[PATCH 16/18] merge-ort: process_renames() now needs more defensiveness

From: Elijah Newren via GitGitGadget <gitgitgadget@gmail.com>
Date: Jan 7, 2021, 20:01 UTC
Message-ID: <11e45af831d14296c6a78441e423aba315c8f76b.1610049687.git.gitgitgadget@gmail.com>
In-Reply-To: <pull.835.git.1610049687.gitgitgadget@gmail.com>

From: Elijah Newren <newren@gmail.com>

Since directory rename detection adds new paths to opt->priv->paths and removes old ones, process_renames() needs to now check whether pair->one->path actually exists in opt->priv->paths instead of just assuming it does.

Signed-off-by: Elijah Newren <newren@gmail.com>
---
 merge-ort.c | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/merge-ort.c b/merge-ort.c
index ea6a08e23e2..9e4ebd9c4d6 100644
--- a/merge-ort.c
+++ b/merge-ort.c
@@ -1411,12 +1411,28 @@ static int process_renames(struct merge_options *opt,
 		const char *rename_branch = NULL, *delete_branch = NULL;
 
 		old_ent = strmap_get_entry(&opt->priv->paths, pair->one->path);
-		oldpath = old_ent->key;
-		oldinfo = old_ent->value;
-
 		new_ent = strmap_get_entry(&opt->priv->paths, pair->two->path);
-		newpath = new_ent->key;
-		newinfo = new_ent->value;
+		if (old_ent) {
+			oldpath = old_ent->key;
+			oldinfo = old_ent->value;
+		}
+		newpath = pair->two->path;
+		if (new_ent) {
+			newpath = new_ent->key;
+			newinfo = new_ent->value;
+		}
+
+		/*
+		 * If pair->one->path isn't in opt->priv->paths, that means
+		 * that either directory rename detection removed that
+		 * path, or a parent directory of oldpath was resolved and
+		 * we don't even need the rename; in either case, we can
+		 * skip it.  If oldinfo->merged.clean, then the other side
+		 * of history had no changes to oldpath and we don't need
+		 * the rename and can skip it.
+		 */
+		if (!oldinfo || oldinfo->merged.clean)
+			continue;
 
 		/*
 		 * diff_filepairs have copies of pathnames, thus we have to

-- 
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