Spreadsheet: Prevent OOB access to text editor buffer

For some reason LibGUI sends two events for each edit, and one of them
contains an OOB cursor if a character was deleted.
This works around that for now.

1 files changed, 1 insertions, 0 deletions

diff --git a/Userland/Applications/Spreadsheet/SpreadsheetWidget.cpp b/Userland/Applications/Spreadsheet/SpreadsheetWidget.cpp
index 330a3d14ed..dbc58e0519 100644
--- a/Userland/Applications/Spreadsheet/SpreadsheetWidget.cpp
+++ b/Userland/Applications/Spreadsheet/SpreadsheetWidget.cpp
@@ -383,6 +383,7 @@ void SpreadsheetWidget::try_generate_tip_for_input_expression(StringView source,
         m_inline_documentation_window->hide();
         return;
     }
+    cursor_offset = min(cursor_offset, source.length());
     auto maybe_function_and_argument = get_function_and_argument_index(source.substring_view(0, cursor_offset));
     if (!maybe_function_and_argument.has_value()) {
         m_inline_documentation_window->hide();