From cf21773e6fe81ea27c958d127153205edc4ea75c Mon Sep 17 00:00:00 2001
From: Patrick Cleaveliln <patrick@spacegirl.nl>
Date: Sat, 12 Jul 2025 03:49:06 +0000
Subject: [PATCH] fix cursor bug + fix crash

---
 src/core/file_buffer.odin | 18 ++++++++++--------
 src/panels/panels.odin    | 12 +++++++-----
 src/tests/tests.odin      | 22 ++++++++++++++++++++++
 3 files changed, 39 insertions(+), 13 deletions(-)

diff --git a/src/core/file_buffer.odin b/src/core/file_buffer.odin
index 1a8ca90..0dff5ce 100644
--- a/src/core/file_buffer.odin
+++ b/src/core/file_buffer.odin
@@ -88,16 +88,18 @@ file_buffer_end :: proc(buffer: ^FileBuffer) -> Cursor {
 iterate_file_buffer :: proc(it: ^FileBufferIter) -> (character: u8, idx: PieceTableIndex, cond: bool) {
     character, idx, cond = iterate_piece_table_iter(&it.piter)
 
-    if character == '\n' {
-        it.cursor.col = 0
-        it.cursor.line += 1
-    } else {
-        it.cursor.col += 1
-    }
-
     it.cursor.index = it.piter.index
     it.hit_end = it.piter.hit_end
 
+    if cond && !it.hit_end {
+        if character == '\n' {
+            it.cursor.col = 0
+            it.cursor.line += 1
+        } else {
+            it.cursor.col += 1
+        }
+    }
+
     return
 }
 
@@ -108,7 +110,7 @@ iterate_file_buffer_reverse :: proc(it: ^FileBufferIter) -> (character: u8, idx:
     it.cursor.index = it.piter.index
     it.hit_end = it.piter.hit_end
 
-    if cond {
+    if cond && !it.hit_end {
         if it.cursor.col > 0 {
             it.cursor.col -= 1
         } else if it.cursor.line > 0 {
diff --git a/src/panels/panels.odin b/src/panels/panels.odin
index 6f8cfd7..c056aab 100644
--- a/src/panels/panels.odin
+++ b/src/panels/panels.odin
@@ -301,11 +301,13 @@ make_grep_panel :: proc(state: ^core.State) -> core.Panel {
         free_grep_results(rs_results)
 
         panel_state.selected_result = 0
-        core.update_glyph_buffer_from_bytes(
-            &panel_state.glyphs,
-            transmute([]u8)panel_state.query_results[panel_state.selected_result].file_context,
-            panel_state.query_results[panel_state.selected_result].line,
-        )
+        if len(panel_state.query_results) > 0 {
+            core.update_glyph_buffer_from_bytes(
+                &panel_state.glyphs,
+                transmute([]u8)panel_state.query_results[panel_state.selected_result].file_context,
+                panel_state.query_results[panel_state.selected_result].line,
+            )
+        }
     }
 
     core.register_key_action(&input_map.mode[.Normal], .ENTER, proc(state: ^core.State) {
diff --git a/src/tests/tests.odin b/src/tests/tests.odin
index 6c0a03a..7d5ac0e 100644
--- a/src/tests/tests.odin
+++ b/src/tests/tests.odin
@@ -536,6 +536,28 @@ move_to_beginning_of_line_from_start :: proc(t: ^testing.T) {
     expect_cursor_index(t, buffer.cursor, 0, 0)
 }
 
+@(test)
+append_end_of_line :: proc(t: ^testing.T) {
+    e := new_test_editor()
+    setup_empty_buffer(&e)
+
+    buffer := &e.buffers[0]
+
+    run_text_insertion(&e, "hello")
+
+    run_input_multiple(&e, press_key(.A), 1)
+    run_input_multiple(&e, press_key(.ESCAPE), 1)
+
+    expect_line_col(t, buffer.cursor, 0, 5)
+    expect_cursor_index(t, buffer.cursor, 1, 0)
+
+    run_input_multiple(&e, press_key(.A), 1)
+    run_input_multiple(&e, press_key(.ESCAPE), 1)
+
+    expect_line_col(t, buffer.cursor, 0, 5)
+    expect_cursor_index(t, buffer.cursor, 1, 0)
+}
+
 @(test)
 insert_line_under_current :: proc(t: ^testing.T) {
     e := new_test_editor()