feat(assignees): add 6 new options to avoid stale for assignees (#327)

* feat(assignees): add new option to avoid stale for assignees

closes #271

* test: add more coverage

* docs: fix readme format issue

* docs: reorder and enhance typo

* docs(contributing): add more information about the npm scripts

src/classes/assignees.ts

@@ -0,0 +1,251 @@
+import deburr from 'lodash.deburr';
+import {wordsToList} from '../functions/words-to-list';
+import {IAssignee} from '../interfaces/assignee';
+import {IIssuesProcessorOptions} from '../interfaces/issues-processor-options';
+import {Issue} from './issue';
+import {IssueLogger} from './loggers/issue-logger';
+
+type CleanAssignee = string;
+
+export class Assignees {
+  private static _cleanAssignee(assignee: Readonly<string>): CleanAssignee {
+    return deburr(assignee.toLowerCase());
+  }
+
+  private readonly _options: IIssuesProcessorOptions;
+  private readonly _issue: Issue;
+  private readonly _issueLogger: IssueLogger;
+
+  constructor(options: Readonly<IIssuesProcessorOptions>, issue: Issue) {
+    this._options = options;
+    this._issue = issue;
+    this._issueLogger = new IssueLogger(issue);
+  }
+
+  shouldExemptAssignees(): boolean {
+    if (!this._issue.hasAssignees) {
+      this._issueLogger.info('This $$type has no assignee');
+      this._logSkip();
+
+      return false;
+    }
+
+    if (this._shouldExemptAllAssignees()) {
+      this._issueLogger.info(
+        'Skipping $$type because it has an exempt assignee'
+      );
+
+      return true;
+    }
+
+    const exemptAssignees: string[] = this._getExemptAssignees();
+
+    if (exemptAssignees.length === 0) {
+      this._issueLogger.info(
+        `No option was specified to skip the stale process for this $$type`
+      );
+      this._logSkip();
+
+      return false;
+    }
+
+    this._issueLogger.info(
+      `Found ${exemptAssignees.length} assignee${
+        exemptAssignees.length > 1 ? 's' : ''
+      } on this $$type`
+    );
+
+    const hasExemptAssignee: boolean = exemptAssignees.some(
+      (exemptAssignee: Readonly<string>): boolean =>
+        this._hasAssignee(exemptAssignee)
+    );
+
+    if (!hasExemptAssignee) {
+      this._issueLogger.info(
+        'No assignee on this $$type can exempt the stale process'
+      );
+      this._logSkip();
+    } else {
+      this._issueLogger.info(
+        'Skipping this $$type because it has an exempt assignee'
+      );
+    }
+
+    return hasExemptAssignee;
+  }
+
+  private _getExemptAssignees(): string[] {
+    return this._issue.isPullRequest
+      ? this._getExemptPullRequestAssignees()
+      : this._getExemptIssueAssignees();
+  }
+
+  private _getExemptIssueAssignees(): string[] {
+    if (this._options.exemptIssueAssignees === '') {
+      this._issueLogger.info(
+        'The option "exemptIssueAssignees" is disabled. No specific assignee can skip the stale process for this $$type'
+      );
+
+      if (this._options.exemptAssignees === '') {
+        this._issueLogger.info(
+          'The option "exemptAssignees" is disabled. No specific assignee can skip the stale process for this $$type'
+        );
+
+        return [];
+      }
+
+      const exemptAssignees: string[] = wordsToList(
+        this._options.exemptAssignees
+      );
+
+      this._issueLogger.info(
+        `The option "exemptAssignees" is set. ${
+          exemptAssignees.length
+        } assignee${
+          exemptAssignees.length === 1 ? '' : 's'
+        } can skip the stale process for this $$type`
+      );
+
+      return exemptAssignees;
+    }
+
+    const exemptAssignees: string[] = wordsToList(
+      this._options.exemptIssueAssignees
+    );
+
+    this._issueLogger.info(
+      `The option "exemptIssueAssignees" is set. ${
+        exemptAssignees.length
+      } assignee${
+        exemptAssignees.length === 1 ? '' : 's'
+      } can skip the stale process for this $$type`
+    );
+
+    return exemptAssignees;
+  }
+
+  private _getExemptPullRequestAssignees(): string[] {
+    if (this._options.exemptPrAssignees === '') {
+      this._issueLogger.info(
+        'The option "exemptPrAssignees" is disabled. No specific assignee can skip the stale process for this $$type'
+      );
+
+      if (this._options.exemptAssignees === '') {
+        this._issueLogger.info(
+          'The option "exemptAssignees" is disabled. No specific assignee can skip the stale process for this $$type'
+        );
+
+        return [];
+      }
+
+      const exemptAssignees: string[] = wordsToList(
+        this._options.exemptAssignees
+      );
+
+      this._issueLogger.info(
+        `The option "exemptAssignees" is set. ${
+          exemptAssignees.length
+        } assignee${
+          exemptAssignees.length === 1 ? '' : 's'
+        } can skip the stale process for this $$type`
+      );
+
+      return exemptAssignees;
+    }
+
+    const exemptAssignees: string[] = wordsToList(
+      this._options.exemptPrAssignees
+    );
+
+    this._issueLogger.info(
+      `The option "exemptPrAssignees" is set. ${
+        exemptAssignees.length
+      } assignee${
+        exemptAssignees.length === 1 ? '' : 's'
+      } can skip the stale process for this $$type`
+    );
+
+    return exemptAssignees;
+  }
+
+  private _hasAssignee(assignee: Readonly<string>): boolean {
+    const cleanAssignee: CleanAssignee = Assignees._cleanAssignee(assignee);
+
+    return this._issue.assignees.some(
+      (issueAssignee: Readonly<IAssignee>): boolean => {
+        const isSameAssignee: boolean =
+          cleanAssignee === Assignees._cleanAssignee(issueAssignee.login);
+
+        if (isSameAssignee) {
+          this._issueLogger.info(
+            `@${issueAssignee.login} is assigned on this $$type and is an exempt assignee`
+          );
+        }
+
+        return isSameAssignee;
+      }
+    );
+  }
+
+  private _shouldExemptAllAssignees(): boolean {
+    return this._issue.isPullRequest
+      ? this._shouldExemptAllPullRequestAssignees()
+      : this._shouldExemptAllIssueAssignees();
+  }
+
+  private _shouldExemptAllIssueAssignees(): boolean {
+    if (this._options.exemptAllIssueAssignees === true) {
+      this._issueLogger.info(
+        'The option "exemptAllIssueAssignees" is enabled. Any assignee on this $$type will skip the stale process'
+      );
+
+      return true;
+    } else if (this._options.exemptAllIssueAssignees === false) {
+      this._issueLogger.info(
+        'The option "exemptAllIssueAssignees" is disabled. Only some specific assignees on this $$type will skip the stale process'
+      );
+
+      return false;
+    }
+
+    this._logExemptAllAssigneesOption();
+
+    return this._options.exemptAllAssignees;
+  }
+
+  private _shouldExemptAllPullRequestAssignees(): boolean {
+    if (this._options.exemptAllPrAssignees === true) {
+      this._issueLogger.info(
+        'The option "exemptAllPrAssignees" is enabled. Any assignee on this $$type will skip the stale process'
+      );
+
+      return true;
+    } else if (this._options.exemptAllPrAssignees === false) {
+      this._issueLogger.info(
+        'The option "exemptAllPrAssignees" is disabled. Only some specific assignees on this $$type will skip the stale process'
+      );
+
+      return false;
+    }
+
+    this._logExemptAllAssigneesOption();
+
+    return this._options.exemptAllAssignees;
+  }
+
+  private _logExemptAllAssigneesOption(): void {
+    if (this._options.exemptAllAssignees) {
+      this._issueLogger.info(
+        'The option "exemptAllAssignees" is enabled. Any assignee on this $$type will skip the stale process'
+      );
+    } else {
+      this._issueLogger.info(
+        'The option "exemptAllAssignees" is disabled. Only some specific assignees on this $$type will skip the stale process'
+      );
+    }
+  }
+
+  private _logSkip(): void {
+    this._issueLogger.info('Skip the assignees checks');
+  }
+}