1 files changed, 64 insertions, 0 deletions
diff --git a/std/fs/ensure_file.ts b/std/fs/ensure_file.ts
new file mode 100644
index 000000000..d749b95e4
--- /dev/null
+++ b/std/fs/ensure_file.ts
@@ -0,0 +1,64 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import * as path from "./path/mod.ts";
+import { ensureDir, ensureDirSync } from "./ensure_dir.ts";
+import { getFileInfoType } from "./utils.ts";
+
+/**
+ * Ensures that the file exists.
+ * If the file that is requested to be created is in directories that do not
+ * exist.
+ * these directories are created. If the file already exists,
+ * it is NOTMODIFIED.
+ */
+export async function ensureFile(filePath: string): Promise<void> {
+  let pathExists = false;
+  try {
+    // if file exists
+    const stat = await Deno.lstat(filePath);
+    pathExists = true;
+    if (!stat.isFile()) {
+      throw new Error(
+        `Ensure path exists, expected 'file', got '${getFileInfoType(stat)}'`
+      );
+    }
+  } catch (err) {
+    if (pathExists) {
+      throw err;
+    }
+    // if file not exists
+    // ensure dir exists
+    await ensureDir(path.dirname(filePath));
+    // create file
+    await Deno.writeFile(filePath, new Uint8Array());
+  }
+}
+
+/**
+ * Ensures that the file exists.
+ * If the file that is requested to be created is in directories that do not
+ * exist,
+ * these directories are created. If the file already exists,
+ * it is NOT MODIFIED.
+ */
+export function ensureFileSync(filePath: string): void {
+  let pathExists = false;
+  try {
+    // if file exists
+    const stat = Deno.statSync(filePath);
+    pathExists = true;
+    if (!stat.isFile()) {
+      throw new Error(
+        `Ensure path exists, expected 'file', got '${getFileInfoType(stat)}'`
+      );
+    }
+  } catch (err) {
+    if (pathExists) {
+      throw err;
+    }
+    // if file not exists
+    // ensure dir exists
+    ensureDirSync(path.dirname(filePath));
+    // create file
+    Deno.writeFileSync(filePath, new Uint8Array());
+  }
+}