This adds checks for three cases:
- error codes for diagnostics that are not being produced,
- error codes that can't be ignored (with a severity of error), and
- error codes that are already being ignored.
I originally also checked for names that are not defined as error codes
(which turned up at least one valid issue in the Flutter repo), but we
don't have a list of all valid names against which to compare because
plugins can add new diagnostics.
It should be noted that, as written, these diagnostics can't be ignored,
despite being hints. The reason is as follows: in order to detect
diagnostics that are not being produced, these checks need to have a
list of the diagnostics that _are_ produced. If an ignore comment
attempted to ignore one of these hints, this validation would occur
before the hint had been generated, so that comment would in turn appear
to be unnecessary.
If we need them to be ignorable, then we can special case them so that
they are never reported as being unnecessary.
And after running this over the Flutter repo I commented out two of the
three codes because there are violations. Many of the violations are
valid and need to be cleaned up. Some are the result of "ignore" being
used for other purposes. The Flutter team has said that we can replace
their use of "ignore" in order to enable these hints, but I don't have
time to do that right now and I'd like to get this landed before it bit
rots again.
Change-Id: I1704105621bef5a5c49202267c99aa1d950a26a9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/156402
Commit-Queue: Brian Wilkerson <brianwilkerson@google.com>
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Brian Wilkerson
35ce26e0db