From 142a1c6cf890e5c7626c4c934496fae1eee01715 Mon Sep 17 00:00:00 2001
From: Axetroy <troy450409405@gmail.com>
Date: Tue, 12 Mar 2019 01:14:26 +0800
Subject: [PATCH] add fs/exists (#260)

---
 fs/exists.ts      | 27 +++++++++++++++++++++++++++
 fs/exists_test.ts | 36 ++++++++++++++++++++++++++++++++++++
 fs/testdata/0.ts  |  0
 test.ts           |  1 +
 4 files changed, 64 insertions(+)
 create mode 100644 fs/exists.ts
 create mode 100644 fs/exists_test.ts
 create mode 100644 fs/testdata/0.ts

diff --git a/fs/exists.ts b/fs/exists.ts
new file mode 100644
index 0000000000..aa961037d9
--- /dev/null
+++ b/fs/exists.ts
@@ -0,0 +1,27 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+/**
+ * Test whether or not the given path exists by checking with the file system
+ * @export
+ * @param {string} filePath
+ * @returns {Promise<boolean>}
+ */
+export async function exists(filePath: string): Promise<boolean> {
+  return Deno.stat(filePath)
+    .then(() => true)
+    .catch(() => false);
+}
+
+/**
+ * Test whether or not the given path exists by checking with the file system
+ * @export
+ * @param {string} filePath
+ * @returns {boolean}
+ */
+export function existsSync(filePath: string): boolean {
+  try {
+    Deno.statSync(filePath);
+    return true;
+  } catch {
+    return false;
+  }
+}
diff --git a/fs/exists_test.ts b/fs/exists_test.ts
new file mode 100644
index 0000000000..3d781108e1
--- /dev/null
+++ b/fs/exists_test.ts
@@ -0,0 +1,36 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import { test } from "../testing/mod.ts";
+import { assertEquals } from "../testing/asserts.ts";
+import { exists, existsSync } from "./exists.ts";
+import * as path from "./path/mod.ts";
+
+const testdataDir = path.resolve("fs", "testdata");
+
+test(async function existsFile() {
+  assertEquals(
+    await exists(path.join(testdataDir, "not_exist_file.ts")),
+    false
+  );
+  assertEquals(await existsSync(path.join(testdataDir, "0.ts")), true);
+});
+
+test(function existsFileSync() {
+  assertEquals(existsSync(path.join(testdataDir, "not_exist_file.ts")), false);
+  assertEquals(existsSync(path.join(testdataDir, "0.ts")), true);
+});
+
+test(async function existsDirectory() {
+  assertEquals(
+    await exists(path.join(testdataDir, "not_exist_directory")),
+    false
+  );
+  assertEquals(existsSync(testdataDir), true);
+});
+
+test(function existsDirectorySync() {
+  assertEquals(
+    existsSync(path.join(testdataDir, "not_exist_directory")),
+    false
+  );
+  assertEquals(existsSync(testdataDir), true);
+});
diff --git a/fs/testdata/0.ts b/fs/testdata/0.ts
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/test.ts b/test.ts
index 09ce823dec..63e5ded7b2 100755
--- a/test.ts
+++ b/test.ts
@@ -14,6 +14,7 @@ import "./fs/path/test.ts";
 import "./fs/walk_test.ts";
 import "./fs/globrex_test.ts";
 import "./fs/glob_test.ts";
+import "./fs/exists_test.ts";
 import "./io/test.ts";
 import "./http/server_test.ts";
 import "./http/file_server_test.ts";