From 35061af11bf13f0b28dfbeb69c9c1274fad9d544 Mon Sep 17 00:00:00 2001
From: kalsprite <jon@lipstate.com>
Date: Sun, 16 Aug 2026 17:31:59 -0700
Subject: [PATCH] fix eol diagnostic

---
 src/error.cpp  | 6 ++++--
 src/parser.cpp | 6 ++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/error.cpp b/src/error.cpp
index 53bc01654..ee2d79c27 100644
--- a/src/error.cpp
+++ b/src/error.cpp
@@ -432,8 +432,10 @@ gb_internal isize show_error_on_line(TokenPos const &pos, TokenPos end) {
 		window_close_bytes = line_length_bytes;
 	}
 
-	for (i32 i = error_start_index_graphemes; i > 0; i -= 1) {
-		if (graphemes[i].byte_index == window_open_bytes) {
+	// counts the graphemes before the error. It must not read the one at it: an error at the
+	// end of a line indexes one past the last grapheme
+	for (i32 i = error_start_index_graphemes-1; i >= 0; i -= 1) {
+		if (graphemes[i].byte_index < window_open_bytes) {
 			break;
 		}
 		squiggle_padding += graphemes[i].width;
diff --git a/src/parser.cpp b/src/parser.cpp
index d981491dd..f8d5cb1b8 100644
--- a/src/parser.cpp
+++ b/src/parser.cpp
@@ -113,6 +113,12 @@ gb_internal gbString get_file_line_as_string(TokenPos const &pos, i32 *offset_)
 	if (len < offset) {
 		return nullptr;
 	}
+
+	// a column past the first cannot belong to a line the offset has already left
+	if (offset > 0 && pos.column > 1 && start[offset-1] == '\n') {
+		offset -= 1;
+	}
+
 	u8 *pos_offset = start+offset;
 
 	u8 *line_start = pos_offset;