commit e60cbdfd9e846a566fe7816c78ad94f603c57b08
author Jens Johansen <jensj@google.com> Tue Aug 20 12:27:52 2019 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> Tue Aug 20 12:27:52 2019 +0000
tree 2528233303917b7921642ec4fa422197b12147bc
parent de45a837551d638183db8a9e70698b58ca6d925d

[CFE] Add test for running old dills

This CL:
* adds a test that runs the VM with old dills (compilations of dart2js
  with old checkouts) with the --compile_all argument (1).
* adds a number of old dills (for binary version 25, 27, 28, 29)
  (by mistake binary version 26 sort of didn't really happen)
* adds a PRESUBMIT check in kernel that verifies that we have an
  "old dill" for the current binary version, so one don't bump the
  version without creating a new dill.

(1): It uses --compile_all to force the VM to "read and understand"
     everything in the dill file. The hope being that we try out
     all/most language constructs and thus verifies that they can be
     read by the VM.

Old "old dill" files should be removed once the VM stops supporting that
version. That is a manual process, but a test should complain that the VM
cannot read the old "old dill"(s) once/if that happens.

This should (help) detect errors such as the one recently where a merge
error caused a single "if >= 28" (that should have been "if >= 29" and
thus stopped the VM from reading dills from version 28) to slip through
and require a lot of debugging a few days later.

Change-Id: Id79e16c7ad896c0ccc4e181465b05b67822ac31a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/113698
Commit-Queue: Jens Johansen <jensj@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>