feat(tests): Add initial unit tests and GH Actions to ensure they pass

.github/workflows/pr-check.yml

@@ -8,6 +8,11 @@ on:
 jobs:
   build-and-lint:
     runs-on: ubuntu-latest
+    outputs:
+      eslint_status: ${{ steps.eslint.outcome }}
+      prettier_status: ${{ steps.prettier.outcome }}
+      tests_status: ${{ steps.tests.outcome }}
+      build_status: ${{ steps.build.outcome }}
 
     steps:
     - name: Check out repository code
@@ -22,13 +27,35 @@ jobs:
       run: npm ci
 
     - name: Run ESLint
+      id: eslint
+      continue-on-error: true
       run: npm run lint
 
     - name: Run Prettier check
+      id: prettier
+      continue-on-error: true
       run: npm run prettier-check
 
+    - name: Run Tests
+      id: tests
+      continue-on-error: true
+      run: npm run tests
+
     - name: Run npm build
+      id: build
+      continue-on-error: true
       run: npm run build
 
-    - name: Report errors
-      run: echo "Build and lint checks completed successfully."
+    - name: Report Errors
+      if: ${{ always() }}
+      run: |
+        echo "ESLint status: ${{ steps.eslint.outcome }}"
+        echo "Prettier status: ${{ steps.prettier.outcome }}"
+        echo "Tests status: ${{ steps.tests.outcome }}"
+        echo "Build status: ${{ steps.build.outcome }}"
+        if [[ ${{ steps.eslint.outcome }} == 'failure' ]] \
+        || [[ ${{ steps.prettier.outcome }} == 'failure' ]] \
+        || [[ ${{ steps.tests.outcome }} == 'failure' ]] \
+        || [[ ${{ steps.build.outcome }} == 'failure' ]]; then
+          exit 1
+        fi

esbuild.config.mjs

@@ -60,7 +60,7 @@ const mermaid_renderer_plugin = {
 
 const prod = (process.argv[2] === 'production');
 
-esbuild.build({
+const context = await esbuild.context({
 	banner: {
 		js: banner,
 	},
@@ -83,7 +83,6 @@ esbuild.build({
 		...builtins
 	],
 	format: 'cjs',
-	watch: !prod,
 	target: 'chrome106',
 	logLevel: "info",
 	sourcemap: prod ? false : 'inline',
@@ -92,4 +91,11 @@ esbuild.build({
 	mainFields: ['module', 'main'],
 	plugins: [mermaid_renderer_plugin],
 	minify: true,
-}).catch(() => process.exit(1));
+});
+
+
+if (prod) {
+	context.build().catch(() => process.exit(1));
+} else {
+	context.watch().catch(() => process.exit(1));
+}

jest.config.ts

@@ -0,0 +1,204 @@
+/* eslint-disable @typescript-eslint/naming-convention */
+/*
+ * For a detailed explanation regarding each configuration property and type check, visit:
+ * https://jestjs.io/docs/configuration
+ */
+
+export default {
+  // All imported modules in your tests should be mocked automatically
+  // automock: false,
+
+  // Stop running tests after `n` failures
+  // bail: 0,
+
+  // The directory where Jest should store its cached dependency information
+  // cacheDirectory: "/private/var/folders/qx/1pyrtldd3nb1l0p44xbmd97h0000gn/T/jest_dx",
+
+  // Automatically clear mock calls, instances, contexts and results before every test
+  // clearMocks: false,
+
+  // Indicates whether the coverage information should be collected while executing the test
+  // collectCoverage: false,
+
+  // An array of glob patterns indicating a set of files for which coverage information should be collected
+  // collectCoverageFrom: undefined,
+
+  // The directory where Jest should output its coverage files
+  // coverageDirectory: undefined,
+
+  // An array of regexp pattern strings used to skip coverage collection
+  // coveragePathIgnorePatterns: [
+  //   "/node_modules/"
+  // ],
+
+  // Indicates which provider should be used to instrument code for coverage
+  coverageProvider: "v8",
+
+  // A list of reporter names that Jest uses when writing coverage reports
+  // coverageReporters: [
+  //   "json",
+  //   "text",
+  //   "lcov",
+  //   "clover"
+  // ],
+
+  // An object that configures minimum threshold enforcement for coverage results
+  // coverageThreshold: undefined,
+
+  // A path to a custom dependency extractor
+  // dependencyExtractor: undefined,
+
+  // Make calling deprecated APIs throw helpful error messages
+  // errorOnDeprecated: false,
+
+  // The default configuration for fake timers
+  // fakeTimers: {
+  //   "enableGlobally": false
+  // },
+
+  // Force coverage collection from ignored files using an array of glob patterns
+  // forceCoverageMatch: [],
+
+  // A path to a module which exports an async function that is triggered once before all test suites
+  // globalSetup: undefined,
+
+  // A path to a module which exports an async function that is triggered once after all test suites
+  // globalTeardown: undefined,
+
+  // A set of global variables that need to be available in all test environments
+  // globals: {},
+
+  // The maximum amount of workers used to run your tests. Can be specified as % or a number. E.g. maxWorkers: 10% will use 10% of your CPU amount + 1 as the maximum worker number. maxWorkers: 2 will use a maximum of 2 workers.
+  // maxWorkers: "50%",
+
+  // An array of directory names to be searched recursively up from the requiring module's location
+  // moduleDirectories: [
+  //   "node_modules"
+  // ],
+
+  // An array of file extensions your modules use
+  // moduleFileExtensions: [
+  //   "js",
+  //   "mjs",
+  //   "cjs",
+  //   "jsx",
+  //   "ts",
+  //   "tsx",
+  //   "json",
+  //   "node"
+  // ],
+
+  // A map from regular expressions to module names or to arrays of module names that allow to stub out resources with a single module
+  // moduleNameMapper: {},
+
+  // An array of regexp pattern strings, matched against all module paths before considered 'visible' to the module loader
+  // modulePathIgnorePatterns: [],
+
+  // Activates notifications for test results
+  // notify: false,
+
+  // An enum that specifies notification mode. Requires { notify: true }
+  // notifyMode: "failure-change",
+
+  // A preset that is used as a base for Jest's configuration
+  // preset: undefined,
+  preset: 'ts-jest/presets/js-with-ts',
+
+  // Run tests from one or more projects
+  // projects: undefined,
+
+  // Use this configuration option to add custom reporters to Jest
+  reporters: [
+    'default',
+    'github-actions',
+  ],
+
+  // Automatically reset mock state before every test
+  // resetMocks: false,
+
+  // Reset the module registry before running each individual test
+  // resetModules: false,
+
+  // A path to a custom resolver
+  // resolver: undefined,
+
+  // Automatically restore mock state and implementation before every test
+  // restoreMocks: false,
+
+  // The root directory that Jest should scan for tests and modules within
+  // rootDir: undefined,
+
+  // A list of paths to directories that Jest should use to search for files in
+  // roots: [
+  //   "<rootDir>"
+  // ],
+
+  // Allows you to use a custom runner instead of Jest's default test runner
+  // runner: "jest-runner",
+
+  // The paths to modules that run some code to configure or set up the testing environment before each test
+  // setupFiles: [],
+
+  // A list of paths to modules that run some code to configure or set up the testing framework before each test
+  // setupFilesAfterEnv: [],
+
+  // The number of seconds after which a test is considered as slow and reported as such in the results.
+  // slowTestThreshold: 5,
+
+  // A list of paths to snapshot serializer modules Jest should use for snapshot testing
+  // snapshotSerializers: [],
+
+  // The test environment that will be used for testing
+  // testEnvironment: "jest-environment-node",
+
+  // Options that will be passed to the testEnvironment
+  // testEnvironmentOptions: {},
+
+  // Adds a location field to test results
+  // testLocationInResults: false,
+
+  // The glob patterns Jest uses to detect test files
+  // testMatch: [
+  //   "**/__tests__/**/*.[jt]s?(x)",
+  //   "**/?(*.)+(spec|test).[tj]s?(x)"
+  // ],
+
+  // An array of regexp pattern strings that are matched against all test paths, matched tests are skipped
+  // testPathIgnorePatterns: [
+  //   "/node_modules/"
+  // ],
+
+  // The regexp pattern or array of patterns that Jest uses to detect test files
+  // testRegex: [],
+
+  // This option allows the use of a custom results processor
+  // testResultsProcessor: undefined,
+
+  // This option allows use of a custom test runner
+  // testRunner: "jest-circus/runner",
+
+  // A map from regular expressions to paths to transformers
+  // transform: undefined,
+
+  // An array of regexp pattern strings that are matched against all source file paths, matched files will skip transformation
+  // transformIgnorePatterns: [
+  //   "/node_modules/",
+  //   "\\.pnp\\.[^\\/]+$"
+  // ],
+
+  // An array of regexp pattern strings that are matched against all modules before the module loader will automatically return a mock for them
+  // unmockedModulePathPatterns: undefined,
+
+  // Indicates whether each individual test should be reported during the run
+  // verbose: undefined,
+
+  // An array of regexp patterns that are matched against all source file paths before re-running tests in watch mode
+  // watchPathIgnorePatterns: [],
+
+  // Whether to use watchman for file crawling
+  // watchman: true,
+
+
+  transformIgnorePatterns: ["node_modules/(?!(.*))"]
+
+};