feat(std/testing): Add assertExists assertion (#7874)

1 files changed, 29 insertions, 0 deletions

diff --git a/std/testing/asserts_test.ts b/std/testing/asserts_test.ts
index d357a761b..4f153e78c 100644
--- a/std/testing/asserts_test.ts
+++ b/std/testing/asserts_test.ts
@@ -4,6 +4,7 @@ import {
   assert,
   assertArrayIncludes,
   assertEquals,
+  assertExists,
   AssertionError,
   assertMatch,
   assertNotEquals,
@@ -160,6 +161,34 @@ Deno.test("testingNotEquals", function (): void {
   assertEquals(didThrow, true);
 });
 
+Deno.test("testingAssertExists", function (): void {
+  assertExists("Denosaurus");
+  assertExists(false);
+  assertExists(0);
+  assertExists("");
+  assertExists(-0);
+  assertExists(0);
+  assertExists(NaN);
+  let didThrow;
+  try {
+    assertExists(undefined);
+    didThrow = false;
+  } catch (e) {
+    assert(e instanceof AssertionError);
+    didThrow = true;
+  }
+  assertEquals(didThrow, true);
+  didThrow = false;
+  try {
+    assertExists(null);
+    didThrow = false;
+  } catch (e) {
+    assert(e instanceof AssertionError);
+    didThrow = true;
+  }
+  assertEquals(didThrow, true);
+});
+
 Deno.test("testingAssertStringContains", function (): void {
   assertStringIncludes("Denosaurus", "saur");
   assertStringIncludes("Denosaurus", "Deno");