From: Ardis Lu <ardisglu@gmail.com>
Date: Tue, 5 Jul 2022 04:01:55 +0000 (-0700)
Subject: Add validation for words and length arguments
X-Git-Tag: v0.1.0~5
X-Git-Url: https://git.ardis.lu/?a=commitdiff_plain;h=f202a4dafe78804e59f71ab8a180a351b9e025e0;p=random-word-generator

Add validation for words and length arguments
---

diff --git a/main.ts b/main.ts
index 53db562..7849966 100644
--- a/main.ts
+++ b/main.ts
@@ -8,10 +8,23 @@ const { words, separator, length } = parse(Deno.args, {
   }
 });
 
+function abort(error: Error) {
+  console.error(error);
+  Deno.exit(1);
+}
+
+// Validate and process words argument
 const dictionary: string[] = [];
-await Deno.readTextFile(words).then(f => dictionary.push(...f.split(/\r?\n/)));
+await Deno.readTextFile(words)
+  .then(f => dictionary.push(...f.split(/\r?\n/)))
+  .catch(abort); // Will throw if an invalid file path is given
 
-const rand = new Uint16Array(parseInt(length));
+// Validate and process length argument
+const len = parseInt(length);
+if (isNaN(len)) {
+  abort(new TypeError(`${length} is not a number.`));
+}
+const rand = new Uint16Array(len);
 crypto.getRandomValues(rand);
 
 const output: string[] = [];