Adds Stream support for append()

lib/args.js

@@ -4,6 +4,7 @@
 
 var argsToArray = require('./utils').argsToArray;
 var isUtil = require('./utils').isUtil;
+var isReadableStream = require('./utils').isReadableStream;
 var tmp = require('tmp');
 var fs = require('fs');
 /**
@@ -95,12 +96,16 @@ module.exports = function (proto) {
               this._append.push(arg[j]);
             } else if (Buffer.isBuffer(arg[j])) {
               appendBuffer(this, arg[j]);
+            } else if (isReadableStream(arg)) {
+              appendStream(this, arg[j]);
             }
           }
           break;
         case 'object':
           if (Buffer.isBuffer(arg)) {
             appendBuffer(this, arg);
+          } else if (isReadableStream(arg)) {
+            appendStream(this, arg);
           }
           break;
       }
@@ -120,6 +125,31 @@ module.exports = function (proto) {
       
       return true;
     }
+    
+    function appendStream(self, stream) {
+      var tmpFileName = tmp.tmpNameSync();
+      
+      self._append.push(tmpFileName);
+      
+      var file = fs.createWriteStream(tmpFileName);
+      
+      self.preprocessor(function (callback) {
+        var finished = false;
+        
+        function ended(err) {
+          if (!finished) {
+            finished = true;
+            callback(err);
+          }
+        }
+        
+        file.on('finish', ended);
+
+        stream.pipe(file);
+      });
+      
+      return true;
+    }
 
     return this;
   }

lib/utils.js

@@ -1,3 +1,4 @@
+var stream = require('stream');
 
 /**
  * Escape the given shell `arg`.
@@ -40,4 +41,12 @@ exports.isUtil = function (v) {
 		break;
 	}
 	return ty;
+}
+
+var isStream = exports.isStream = function isStream(obj) {
+  return obj instanceof stream.Stream;
+}
+
+exports.isReadableStream = function isReadableStream(obj) {
+  return isStream(obj) && typeof obj._read == 'function' && typeof obj._readableState == 'object';
 }

test/appendStream.js

@@ -0,0 +1,78 @@
+var assert = require('assert')
+  , fs = require('fs')
+  , paths = require('path')
+  ;
+
+module.exports = function (_, dir, finish, gm) {
+  var out = paths.resolve(dir + '/appendBuffer.jpg');
+
+  try {
+    require('fs').unlinkSync(out);
+  } catch (_) {}
+
+  var buffer = fs.createReadStream(dir + '/original.jpg');
+  var buffer2 = fs.createReadStream(dir + '/original.jpg');
+  
+  var m = gm(dir + '/lost.png')
+  .append(dir + '/original.jpg')
+  .append(buffer, buffer2)
+  .append()
+  .background('#222')
+
+  var args = m.args();
+  assert.equal('convert', args[0]);
+  assert.equal('-background',args[1]);
+  assert.equal('#222',args[2]);
+  assert.ok(/examples\/imgs\/lost\.png$/.test(args[3]));
+  assert.ok(/examples\/imgs\/original\.jpg$/,args[4]);
+  assert.equal('-append',args[7]);
+  assert.equal('-',args[8]);
+
+  if (!gm.integration) {
+    return horizontal(dir, finish, gm);
+  }
+
+
+  m.write(out, function (err) {
+    if (err) return finish(err);
+    gm(out).size(function (err, size) {
+      if (err) return finish(err);
+      assert.equal(460, size.width);
+      assert.equal(590, size.height);
+
+      horizontal(dir, finish, gm);
+    })
+  });
+}
+
+function horizontal (dir, finish, gm) {
+  var out = paths.resolve(dir + '/appendBufferHorizontal.jpg');
+
+  var buffer = fs.createReadStream(dir + '/lost.png');
+
+  var m = gm(dir + '/original.jpg')
+  .append(buffer, true);
+
+  var args = m.args();
+  assert.equal('convert', args[0]);
+  assert.ok(/examples\/imgs\/original\.jpg$/.test(args[1]));
+  assert.equal('+append',args[3]);
+  assert.equal('-',args[4]);
+
+  if (!gm.integration) {
+    return finish();
+  }
+
+  m
+  .write(out, function (err) {
+    if (err) return finish(err);
+    gm(out).size(function (err, size) {
+      if (err) return finish(err);
+      assert.equal(697, size.width);
+      assert.equal(155, size.height);
+
+      finish();
+    })
+  });
+
+}