Add cursor moving (#19)

frontend/obsidian-plugin/src/utils/position-to-line-and-column.test.ts

@@ -0,0 +1,69 @@
+import { positionToLineAndColumn } from "./position-to-line-and-column";
+
+describe("positionToLineAndColumn", () => {
+	test("converts position to line and column in a single line text", () => {
+		const text = "Hello, world!";
+		expect(positionToLineAndColumn(text, 0)).toEqual({
+			line: 0,
+			column: 1
+		});
+		expect(positionToLineAndColumn(text, 7)).toEqual({
+			line: 0,
+			column: 8
+		});
+		expect(positionToLineAndColumn(text, 12)).toEqual({
+			line: 0,
+			column: 13
+		});
+	});
+
+	test("converts position to line and column in multi-line text", () => {
+		const text = "First line\nSecond line\nThird line";
+		expect(positionToLineAndColumn(text, 0)).toEqual({
+			line: 0,
+			column: 1
+		});
+		expect(positionToLineAndColumn(text, 10)).toEqual({
+			line: 0,
+			column: 11
+		});
+		expect(positionToLineAndColumn(text, 15)).toEqual({
+			line: 1,
+			column: 5
+		});
+		expect(positionToLineAndColumn(text, 26)).toEqual({
+			line: 2,
+			column: 4
+		});
+	});
+
+	test("handles positions at line breaks", () => {
+		const text = "Line\nBreak";
+		expect(positionToLineAndColumn(text, 4)).toEqual({
+			line: 0,
+			column: 5
+		});
+		expect(positionToLineAndColumn(text, 5)).toEqual({
+			line: 1,
+			column: 1
+		});
+	});
+
+	test("handles empty input", () => {
+		expect(positionToLineAndColumn("", 0)).toEqual({ line: 0, column: 1 });
+	});
+
+	test("handles positions at the end of text", () => {
+		const text = "End";
+		expect(positionToLineAndColumn(text, 3)).toEqual({
+			line: 0,
+			column: 4
+		});
+	});
+
+	test("throws error for position out of range", () => {
+		const text = "Short text";
+		expect(() => positionToLineAndColumn(text, 15)).toThrow();
+		expect(() => positionToLineAndColumn(text, -1)).toThrow();
+	});
+});