Add hexWrite test for invalid characters/lengths

test/write-hex.js

@@ -0,0 +1,57 @@
+'use strict'
+
+const Buffer = require('../').Buffer
+const test = require('tape')
+
+test('buffer.write("hex") should stop on invalid characters', function (t) {
+  const buf = Buffer.alloc(4)
+
+  // Test the entire 16-bit space.
+  for (let ch = 0; ch <= 0xffff; ch++) {
+    // 0-9
+    if (ch >= 0x30 && ch <= 0x39) {
+      continue
+    }
+
+    // A-F
+    if (ch >= 0x41 && ch <= 0x46) {
+      continue
+    }
+
+    // a-f
+    if (ch >= 0x61 && ch <= 0x66) {
+      continue
+    }
+
+    const str = 'abcd' + String.fromCharCode(ch) + 'ef0'
+
+    buf.fill(0)
+
+    t.equal(str.length, 8)
+    t.equal(buf.write(str, 'hex'), 2)
+    t.equal(buf.toString('hex'), 'abcd0000')
+    t.equal(Buffer.from(str, 'hex').toString('hex'), 'abcd')
+  }
+
+  t.end()
+})
+
+test('buffer.write("hex") should truncate odd string lengths', function (t) {
+  const buf = Buffer.alloc(32)
+  const charset = '0123456789abcdef'
+
+  let str = ''
+
+  for (let i = 0; i < 63; i++) {
+    str += charset[Math.random() * charset.length | 0]
+  }
+
+  t.equal(buf.write('abcde', 'hex'), 2)
+  t.equal(buf.toString('hex', 0, 3), 'abcd00')
+
+  buf.fill(0)
+
+  t.equal(buf.write(str, 'hex'), 31)
+  t.equal(buf.toString('hex', 0, 32), str.slice(0, -1) + '00')
+  t.end()
+})