commit 66646f312c699bf2f4c70334dcabc21c1470f65b
author Tess Strickland <sstrickl@google.com> Wed Dec 16 11:14:12 2020 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> Wed Dec 16 11:14:12 2020 +0000
tree 37ae376f802314a27b86ec202a709b8a882471cc
parent 868cb26a2d9093983ed022b77ba26be6cb8fb7f7

[vm] Signal bad token positions and lines in KernelLineStartsReader.

First, change LocationForPosition and TokenRangeAtLine to return
whether they successfully located the offset/line. Also change the
wrappers in Script (GetTokenLocation and TokenRangeAtLine) to return
whether or not any information was successfully located.

These methods now only change the out parameters in the case that
appropriate information was found, so any unconditional uses of the out
parameters need the out parameters to be appropriately initialized.

We now allow negative lines to be requested in TokenRangeAtLine (with
the failure behavior described above) so the line returned by
LocationAtPosition can be fed into TokenRangeAtLine without intermediate
checking.

The calculation of the token length, which uses the script source and
not the line starts array, has been moved to a new method,
Script::GetTokenLength.  The new method returns the length (or a
negative value if the token length could not be determined) instead of
using an out parameter.

TEST=Existing tests on trybots, to ensure tests using current
line/number info aren't affected.

Bug: https://github.com/dart-lang/sdk/issues/44436

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-product-x64-try,vm-kernel-linux-product-x64-try,vm-kernel-linux-release-simarm-try,vm-kernel-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm-try
Change-Id: Ibc048a226d11ff9a340a8d249654d07720fdf115
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/175365
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Clement Skau <cskau@google.com>