Add support to pre-filed answers. (#901)

* Remove callback parameter that doesn't exists on prompt

* Remove node 8 test from travis

* Allow answer to be pre-filed.

* Implement askAnswered option

Co-authored-by: Simon Boudrias <admin@simonboudrias.com>

README.md

@@ -136,6 +136,7 @@ A question object is a `hash` containing question related values:
 - **pageSize**: (Number) Change the number of lines that will be rendered when using `list`, `rawList`, `expand` or `checkbox`.
 - **prefix**: (String) Change the default _prefix_ message.
 - **suffix**: (String) Change the default _suffix_ message.
+- **askAnswered**: (Boolean) Force to prompt the question if the answer already exists.
 
 `default`, `choices`(if defined as functions), `validate`, `filter` and `when` functions can be called asynchronously. Either return a promise or use `this.async()` to get a callback you'll call with the final value.
 

packages/inquirer/lib/inquirer.js

@@ -23,14 +23,14 @@ inquirer.ui = {
  * Create a new self-contained prompt module.
  */
 inquirer.createPromptModule = function(opt) {
-  var promptModule = function(questions) {
+  var promptModule = function(questions, answers) {
     var ui;
     try {
       ui = new inquirer.ui.Prompt(promptModule.prompts, opt);
     } catch (error) {
       return Promise.reject(error);
     }
-    var promise = ui.run(questions);
+    var promise = ui.run(questions, answers);
 
     // Monkey patch the UI on the promise object so
     // that it remains publicly accessible.

packages/inquirer/lib/ui/prompt.js

@@ -16,9 +16,13 @@ class PromptUI extends Base {
     this.prompts = prompts;
   }
 
-  run(questions) {
+  run(questions, answers) {
     // Keep global reference to the answers
-    this.answers = {};
+    if (_.isPlainObject(answers)) {
+      this.answers = _.clone(answers);
+    } else {
+      this.answers = {};
+    }
 
     // Make sure questions is an array.
     if (_.isPlainObject(questions)) {
@@ -40,9 +44,9 @@ class PromptUI extends Base {
     return this.process
       .pipe(
         reduce((answers, answer) => {
-          _.set(this.answers, answer.name, answer.answer);
-          return this.answers;
-        }, {})
+          _.set(answers, answer.name, answer.answer);
+          return answers;
+        }, this.answers)
       )
       .toPromise(Promise)
       .then(this.onCompletion.bind(this));
@@ -100,6 +104,10 @@ class PromptUI extends Base {
   }
 
   filterIfRunnable(question) {
+    if (question.askAnswered !== true && this.answers[question.name] !== undefined) {
+      return empty();
+    }
+
     if (question.when === false) {
       return empty();
     }

packages/inquirer/test/specs/inquirer.js

@@ -197,7 +197,7 @@ describe('inquirer.prompt', function() {
       }
     ];
 
-    var promise = this.prompt(prompts, function() {});
+    var promise = this.prompt(prompts);
     promise.ui.rl.emit('line');
   });
 
@@ -232,7 +232,7 @@ describe('inquirer.prompt', function() {
       }
     ];
 
-    var promise = this.prompt(prompts, function() {});
+    var promise = this.prompt(prompts);
     promise.ui.rl.emit('line');
   });
 
@@ -330,7 +330,7 @@ describe('inquirer.prompt', function() {
       }
     ];
 
-    var promise = this.prompt(prompts, function() {});
+    var promise = this.prompt(prompts);
     promise.ui.rl.emit('line');
   });
 
@@ -383,7 +383,7 @@ describe('inquirer.prompt', function() {
   });
 
   it('should expose the UI', function(done) {
-    var promise = this.prompt([], function() {});
+    var promise = this.prompt([]);
     expect(promise.ui.answers).to.be.an('object');
     done();
   });
@@ -417,6 +417,25 @@ describe('inquirer.prompt', function() {
     });
   });
 
+  it('should take a prompts array and answers and return answers', function() {
+    var prompts = [
+      {
+        type: 'confirm',
+        name: 'q1',
+        message: 'message'
+      }
+    ];
+
+    var answers = { prefiled: true };
+    var promise = this.prompt(prompts, answers);
+    autosubmit(promise.ui);
+
+    return promise.then(answers => {
+      expect(answers.prefiled).to.equal(true);
+      expect(answers.q1).to.equal(true);
+    });
+  });
+
   describe('hierarchical mode (`when`)', function() {
     it('should pass current answers to `when`', function() {
       var prompts = [
@@ -616,6 +635,52 @@ describe('inquirer.prompt', function() {
         expect(answers.q).to.equal('foo');
       });
     });
+
+    it('should not run prompt if answer exists for question', function() {
+      var throwFunc = function(step) {
+        throw new Error(`askAnswered Error ${step}`);
+      };
+      var prompts = [
+        {
+          type: 'input',
+          name: 'prefiled',
+          when: throwFunc.bind(undefined, 'when'),
+          validate: throwFunc.bind(undefined, 'validate'),
+          transformer: throwFunc.bind(undefined, 'transformer'),
+          filter: throwFunc.bind(undefined, 'filter'),
+          message: 'message',
+          default: 'newValue'
+        }
+      ];
+
+      var answers = { prefiled: 'prefiled' };
+      var promise = this.prompt(prompts, answers);
+      autosubmit(promise.ui);
+
+      return promise.then(answers => {
+        expect(answers.prefiled).to.equal('prefiled');
+      });
+    });
+
+    it('should run prompt if answer exists for question and askAnswered is set', function() {
+      var prompts = [
+        {
+          askAnswered: true,
+          type: 'input',
+          name: 'prefiled',
+          message: 'message',
+          default: 'newValue'
+        }
+      ];
+
+      var answers = { prefiled: 'prefiled' };
+      var promise = this.prompt(prompts, answers);
+      autosubmit(promise.ui);
+
+      return promise.then(answers => {
+        expect(answers.prefiled).to.equal('newValue');
+      });
+    });
   });
 
   describe('#registerPrompt()', function() {
@@ -628,7 +693,7 @@ describe('inquirer.prompt', function() {
         done();
       });
 
-      inquirer.prompt(questions, _.noop);
+      inquirer.prompt(questions);
     });
 
     it('overwrite default prompt types', function(done) {
@@ -638,7 +703,7 @@ describe('inquirer.prompt', function() {
         done();
       });
 
-      inquirer.prompt(questions, _.noop);
+      inquirer.prompt(questions);
       inquirer.restoreDefaultPrompts();
     });
   });