feat(node/fs): add fstat and fstatSync (#847)

node/_fs/_fs_fstat.ts

@@ -0,0 +1,59 @@
+import {
+  BigIntStats,
+  CFISBIS,
+  statCallback,
+  statCallbackBigInt,
+  statOptions,
+  Stats,
+} from "./_fs_stat.ts";
+
+export function fstat(fd: number, callback: statCallback): void;
+export function fstat(
+  fd: number,
+  options: { bigint: false },
+  callback: statCallback,
+): void;
+export function fstat(
+  fd: number,
+  options: { bigint: true },
+  callback: statCallbackBigInt,
+): void;
+export function fstat(
+  fd: number,
+  optionsOrCallback: statCallback | statCallbackBigInt | statOptions,
+  maybeCallback?: statCallback | statCallbackBigInt,
+) {
+  const callback =
+    (typeof optionsOrCallback === "function"
+      ? optionsOrCallback
+      : maybeCallback) as (
+        ...args: [Error] | [null, BigIntStats | Stats]
+      ) => void;
+  const options = typeof optionsOrCallback === "object"
+    ? optionsOrCallback
+    : { bigint: false };
+
+  if (!callback) throw new Error("No callback function supplied");
+
+  Deno.fstat(fd).then(
+    (stat) => callback(null, CFISBIS(stat, options.bigint)),
+    (err) => callback(err),
+  );
+}
+
+export function fstatSync(fd: number): Stats;
+export function fstatSync(
+  fd: number,
+  options: { bigint: false },
+): Stats;
+export function fstatSync(
+  fd: number,
+  options: { bigint: true },
+): BigIntStats;
+export function fstatSync(
+  fd: number,
+  options?: statOptions,
+): Stats | BigIntStats {
+  const origin = Deno.fstatSync(fd);
+  return CFISBIS(origin, options?.bigint || false);
+}

node/_fs/_fs_fstat_test.ts

@@ -0,0 +1,82 @@
+import { fstat, fstatSync } from "./_fs_fstat.ts";
+import { fail } from "../../testing/asserts.ts";
+import { assertStats, assertStatsBigInt } from "./_fs_stat_test.ts";
+import type { BigIntStats, Stats } from "./_fs_stat.ts";
+
+Deno.test({
+  name: "ASYNC: get a file Stats",
+  async fn() {
+    const file = await Deno.makeTempFile();
+    const { rid } = await Deno.open(file);
+
+    await new Promise<Stats>((resolve, reject) => {
+      fstat(rid, (err: Error | null, stat: Stats) => {
+        if (err) reject(err);
+        resolve(stat);
+      });
+    })
+      .then(
+        (stat) => {
+          assertStats(stat, Deno.fstatSync(rid));
+        },
+        () => fail(),
+      )
+      .finally(() => {
+        Deno.removeSync(file);
+        Deno.close(rid);
+      });
+  },
+});
+
+Deno.test({
+  name: "ASYNC: get a file BigInt Stats",
+  async fn() {
+    const file = await Deno.makeTempFile();
+    const { rid } = await Deno.open(file);
+
+    await new Promise<BigIntStats>((resolve, reject) => {
+      fstat(rid, { bigint: true }, (err: Error | null, stat: BigIntStats) => {
+        if (err) reject(err);
+        resolve(stat);
+      });
+    })
+      .then(
+        (stat) => assertStatsBigInt(stat, Deno.fstatSync(rid)),
+        () => fail(),
+      )
+      .finally(() => {
+        Deno.removeSync(file);
+        Deno.close(rid);
+      });
+  },
+});
+
+Deno.test({
+  name: "SYNC: get a file Stats",
+  fn() {
+    const file = Deno.makeTempFileSync();
+    const { rid } = Deno.openSync(file);
+
+    try {
+      assertStats(fstatSync(rid), Deno.fstatSync(rid));
+    } finally {
+      Deno.removeSync(file);
+      Deno.close(rid);
+    }
+  },
+});
+
+Deno.test({
+  name: "SYNC: get a file BigInt Stats",
+  fn() {
+    const file = Deno.makeTempFileSync();
+    const { rid } = Deno.openSync(file);
+
+    try {
+      assertStatsBigInt(fstatSync(rid, { bigint: true }), Deno.fstatSync(rid));
+    } finally {
+      Deno.removeSync(file);
+      Deno.close(rid);
+    }
+  },
+});