diff --git a/Cakefile b/Cakefile
index b148ee54..0ffa9762 100644
--- a/Cakefile
+++ b/Cakefile
@@ -172,6 +172,7 @@ runTests = (CoffeeScript) ->
 
   # Convenience aliases.
   global.CoffeeScript = CoffeeScript
+  global.Repl = require './lib/coffee-script/repl'
 
   # Our test helper function for delimiting different test cases.
   global.test = (description, fn) ->
@@ -199,8 +200,8 @@ runTests = (CoffeeScript) ->
       return no for el, idx in a when not arrayEgal el, b[idx]
       yes
 
-  global.eq      = (a, b, msg) -> ok egal(a, b), msg
-  global.arrayEq = (a, b, msg) -> ok arrayEgal(a,b), msg
+  global.eq      = (a, b, msg) -> ok egal(a, b), msg ? "Expected #{a} to equal #{b}"
+  global.arrayEq = (a, b, msg) -> ok arrayEgal(a,b), msg ? "Expected #{a} to deep equal #{b}"
 
   # When all the tests have run, collect and print errors.
   # If a stacktrace is available, output the compiled function source.
diff --git a/lib/coffee-script/command.js b/lib/coffee-script/command.js
index 10ae763a..01667867 100644
--- a/lib/coffee-script/command.js
+++ b/lib/coffee-script/command.js
@@ -67,7 +67,7 @@
       loadRequires();
     }
     if (opts.interactive) {
-      return require('./repl');
+      return require('./repl').start();
     }
     if (opts.watch && !fs.watch) {
       return printWarn("The --watch feature depends on Node v0.6.0+. You are running " + process.version + ".");
@@ -79,7 +79,7 @@
       return compileScript(null, sources[0]);
     }
     if (!sources.length) {
-      return require('./repl');
+      return require('./repl').start();
     }
     literals = opts.run ? sources.splice(1) : [];
     process.argv = process.argv.slice(0, 2).concat(literals);
diff --git a/lib/coffee-script/repl.js b/lib/coffee-script/repl.js
index c14b8d1b..06f7f321 100644
--- a/lib/coffee-script/repl.js
+++ b/lib/coffee-script/repl.js
@@ -1,276 +1,104 @@
 // Generated by CoffeeScript 1.5.0-pre
 (function() {
-  var ACCESSOR, CoffeeScript, Module, REPL_PROMPT, REPL_PROMPT_CONTINUATION, REPL_PROMPT_MULTILINE, SIMPLEVAR, Script, autocomplete, backlog, completeAttribute, completeVariable, enableColours, error, getCompletions, inspect, multilineMode, pipedInput, readline, repl, run, stdin, stdout,
-    __indexOf = [].indexOf || function(item) { for (var i = 0, l = this.length; i < l; i++) { if (i in this && this[i] === item) return i; } return -1; };
+  var CoffeeScript, addMultilineHandler, merge, nodeREPL, replDefaults, vm;
 
-  stdin = process.openStdin();
+  vm = require('vm');
 
-  stdout = process.stdout;
+  nodeREPL = require('repl');
 
   CoffeeScript = require('./coffee-script');
 
-  readline = require('readline');
+  merge = require('./helpers').merge;
 
-  inspect = require('util').inspect;
-
-  Script = require('vm').Script;
-
-  Module = require('module');
-
-  REPL_PROMPT = 'coffee> ';
-
-  REPL_PROMPT_MULTILINE = '------> ';
-
-  REPL_PROMPT_CONTINUATION = '......> ';
-
-  enableColours = false;
-
-  if (process.platform !== 'win32') {
-    enableColours = !process.env.NODE_DISABLE_COLORS;
-  }
-
-  error = function(err) {
-    return stdout.write((err.stack || err.toString()) + '\n');
-  };
-
-  ACCESSOR = /\s*([\w\.]+)(?:\.(\w*))$/;
-
-  SIMPLEVAR = /(\w+)$/i;
-
-  autocomplete = function(text) {
-    return completeAttribute(text) || completeVariable(text) || [[], text];
-  };
-
-  completeAttribute = function(text) {
-    var all, candidates, completions, key, match, obj, prefix, _i, _len, _ref;
-    if (match = text.match(ACCESSOR)) {
-      all = match[0], obj = match[1], prefix = match[2];
+  replDefaults = {
+    prompt: 'coffee> ',
+    "eval": function(input, context, filename, cb) {
+      var js;
+      input = input.replace(/\uFF00/g, '\n');
+      input = input.replace(/(^|[\r\n]+)(\s*)##?(?:[^#\r\n][^\r\n]*|)($|[\r\n])/, '$1$2$3');
+      if (/^\s*$/.test(input)) {
+        return cb(null);
+      }
       try {
-        obj = Script.runInThisContext(obj);
-      } catch (e) {
-        return;
+        js = CoffeeScript.compile("_=(" + input + "\n)", {
+          filename: filename,
+          bare: true
+        });
+      } catch (err) {
+        cb(err);
       }
-      if (obj == null) {
-        return;
-      }
-      obj = Object(obj);
-      candidates = Object.getOwnPropertyNames(obj);
-      while (obj = Object.getPrototypeOf(obj)) {
-        _ref = Object.getOwnPropertyNames(obj);
-        for (_i = 0, _len = _ref.length; _i < _len; _i++) {
-          key = _ref[_i];
-          if (__indexOf.call(candidates, key) < 0) {
-            candidates.push(key);
-          }
-        }
-      }
-      completions = getCompletions(prefix, candidates);
-      return [completions, prefix];
+      return cb(null, vm.runInContext(js, context, filename));
     }
   };
 
-  completeVariable = function(text) {
-    var candidates, completions, free, key, keywords, r, vars, _i, _len, _ref;
-    free = (_ref = text.match(SIMPLEVAR)) != null ? _ref[1] : void 0;
-    if (text === "") {
-      free = "";
-    }
-    if (free != null) {
-      vars = Script.runInThisContext('Object.getOwnPropertyNames(Object(this))');
-      keywords = (function() {
-        var _i, _len, _ref1, _results;
-        _ref1 = CoffeeScript.RESERVED;
-        _results = [];
-        for (_i = 0, _len = _ref1.length; _i < _len; _i++) {
-          r = _ref1[_i];
-          if (r.slice(0, 2) !== '__') {
-            _results.push(r);
-          }
-        }
-        return _results;
-      })();
-      candidates = vars;
-      for (_i = 0, _len = keywords.length; _i < _len; _i++) {
-        key = keywords[_i];
-        if (__indexOf.call(candidates, key) < 0) {
-          candidates.push(key);
-        }
-      }
-      completions = getCompletions(free, candidates);
-      return [completions, free];
-    }
-  };
-
-  getCompletions = function(prefix, candidates) {
-    var el, _i, _len, _results;
-    _results = [];
-    for (_i = 0, _len = candidates.length; _i < _len; _i++) {
-      el = candidates[_i];
-      if (0 === el.indexOf(prefix)) {
-        _results.push(el);
-      }
-    }
-    return _results;
-  };
-
-  process.on('uncaughtException', error);
-
-  backlog = '';
-
-  run = function(buffer) {
-    var code, returnValue, _;
-    buffer = buffer.replace(/(^|[\r\n]+)(\s*)##?(?:[^#\r\n][^\r\n]*|)($|[\r\n])/, "$1$2$3");
-    buffer = buffer.replace(/[\r\n]+$/, "");
-    if (multilineMode) {
-      backlog += "" + buffer + "\n";
-      repl.setPrompt(REPL_PROMPT_CONTINUATION);
-      repl.prompt();
-      return;
-    }
-    if (!buffer.toString().trim() && !backlog) {
-      repl.prompt();
-      return;
-    }
-    code = backlog += buffer;
-    if (code[code.length - 1] === '\\') {
-      backlog = "" + backlog.slice(0, -1) + "\n";
-      repl.setPrompt(REPL_PROMPT_CONTINUATION);
-      repl.prompt();
-      return;
-    }
-    repl.setPrompt(REPL_PROMPT);
-    backlog = '';
-    try {
-      _ = global._;
-      returnValue = CoffeeScript["eval"]("_=(" + code + "\n)", {
-        filename: 'repl',
-        modulename: 'repl'
-      });
-      if (returnValue === void 0) {
-        global._ = _;
-      }
-      repl.output.write("" + (inspect(returnValue, false, 2, enableColours)) + "\n");
-    } catch (err) {
-      error(err);
-    }
-    return repl.prompt();
-  };
-
-  if (stdin.readable && stdin.isRaw) {
-    pipedInput = '';
-    repl = {
-      prompt: function() {
-        return stdout.write(this._prompt);
-      },
-      setPrompt: function(p) {
-        return this._prompt = p;
-      },
-      input: stdin,
-      output: stdout,
-      on: function() {}
+  addMultilineHandler = function(repl) {
+    var inputStream, multiline, nodeLineListener, outputStream, rli;
+    rli = repl.rli, inputStream = repl.inputStream, outputStream = repl.outputStream;
+    multiline = {
+      enabled: false,
+      initialPrompt: repl.prompt.replace(/^[^> ]*/, function(x) {
+        return x.replace(/./g, '-');
+      }),
+      prompt: repl.prompt.replace(/^[^> ]*>?/, function(x) {
+        return x.replace(/./g, '.');
+      }),
+      buffer: ''
     };
-    stdin.on('data', function(chunk) {
-      var line, lines, _i, _len, _ref;
-      pipedInput += chunk;
-      if (!/\n/.test(pipedInput)) {
+    nodeLineListener = rli.listeners('line')[0];
+    rli.removeListener('line', nodeLineListener);
+    rli.on('line', function(cmd) {
+      if (multiline.enabled) {
+        multiline.buffer += "" + cmd + "\n";
+        rli.setPrompt(multiline.prompt);
+        rli.prompt(true);
+      } else {
+        nodeLineListener(cmd);
+      }
+    });
+    return inputStream.on('keypress', function(char, key) {
+      if (!(key && key.ctrl && !key.meta && !key.shift && key.name === 'v')) {
         return;
       }
-      lines = pipedInput.split("\n");
-      pipedInput = lines[lines.length - 1];
-      _ref = lines.slice(0, -1);
-      for (_i = 0, _len = _ref.length; _i < _len; _i++) {
-        line = _ref[_i];
-        if (!(line)) {
-          continue;
+      if (multiline.enabled) {
+        if (!multiline.buffer.match(/\n/)) {
+          multiline.enabled = !multiline.enabled;
+          rli.setPrompt(repl.prompt);
+          rli.prompt(true);
+          return;
         }
-        stdout.write("" + line + "\n");
-        run(line);
+        if ((rli.line != null) && !rli.line.match(/^\s*$/)) {
+          return;
+        }
+        multiline.enabled = !multiline.enabled;
+        rli.line = '';
+        rli.cursor = 0;
+        rli.output.cursorTo(0);
+        rli.output.clearLine(1);
+        multiline.buffer = multiline.buffer.replace(/\n/g, '\uFF00');
+        rli.emit('line', multiline.buffer);
+        multiline.buffer = '';
+      } else {
+        multiline.enabled = !multiline.enabled;
+        rli.setPrompt(multiline.initialPrompt);
+        rli.prompt(true);
       }
     });
-    stdin.on('end', function() {
-      var line, _i, _len, _ref;
-      _ref = pipedInput.trim().split("\n");
-      for (_i = 0, _len = _ref.length; _i < _len; _i++) {
-        line = _ref[_i];
-        if (!(line)) {
-          continue;
-        }
-        stdout.write("" + line + "\n");
-        run(line);
+  };
+
+  module.exports = {
+    start: function(opts) {
+      var repl;
+      if (opts == null) {
+        opts = {};
       }
-      stdout.write('\n');
-      return process.exit(0);
-    });
-  } else {
-    if (readline.createInterface.length < 3) {
-      repl = readline.createInterface(stdin, autocomplete);
-      stdin.on('data', function(buffer) {
-        return repl.write(buffer);
+      opts = merge(replDefaults, opts);
+      repl = nodeREPL.start(opts);
+      repl.on('exit', function() {
+        return repl.outputStream.write('\n');
       });
-    } else {
-      repl = readline.createInterface(stdin, stdout, autocomplete);
+      addMultilineHandler(repl);
+      return repl;
     }
-  }
-
-  multilineMode = false;
-
-  repl.input.on('keypress', function(char, key) {
-    var cursorPos, newPrompt;
-    if (!(key && key.ctrl && !key.meta && !key.shift && key.name === 'v')) {
-      return;
-    }
-    cursorPos = repl.cursor;
-    repl.output.cursorTo(0);
-    repl.output.clearLine(1);
-    multilineMode = !multilineMode;
-    if (!multilineMode && backlog) {
-      repl._line();
-    }
-    backlog = '';
-    repl.setPrompt((newPrompt = multilineMode ? REPL_PROMPT_MULTILINE : REPL_PROMPT));
-    repl.prompt();
-    return repl.output.cursorTo(newPrompt.length + (repl.cursor = cursorPos));
-  });
-
-  repl.input.on('keypress', function(char, key) {
-    if (!(multilineMode && repl.line)) {
-      return;
-    }
-    if (!(key && key.ctrl && !key.meta && !key.shift && key.name === 'd')) {
-      return;
-    }
-    multilineMode = false;
-    return repl._line();
-  });
-
-  repl.on('attemptClose', function() {
-    if (multilineMode) {
-      multilineMode = false;
-      repl.output.cursorTo(0);
-      repl.output.clearLine(1);
-      repl._onLine(repl.line);
-      return;
-    }
-    if (backlog || repl.line) {
-      backlog = '';
-      repl.historyIndex = -1;
-      repl.setPrompt(REPL_PROMPT);
-      repl.output.write('\n(^C again to quit)');
-      return repl._line((repl.line = ''));
-    } else {
-      return repl.close();
-    }
-  });
-
-  repl.on('close', function() {
-    repl.output.write('\n');
-    return repl.input.destroy();
-  });
-
-  repl.on('line', run);
-
-  repl.setPrompt(REPL_PROMPT);
-
-  repl.prompt();
+  };
 
 }).call(this);
diff --git a/src/command.coffee b/src/command.coffee
index 8be84a41..cc10c06d 100644
--- a/src/command.coffee
+++ b/src/command.coffee
@@ -68,12 +68,12 @@ exports.run = ->
   return usage()                         if opts.help
   return version()                       if opts.version
   loadRequires()                         if opts.require
-  return require './repl'                if opts.interactive
+  return require('./repl').start()       if opts.interactive
   if opts.watch and !fs.watch
     return printWarn "The --watch feature depends on Node v0.6.0+. You are running #{process.version}."
   return compileStdio()                  if opts.stdio
   return compileScript null, sources[0]  if opts.eval
-  return require './repl'                unless sources.length
+  return require('./repl').start()       unless sources.length
   literals = if opts.run then sources.splice 1 else []
   process.argv = process.argv[0..1].concat literals
   process.argv[0] = 'coffee'
diff --git a/src/repl.coffee b/src/repl.coffee
index d94c63eb..c0855b43 100644
--- a/src/repl.coffee
+++ b/src/repl.coffee
@@ -1,197 +1,77 @@
-# A very simple Read-Eval-Print-Loop. Compiles one line at a time to JavaScript
-# and evaluates it. Good for simple tests, or poking around the **Node.js** API.
-# Using it looks like this:
-#
-#     coffee> console.log "#{num} bottles of beer" for num in [99..1]
-
-# Start by opening up `stdin` and `stdout`.
-stdin = process.openStdin()
-stdout = process.stdout
-
-# Require the **coffee-script** module to get access to the compiler.
+vm = require 'vm'
+nodeREPL = require 'repl'
 CoffeeScript = require './coffee-script'
-readline     = require 'readline'
-{inspect}    = require 'util'
-{Script}     = require 'vm'
-Module       = require 'module'
+{merge} = require './helpers'
 
-# REPL Setup
+replDefaults =
+  prompt: 'coffee> ',
+  eval: (input, context, filename, cb) ->
+    # XXX: multiline hack
+    input = input.replace /\uFF00/g, '\n'
+    # strip single-line comments
+    input = input.replace /(^|[\r\n]+)(\s*)##?(?:[^#\r\n][^\r\n]*|)($|[\r\n])/, '$1$2$3'
+    # empty command
+    return cb null if /^\s*$/.test input
+    # TODO: fix #1829: pass in-scope vars and avoid accidentally shadowing them by omitting those declarations
+    try
+      js = CoffeeScript.compile "_=(#{input}\n)", {filename, bare: yes}
+    catch err
+      cb err
+    cb null, vm.runInContext(js, context, filename)
 
-# Config
-REPL_PROMPT = 'coffee> '
-REPL_PROMPT_MULTILINE = '------> '
-REPL_PROMPT_CONTINUATION = '......> '
-enableColours = no
-unless process.platform is 'win32'
-  enableColours = not process.env.NODE_DISABLE_COLORS
+addMultilineHandler = (repl) ->
+  {rli, inputStream, outputStream} = repl
 
-# Log an error.
-error = (err) ->
-  stdout.write (err.stack or err.toString()) + '\n'
+  multiline =
+    enabled: off
+    initialPrompt: repl.prompt.replace(/^[^> ]*/, (x) -> x.replace /./g, '-')
+    prompt: repl.prompt.replace(/^[^> ]*>?/, (x) -> x.replace /./g, '.')
+    buffer: ''
 
-## Autocompletion
-
-# Regexes to match complete-able bits of text.
-ACCESSOR  = /\s*([\w\.]+)(?:\.(\w*))$/
-SIMPLEVAR = /(\w+)$/i
-
-# Returns a list of completions, and the completed text.
-autocomplete = (text) ->
-  completeAttribute(text) or completeVariable(text) or [[], text]
-
-# Attempt to autocomplete a chained dotted attribute: `one.two.three`.
-completeAttribute = (text) ->
-  if match = text.match ACCESSOR
-    [all, obj, prefix] = match
-    try obj = Script.runInThisContext obj
-    catch e
-      return
-    return unless obj?
-    obj = Object obj
-    candidates = Object.getOwnPropertyNames obj
-    while obj = Object.getPrototypeOf obj
-      for key in Object.getOwnPropertyNames obj when key not in candidates
-        candidates.push key
-    completions = getCompletions prefix, candidates
-    [completions, prefix]
-
-# Attempt to autocomplete an in-scope free variable: `one`.
-completeVariable = (text) ->
-  free = text.match(SIMPLEVAR)?[1]
-  free = "" if text is ""
-  if free?
-    vars = Script.runInThisContext 'Object.getOwnPropertyNames(Object(this))'
-    keywords = (r for r in CoffeeScript.RESERVED when r[..1] isnt '__')
-    candidates = vars
-    for key in keywords when key not in candidates
-      candidates.push key
-    completions = getCompletions free, candidates
-    [completions, free]
-
-# Return elements of candidates for which `prefix` is a prefix.
-getCompletions = (prefix, candidates) ->
-  el for el in candidates when 0 is el.indexOf prefix
-
-# Make sure that uncaught exceptions don't kill the REPL.
-process.on 'uncaughtException', error
-
-# The current backlog of multi-line code.
-backlog = ''
-
-# The main REPL function. **run** is called every time a line of code is entered.
-# Attempt to evaluate the command. If there's an exception, print it out instead
-# of exiting.
-run = (buffer) ->
-  # remove single-line comments
-  buffer = buffer.replace /(^|[\r\n]+)(\s*)##?(?:[^#\r\n][^\r\n]*|)($|[\r\n])/, "$1$2$3"
-  # remove trailing newlines
-  buffer = buffer.replace /[\r\n]+$/, ""
-  if multilineMode
-    backlog += "#{buffer}\n"
-    repl.setPrompt REPL_PROMPT_CONTINUATION
-    repl.prompt()
+  # Proxy node's line listener
+  nodeLineListener = rli.listeners('line')[0]
+  rli.removeListener 'line', nodeLineListener
+  rli.on 'line', (cmd) ->
+    if multiline.enabled
+      multiline.buffer += "#{cmd}\n"
+      rli.setPrompt multiline.prompt
+      rli.prompt true
+    else
+      nodeLineListener cmd
     return
-  if !buffer.toString().trim() and !backlog
-    repl.prompt()
+
+  # Handle Ctrl-v
+  inputStream.on 'keypress', (char, key) ->
+    return unless key and key.ctrl and not key.meta and not key.shift and key.name is 'v'
+    if multiline.enabled
+      # allow arbitrarily switching between modes any time before multiple lines are entered
+      unless multiline.buffer.match /\n/
+        multiline.enabled = not multiline.enabled
+        rli.setPrompt repl.prompt
+        rli.prompt true
+        return
+      # no-op unless the current line is empty
+      return if rli.line? and not rli.line.match /^\s*$/
+      # eval, print, loop
+      multiline.enabled = not multiline.enabled
+      rli.line = ''
+      rli.cursor = 0
+      rli.output.cursorTo 0
+      rli.output.clearLine 1
+      # XXX: multiline hack
+      multiline.buffer = multiline.buffer.replace /\n/g, '\uFF00'
+      rli.emit 'line', multiline.buffer
+      multiline.buffer = ''
+    else
+      multiline.enabled = not multiline.enabled
+      rli.setPrompt multiline.initialPrompt
+      rli.prompt true
     return
-  code = backlog += buffer
-  if code[code.length - 1] is '\\'
-    backlog = "#{backlog[...-1]}\n"
-    repl.setPrompt REPL_PROMPT_CONTINUATION
-    repl.prompt()
-    return
-  repl.setPrompt REPL_PROMPT
-  backlog = ''
-  try
-    _ = global._
-    returnValue = CoffeeScript.eval "_=(#{code}\n)", {
-      filename: 'repl'
-      modulename: 'repl'
-    }
-    if returnValue is undefined
-      global._ = _
-    repl.output.write "#{inspect returnValue, no, 2, enableColours}\n"
-  catch err
-    error err
-  repl.prompt()
 
-if stdin.readable and stdin.isRaw
-  # handle piped input
-  pipedInput = ''
-  repl =
-    prompt: -> stdout.write @_prompt
-    setPrompt: (p) -> @_prompt = p
-    input: stdin
-    output: stdout
-    on: ->
-  stdin.on 'data', (chunk) ->
-    pipedInput += chunk
-    return unless /\n/.test pipedInput
-    lines = pipedInput.split "\n"
-    pipedInput = lines[lines.length - 1]
-    for line in lines[...-1] when line
-      stdout.write "#{line}\n"
-      run line
-    return
-  stdin.on 'end', ->
-    for line in pipedInput.trim().split "\n" when line
-      stdout.write "#{line}\n"
-      run line
-    stdout.write '\n'
-    process.exit 0
-else
-  # Create the REPL by listening to **stdin**.
-  if readline.createInterface.length < 3
-    repl = readline.createInterface stdin, autocomplete
-    stdin.on 'data', (buffer) -> repl.write buffer
-  else
-    repl = readline.createInterface stdin, stdout, autocomplete
-
-multilineMode = off
-
-# Handle multi-line mode switch
-repl.input.on 'keypress', (char, key) ->
-  # test for Ctrl-v
-  return unless key and key.ctrl and not key.meta and not key.shift and key.name is 'v'
-  cursorPos = repl.cursor
-  repl.output.cursorTo 0
-  repl.output.clearLine 1
-  multilineMode = not multilineMode
-  repl._line() if not multilineMode and backlog
-  backlog = ''
-  repl.setPrompt (newPrompt = if multilineMode then REPL_PROMPT_MULTILINE else REPL_PROMPT)
-  repl.prompt()
-  repl.output.cursorTo newPrompt.length + (repl.cursor = cursorPos)
-
-# Handle Ctrl-d press at end of last line in multiline mode
-repl.input.on 'keypress', (char, key) ->
-  return unless multilineMode and repl.line
-  # test for Ctrl-d
-  return unless key and key.ctrl and not key.meta and not key.shift and key.name is 'd'
-  multilineMode = off
-  repl._line()
-
-repl.on 'attemptClose', ->
-  if multilineMode
-    multilineMode = off
-    repl.output.cursorTo 0
-    repl.output.clearLine 1
-    repl._onLine repl.line
-    return
-  if backlog or repl.line
-    backlog = ''
-    repl.historyIndex = -1
-    repl.setPrompt REPL_PROMPT
-    repl.output.write '\n(^C again to quit)'
-    repl._line (repl.line = '')
-  else
-    repl.close()
-
-repl.on 'close', ->
-  repl.output.write '\n'
-  repl.input.destroy()
-
-repl.on 'line', run
-
-repl.setPrompt REPL_PROMPT
-repl.prompt()
+module.exports =
+  start: (opts = {}) ->
+    opts = merge replDefaults, opts
+    repl = nodeREPL.start opts
+    repl.on 'exit', -> repl.outputStream.write '\n'
+    addMultilineHandler repl
+    repl
diff --git a/test/repl.coffee b/test/repl.coffee
index c683b32a..c08dc6c0 100644
--- a/test/repl.coffee
+++ b/test/repl.coffee
@@ -1,4 +1,80 @@
 # REPL
 # ----
+Stream = require 'stream'
 
-# TODO: add tests
+class MockInputStream extends Stream
+  constructor: ->
+    @readable = true
+
+  resume: ->
+
+  emitLine: (val) ->
+    @emit 'data', new Buffer("#{val}\n")
+
+class MockOutputStream extends Stream
+  constructor: ->
+    @writable = true
+    @written = []
+
+  write: (data) ->
+    #console.log 'output write', arguments
+    @written.push data
+
+  lastWrite: (fromEnd = -1) ->
+    @written[@written.length - 1 + fromEnd].replace /\n$/, ''
+
+
+testRepl = (desc, fn) ->
+  input = new MockInputStream
+  output = new MockOutputStream
+  Repl.start {input, output}
+  test desc, -> fn input, output
+
+ctrlV = { ctrl: true, name: 'v'}
+
+
+testRepl "starts with coffee prompt", (input, output) ->
+  eq 'coffee> ', output.lastWrite(0)
+
+testRepl "writes eval to output", (input, output) ->
+  input.emitLine '1+1'
+  eq '2', output.lastWrite()
+
+testRepl "comments are ignored", (input, output) ->
+  input.emitLine '1 + 1 #foo'
+  eq '2', output.lastWrite()
+
+testRepl "output in inspect mode", (input, output) ->
+  input.emitLine '"1 + 1\\n"'
+  eq "'1 + 1\\n'", output.lastWrite()
+
+testRepl "variables are saved", (input, output) ->
+  input.emitLine "foo = 'foo'"
+  input.emitLine 'foobar = "#{foo}bar"'
+  eq "'foobar'", output.lastWrite()
+
+testRepl "empty command evaluates to undefined", (input, output) ->
+  input.emitLine ''
+  eq 'undefined', output.lastWrite()
+
+testRepl "ctrl-v toggles multiline prompt", (input, output) ->
+  input.emit 'keypress', null, ctrlV
+  eq '------> ', output.lastWrite(0)
+  input.emit 'keypress', null, ctrlV
+  eq 'coffee> ', output.lastWrite(0)
+
+testRepl "multiline continuation changes prompt", (input, output) ->
+  input.emit 'keypress', null, ctrlV
+  input.emitLine ''
+  eq '....... ', output.lastWrite(0)
+
+testRepl "evaluates multiline", (input, output) ->
+  # Stubs. Could assert on their use.
+  output.cursorTo = (pos) ->
+  output.clearLine = ->
+
+  input.emit 'keypress', null, ctrlV
+  input.emitLine 'do ->'
+  input.emitLine '  1 + 1'
+  input.emit 'keypress', null, ctrlV
+  eq '2', output.lastWrite()
diff --git a/test/test.html b/test/test.html
index 256b2988..a09692c9 100644
--- a/test/test.html
+++ b/test/test.html
@@ -106,7 +106,6 @@
     'option_parser'
     'ranges'
     'regexps'
-    'repl'
     'scope'
     'slicing_and_splicing'
     'soaks'