Add support for shell.env, PWD, TMP, and tempDir, with tests

src/shell.js

@@ -8,18 +8,45 @@ define(function(require) {
   function Shell(fs, options) {
     options = options || {};
 
+    var env = options.env || {};
+    env.TMP = env.TMP || '/tmp';
+    env.PATH = env.PATH || '';
+
     var cwd = '/';
 
+    /**
+     * The bound FileSystem (cannot be changed)
+     */
     Object.defineProperty(this, 'fs', {
       get: function() { return fs; },
       enumerable: true
     });
 
+    /**
+     * The current working directory (changed with `cd()`)
+     */
     Object.defineProperty(this, 'cwd', {
       get: function() { return cwd; },
       enumerable: true
     });
 
+    /**
+     * Support bash's $PWD on the env
+     */
+    Object.defineProperty(env, 'PWD', {
+      get: function() { return cwd; },
+      enumerable: true
+    });
+
+    /**
+     * The shell's environment (e.g., for things like
+     * path, tmp, and other env vars)
+     */
+    Object.defineProperty(this, 'env', {
+      get: function() { return env; },
+      enumerable: true
+    });
+
     // We include `cd` on the this vs. proto so that
     // we can access cwd without exposing it externally.
     this.cd = function(path, callback) {
@@ -242,6 +269,13 @@ define(function(require) {
     list(dir, callback);
   };
 
+  /**
+   * Removes the file or directory at `path`. If `path` is a file
+   * it will be removed. If `path` is a directory, it will be
+   * removed if it is empty, otherwise the callback will receive
+   * an error. In order to remove non-empty directories, use the
+   * `recursive=true` option.
+   */
   Shell.prototype.rm = function(path, options, callback) {
     var fs = this.fs;
     if(typeof options === 'function') {
@@ -308,6 +342,23 @@ define(function(require) {
     remove(path, callback);
   };
 
+  /**
+   * Gets the path to the temporary directory, creating it if not
+   * present. The directory used is the one specified in
+   * env.TMP. The callback receives (error, tempDirName).
+   */
+  Shell.prototype.tempDir = function(callback) {
+    var fs = this.fs;
+    var tmp = this.env.TMP;
+    callback = callback || function(){};
+
+    // Try and create it, and it will either work or fail
+    // but either way it's now there.
+    fs.mkdir(tmp, function(err) {
+      callback(null, tmp);
+    });
+  };
+
   return Shell;
 
 });

tests/lib/test-utils.js

@@ -68,8 +68,8 @@ function(Filer, IndexedDBTestProvider, WebSQLTestProvider, MemoryTestProvider) {
     return _provider;
   }
 
-  function shell() {
+  function shell(options) {
-    return fs().Shell();
+    return fs().Shell(options);
   }
 
   function cleanup(callback) {

tests/spec/shell/env.spec.js

@@ -0,0 +1,113 @@
+define(["Filer", "util"], function(Filer, util) {
+
+  describe('FileSystemShell.env', function() {
+    beforeEach(util.setup);
+    afterEach(util.cleanup);
+
+    it('should get default env options', function() {
+      var shell = util.shell();
+      expect(shell.env).to.exist;
+      expect(shell.env.TMP).to.equal('/tmp');
+      expect(shell.env.PATH).to.equal('');
+      expect(shell.env.PWD).to.equal('/');
+    });
+
+    it('should be able to specify env options', function() {
+      var options = {
+        env: {
+          TMP: '/tempdir',
+          PATH: '/dir'
+        }
+      };
+      var shell = util.shell(options);
+      expect(shell.env).to.exist;
+      expect(shell.env.TMP).to.equal('/tempdir');
+      expect(shell.env.PATH).to.equal('/dir');
+      expect(shell.env.PWD).to.equal('/');
+    });
+
+    it('should fail when dirs argument is absent', function(done) {
+      var fs = util.fs();
+      var shell = fs.Shell();
+
+      shell.cat(null, function(error, list) {
+        expect(error).to.exist;
+        expect(list).not.to.exist;
+        done();
+      });
+    });
+
+    it('should update the value of env.PWD when cwd changes', function(done) {
+      var fs = util.fs();
+      var shell = fs.Shell();
+
+      fs.mkdir('/dir', function(err) {
+        if(err) throw err;
+
+        expect(shell.cwd).to.equal('/');
+        expect(shell.env.PWD).to.equal('/');
+
+        shell.cd('/dir', function(err) {
+          expect(err).not.to.exist;
+          expect(shell.cwd).to.equal('/dir');
+          expect(shell.env.PWD).to.equal('/dir');
+          done();
+        });
+      });
+    });
+
+    it('should create/return the default tmp dir', function(done) {
+      var fs = util.fs();
+      var shell = fs.Shell();
+
+      expect(shell.env.TMP).to.equal('/tmp');
+      shell.tempDir(function(err, tmp) {
+        expect(err).not.to.exist;
+        shell.cd(tmp, function(err) {
+          expect(err).not.to.exist;
+          expect(shell.cwd).to.equal('/tmp');
+          expect(shell.env.PWD).to.equal('/tmp');
+          done();
+        });
+      });
+    });
+
+    it('should create/return the tmp dir specified in env.TMP', function(done) {
+      var fs = util.fs();
+      var shell = fs.Shell({
+        env: {
+          TMP: '/tempdir'
+        }
+      });
+
+      expect(shell.env.TMP).to.equal('/tempdir');
+      shell.tempDir(function(err, tmp) {
+        expect(err).not.to.exist;
+        shell.cd(tmp, function(err) {
+          expect(err).not.to.exist;
+          expect(shell.cwd).to.equal('/tempdir');
+          expect(shell.env.PWD).to.equal('/tempdir');
+          done();
+        });
+      });
+    });
+
+    it('should allow repeated calls to tempDir()', function(done) {
+      var fs = util.fs();
+      var shell = fs.Shell();
+
+      expect(shell.env.TMP).to.equal('/tmp');
+      shell.tempDir(function(err, tmp) {
+        expect(err).not.to.exist;
+        expect(tmp).to.equal('/tmp');
+
+        shell.tempDir(function(err, tmp) {
+          expect(err).not.to.exist;
+          expect(tmp).to.equal('/tmp');
+          done();
+        });
+      });
+    });
+
+  });
+});

tests/test-manifest.js

@@ -49,6 +49,7 @@ define([
   "spec/shell/cat.spec",
   "spec/shell/ls.spec",
   "spec/shell/rm.spec",
+  "spec/shell/env.spec",
 
   // Ported node.js tests (filenames match names in https://github.com/joyent/node/tree/master/test)
   "spec/node-js/simple/test-fs-mkdir",