfaces" list isn't allowed to contain null).

One way to fix this would be to add a "truncated" flag to TypeHierarchyItem. 
Then, instead of returning null, we would do:

return new TypeHierarchyItem(classElement, memberElement, displayName, [], [],
truncated: true);

A nice side effect of this is that not only would it improve legitimate cases
like the example above, it would also improve the display of illegal cases like:

class A extends B {}
class B extends A {}

because the client could show a type hierarchy of:

A (truncated)
..B
....A

I'd be ok if you want to commit this CL as is for now, though; we can discuss
this issue next week when Brian is back in the office.

https://codereview.chromium.org/422573003/diff/1/pkg/analysis_server/lib/src/...
pkg/analysis_server/lib/src/search/type_hierarchy.dart:95: ExecutableElement
findMemberElement(ClassElement classElemnet) {
s/classElemnet/classElement/

[scheglov, 2014-07-28 15:52:34]

Committed patchset #1 manually as r38626 (presubmit successful).