feat: retrieve issue co-authors (#445)

## PR Checklist

- [x] Addresses an existing open issue: fixes #252
- [x] That issue was marked as [`status: accepting
prs`](https://github.com/JoshuaKGoldberg/all-contributors-for-repository/issues?q=is%3Aopen+is%3Aissue+label%3A%22status%3A+accepting+prs%22)
- [x] Steps in
[CONTRIBUTING.md](https://github.com/JoshuaKGoldberg/all-contributors-for-repository/blob/main/.github/CONTRIBUTING.md)
were taken

## Overview

Adds in the same co-author detection using `description-to-co-authors`
for issue bodies as commit bodies.

💖

package.json

@@ -38,8 +38,8 @@
 	},
 	"dependencies": {
 		"co-author-to-username": "^0.1.1",
-		"commit-to-co-authors": "^0.1.0",
 		"conventional-commits-parser": "^6.0.0",
+		"description-to-co-authors": "^0.3.0",
 		"octokit": "^4.0.0"
 	},
 	"devDependencies": {

src/collect/adding/addAcceptedIssues.test.ts

@@ -11,18 +11,32 @@ const options = {
 };
 
 const login = "abc123";
+const loginCoAuthor = "other-login";
 
-const createStubIssue = (label: string) =>
+const mockDescriptionToCoAuthors = vi
+	.fn()
+	.mockReturnValue([{ username: loginCoAuthor }]);
+
+vi.mock("description-to-co-authors", () => ({
+	get descriptionToCoAuthors() {
+		return mockDescriptionToCoAuthors;
+	},
+}));
+
+const createStubIssue = ({ body, labels }: Partial<AcceptedIssue>) =>
 	({
-		labels: [label],
+		body,
+		labels,
 		number: 0,
 		user: { login },
 	}) as AcceptedIssue;
 
 describe("addAcceptedIssues", () => {
 	it("adds an issue when it has a bug label", () => {
 		const add = vi.fn();
-		const issue = createStubIssue(options.labelTypeBug);
+		const issue = createStubIssue({
+			labels: [options.labelTypeBug],
+		});
 
 		addAcceptedIssues([issue], { add }, options);
 
@@ -31,7 +45,9 @@ describe("addAcceptedIssues", () => {
 
 	it("adds an issue when it has a docs label", () => {
 		const add = vi.fn();
-		const issue = createStubIssue(options.labelTypeDocs);
+		const issue = createStubIssue({
+			labels: [options.labelTypeDocs],
+		});
 
 		addAcceptedIssues([issue], { add }, options);
 
@@ -40,7 +56,9 @@ describe("addAcceptedIssues", () => {
 
 	it("adds an issue when it has a feature label", () => {
 		const add = vi.fn();
-		const issue = createStubIssue(options.labelTypeIdeas);
+		const issue = createStubIssue({
+			labels: [options.labelTypeIdeas],
+		});
 
 		addAcceptedIssues([issue], { add }, options);
 
@@ -49,16 +67,46 @@ describe("addAcceptedIssues", () => {
 
 	it("adds an issue when it has a tool label", () => {
 		const add = vi.fn();
-		const issue = createStubIssue(options.labelTypeTool);
+		const issue = createStubIssue({
+			labels: [options.labelTypeTool],
+		});
+
+		addAcceptedIssues([issue], { add }, options);
+
+		expect(add).toHaveBeenCalledWith(login, issue.number, "tool");
+	});
+
+	it("adds an issue's co-author when the body includes them", () => {
+		const add = vi.fn();
+		const issue = createStubIssue({
+			body: `(mocked)`,
+			labels: [options.labelTypeTool],
+		});
+
+		addAcceptedIssues([issue], { add }, options);
+
+		expect(add).toHaveBeenCalledWith(login, issue.number, "tool");
+		expect(add).toHaveBeenCalledWith(loginCoAuthor, issue.number, "tool");
+		expect(mockDescriptionToCoAuthors).toHaveBeenCalledWith(issue.body);
+	});
+
+	it("doesn't call for co-authors when there is no issue body", () => {
+		const add = vi.fn();
+		const issue = createStubIssue({
+			labels: [options.labelTypeTool],
+		});
 
 		addAcceptedIssues([issue], { add }, options);
 
 		expect(add).toHaveBeenCalledWith(login, issue.number, "tool");
+		expect(add).toHaveBeenCalledTimes(1);
 	});
 
 	it("doesn't add an issue when it has an unrelated label", () => {
 		const add = vi.fn();
-		const issue = createStubIssue("other");
+		const issue = createStubIssue({
+			labels: ["other"],
+		});
 
 		addAcceptedIssues([issue], { add }, options);
 

src/collect/adding/addAcceptedIssues.ts

@@ -1,3 +1,4 @@
+import { descriptionToCoAuthors } from "description-to-co-authors";
 import { ContributorsCollection } from "../../ContributorsCollection.js";
 import { AllContributorsForRepositoryOptions } from "../../options.js";
 import { AcceptedIssue } from "../collecting/collectAcceptedIssues.js";
@@ -25,12 +26,24 @@ export function addAcceptedIssues(
 			// - 🔧 `tool`: authors of merged PRs that address issues labeled as tooling
 			[options.labelTypeTool, "tool"],
 		] as const) {
-			if (labels.some((label) => label === labelType)) {
-				contributors.add(
-					acceptedIssue.user?.login,
-					acceptedIssue.number,
-					contribution,
-				);
+			if (!labels.some((label) => label === labelType)) {
+				continue;
+			}
+
+			const logins = [];
+
+			if (acceptedIssue.user) {
+				logins.push(acceptedIssue.user.login);
+			}
+
+			if (acceptedIssue.body) {
+				for (const coAuthor of descriptionToCoAuthors(acceptedIssue.body)) {
+					logins.push(coAuthor.username);
+				}
+			}
+
+			for (const login of logins) {
+				contributors.add(login, acceptedIssue.number, contribution);
 			}
 		}
 	}

src/collect/parsing/parseMergedPullAuthors.ts

@@ -1,5 +1,5 @@
 import { CachingCoAuthorToUsername } from "co-author-to-username";
-import { commitToCoAuthors } from "commit-to-co-authors";
+import { descriptionToCoAuthors } from "description-to-co-authors";
 
 interface MergedPullForAuthors {
 	body?: string;
@@ -15,7 +15,7 @@ export async function parseMergedPullAuthors(
 	authors.push(mergedPull.user?.login);
 
 	if (mergedPull.body) {
-		const coAuthors = commitToCoAuthors(mergedPull.body);
+		const coAuthors = descriptionToCoAuthors(mergedPull.body);
 
 		for (const coAuthor of coAuthors) {
 			authors.push(await cachingCoAuthorToUsername(coAuthor));