Add `console.assert` (#102)

2 files changed, 19 insertions, 0 deletions

diff --git a/globals.ts b/globals.ts
index ed60bc46a..b8944b4be 100644
--- a/globals.ts
+++ b/globals.ts
@@ -32,6 +32,13 @@ _global["console"] = {
   // tslint:disable-next-line:no-any
   error(...args: any[]): void {
     print("ERROR: " + stringifyArgs(args));
+  },
+
+  // tslint:disable-next-line:no-any
+  assert(condition: boolean, ...args: any[]): void {
+    if (!condition) {
+      throw new Error("Assertion failed: " + stringifyArgs(args));
+    }
   }
 };
 
diff --git a/tests.ts b/tests.ts
index d4b188fda..406ac76e8 100644
--- a/tests.ts
+++ b/tests.ts
@@ -19,6 +19,18 @@ test(async function tests_fetch() {
   assertEqual(json.name, "deno");
 });
 
+test(function tests_console_assert() {
+  console.assert(true);
+
+  let hasThrown = false;
+  try {
+    console.assert(false);
+  } catch {
+    hasThrown = true;
+  }
+  assertEqual(hasThrown, true);
+});
+
 test(async function tests_readFileSync() {
   const data = readFileSync("package.json");
   if (!data.byteLength) {