Convert from JavaScript to TypeScript

.eslintrc.json

@@ -0,0 +1,26 @@
+{
+  "parser": "@typescript-eslint/parser",
+  "env": {
+    "node": true,
+    "jest": true
+  },
+  "extends": [
+    "eslint:recommended",
+    "plugin:@typescript-eslint/recommended",
+    "plugin:@typescript-eslint/strict"
+  ],
+  "parserOptions": {
+    "project": "./tsconfig.json",
+    "ecmaVersion": 2015
+  },
+  "rules": {
+    "@typescript-eslint/no-explicit-any": "error",
+    "@typescript-eslint/explicit-module-boundary-types": "error",
+    "@typescript-eslint/strict-boolean-expressions": "error",
+    "@typescript-eslint/no-unused-vars": ["error", { "argsIgnorePattern": "^_" }],
+    "@typescript-eslint/explicit-function-return-type": "error",
+    "no-nested-ternary": "error",
+    "no-use-before-define": "off",
+    "no-restricted-syntax": "off"
+  }
+}

jest.config.json

@@ -0,0 +1,11 @@
+{
+    "preset": "ts-jest",
+    "testEnvironment": "node",
+    "transform": {
+        "^.+\\.ts$": "ts-jest"
+    },
+    "transformIgnorePatterns": [
+        "/node_modules/"
+    ],
+    "moduleFileExtensions": ["ts", "js", "json", "node"]
+}

lib/comment.ts

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+import * as Mustache from 'mustache';
+import {MinimatchOptions} from 'minimatch/dist/esm';
+import { Snippet } from './snippets';
+import { TemplateVariables } from "./config";
+
+export type Comment = {
+  id: number;
+  url: string;
+  created_at: string;
+  body?: string;
+  body_text?: string;
+  body_html?: string;
+}
+
+export interface CommentObject extends Map<string, unknown>{
+  get(key: 'header' | 'footer' | 'onCreate' | 'onUpdate'): string;
+  get(key: 'snippets'): Snippet[],
+  get(key: 'on-create' | 'on-update' | 'globOptions'): Map<string, unknown>[];
+  get(key: 'globOptions'): MinimatchOptions | undefined;
+}
+
+function commentMetadata(snippetIds: string[]): string {
+  return `<!-- pr-commenter-metadata: ${snippetIds.join(',')} -->`;
+}
+
+function extractCommentMetadata(commentBody: string): string[] | null {
+  // snippet id regex plus a comma
+  const regex = /<!-- pr-commenter-metadata: ([A-Za-z0-9\-_,]*) -->/;
+  const match = regex.exec(commentBody);
+
+  if (match) {
+    return match[1].split(',').map((s: string) => s.trim()).filter((s) => s !== '');
+  }
+  return null;
+}
+
+function assembleCommentBody(
+    snippetIds: string[],
+    commentConfig: CommentObject,
+    templateVariables:  TemplateVariables = {}): string {
+  let strings = [
+    commentConfig.get('header'),
+    ...(commentConfig.get('snippets')).map(snippet => {
+      if (snippetIds.includes(snippet.get('id'))) {
+        return snippet.get('body');
+      }
+      return null;
+    }),
+    commentConfig.get('footer'),
+    commentMetadata(snippetIds),
+  ];
+
+  strings = strings.filter((s) => Boolean(s));
+
+  const rawCommentBody = strings.join('\n\n');
+
+  return Mustache.render(rawCommentBody, templateVariables);
+}
+
+function newCommentDifferentThanPreviousComment(previousComment: Comment, snippetIds: string[]): boolean {
+  const previousSnippetIds = (previousComment.body != null) ? extractCommentMetadata(previousComment.body) : null;
+
+  return previousSnippetIds !== null && previousSnippetIds.join(',') !== snippetIds.join(',');
+}
+
+function newCommentWouldHaveContent(snippetIds: string[]): boolean {
+  return snippetIds.length > 0;
+}
+
+function shouldPostNewComment(
+    previousComment: Comment | null,
+    snippetIds: string[],
+    commentConfig: CommentObject
+): boolean {
+  const isNotEmpty = newCommentWouldHaveContent(snippetIds);
+  const isCreating = !previousComment && commentConfig.get('onCreate') === 'create';
+  const isUpdating = !!previousComment
+    && commentConfig.get('onUpdate') === 'recreate'
+    && newCommentDifferentThanPreviousComment(previousComment, snippetIds);
+
+  return isNotEmpty && (isCreating || isUpdating);
+}
+
+function shouldDeletePreviousComment(
+    previousComment: Comment | null,
+    snippetIds: string[],
+    commentConfig: CommentObject
+): boolean {
+  return !!previousComment && (
+    shouldPostNewComment(previousComment, snippetIds, commentConfig)
+    || (!newCommentWouldHaveContent(snippetIds) && commentConfig.get('onUpdate') !== 'nothing')
+  );
+}
+
+function shouldEditPreviousComment(
+    previousComment: Comment | null,
+    snippetIds: string[],
+    commentConfig: CommentObject
+): boolean {
+  return newCommentWouldHaveContent(snippetIds) && (
+    !!previousComment
+      && commentConfig.get('onUpdate') === 'edit'
+      && newCommentDifferentThanPreviousComment(previousComment, snippetIds)
+  );
+}
+
+export {
+  commentMetadata,
+  assembleCommentBody,
+  extractCommentMetadata,
+  shouldPostNewComment,
+  shouldDeletePreviousComment,
+  shouldEditPreviousComment,
+};