add log method to program object.

README.md

@@ -153,6 +153,10 @@ The screen on which every other node renders.
 - **tabSize** - the width of tabs within an element's content.
 - **autoPadding** - automatically position child elements with border and
   padding in mind.
+- **log** - create a log file. see `log` method.
+- **dump** - dump all output and input to desired file. can be used together
+  with `log` option if set as a boolean.
+- **debug** - debug mode. enables usage of the `debug` method.
 
 ##### Properties:
 
@@ -190,6 +194,9 @@ The screen on which every other node renders.
 ##### Methods:
 
 - inherits all from Node.
+- **log(msg, ...)** - write string to the log file if one was created.
+- **debug(msg, ...)** - same as the log method, but only gets called if the
+  `debug` option was set.
 - **alloc()** - allocate a new pending screen buffer and a new output screen
   buffer.
 - **draw(start, end)** - draw the screen based on the contents of the screen

lib/program.js

@@ -9,6 +9,7 @@
  */
 
 var EventEmitter = require('events').EventEmitter
+  , util = require('util')
   , Tput = require('./tput')
   , colors = require('./colors')
   , slice = Array.prototype.slice;
@@ -41,8 +42,10 @@ function Program(options) {
   this.input = options.input || process.stdin;
   this.output = options.output || process.stdout;
 
-  if (options.dump) {
-    this.dump(options.dump);
+  options.log = options.log || options.dump;
+  if (options.log) {
+    this._logger = require('fs').createWriteStream(options.log);
+    if (options.dump) this.setupDump();
   }
 
   this.zero = options.zero !== false;
@@ -76,12 +79,26 @@ function Program(options) {
 
 Program.prototype.__proto__ = EventEmitter.prototype;
 
-Program.prototype.dump = function(file) {
-  var self = this
-    , _write = this.output.write
-    , decoder = new (require('string_decoder')).StringDecoder('utf8');
+Program.prototype.log = function() {
+  return this._log('LOG',  util.format.apply(util, arguments));
+};
 
-  this.logger = require('fs').createWriteStream(file);
+Program.prototype.debug = function() {
+  if (!this.options.debug) return;
+  return this._log('DEBUG',  util.format.apply(util, arguments));
+};
+
+Program.prototype._log = function(pre, msg) {
+  if (!this._logger) return;
+  return this._logger.write(pre + ': ' + msg + '\n-\n');
+};
+
+Program.prototype.setupDump = function() {
+  var self = this
+    , write = this.output.write
+    , decoder;
+
+  decoder = new (require('string_decoder')).StringDecoder('utf8');
 
   function stringify(data) {
     return caret(data
@@ -139,14 +156,14 @@ Program.prototype.dump = function(file) {
     });
   }
 
-  this.output.write = function(data) {
-    self.logger.write('OUT: ' + stringify(data) + '\n-\n');
-    return _write.apply(this, arguments);
-  };
-
   this.input.on('data', function(data) {
-    self.logger.write('IN: ' + stringify(decoder.write(data)) + '\n-\n');
+    self._log('IN', stringify(decoder.write(data)));
   });
+
+  this.output.write = function(data) {
+    self._log('OUT', stringify(data));
+    return write.apply(this, arguments);
+  };
 };
 
 Program.prototype.setupTput = function() {

lib/widget.js

@@ -414,6 +414,14 @@ Screen.prototype.__proto__ = Node.prototype;
 
 Screen.prototype.type = 'screen';
 
+Screen.prototype.log = function() {
+  return this.program.log.apply(this.program, arguments);
+};
+
+Screen.prototype.debug = function() {
+  return this.program.debug.apply(this.program, arguments);
+};
+
 // TODO: Bubble and capture events throughout the tree.
 Screen.prototype._listenMouse = function(el) {
   var self = this;