1 files changed, 29 insertions, 0 deletions
diff --git a/src/util/time.ts b/src/util/time.ts
new file mode 100644
index 0000000..73990ad
--- /dev/null
+++ b/src/util/time.ts
@@ -0,0 +1,29 @@
+export const sleep = (ms: number, signal?: AbortSignal): Promise<void> =>
+  new Promise((resolve, reject) => {
+    if (signal?.aborted) {
+      reject(new Error("aborted"));
+      return;
+    }
+    const timer = setTimeout(() => {
+      signal?.removeEventListener("abort", onAbort);
+      resolve();
+    }, ms);
+    const onAbort = (): void => {
+      clearTimeout(timer);
+      reject(new Error("aborted"));
+    };
+    signal?.addEventListener("abort", onAbort, { once: true });
+  });
+
+export type Deadline = {
+  readonly remainingMs: () => number;
+  readonly expired: () => boolean;
+};
+
+export const deadline = (totalMs: number): Deadline => {
+  const end = Date.now() + totalMs;
+  return {
+    remainingMs: () => Math.max(0, end - Date.now()),
+    expired: () => Date.now() >= end,
+  };
+};