Add PR reviews and comments to GitHub api (#179)

Also, a slight re-organization of the GitHub api test code.

src/plugins/github/__snapshots__/api.test.js.snap

@@ -1,8 +1,8 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`GitHub porcelain API Author 1`] = `2`;
+exports[`GitHub porcelain API has wrappers for Authors 1`] = `2`;
 
-exports[`GitHub porcelain API Author 2`] = `
+exports[`GitHub porcelain API has wrappers for Authors 2`] = `
 Object {
   "address": Object {
     "id": "https://github.com/decentralion",
@@ -18,9 +18,9 @@ Object {
 }
 `;
 
-exports[`GitHub porcelain API Comment 1`] = `3`;
+exports[`GitHub porcelain API has wrappers for Comments 1`] = `3`;
 
-exports[`GitHub porcelain API Comment 2`] = `
+exports[`GitHub porcelain API has wrappers for Comments 2`] = `
 Object {
   "address": Object {
     "id": "https://github.com/sourcecred/example-repo/issues/6#issuecomment-373768442",
@@ -35,7 +35,7 @@ Object {
 }
 `;
 
-exports[`GitHub porcelain API Issue 1`] = `
+exports[`GitHub porcelain API has wrappers for Issues 1`] = `
 Object {
   "address": Object {
     "id": "https://github.com/sourcecred/example-repo/issues/1",
@@ -52,7 +52,7 @@ Object {
 }
 `;
 
-exports[`GitHub porcelain API PullRequest 1`] = `
+exports[`GitHub porcelain API has wrappers for PullRequests 1`] = `
 Object {
   "address": Object {
     "id": "https://github.com/sourcecred/example-repo/pull/3",

src/plugins/github/api.js

@@ -11,6 +11,9 @@ import type {
   NodeType,
   IssueNodePayload,
   PullRequestNodePayload,
+  PullRequestReviewNodePayload,
+  PullRequestReviewCommentNodePayload,
+  PullRequestReviewState,
   CommentNodePayload,
   AuthorNodePayload,
   AuthorSubtype,
@@ -23,9 +26,17 @@ import {
   AUTHOR_NODE_TYPE,
   ISSUE_NODE_TYPE,
   PULL_REQUEST_NODE_TYPE,
+  PULL_REQUEST_REVIEW_NODE_TYPE,
+  PULL_REQUEST_REVIEW_COMMENT_NODE_TYPE,
 } from "./types";
 
-export type Entity = Issue | PullRequest | Comment | Author;
+export type Entity =
+  | Issue
+  | PullRequest
+  | Comment
+  | Author
+  | PullRequestReview
+  | PullRequestReviewComment;
 
 function assertEntityType(e: Entity, t: NodeType) {
   if (e.type() !== t) {
@@ -105,7 +116,12 @@ class GithubEntity<T: NodePayload> {
 }
 
 class Post<
-  T: IssueNodePayload | PullRequestNodePayload | CommentNodePayload
+  T:
+    | IssueNodePayload
+    | PullRequestNodePayload
+    | CommentNodePayload
+    | PullRequestReviewNodePayload
+    | PullRequestReviewCommentNodePayload
 > extends GithubEntity<T> {
   authors(): Author[] {
     return this.graph
@@ -159,6 +175,14 @@ export class PullRequest extends Commentable<PullRequestNodePayload> {
   title(): string {
     return this.node().payload.title;
   }
+  reviews(): PullRequestReview[] {
+    return this.graph
+      .neighborhood(this.nodeAddress, {
+        edgeType: CONTAINS_EDGE_TYPE,
+        nodeType: PULL_REQUEST_REVIEW_NODE_TYPE,
+      })
+      .map(({neighbor}) => new PullRequestReview(this.graph, neighbor));
+  }
 }
 
 export class Issue extends Commentable<IssueNodePayload> {
@@ -180,3 +204,31 @@ export class Comment extends Post<CommentNodePayload> {
     return (e: any);
   }
 }
+
+export class PullRequestReview extends Post<PullRequestReviewNodePayload> {
+  static from(e: Entity): PullRequestReview {
+    assertEntityType(e, PULL_REQUEST_REVIEW_NODE_TYPE);
+    return (e: any);
+  }
+  state(): PullRequestReviewState {
+    return this.node().payload.state;
+  }
+
+  comments(): PullRequestReviewComment[] {
+    return this.graph
+      .neighborhood(this.nodeAddress, {
+        edgeType: CONTAINS_EDGE_TYPE,
+        nodeType: PULL_REQUEST_REVIEW_COMMENT_NODE_TYPE,
+      })
+      .map(({neighbor}) => new PullRequestReviewComment(this.graph, neighbor));
+  }
+}
+
+export class PullRequestReviewComment extends Post<
+  PullRequestReviewCommentNodePayload
+> {
+  static from(e: Entity): PullRequestReviewComment {
+    assertEntityType(e, PULL_REQUEST_REVIEW_COMMENT_NODE_TYPE);
+    return (e: any);
+  }
+}

src/plugins/github/api.test.js

@@ -19,8 +19,8 @@ describe("GitHub porcelain API", () => {
     }
     return result;
   }
-
+  describe("has wrappers for", () => {
-  it("Issue", () => {
+    it("Issues", () => {
       const issue = issueOrPRByNumber(1);
       expect(issue.title()).toBe("An example issue.");
       expect(issue.body()).toBe("This is just an example issue.");
@@ -34,9 +34,10 @@ describe("GitHub porcelain API", () => {
       expect(issue.authors().map((x) => x.login())).toEqual(["decentralion"]);
     });
 
-  it("PullRequest", () => {
+    it("PullRequests", () => {
       const pullRequest = issueOrPRByNumber(3);
       expect(pullRequest.body()).toBe("Oh look, it's a pull request.");
+      expect(pullRequest.title()).toBe("Add README, merge via PR.");
       expect(pullRequest.url()).toBe(
         "https://github.com/sourcecred/example-repo/pull/3"
       );
@@ -46,7 +47,29 @@ describe("GitHub porcelain API", () => {
       expect(pullRequest.address()).toEqual(pullRequest.node().address);
     });
 
-  it("Comment", () => {
+    it("Pull Request Reviews", () => {
+      const pr = PullRequest.from(issueOrPRByNumber(5));
+      const reviews = pr.reviews();
+      expect(reviews).toHaveLength(2);
+      expect(reviews[0].state()).toBe("CHANGES_REQUESTED");
+      expect(reviews[1].state()).toBe("APPROVED");
+    });
+
+    it("Pull Request Review Comments", () => {
+      const pr = PullRequest.from(issueOrPRByNumber(5));
+      const reviews = pr.reviews();
+      expect(reviews).toHaveLength(2);
+      const comments = reviews[0].comments();
+      expect(comments).toHaveLength(1);
+      const comment = comments[0];
+      expect(comment.url()).toBe(
+        "https://github.com/sourcecred/example-repo/pull/5#discussion_r171460198"
+      );
+      expect(comment.body()).toBe("seems a bit capricious");
+      expect(comment.authors().map((a) => a.login())).toEqual(["wchargin"]);
+    });
+
+    it("Comments", () => {
       const issue = issueOrPRByNumber(6);
       const comments = issue.comments();
       expect(comments.length).toMatchSnapshot();
@@ -61,7 +84,7 @@ describe("GitHub porcelain API", () => {
       expect(comment.authors().map((x) => x.login())).toEqual(["decentralion"]);
     });
 
-  it("Author", () => {
+    it("Authors", () => {
       const authors = repo.authors();
       // So we don't need to manually update the test if a new person posts
       expect(authors.length).toMatchSnapshot();
@@ -76,9 +99,10 @@ describe("GitHub porcelain API", () => {
       expect(decentralion.node()).toMatchSnapshot();
       expect(decentralion.address()).toEqual(decentralion.node().address);
     });
+  });
 
-  describe("type coercion", () => {
+  describe("has type coercion that", () => {
-    it("type coercion works when typed correctly", () => {
+    it("allows refining types when correct", () => {
       const _unused_issue: Issue = Issue.from(issueOrPRByNumber(1));
       const _unused_pr: PullRequest = PullRequest.from(issueOrPRByNumber(3));
       const _unused_author: Author = Author.from(
@@ -88,7 +112,7 @@ describe("GitHub porcelain API", () => {
         issueOrPRByNumber(2).comments()[0]
       );
     });
-    it("type coercion throws error when typed incorrectly", () => {
+    it("throws an error on bad type refinement", () => {
       expect(() => PullRequest.from(issueOrPRByNumber(1))).toThrowError(
         "to have type PULL_REQUEST"
       );