From c2a1180df6cb44d73abf0412e2c10efc4f0438f0 Mon Sep 17 00:00:00 2001
From: Jesse Luehrs <doy@tozt.net>
Date: Fri, 3 Dec 2021 02:46:27 -0500
Subject: fix keeping cursor past end of line with diffs

---
 src/row.rs                           |  6 ++++--
 tests/data/fixtures/el.in            |  2 ++
 tests/data/fixtures/el/25.json       | 15 +++++++++++++++
 tests/data/fixtures/el/25.typescript |  1 +
 tests/data/fixtures/el/26.json       | 12 ++++++++++++
 tests/data/fixtures/el/26.typescript |  1 +
 6 files changed, 35 insertions(+), 2 deletions(-)
 create mode 100644 tests/data/fixtures/el/25.json
 create mode 100644 tests/data/fixtures/el/25.typescript
 create mode 100644 tests/data/fixtures/el/26.json
 create mode 100644 tests/data/fixtures/el/26.typescript

diff --git a/src/row.rs b/src/row.rs
index b15266e..e666cb7 100644
--- a/src/row.rs
+++ b/src/row.rs
@@ -446,8 +446,10 @@ impl Row {
                 crate::term::EraseChar::new(1).write_buf(contents);
             }
             let end_cell = self.get(end_pos.col).unwrap();
-            contents.extend(end_cell.contents().as_bytes());
-            prev_pos.col += if end_cell.is_wide() { 2 } else { 1 };
+            if end_cell.has_contents() {
+                contents.extend(end_cell.contents().as_bytes());
+                prev_pos.col += if end_cell.is_wide() { 2 } else { 1 };
+            }
         }
 
         (prev_pos, prev_attrs)
diff --git a/tests/data/fixtures/el.in b/tests/data/fixtures/el.in
index f5f679c..1c132bd 100644
--- a/tests/data/fixtures/el.in
+++ b/tests/data/fixtures/el.in
@@ -22,3 +22,5 @@ foo\x1b[5;5Hbarbar\x1b[10;10Hbazbaz\x1b[20;20Hquux
 \x1bc\x1b[1;80H\x1b[41ma\x1b[1K
 \x1bc\x1b[1;80H\x1b[41maa\x1b[1K
 \x1bc\x1b[41m\x1b[2J\x1b[1;80Haa\x1b[1K
+\x1bc\x1b[1;80Hab\x1b[1;80Hc
+\x1b[2K
diff --git a/tests/data/fixtures/el/25.json b/tests/data/fixtures/el/25.json
new file mode 100644
index 0000000..504426c
--- /dev/null
+++ b/tests/data/fixtures/el/25.json
@@ -0,0 +1,15 @@
+{
+  "contents": "                                                                               cb",
+  "cells": {
+    "0,79": {
+      "contents": "c"
+    },
+    "1,0": {
+      "contents": "b"
+    }
+  },
+  "cursor_position": [
+    0,
+    80
+  ]
+}
\ No newline at end of file
diff --git a/tests/data/fixtures/el/25.typescript b/tests/data/fixtures/el/25.typescript
new file mode 100644
index 0000000..40224c4
--- /dev/null
+++ b/tests/data/fixtures/el/25.typescript
@@ -0,0 +1 @@
+cabc
\ No newline at end of file
diff --git a/tests/data/fixtures/el/26.json b/tests/data/fixtures/el/26.json
new file mode 100644
index 0000000..661055f
--- /dev/null
+++ b/tests/data/fixtures/el/26.json
@@ -0,0 +1,12 @@
+{
+  "contents": "\nb",
+  "cells": {
+    "1,0": {
+      "contents": "b"
+    }
+  },
+  "cursor_position": [
+    0,
+    80
+  ]
+}
\ No newline at end of file
diff --git a/tests/data/fixtures/el/26.typescript b/tests/data/fixtures/el/26.typescript
new file mode 100644
index 0000000..d2e06ee
--- /dev/null
+++ b/tests/data/fixtures/el/26.typescript
@@ -0,0 +1 @@
+
\ No newline at end of file
-- 
cgit v1.2.3-54-g00ecf