feature(comment): add list, get, edit and delete for issue comments

Author: Ray Hua

lib/Issue.js

@@ -44,6 +44,28 @@ class Issue extends Requestable {
       this._requestAllPages(`/repos/${this.__repository}/issues`, options, cb);
    }
 
+   /**
+    * List comments on an issue
+    * @see https://developer.github.com/v3/issues/comments/#list-comments-on-an-issue
+    * @param {number} issue - the id of the issue to get comments from
+    * @param {Requestable.callback} [cb] - will receive the comments
+    * @return {Promise} - the promise for the http request
+    */
+   listIssueComments(issue, cb) {
+      this._request('GET', `/repos/${this.__repository}/issues/${issue}/comments`, null, cb); // jscs:ignore
+   }
+
+   /**
+    * Get a single comment on an issue
+    * @see https://developer.github.com/v3/issues/comments/#get-a-single-comment
+    * @param {number} id - the comment id to get
+    * @param {Requestable.callback} [cb] - will receive the comment
+    * @return {Promise} - the promise for the http request
+    */
+   getIssueComment(id, cb) {
+      this._request('GET', `/repos/${this.__repository}/issues/comments/${id}`, null, cb); // jscs:ignore
+   }
+
    /**
     * Comment on an issue
     * @see https://developer.github.com/v3/issues/comments/#create-a-comment
@@ -56,6 +78,29 @@ class Issue extends Requestable {
       this._request('POST', `/repos/${this.__repository}/issues/${issue}/comments`, {body: comment}, cb); // jscs:ignore
    }
 
+   /**
+    * Edit a comment on an issue
+    * @see https://developer.github.com/v3/issues/comments/#edit-a-comment
+    * @param {number} id - the comment id to edit
+    * @param {string} comment - the comment to edit
+    * @param {Requestable.callback} [cb] - will receive the edited comment
+    * @return {Promise} - the promise for the http request
+    */
+   editIssueComment(id, comment, cb) {
+      this._request('PATCH', `/repos/${this.__repository}/issues/comments/${id}`, {body: comment}, cb); // jscs:ignore
+   }
+
+   /**
+    * Delete a comment on an issue
+    * @see https://developer.github.com/v3/issues/comments/#delete-a-comment
+    * @param {number} id - the comment id to delete
+    * @param {Requestable.callback} [cb] - will receive true if the request is successful
+    * @return {Promise} - the promise for the http request
+    */
+   deleteIssueComment(id, cb) {
+      this._request('DELETE', `/repos/${this.__repository}/issues/comments/${id}`, null, cb); // jscs:ignore
+   }
+
    /**
     * Edit an issue
     * @see https://developer.github.com/v3/issues/#edit-an-issue

test/issue.spec.js

@@ -8,6 +8,7 @@ describe('Issue', function() {
    let github;
    let remoteIssues;
    let remoteIssueId;
+   let remoteIssueCommentId;
 
    before(function() {
       github = new Github({
@@ -38,7 +39,7 @@ describe('Issue', function() {
       });
    });
 
-   describe('creating/modifiying', function() {
+   describe('creating/modifiying/editing/deleting', function() {
       // 200ms between tests so that Github has a chance to settle
       beforeEach(function(done) {
          setTimeout(done, 200);
@@ -67,6 +68,38 @@ describe('Issue', function() {
          }));
       });
 
+      it('should list issue comments', function(done) {
+         remoteIssues.listIssueComments(remoteIssueId, assertSuccessful(done, function(err, comments) {
+            expect(comments).to.be.an.array();
+            expect(comments[0]).to.have.own('body', 'Comment test');
+            remoteIssueCommentId = comments[0].id
+            done();
+         }));
+      });
+
+      it('should get a single issue comment', function(done) {
+         remoteIssues.getIssueComment(remoteIssueCommentId, assertSuccessful(done, function(err, comment) {
+            expect(comment).to.have.own('body', 'Comment test');
+            done();
+         }));
+      });
+
+      it('should edit issue comment', function(done) {
+         remoteIssues.editIssueComment(remoteIssueCommentId, 'Comment test edited', assertSuccessful(done, function(err, comment) {
+            expect(comment).to.have.own('body', 'Comment test edited');
+
+            done();
+         }));
+      });
+
+      it('should delete issue comment', function(done) {
+         remoteIssues.deleteIssueComment(remoteIssueCommentId, assertSuccessful(done, function(err, response) {
+            expect(response).to.be.true;
+
+            done();
+         }));
+      });
+
       it('should edit issues title', function(done) {
          const newProps = {
             title: 'Edited title'