Add a feature to optionally direct the test output to a file.

Makefile

@@ -4,6 +4,7 @@ TM_DEST = ~/Library/Application\ Support/TextMate/Bundles
 TM_BUNDLE = JavaScript\ mocha.tmbundle
 SRC = $(shell find lib -name "*.js" -type f | sort)
 SUPPORT = $(wildcard support/*.js)
+REPORTERS := $(shell bin/mocha --reporters | sed -e 's/ - .*//')
 
 all: mocha.js
 
@@ -33,7 +34,7 @@ lib-cov:
 
 test: test-unit
 
-test-all: test-bdd test-tdd test-qunit test-exports test-unit test-grep test-jsapi test-compilers test-glob
+test-all: test-bdd test-tdd test-qunit test-exports test-unit test-grep test-jsapi test-compilers test-glob test-reporter-output
 
 test-jsapi:
 	@node test/jsapi
@@ -104,6 +105,22 @@ test-async-only:
 test-glob:
 	@./test/acceptance/glob/glob.sh
 
+
+# The html reporter isn't supported at the command line
+TEST_REPORTERS := $(patsubst %,test-reporter-output-%,$(REPORTERS))
+TEST_REPORTERS := $(filter-out test-reporter-output-html,$(TEST_REPORTERS))
+
+.PHONY: $(REPORTERS)
+test-reporter-output: $(TEST_REPORTERS)
+test-reporter-output-%: %
+	@echo "Testing file output for reporter $<"
+	@./bin/mocha --no-color --reporter $< test/acceptance/interfaces/bdd 2>&1 > /tmp/$<.stdout
+	@./bin/mocha --no-color --reporter $< test/acceptance/interfaces/bdd -O /tmp/$<.file 2>&1 > /tmp/dot.file.stdout
+	@test -s /tmp/$<.file || \
+		(echo "ERROR: reporter $< does not support file output" && exit 1)
+	@test ! -s /tmp/$<.file.stdout || \
+		(echo "ERROR: reporter $< file output wrote to stdout" && exit 1)
+
 non-tty:
 	@./bin/mocha \
 		--reporter dot \

bin/_mocha

@@ -59,6 +59,7 @@ program
   .usage('[debug] [options] [files]')
   .option('-r, --require <name>', 'require the given module')
   .option('-R, --reporter <name>', 'specify the reporter to use', 'dot')
+  .option('-O, --output <file>', 'specify the output file', '-')
   .option('-u, --ui <name>', 'specify user-interface (bdd|tdd|exports)', 'bdd')
   .option('-g, --grep <pattern>', 'only run tests matching <pattern>')
   .option('-i, --invert', 'inverts --grep matches')
@@ -177,6 +178,10 @@ Error.stackTraceLimit = Infinity; // TODO: config
 
 mocha.reporter(program.reporter);
 
+// output
+
+mocha.output(program.output);
+
 // interface
 
 mocha.ui(program.ui);

lib/mocha.js

@@ -27,6 +27,7 @@ exports.reporters = require('./reporters');
 exports.Runnable = require('./runnable');
 exports.Context = require('./context');
 exports.Runner = require('./runner');
+exports.output = require('./output');
 exports.Suite = require('./suite');
 exports.Hook = require('./hook');
 exports.Test = require('./test');
@@ -70,6 +71,7 @@ function Mocha(options) {
   this.ui(options.ui);
   this.bail(options.bail);
   this.reporter(options.reporter);
+  this.output(options.output);
   if (options.timeout) this.timeout(options.timeout);
   if (options.slow) this.slow(options.slow);
 }
@@ -121,6 +123,17 @@ Mocha.prototype.reporter = function(reporter){
   return this;
 };
 
+/**
+ * Set output to `output`.
+ *
+ * @param {stream|String} target output stream, filename, or "-" for stdout
+ * @api public
+ */
+
+Mocha.prototype.output = function(target) {
+    this._output = exports.output.initialize(target);
+};
+
 /**
  * Set test UI `name`, defaults to "bdd".
  *
@@ -306,11 +319,14 @@ Mocha.prototype.run = function(fn){
   var suite = this.suite;
   var options = this.options;
   var runner = new exports.Runner(suite);
-  var reporter = new this._reporter(runner);
+  var reporter = new this._reporter(runner, this._output);
   runner.ignoreLeaks = false !== options.ignoreLeaks;
   runner.asyncOnly = options.asyncOnly;
   if (options.grep) runner.grep(options.grep, options.invert);
   if (options.globals) runner.globals(options.globals);
   if (options.growl) this._growl(runner, reporter);
-  return runner.run(fn);
+  var self = this;
+  return runner.run(function(errCount) {
+      exports.output.end(errCount, fn);
+  });
 };

lib/output.js

@@ -0,0 +1,78 @@
+var debug = require('debug')('mocha:output');
+var util = require('util');
+var fs = require('fs');
+var stream = require('stream');
+
+// Initialize in stdout mode
+var ostream = exports.ostream = process.stdout;
+
+/**
+ * Write preformatted output directly to the stream.
+ */
+exports.write = function(data) {
+    ostream.write(data);
+};
+
+
+/**
+ * Wrapper for log output.
+ */
+exports.log = function() {
+    if (ostream === process.stdout) {
+        console.log.apply(console, arguments);
+    } else {
+        ostream.write(util.format.apply(util, arguments) + "\n");
+    }
+};
+
+/**
+ * Wrapper for error output.
+ */
+exports.error = function() {
+    if (ostream === process.stdout) {
+        console.error.apply(console, arguments);
+    } else {
+        ostream.write(util.format.apply(util, arguments) + "\n");
+    }
+};
+
+/**
+ * Hook that's called when the test process is done to close the
+ * ostream ostream.
+ */
+exports.end = function(errCount, fn) {
+    if (ostream === process.stdout) {
+        // nothing to do
+        return fn(errCount);
+    }
+
+    ostream.end(function() { 
+        debug("ostream ended");
+        fn(errCount);
+
+        // Reset the ostream
+        ostream = process.stdout;
+    } );
+};
+
+/**
+ * Initialize the output module.
+ *
+ * If target is undefined or "-" then use stdout, otherwise open the
+ * target file.
+ */
+var initialize = exports.initialize = function(target) {
+    if (target === undefined) {
+        return ostream; // don't change
+    }
+
+    if (target === "-") {
+        ostream = exports.ostream = process.stdout;
+    } else if (target instanceof stream) {
+        ostream = exports.ostream = target;
+    } else {
+        ostream = exports.ostream = fs.createWriteStream(target);
+    }
+
+    return ostream;
+};

lib/reporters/base.js

@@ -5,7 +5,8 @@
 
 var tty = require('tty')
   , diff = require('diff')
-  , ms = require('../ms');
+  , ms = require('../ms')
+  , output = require('../output');
 
 /**
  * Save timer references to avoid Sinon interfering (see GH-237).
@@ -29,6 +30,12 @@ var isatty = tty.isatty(1) && tty.isatty(2);
 
 exports = module.exports = Base;
 
+/**
+ * Expose the output hooks
+ */
+exports.output = output;
+
+
 /**
  * Enable coloring by default.
  */
@@ -108,6 +115,7 @@ exports.window = {
     : 75
 };
 
+
 /**
  * Expose some basic cursor interactions
  * that are common among reporters.
@@ -144,7 +152,7 @@ exports.cursor = {
  */
 
 exports.list = function(failures){
-  console.error();
+  output.error();
   failures.forEach(function(test, i){
     // format
     var fmt = color('error title', '  %s) %s:\n')
@@ -206,7 +214,7 @@ exports.list = function(failures){
     stack = stack.slice(index ? index + 1 : index)
       .replace(/^/gm, '  ');
 
-    console.error(fmt, (i + 1), test.fullTitle(), msg, stack);
+    output.error(fmt, (i + 1), test.fullTitle(), msg, stack);
   });
 };
 
@@ -222,14 +230,17 @@ exports.list = function(failures){
  * @api public
  */
 
-function Base(runner) {
+function Base(runner, ostream) {
   var self = this
     , stats = this.stats = { suites: 0, tests: 0, passes: 0, pending: 0, failures: 0 }
     , failures = this.failures = [];
 
   if (!runner) return;
   this.runner = runner;
 
+  if (!ostream) return;
+  this.ostream = ostream;
+
   runner.stats = stats;
 
   runner.on('start', function(){
@@ -288,14 +299,14 @@ Base.prototype.epilogue = function(){
   var tests;
   var fmt;
 
-  console.log();
+  output.log();
 
   // passes
   fmt = color('bright pass', ' ')
     + color('green', ' %d passing')
     + color('light', ' (%s)');
 
-  console.log(fmt,
+  output.log(fmt,
     stats.passes || 0,
     ms(stats.duration));
 
@@ -304,21 +315,21 @@ Base.prototype.epilogue = function(){
     fmt = color('pending', ' ')
       + color('pending', ' %d pending');
 
-    console.log(fmt, stats.pending);
+    output.log(fmt, stats.pending);
   }
 
   // failures
   if (stats.failures) {
     fmt = color('fail', '  %d failing');
 
-    console.error(fmt,
+    output.error(fmt,
       stats.failures);
 
     Base.list(this.failures);
-    console.error();
+    output.error();
   }
 
-  console.log();
+  output.log();
 };
 
 /**

lib/reporters/doc.js

@@ -4,6 +4,7 @@
  */
 
 var Base = require('./base')
+  , output = Base.output
   , utils = require('../utils');
 
 /**
@@ -19,8 +20,8 @@ exports = module.exports = Doc;
  * @api public
  */
 
-function Doc(runner) {
-  Base.call(this, runner);
+function Doc(runner, ostream) {
+  Base.call(this, runner, ostream);
 
   var self = this
     , stats = this.stats
@@ -34,23 +35,23 @@ function Doc(runner) {
   runner.on('suite', function(suite){
     if (suite.root) return;
     ++indents;
-    console.log('%s<section class="suite">', indent());
+    output.log('%s<section class="suite">', indent());
     ++indents;
-    console.log('%s<h1>%s</h1>', indent(), utils.escape(suite.title));
-    console.log('%s<dl>', indent());
+    output.log('%s<h1>%s</h1>', indent(), utils.escape(suite.title));
+    output.log('%s<dl>', indent());
   });
 
   runner.on('suite end', function(suite){
     if (suite.root) return;
-    console.log('%s</dl>', indent());
+    output.log('%s</dl>', indent());
     --indents;
-    console.log('%s</section>', indent());
+    output.log('%s</section>', indent());
     --indents;
   });
 
   runner.on('pass', function(test){
-    console.log('%s  <dt>%s</dt>', indent(), utils.escape(test.title));
+    output.log('%s  <dt>%s</dt>', indent(), utils.escape(test.title));
     var code = utils.escape(utils.clean(test.fn.toString()));
-    console.log('%s  <dd><pre><code>%s</code></pre></dd>', indent(), code);
+    output.log('%s  <dd><pre><code>%s</code></pre></dd>', indent(), code);
   });
 }