Fix blame opening from (un)staged changes diff view

When showing the diff of staged or unstaged changes commit opened from
the main view, the commit ID is the magic all-zero SHA (00000...)  which
caused git-blame to choke. Detect this so that blame can be opened even
from these diff views.

1 files changed, 4 insertions, 1 deletions

diff --git a/src/diff.c b/src/diff.c
index 1e7460b0..b13cbd79 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -348,7 +348,10 @@ diff_trace_origin(struct view *view, struct line *line)
 	else
 		string_format(ref, "%s^", view->vid);
 
-	if (!diff_blame_line(ref, file, lineno, &header, &commit)) {
+	if (string_rev_is_null(ref)) {
+		header.id[0] = 0;
+		header.orig_lineno = lineno;
+	} else if (!diff_blame_line(ref, file, lineno, &header, &commit)) {
 		report("Failed to read blame data");
 		return REQ_NONE;
 	}