Add failing test, demonstrating the offset with swedish characters

test/CursorTest.re

@@ -8,6 +8,8 @@ let input = s => ignore(Vim.input(s));
 describe("Cursor", ({describe, _}) => {
   describe("setLocation", ({test, _}) => {
     test("cursor location gets updated", ({expect}) => {
+      let _ = resetBuffer();
+
       Cursor.setLocation(~line=Index.zero, ~column=Index.(zero + 1));
       expect.int((Cursor.getLine() :> int)).toBe(0);
       expect.int((Cursor.getColumn() :> int)).toBe(1);

test/CursorTestSwedish.re

@@ -0,0 +1,47 @@
+open EditorCoreTypes;
+open Vim;
+open TestFramework;
+
+let resetBuffer = () => Helpers.resetBuffer("test/testfile_swedish.txt");
+let input = s => ignore(Vim.input(s));
+
+describe("Cursor with Swedish characters", ({describe, _}) => {
+  describe("normal mode", ({test, _}) => {
+    test("l over a swedish character", ({expect}) => {
+      let _ = resetBuffer();
+
+      let cursorMoves: ref(list(Location.t)) = ref([]);
+      let dispose = Cursor.onMoved(p => cursorMoves := [p, ...cursorMoves^]);
+
+      expect.int((Cursor.getLine() :> int)).toBe(0);
+      expect.int((Cursor.getColumn() :> int)).toBe(0);
+      expect.int(List.length(cursorMoves^)).toBe(0);
+
+      input("l");
+
+      expect.int((Cursor.getLine() :> int)).toBe(0);
+      expect.int((Cursor.getColumn() :> int)).toBe(1);
+
+      dispose();
+    });
+
+    test("l without swedish characters", ({expect}) => {
+      let _ = resetBuffer();
+
+      let cursorMoves: ref(list(Location.t)) = ref([]);
+      let dispose = Cursor.onMoved(p => cursorMoves := [p, ...cursorMoves^]);
+
+      expect.int((Cursor.getLine() :> int)).toBe(0);
+      expect.int((Cursor.getColumn() :> int)).toBe(0);
+      expect.int(List.length(cursorMoves^)).toBe(0);
+
+      input("j");
+      input("l");
+
+      expect.int((Cursor.getLine() :> int)).toBe(1);
+      expect.int((Cursor.getColumn() :> int)).toBe(1);
+
+      dispose();
+    });
+  });
+});

test/testfile_swedish.txt

@@ -0,0 +1,2 @@
+äbcdefgeh
+abcdefgeh