bdb-key: add multi-byte strings/buffers as keys.

lib/db.js

@@ -852,6 +852,7 @@ class Batch {
 
   /**
    * Get bucket.
+   * @param {Buffer} prefix
    * @returns {Batch}
    */
 
@@ -1907,6 +1908,12 @@ function wrap(resolve, reject) {
   };
 }
 
+/**
+ * @param {Buffer|null} prefix
+ * @param {Buffer|null} key
+ * @returns {Buffer?}
+ */
+
 function slice(prefix, key) {
   if (key == null)
     return key;
@@ -1925,6 +1932,12 @@ function slice(prefix, key) {
   return key.slice(prefix.length);
 }
 
+/**
+ * @param {Buffer} prefix
+ * @param {Buffer} key
+ * @returns {Buffer}
+ */
+
 function concat(prefix, key) {
   assert(Buffer.isBuffer(key), 'Key must be a buffer.');
 

lib/key.js

@@ -575,11 +575,10 @@ class Key {
  */
 
 function makeID(id) {
-  if (typeof id === 'string') {
-    assert(id.length === 1);
+  if (typeof id === 'string')
     id =  Buffer.from(id, 'ascii');
-  }
 
+  // Number is not supported for multi-byte ids.
   if (typeof id === 'number') {
     assert((id & 0xff) === id);
     assert(id !== 0xff);

test/key-test.js

@@ -21,6 +21,16 @@ const KEY_IDS = [{
   num: 0x7a, // 'z'
   buf: Buffer.from('z', 'ascii'),
   expected: Buffer.from('z', 'ascii')
+}, {
+  str: 'aa',
+  num: null, // does not support.
+  buf: Buffer.from('aa', 'ascii'),
+  expected: Buffer.from('aa', 'ascii')
+}, {
+  str: 'abcd',
+  num: null, // does not support.
+  buf: Buffer.from('abcd', 'ascii'),
+  expected: Buffer.from('abcd', 'ascii')
 }];
 
 const KEY_OPS = [{
@@ -69,6 +79,11 @@ describe('Key', function() {
     });
 
     it(`should create key for ${KEY_ID.str} (num)`, () => {
+      if (KEY_ID.num == null) {
+        this.skip();
+        return;
+      }
+
       const key = bdb.key(KEY_ID.num);
 
       assert.bufferEqual(key.encode(), KEY_ID.expected);