1 files changed, 37 insertions, 0 deletions
diff --git a/test/bun.js/index-of-line.test.ts b/test/bun.js/index-of-line.test.ts
new file mode 100644
index 000000000..1c6cbaea2
--- /dev/null
+++ b/test/bun.js/index-of-line.test.ts
@@ -0,0 +1,37 @@
+import { expect, test } from "bun:test";
+import { indexOfLine } from "bun";
+
+test("indexOfLine", () => {
+  const source = `
+        const a = 1;
+
+        const b = 2;
+
+        😋const c = 3; // handles unicode
+
+        😋 Get Emoji — All Emojis to ✂️
+
+        const b = 2;
+
+        const c = 3;
+`;
+  var i = 0;
+  var j = 0;
+  const buffer = Buffer.from(source);
+  var nonEmptyLineCount = 0;
+  while (i < buffer.length) {
+    const prev = j;
+    j = source.indexOf("\n", j);
+    i = indexOfLine(buffer, i);
+
+    const delta = Buffer.byteLength(source.slice(0, j), "utf8") - j;
+    console.log(source.slice(prev + 1, j));
+    if (i === -1) {
+      expect(j).toBe(-1);
+      expect(nonEmptyLineCount).toBe(6);
+      break;
+    }
+    expect(i++ - delta).toBe(j++);
+    nonEmptyLineCount++;
+  }
+});