Show review decision and reviewers in PR card

Review decisions and reviewers are not shown in PR card.

Showing review decions and reviewers will allow users to see what needs
to be done and which PRs require reviews at a glance, and showing 
reviewers allows tutors to gauge the level of PR reviews in the team.
Displaying an icon for PRs that have been merged without reviews can 
help tutors to easily identify PRs that violate best practices for 
software engineering.

Let's ,
* display review decions in the PR card,
* display the GitHub avatars of PR reviewers in the PR card,
* use tooltips to show information about reviews, and
* display an icon for PRs that have been merged without any review.

Author: wx-03

graphql/fragments/issue-model.fragment.graphql

@@ -22,5 +22,17 @@ fragment issueModel on Issue {
       }
     }
   }
+
   isDraft
+  reviewDecision
+  latestReviews(first: 100) {
+    edges {
+      node {
+        state
+        author {
+          ...reviewAuthor
+        }
+      }
+    }
+  }
 }

graphql/fragments/pullrequest.fragment.graphql

@@ -13,4 +13,5 @@ fragment pullrequest on PullRequest {
   milestone {
     ...issueMilestone
   }
+  reviewDecision
 }

graphql/fragments/review-author.fragment.graphql

@@ -0,0 +1,4 @@
+fragment reviewAuthor on Actor {
+  login
+  avatarUrl
+}

graphql/queries/fetch-pullrequests.graphql

@@ -20,6 +20,17 @@ query FetchPullRequests($owner: String!, $name: String!, $cursor: String) {
               }
             }
           }
+          latestReviews(first: 100) {
+            edges {
+              node {
+                state #PENDING/COMMENTED/APPROVED/CHANGES_REQUESTED/DISMISSED
+                author {
+                  ...reviewAuthor
+                }
+                createdAt
+              }
+            }
+          }
         }
       }
     }

graphql/schema/schema-extension.graphql

@@ -1,3 +1,5 @@
 extend type Issue {
   isDraft: Boolean
+  reviewDecision: String
+  latestReviews(first: Int): PullRequestReviewConnection
 }

src/app/core/models/github/github-graphql.issue-or-pr.ts

@@ -21,7 +21,9 @@ export class GithubGraphqlIssueOrPr extends GithubIssue {
       assignees: flattenEdges(issue.assignees.edges),
       labels: flattenEdges(issue.labels.edges),
       milestone: issue.milestone ? issue.milestone : null,
-      isDraft: issue.isDraft
+      isDraft: issue.isDraft,
+      reviewDecision: issue.reviewDecision,
+      reviews: issue.latestReviews ? flattenEdges(issue.latestReviews.edges) : null
     });
   }
 }

src/app/core/models/github/github-issue.model.ts

@@ -1,4 +1,6 @@
 import { IssueState, IssueStateReason } from '../../../../../graphql/graphql-types';
+import { ReviewDecision } from '../issue.model';
+import { PullrequestReviewState } from '../pullrequest-review.model';
 import { GithubComment } from './github-comment.model';
 import { GithubLabel } from './github-label.model';
 
@@ -30,6 +32,16 @@ export class GithubIssue {
   issueOrPr?: string;
   isDraft: boolean;
 
+  reviews?: Array<{
+    state: PullrequestReviewState;
+    author: {
+      login: string;
+      avatarUrl: string;
+    };
+  }>;
+
+  reviewDecision?: ReviewDecision | null;
+
   constructor(githubIssue: {}) {
     Object.assign(this, githubIssue);
     this.labels = [];

src/app/core/models/issue.model.ts

@@ -4,6 +4,13 @@ import { GithubIssue } from './github/github-issue.model';
 import { GithubLabel } from './github/github-label.model';
 import { HiddenData } from './hidden-data.model';
 import { Milestone } from './milestone.model';
+import { PullrequestReview } from './pullrequest-review.model';
+
+export enum ReviewDecision {
+  CHANGES_REQUESTED = 'CHANGES_REQUESTED',
+  APPROVED = 'APPROVED',
+  REVIEW_REQUIRED = 'REVIEW_REQUIRED'
+}
 
 export class Issue {
   /** Basic Fields */
@@ -28,6 +35,8 @@ export class Issue {
   assignees?: string[];
   labels?: string[];
   githubLabels?: GithubLabel[];
+  reviews?: PullrequestReview[];
+  reviewDecision?: ReviewDecision | null;
 
   /**
    * Formats the text to create space at the end of the user input to prevent any issues with
@@ -88,6 +97,7 @@ export class Issue {
     this.author = githubIssue.user.login;
     // this.githubIssue = githubIssue;
     this.isDraft = githubIssue.isDraft;
+    this.reviewDecision = githubIssue.reviewDecision;
 
     this.assignees = githubIssue.assignees.map((assignee) => assignee.login);
     this.githubLabels = githubIssue.labels;
@@ -97,6 +107,8 @@ export class Issue {
       : this.issueOrPr === 'Issue'
       ? Milestone.IssueWithoutMilestone
       : Milestone.PRWithoutMilestone;
+
+    this.reviews = githubIssue.reviews?.map((review) => new PullrequestReview(review));
   }
 
   public static createPhaseBugReportingIssue(githubIssue: GithubIssue): Issue {

src/app/core/models/pullrequest-review.model.ts

@@ -0,0 +1,40 @@
+export enum PullrequestReviewState {
+  PENDING = 'PENDING',
+  COMMENTED = 'COMMENTED',
+  APPROVED = 'APPROVED',
+  CHANGES_REQUESTED = 'CHANGES_REQUESTED',
+  DISMISSED = 'DISMISSED'
+}
+
+export class PullrequestReview {
+  state: PullrequestReviewState;
+  reviewer: string;
+  avatarUrl: string;
+
+  constructor(prReview: { state: PullrequestReviewState; author: { login: string; avatarUrl: string } }) {
+    this.state = prReview.state;
+    this.reviewer = prReview.author.login;
+    this.avatarUrl = prReview.author.avatarUrl;
+  }
+
+  /**
+   * Returns the required message to be shown in the tooltip for the review
+   * @returns Tooltip message as a string
+   */
+  public getReviewTooltipMessage(): string {
+    switch (this.state) {
+      case PullrequestReviewState.APPROVED:
+        return `${this.reviewer} approved`;
+      case PullrequestReviewState.CHANGES_REQUESTED:
+        return `${this.reviewer} requested changes`;
+      case PullrequestReviewState.COMMENTED:
+        return `${this.reviewer} commented in a review`;
+      case PullrequestReviewState.DISMISSED:
+        return `${this.reviewer}'s review was dismissed`;
+      case PullrequestReviewState.PENDING:
+        return `${this.reviewer} has a pending review`;
+      default:
+        return '';
+    }
+  }
+}