feat: allow first arg in test step to be a function (#17096)

1 files changed, 19 insertions, 0 deletions

diff --git a/cli/tsc/dts/lib.deno.ns.d.ts b/cli/tsc/dts/lib.deno.ns.d.ts
index 7473b1415..b6add6e4b 100644
--- a/cli/tsc/dts/lib.deno.ns.d.ts
+++ b/cli/tsc/dts/lib.deno.ns.d.ts
@@ -668,6 +668,25 @@ declare namespace Deno {
       name: string,
       fn: (t: TestContext) => void | Promise<void>,
     ): Promise<boolean>;
+
+    /** Run a sub step of the parent test or step. Returns a promise
+     * that resolves to a boolean signifying if the step completed successfully.
+     *
+     * The returned promise never rejects unless the arguments are invalid.
+     *
+     * If the test was ignored the promise returns `false`.
+     *
+     * ```ts
+     * Deno.test(async function aParentTest(t) {
+     *   console.log("before the step");
+     *   await t.step(function step1(t) {
+     *     console.log("current step:", t.name);
+     *   });
+     *   console.log("after the step");
+     * });
+     * ```
+     */
+    step(fn: (t: TestContext) => void | Promise<void>): Promise<boolean>;
   }
 
   /** @category Testing */