add support for dependency tree rendering

package.json

@@ -29,8 +29,10 @@
     "test": "grunt test"
   },
   "dependencies": {
+    "archy": "^1.0.0",
     "bower": "^1.3.12",
     "bower-config": "^0.5.2",
+    "chalk": "^0.5.1",
     "inquirer": "^0.8.0",
     "mout": "^0.11.0"
   },

tasks/lib/GruntLogListener.js

@@ -8,7 +8,10 @@
 
 'use strict';
 
-var inquirer = require('inquirer');
+var archy = require('archy'),
+    chalk = require('chalk'),
+    inquirer = require('inquirer'),
+    mout = require('mout');
 
 var GruntLogListener = function (grunt) {
   this.grunt = grunt;
@@ -19,7 +22,12 @@ var GruntLogListener = function (grunt) {
   this.grunt.event.on('bower.prompt', this.prompt.bind(this));
 };
 
-GruntLogListener.prototype.end = function (data) {
+GruntLogListener.prototype.end = function (data, task) {
+  if (task === 'list') {
+    // print bower dependency tree if 'list' is the command
+    this.grunt.log.oklns("dependency tree:");
+    console.log(archy(tree2archy(data)));
+  }
   this.grunt.log.oklns("Bower command finished.");
 };
 
@@ -51,5 +59,69 @@ GruntLogListener.prototype.prompt = function (prompts, callback) {
   inquirer.prompt(prompts, callback);
 };
 
+/**
+ * the _tree2archy function, taken directly from bower source
+ * https://github.com/bower/bower/blob/master/lib/renderers/StandardRenderer.js#L424-480
+ *
+ * bower renderers are not a separate module, or else we wouldn't need this,
+ * see: https://github.com/bower/bower/issues/874
+ */
+function tree2archy (node) {
+  var dependencies = mout.object.values(node.dependencies);
+  var version = !node.missing ? node.pkgMeta._release || node.pkgMeta.version : null;
+  var label = node.endpoint.name + (version ? '#' + version : '');
+  var update;
+
+  if (node.root) {
+    label += ' ' + node.canonicalDir;
+  }
+
+  // State labels
+  if (node.missing) {
+    label += chalk.red(' not installed');
+    return label;
+  }
+
+  if (node.different) {
+    label += chalk.red(' different');
+  }
+
+  if (node.linked) {
+    label += chalk.magenta(' linked');
+  }
+
+  if (node.incompatible) {
+    label += chalk.yellow(' incompatible') + ' with ' + node.endpoint.target;
+  } else if (node.extraneous) {
+    label += chalk.green(' extraneous');
+  }
+
+  // New versions
+  if (node.update) {
+    update = '';
+
+    if (node.update.target && node.pkgMeta.version !== node.update.target) {
+        update += node.update.target + ' available';
+    }
+
+    if (node.update.latest !== node.update.target) {
+        update += (update ? ', ' : '');
+        update += 'latest is ' + node.update.latest;
+    }
+
+    if (update) {
+        label += ' (' + chalk.cyan(update) + ')';
+    }
+  }
+
+  if (!dependencies.length) {
+    return label;
+  }
+
+  return {
+    label: label,
+    nodes: mout.object.values(dependencies).map(tree2archy)
+  };
+}
 
 module.exports = GruntLogListener;