CodeOwnerApprovalCheck: Add debug logs for pure reverts

We should be able to see from a trace whether pure reverts are
configured to be exempted from requiring code owner approvals and
whether a change was found to be a pure revert.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: Ic37f1c29413ed5ae801ce53344aceab6ba7d7bd0
diff --git a/java/com/google/gerrit/plugins/codeowners/backend/CodeOwnerApprovalCheck.java b/java/com/google/gerrit/plugins/codeowners/backend/CodeOwnerApprovalCheck.java
index 4c41510..b563d84 100644
--- a/java/com/google/gerrit/plugins/codeowners/backend/CodeOwnerApprovalCheck.java
+++ b/java/com/google/gerrit/plugins/codeowners/backend/CodeOwnerApprovalCheck.java
@@ -238,7 +238,11 @@
       CodeOwnersPluginConfigSnapshot codeOwnersConfig =
           codeOwnersPluginConfiguration.getProjectConfig(changeNotes.getProjectName());
 
-      if (codeOwnersConfig.arePureRevertsExempted() && isPureRevert(changeNotes)) {
+      boolean arePureRevertsExempted = codeOwnersConfig.arePureRevertsExempted();
+      logger.atFine().log("arePureRevertsExempted = %s", arePureRevertsExempted);
+      if (arePureRevertsExempted && isPureRevert(changeNotes)) {
+        logger.atFine().log(
+            "change is a pure revert and is exempted from requiring code owner approvals");
         return getAllPathsAsApproved(changeNotes, changeNotes.getCurrentPatchSet());
       }