Add test

test/lsp/utils/text_edit.vimspec

@@ -527,6 +527,30 @@ Describe lsp#utils#text_edit
             " Make sure v:completed_item is not changed
             Assert Equals(v:completed_item, l:old_completed_item)
         End
+
+        It replaces entire buffer correctly when end column is 1
+            call s:set_text(['foo', 'b'])
+
+            call lsp#utils#text_edit#apply_text_edits(
+                    \ expand('%'),
+                    \ [{
+                    \   'range': {
+                    \       'start': {
+                    \           'line': 0,
+                    \           'character': 0
+                    \       },
+                    \       'end': {
+                    \           'line': 1,
+                    \           'character': 1
+                    \       }
+                    \   },
+                    \   'newText': "x\ny\nz\n"
+                    \ }])
+
+            let l:buffer_text = s:get_text()
+            Assert Equals(l:buffer_text, ['x', 'y', 'z', 'b', ''])
+        End
+
     End
 End