From 8297f7a18288b5858674f65de17570abd2c139e9 Mon Sep 17 00:00:00 2001
From: epriestley <git@epriestley.com>
Date: Mon, 2 Oct 2017 07:21:38 -0700
Subject: [PATCH] (stable) Fix transaction queries using withComments() for
 transactions with no comments

Summary:
See <https://discourse.phabricator-community.org/t/daemons-tasks-crashing-in-a-loop-during-reindex/506/1>. Some object types (for example, Passphrase Credentials) support indexing but not commenting.

Make `withComments(...)` work properly if the transaction type does not support comments.

Test Plan:
Indexed a credential (no comments) and a revision (comments) with `bin/search index --trace ...`.

Before, credential fataled.

After, credetial succeeds, and skips the transaction query.

Before and after, the revision queries the transaction table.

Reviewers: amckinley

Reviewed By: amckinley

Differential Revision: https://secure.phabricator.com/D18667
---
 ...PhabricatorApplicationTransactionQuery.php | 31 +++++++++++++------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/src/applications/transactions/query/PhabricatorApplicationTransactionQuery.php b/src/applications/transactions/query/PhabricatorApplicationTransactionQuery.php
index abe1498fc0..f15522a087 100644
--- a/src/applications/transactions/query/PhabricatorApplicationTransactionQuery.php
+++ b/src/applications/transactions/query/PhabricatorApplicationTransactionQuery.php
@@ -203,16 +203,29 @@ abstract class PhabricatorApplicationTransactionQuery
       $xaction = $this->getTemplateApplicationTransaction();
       $comment = $xaction->getApplicationTransactionCommentObject();
 
-      if ($this->withComments) {
-        $joins[] = qsprintf(
-          $conn,
-          'JOIN %T c ON x.phid = c.transactionPHID',
-          $comment->getTableName());
+      // Not every transaction type has comments, so we may be able to
+      // implement this constraint trivially.
+
+      if (!$comment) {
+        if ($this->withComments) {
+          throw new PhabricatorEmptyQueryException();
+        } else {
+          // If we're querying for transactions with no comments and the
+          // transaction type does not support comments, we don't need to
+          // do anything.
+        }
       } else {
-        $joins[] = qsprintf(
-          $conn,
-          'LEFT JOIN %T c ON x.phid = c.transactionPHID',
-          $comment->getTableName());
+        if ($this->withComments) {
+          $joins[] = qsprintf(
+            $conn,
+            'JOIN %T c ON x.phid = c.transactionPHID',
+            $comment->getTableName());
+        } else {
+          $joins[] = qsprintf(
+            $conn,
+            'LEFT JOIN %T c ON x.phid = c.transactionPHID',
+            $comment->getTableName());
+        }
       }
     }