1 files changed, 31 insertions, 0 deletions
diff --git a/cli/tests/unit/symlink_test.ts b/cli/tests/unit/symlink_test.ts
index b5700b4f3..f0db2d615 100644
--- a/cli/tests/unit/symlink_test.ts
+++ b/cli/tests/unit/symlink_test.ts
@@ -1,6 +1,7 @@
 // Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
 import {
   assert,
+  assertRejects,
   assertThrows,
   pathToAbsoluteFileUrl,
   unitTest,
@@ -47,6 +48,21 @@ unitTest(function symlinkSyncPerm() {
 
 unitTest(
   { permissions: { read: true, write: true } },
+  function symlinkSyncAlreadyExist() {
+    const existingFile = Deno.makeTempFileSync();
+    const existingFile2 = Deno.makeTempFileSync();
+    assertThrows(
+      () => {
+        Deno.symlinkSync(existingFile, existingFile2);
+      },
+      Deno.errors.AlreadyExists,
+      `symlink '${existingFile}' -> '${existingFile2}'`,
+    );
+  },
+);
+
+unitTest(
+  { permissions: { read: true, write: true } },
   async function symlinkSuccess() {
     const testDir = Deno.makeTempDirSync();
     const oldname = testDir + "/oldname";
@@ -77,3 +93,18 @@ unitTest(
     assert(newNameInfoStat.isDirectory, "NOT DIRECTORY");
   },
 );
+
+unitTest(
+  { permissions: { read: true, write: true } },
+  async function symlinkAlreadyExist() {
+    const existingFile = Deno.makeTempFileSync();
+    const existingFile2 = Deno.makeTempFileSync();
+    await assertRejects(
+      async () => {
+        await Deno.symlink(existingFile, existingFile2);
+      },
+      Deno.errors.AlreadyExists,
+      `symlink '${existingFile}' -> '${existingFile2}'`,
+    );
+  },
+);