Fix for issue #561 - Extend fs.access to support R_OK, W_OK, and X_OK (#601)

* added extended test for fs.access

* making requested changes

src/errors.js

@@ -7,7 +7,7 @@ var errors = {};
   //'0:OK:success',
   //'1:EOF:end of file',
   //'2:EADDRINFO:getaddrinfo error',
-  //'3:EACCES:permission denied',
+  '3:EACCES:permission denied',
   //'4:EAGAIN:resource temporarily unavailable',
   //'5:EADDRINUSE:address already in use',
   //'6:EADDRNOTAVAIL:address not available',

src/filesystem/implementation.js

@@ -439,15 +439,17 @@ function make_directory(context, path, callback) {
 
 function access_file(context, path, mode, callback) {
   path = normalize(path);
-  find_node(context, path, function (err) {
+  find_node(context, path, function (err, node) {
     if (err) {
       return callback(err);
     }
-    /* 
+    if(mode === Constants.F_OK){
-    TODO: we currently only support Constants.fsConstants.F_OK
+      return callback(null);
-    Working to fix the issue: https://github.com/filerjs/filer/issues/561
+    }
-    */
+    if (!(mode & Constants.X_OK) || (node.mode & (Constants.fsConstants.S_IXUSR | Constants.fsConstants.S_IXGRP | Constants.fsConstants.S_IXOTH))){
-    callback(null);
+      return callback(null);
+    }
+    callback(new Errors.EACCES('permission denied',path)) ; 
   });
 }
 
@@ -1687,7 +1689,7 @@ function access(fs, context, path, mode, callback) {
   }
 
   if (!pathCheck(path, callback)) return;
-  mode = mode | 0;
+  mode = mode | Constants.fsConstants.F_OK;
   access_file(context, path, mode, callback);
 }
 

tests/spec/fs.access.spec.js

@@ -20,7 +20,7 @@ describe('fs.access', function () {
     });
   });
 
-  it('should return no error if file does exist', function (done) {
+  it('should return no error if file does exist and mode = F_OK', function (done) {
     var fs = util.fs();
     var contents = 'This is a file.';
 
@@ -34,4 +34,97 @@ describe('fs.access', function () {
     });
   });
 
+  it('should return no error if file does exist and mode = R_OK', function (done) {
+    var fs = util.fs();
+    var contents = 'This is a file.';
+
+    fs.writeFile('/myfile', contents, function (error) {
+      if (error) throw error;
+
+      fs.access('/myfile', fs.constants.R_OK, function (error) {
+        expect(error).not.to.exist;
+        done();
+      });
+    });
+  });
+
+  it('should return no error if file does exist and mode = W_OK', function (done) {
+    var fs = util.fs();
+    var contents = 'This is a file.';
+   
+    fs.writeFile('/myfile', contents, function (error) {
+      if (error) throw error;
+
+      fs.access('/myfile', fs.constants.W_OK, function (error) {
+        expect(error).not.to.exist;
+        done();
+      });
+    });
+  });
+
+  // See bug https://github.com/filerjs/filer/issues/602
+  it.skip('should return an error if file is not executable and mode = X_OK', function (done) {
+    var fs = util.fs();
+    var contents = 'This is a file.';
+   
+    fs.writeFile('/myfile', contents, function (error) {
+      if (error) throw error;
+
+      fs.chmod('/myfile', 0o644, function(error){
+        if (error) throw error;
+      
+        fs.access('/myfile', fs.constants.X_OK, function (error) {
+          expect(error).to.exist;
+          expect(error.code).to.equal('EACCES');
+          done();
+        });  
+      });
+    });
+  });
+
+  it('should return no error if file does exist and mode = X_OK', function (done) {
+    var fs = util.fs();
+    var contents = 'This is a file.';
+   
+    fs.writeFile('/myfile', contents, function (error) {
+      if (error) throw error;
+
+      fs.chmod('/myfile', 0o777, function(error){
+        if (error) throw error;
+      
+        fs.access('/myfile', fs.constants.X_OK, function (error) {
+          expect(error).not.to.exist;
+          done();
+        });
+      });
+    });
+  });
+
+  it('should return no error if file does exist and no mode is passed', function (done) {
+    var fs = util.fs();
+    var contents = 'This is a file.';
+
+    fs.writeFile('/myfile', contents, function (error) {
+      if (error) throw error;
+
+      fs.access('/myfile', function (error) {
+        expect(error).not.to.exist;
+        done();
+      });
+    });
+  });
+
+  it('should return no error if file does exist and mode = R_OK | W_OK', function (done) {
+    var fs = util.fs();
+    var contents = 'This is a file.';
+   
+    fs.writeFile('/myfile', contents, function (error) {
+      if (error) throw error;
+
+      fs.access('/myfile', fs.constants.R_OK | fs.constants.W_OK, function (error) {
+        expect(error).not.to.exist;
+        done();
+      });
+    });
+  });
 });