Fix for raw inflate with dictionary (#156)

Fixes https://github.com/nodeca/pako/issues/155
`inflateSetDictionary()` is called at different conditions during normal and raw modes, according to http://zlib.net/manual.html#Advanced 
Also providing basic tests for raw inflate with directory, and fix for broken test Inflate with dictionary/spdy dictionary

lib/inflate.js

@@ -144,6 +144,22 @@ function Inflate(options) {
   this.header = new GZheader();
 
   zlib_inflate.inflateGetHeader(this.strm, this.header);
+
+  // Setup dictionary
+  if (opt.dictionary) {
+    // Convert data if needed
+    if (typeof opt.dictionary === 'string') {
+      opt.dictionary = strings.string2buf(opt.dictionary);
+    } else if (toString.call(opt.dictionary) === '[object ArrayBuffer]') {
+      opt.dictionary = new Uint8Array(opt.dictionary);
+    }
+    if (opt.raw) { //In raw mode we need to set the dictionary early
+      status = zlib_inflate.inflateSetDictionary(this.strm, opt.dictionary);
+      if (status !== c.Z_OK) {
+        throw new Error(msg[status]);
+      }
+    }
+  }
 }
 
 /**
@@ -180,7 +196,6 @@ Inflate.prototype.push = function (data, mode) {
   var dictionary = this.options.dictionary;
   var status, _mode;
   var next_out_utf8, tail, utf8str;
-  var dict;
 
   // Flag to properly process Z_BUF_ERROR on testing inflate call
   // when we check that all output data was flushed.
@@ -212,17 +227,7 @@ Inflate.prototype.push = function (data, mode) {
     status = zlib_inflate.inflate(strm, c.Z_NO_FLUSH);    /* no bad return value */
 
     if (status === c.Z_NEED_DICT && dictionary) {
-      // Convert data if needed
-      if (typeof dictionary === 'string') {
-        dict = strings.string2buf(dictionary);
-      } else if (toString.call(dictionary) === '[object ArrayBuffer]') {
-        dict = new Uint8Array(dictionary);
-      } else {
-        dict = dictionary;
-      }
-
-      status = zlib_inflate.inflateSetDictionary(this.strm, dict);
-
+      status = zlib_inflate.inflateSetDictionary(this.strm, dictionary);
     }
 
     if (status === c.Z_BUF_ERROR && allowBufError === true) {

test/inflate.js

@@ -169,22 +169,44 @@ describe('Inflate with dictionary', function () {
 
   it('should throw on the wrong dictionary', function () {
     // var zCompressed = helpers.deflateSync('world', { dictionary: new Buffer('hello') });
-    var zCompressed = new Buffer([ 120, 187, 6, 44, 2, 21, 43, 207, 47, 202, 73, 1, 0, 6, 166, 2, 41 ]);
+    var zCompressed = new Uint8Array([ 120, 187, 6, 44, 2, 21, 43, 207, 47, 202, 73, 1, 0, 6, 166, 2, 41 ]);
 
     assert.throws(function () {
-      pako.inflate(zCompressed, { dictionary: new Buffer('world') });
+      pako.inflate(zCompressed, { dictionary: 'world' });
     }, /data error/);
   });
 
   it('trivial dictionary', function () {
-    var dict = new Buffer('abcdefghijklmnoprstuvwxyz');
+    var dict = 'abcdefghijklmnoprstuvwxyz';
     testInflate(samples, { dictionary: dict }, { dictionary: dict });
   });
 
   it('spdy dictionary', function () {
     var spdyDict = require('fs').readFileSync(require('path').join(__dirname, 'fixtures', 'spdy_dict.txt'));
-
-    testInflate(samples, { dictionary: spdyDict }, { dictionary: helpers.spdyDict });
+    testInflate(samples, { dictionary: spdyDict }, { dictionary: spdyDict });
   });
 
+  it('should throw if directory is not supplied to raw inflate', function () {
+    var dict = 'abcdefghijklmnoprstuvwxyz';
+    assert.throws(function () {
+      testInflate(samples, { raw: true }, { raw: true, dictionary: dict });
+    });
+  });
+
+  it('tests raw inflate with spdy dictionary', function () {
+    var spdyDict = require('fs').readFileSync(require('path').join(__dirname, 'fixtures', 'spdy_dict.txt'));
+    testInflate(samples, { raw: true, dictionary: spdyDict }, { raw: true, dictionary: spdyDict });
+  });
+
+  it('tests dictionary as Uint8Array', function () {
+    var dict = new Uint8Array(100);
+    for (var i = 0; i < 100; i++) dict[i] = Math.random() * 256;
+    testInflate(samples, { dictionary: dict }, { dictionary: dict });
+  });
+
+  it('tests dictionary as ArrayBuffer', function () {
+    var dict = new Uint8Array(100);
+    for (var i = 0; i < 100; i++) dict[i] = Math.random() * 256;
+    testInflate(samples, { dictionary: dict.buffer }, { dictionary: dict });
+  });
 });