commit ca2b6dc9be5d081553de75cfe818d0f5012eaf89
author Edwin Kempin <ekempin@google.com> Fri Oct 09 11:29:12 2020 +0200
committer Edwin Kempin <ekempin@google.com> Mon Oct 12 12:19:49 2020 +0200
tree f61edf6f17c7c4b257c3ff6200414f0c3f0bfc09
parent 9f76caea2b03e6c15b332cd9c1ee33bd7c93f2d7

CodeOwnerApprovalCheck: Fix exception when no old path is set for deletion

For deleted files we expect that that the old path is present and that
no new path is set. However for deleted files in merge commits that
resolved a conflict between a file modification in the destination
branch and a deletion in the source branch, the new path was present and
the old path was not set when the comparison was done against the
AutoMerge. This caused an IllegalStateException in
CodeOwnerApprovalCheck saying "old path must be present for
deletion/rename".

The reason for this was that PatchListEntry sets the old path as new
name and the old name is unset (see PatchListEntry constructor), which
is inconsistent with DiffEntry. PatchListEntry is only used when the
comparison is done against the AutoMerge which is why we didn't catch
this bug with the existing tests for file deletions. To fix this we now
get the old path from the new name field in PatchListEntry when we are
constructing a ChangedFile instance from a PatchListEntry for a file
deletion.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I99fd443317f360456bfe3199ac2819b7b19ff0d7