diff --git a/package.json b/package.json
index 5f1db55..1cdfc94 100644
--- a/package.json
+++ b/package.json
@@ -4,7 +4,7 @@
   "description": "front-matter-editor help you to edit front-matter in markdown file ",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "mocha tests"
   },
   "repository": {
     "type": "git",
diff --git a/tests/front-matter-editor_tests.js b/tests/front-matter-editor_tests.js
index cf3a185..fc7a144 100644
--- a/tests/front-matter-editor_tests.js
+++ b/tests/front-matter-editor_tests.js
@@ -2,66 +2,147 @@
 
 const editor = require('../index');
 const path = require('path');
+const fs = require('fs');
 const extend = require('util')._extend;
+const chai = require('chai');
+
+const expect = chai.expect;
 
 describe('FrontMatterEditor tests', () =>{
   let filePath = path.join(__dirname, 'sample.md');
+  let file, originalPrintObject, printedObject;
 
-  it('show()', () => {
-    editor.read(filePath).show();
+  beforeEach(() => {
+      file = editor.read(filePath);
+      originalPrintObject = editor._printObject;
+      editor._printObject = (obj) => {
+          printedObject = obj;
+      };
   });
 
-  it("show('orig')", () => {
-    editor.read(filePath).show('orig');
+  afterEach(() => {
+      editor._printObject = originalPrintObject;
   });
 
-  it("show('data')", () => {
-    editor.read(filePath).show('data');
-  });
+  describe( 'show()', () => {
+      it('outputs all parts of parsed page', () => {
+        file.show();
+        expect(printedObject).to.deep.equal({
+            content: "\n# Abstract\n\nfront-matter-editor help you to edit front-matter in markdown of jekyll or included it.",
+            data: {
+                layout: 'post',
+                title: 'What is the front-matter-editor?'
+            },
+            orig: "---\nlayout: post\ntitle: What is the front-matter-editor?\n---\n\n# Abstract\n\nfront-matter-editor help you to edit front-matter in markdown of jekyll or included it."
+        });
+      });
 
-  it("show('content')", () => {
-    editor.read(filePath).show('content');
-  });
+      it('outputs only orig part of page with "orig" parameter', () => {
+          file.show('orig');
+          expect(printedObject).to.equal(
+              "---\nlayout: post\ntitle: What is the front-matter-editor?\n---\n\n# Abstract\n\nfront-matter-editor help you to edit front-matter in markdown of jekyll or included it."
+          );
+      });
 
-  it("data()", () => {
-    editor.read(filePath)
-      .show('data')
-      .data((data, matter) => {
-        matter.data = extend(data, {author: "saltfactory"});
-      })
-      .show('data');
-  });
+      it('outputs the front matter data with "data" parameter', () => {
+          file.show('data');
+          expect(printedObject).to.deep.equal({
+              layout: 'post',
+              title: 'What is the front-matter-editor?'
+          });
+      });
 
-  it("content()", () => {
-    editor.read(filePath)
-      .show('content')
-      .content((content, matter) => {
-        matter.content = `add content  ${content}`;
-      })
-      .show('content');
-  });
+      it('outputs only content part of page with "content" parameter', () => {
+          file.show('content');
+          expect(printedObject).to.equal(
+              "\n# Abstract\n\nfront-matter-editor help you to edit front-matter in markdown of jekyll or included it."
+          );
+      });
 
-  it("extend()", () => {
-    editor.read(filePath)
-      .show()
-      .extend((data, content, matter) => {
-        matter.data = extend(data, {author:'saltfactory'});
-        matter.content = `add Content ${content}`
-      })
-      .show();
-  });
+  } );
 
-  it("fileInfo()", () => {
-    editor.read(filePath)
-      .fileInfo();
-  });
+  describe( 'data()', () => {
+      it('can change the data with a callback', () => {
+          file.data((data, matter) => {
+              matter.data = extend(data, {author: 'saltfactory'});
+          }).show('data');
+          expect(printedObject).to.deep.equal({
+              layout: 'post',
+              title: 'What is the front-matter-editor?',
+              author: 'saltfactory'
+          });
+      });
 
-  it("save()", () => {
-    editor.read(filePath)
-      .data((data, matter) => matter.data.author = "saltfactory")
-      .save(path.join(__dirname, './'), {prefix:"2016-08-03-", postfix:".bak", filename:"abc.md"}, (err, matter) => {
-        console.log(matter);
+  } );
+
+  describe( 'content()', () => {
+      it('can change change the page content with a callback', () => {
+          file.content((content, matter) => {
+              matter.content = `add content  ${content}`;
+          }).show('content');
+          expect(printedObject).to.deep.equal(
+              "add content  \n# Abstract\n\nfront-matter-editor help you to edit front-matter in markdown of jekyll or included it."
+          );
+      });
+
+  } );
+
+  describe( 'extend()', () => {
+      it('can change change the front matter and page content with a callback', () => {
+          file.extend((data, content, matter) => {
+              matter.data = extend(data, {author: 'saltfactory'});
+              matter.content = `add content  ${content}`;
+          }).show();
+          expect(printedObject).to.deep.equal({
+              content: "add content  \n# Abstract\n\nfront-matter-editor help you to edit front-matter in markdown of jekyll or included it.",
+              data: {
+                  layout: 'post',
+                  title: 'What is the front-matter-editor?',
+                  author: 'saltfactory'
+              },
+              orig: "---\nlayout: post\ntitle: What is the front-matter-editor?\n---\n\n# Abstract\n\nfront-matter-editor help you to edit front-matter in markdown of jekyll or included it."
+          });
+      });
+
+  } );
+
+  describe( 'fileInfo()', () => {
+      it('outputs file metadata', () => {
+          file.fileInfo();
+          // spot check important properties
+          expect(printedObject.exists).to.equal(true);
+          expect(printedObject.flags.isFile).to.equal(true);
+          expect(printedObject.name).to.equal("sample.md");
+          expect(printedObject.extension).to.equal(".md");
       });
-  })
 
-});
\ No newline at end of file
+  } );
+
+  describe( 'save()', () => {
+      const expectedOutputPath = path.join(__dirname, './2016-08-03-abc.md.bak');
+
+      beforeEach(() => {
+          if (fs.existsSync(expectedOutputPath)) {
+              fs.unlinkSync(expectedOutputPath);
+          }
+      })
+
+      it('writes changes to specified file', (done) => {
+          // TODO use mock-fs to avoid writing to the real file system
+          file.data((data,matter) => {
+             matter.data = extend(data, {author: 'saltfactory'});
+          }).save(
+              path.join(__dirname, './'),
+              {prefix:"2016-08-03-", postfix:".bak", filename:"abc.md"},
+              (err, matter) => {
+                expect(err).to.equal(null);
+                expect(fs.existsSync(expectedOutputPath)).to.equal(true);
+                expect(fs.readFileSync(expectedOutputPath, 'utf8')).to.contain.string( "\nauthor: saltfactory")
+                done();
+              }
+          );
+      });
+
+  } );
+
+});