drop support for node < 4

.travis.yml

@@ -1,10 +1,7 @@
 language: node_js
-before_script:
-  - if [ "$TRAVIS_NODE_VERSION" = "0.10" ]; then npm i node-zlib-backport; fi
 after_success:
-  - if [ "$TRAVIS_NODE_VERSION" = "5" ]; then npm run coverage && npm i coveralls@2 && npm run coveralls; fi
+  - if [ "$TRAVIS_NODE_VERSION" = "6" ]; then npm run coverage && npm i coveralls@2 && npm run coveralls; fi
 node_js:
-  - "0.10"
-  - "0.12"
   - "4"
   - "5"
+  - "6"

README.md

@@ -22,8 +22,7 @@ Known lack of support for:
 Requirements
 ============
 
-* Async - Node.js 0.10 / 0.12 / IO.js
+* Node.js v4 (use older v2.3.0 for 0.10/0.12/iojs support)
-* Sync - Node.js 0.12 / IO.js (0.10 with [node-zlib-backport](https://www.npmjs.com/package/node-zlib-backport) dependency)
 
 Comparison Table
 ================
@@ -268,6 +267,9 @@ PNG.adjustGamma(png);
 Changelog
 ============
 
+### 3.0.0 - 03/08/2016
+ - Drop support for node below v4 and iojs. Pin to 2.3.0 to use with old, unsupported or patched node versions.
+
 ### 2.3.0 - 22/04/2016
  - Support for sync in node 0.10
 

appveyor.yml

@@ -5,7 +5,7 @@ clone_depth: 10
 environment:
   matrix:
     - nodejs_version: '4'
-    - nodejs_version: ''
+    - nodejs_version: '6'
 
 install:
   - ps: Install-Product node $env:nodejs_version

lib/packer-sync.js

@@ -2,22 +2,13 @@
 
 var hasSyncZlib = true;
 var zlib = require('zlib');
-if (!zlib.deflateSync) {
-  // Backwards compatibility with 0.10.
-  try {
-    zlib = require('node-zlib-backport');
-  }
-  catch(ex) {
-    hasSyncZlib = false;
-  }
-}
 var constants = require('./constants');
 var Packer = require('./packer');
 
 module.exports = function(metaData, opt) {
 
   if (!hasSyncZlib) {
-    throw new Error('To use the sync capability of this library in old node versions, please also add a dependency on node-zlb-backport');
+    throw new Error('To use the sync capability of this library in old node versions, please pin pngjs to v2.3.0');
   }
 
   var options = opt || {};

lib/parser-sync.js

@@ -2,15 +2,6 @@
 
 var hasSyncZlib = true;
 var zlib = require('zlib');
-if (!zlib.deflateSync) {
-  // Backwards compatibility with 0.10.
-  try {
-    zlib = require('node-zlib-backport');
-  }
-  catch(ex) {
-    hasSyncZlib = false;
-  }
-}
 var SyncReader = require('./sync-reader');
 var FilterSync = require('./filter-parse-sync');
 var Parser = require('./parser');
@@ -21,7 +12,7 @@ var formatNormaliser = require('./format-normaliser');
 module.exports = function(buffer, options) {
 
   if (!hasSyncZlib) {
-    throw new Error('To use the sync capability of this library in old node versions, please also add a dependency on node-zlb-backport');
+    throw new Error('To use the sync capability of this library in old node versions, please pin pngjs to v2.3.0');
   }
 
   var err;

package.json

@@ -1,6 +1,6 @@
 {
   "name": "pngjs",
-  "version": "2.3.1",
+  "version": "3.0.0",
   "description": "PNG encoder/decoder in pure JS, supporting any bit size & interlace, async & sync with full test suite.",
   "contributors": [
     "Alexandre Paré",
@@ -27,8 +27,7 @@
     "pngjs"
   ],
   "engines": {
-    "node": ">=0.10.0",
+    "node": ">=4.0.0"
-    "iojs": ">= 1.0.0"
   },
   "main": "./lib/png.js",
   "directories": {
@@ -53,7 +52,7 @@
     "buffer-equal": "1.0.0",
     "connect": "^3.4.0",
     "eslint": "^2.5.0",
-    "istanbul": "^0.4.1",
+    "istanbul": "^0.4.4",
     "phantomjs-prebuilt": "^2.1.7",
     "serve-static": "^1.10.0",
     "tap-dot": "^1.0.0",