Since today's release, this test is failing:

  1) completion_item_provider
       inserts full text for overrides:
      AssertionError [ERR_ASSERTION]: actual: 8:52-8:52 () vs expected: 8:25-8:51 (throw UnimplementedError())
false !== true
      + expected - actual
      -false
      +true
      at ensureTestSelection (src/test/helpers.ts:993:9)
      at ensureTestContentWithSelection (src/test/helpers.ts:1004:2)
      at Context.<anonymous> (src/test/dart/providers/completion_item_provider.test.ts:136:3)

It appears that after completing this code, the selection is just at the end of the throw UnimplementedError() instead of selecting it: