Drop NodeJS 8

.circleci/config.yml

@@ -9,7 +9,7 @@ references:
 jobs:
     build:
         docker:
-            - image: circleci/node:8
+            - image: circleci/node:10
 
         working_directory: ~/repo
 

README.md

@@ -32,7 +32,7 @@ The `tslint-to-eslint-config` command reads in any existing linter, TypeScript,
 For any TSLint rules with corresponding ESLint equivalents, those equivalents will be used in the new configuration.
 TSLint rules without ESLint equivalents will be wrapped with [eslint-plugin-tslint](https://github.com/typescript-eslint/typescript-eslint/tree/master/packages/eslint-plugin-tslint).
 
-> Requires Node 8+ (LTS)
+> Requires Node 10+ (LTS)
 
 ### CLI Flags
 

package.json

@@ -7,31 +7,31 @@
     },
     "description": "Converts your TSLint configuration to the closest reasonable ESLint equivalent.",
     "engines": {
-        "node": ">=8.0.0"
+        "node": ">=10.0.0"
     },
     "dependencies": {
         "chalk": "3.0.0",
-        "commander": "4.0.1",
+        "commander": "4.1.1",
         "strip-json-comments": "^3.0.1",
-        "tslint": "5.20.1",
-        "typescript": "3.7.4"
+        "tslint": "6.0.0",
+        "typescript": "3.7.5"
     },
     "devDependencies": {
-        "@babel/core": "7.7.7",
-        "@babel/plugin-proposal-nullish-coalescing-operator": "^7.7.4",
-        "@babel/plugin-proposal-optional-chaining": "^7.7.5",
-        "@babel/preset-env": "7.7.7",
-        "@babel/preset-typescript": "7.7.7",
-        "@types/jest": "24.0.24",
-        "@types/node": "12.12.21",
-        "@typescript-eslint/eslint-plugin": "2.12.0",
-        "@typescript-eslint/parser": "2.12.0",
-        "babel-jest": "24.9.0",
+        "@babel/core": "7.8.4",
+        "@babel/plugin-proposal-nullish-coalescing-operator": "^7.8.3",
+        "@babel/plugin-proposal-optional-chaining": "^7.8.3",
+        "@babel/preset-env": "7.8.4",
+        "@babel/preset-typescript": "7.8.3",
+        "@types/jest": "25.1.2",
+        "@types/node": "13.7.1",
+        "@typescript-eslint/eslint-plugin": "2.19.2",
+        "@typescript-eslint/parser": "2.19.2",
+        "babel-jest": "25.1.0",
         "eslint": "6.8.0",
-        "eslint-config-prettier": "6.7.0",
-        "husky": "3.1.0",
-        "jest": "24.9.0",
-        "lint-staged": "9.5.0",
+        "eslint-config-prettier": "6.10.0",
+        "husky": "4.2.3",
+        "jest": "25.1.0",
+        "lint-staged": "10.0.7",
         "prettier": "1.19.1",
         "strip-ansi": "6.0.0"
     },

src/adapters/exec.stubs.ts

@@ -3,8 +3,8 @@ export type CreateStubExecSettings = {
     stdout: string;
 };
 
-export const createStubExec = ({ stderr = "", stdout = "" } = {}) =>
+export const createStubExec = ({ stderr = "", stdout = "" } = {}): jest.Mock =>
     jest.fn().mockReturnValue(Promise.resolve({ stderr, stdout }));
 
-export const createStubThrowingExec = ({ stderr = "" } = {}) =>
+export const createStubThrowingExec = ({ stderr = "" } = {}): jest.Mock =>
     jest.fn().mockRejectedValue(Promise.resolve(new Error(stderr)));

src/adapters/fileSystem.stub.ts

@@ -1,10 +1,16 @@
-export const createStubFileSystem = ({ data = {}, exists = true } = {}) => ({
+type FileSystemStub = {
+    fileExists: jest.Mock;
+    readFile: jest.Mock;
+    writeFile: jest.Mock;
+};
+
+export const createStubFileSystem = ({ data = {}, exists = true } = {}): FileSystemStub => ({
     fileExists: jest.fn().mockReturnValue(exists),
     readFile: jest.fn().mockReturnValue(Promise.resolve(data)),
     writeFile: jest.fn(),
 });
 
-export const createStubThrowingFileSystem = ({ err = "" } = {}) => ({
+export const createStubThrowingFileSystem = ({ err = "" } = {}): FileSystemStub => ({
     fileExists: jest.fn().mockRejectedValue(Promise.resolve(new Error(err))),
     readFile: jest.fn().mockRejectedValue(Promise.resolve(new Error(err))),
     writeFile: jest.fn().mockRejectedValue(Promise.resolve(new Error(err))),

src/adapters/logger.stubs.ts

@@ -3,7 +3,28 @@ import stripAnsi from "strip-ansi";
 
 const debugFileName = "stub-output.log";
 
-const createStubWritableStream = () => ({
+type StubWritableStream = {
+    writable: boolean;
+    addListener: jest.Mock;
+    emit: jest.Mock;
+    end: jest.Mock;
+    eventNames: jest.Mock;
+    getMaxListeners: jest.Mock;
+    listenerCount: jest.Mock;
+    listeners: jest.Mock;
+    off: jest.Mock;
+    on: jest.Mock;
+    once: jest.Mock;
+    prependListener: jest.Mock;
+    prependOnceListener: jest.Mock;
+    rawListeners: jest.Mock;
+    removeAllListeners: jest.Mock;
+    removeListener: jest.Mock;
+    setMaxListeners: jest.Mock;
+    write: jest.Mock;
+};
+
+const createStubWritableStream = (): StubWritableStream => ({
     writable: true,
     addListener: jest.fn(),
     emit: jest.fn(),
@@ -24,7 +45,14 @@ const createStubWritableStream = () => ({
     write: jest.fn(),
 });
 
-export const createStubLogger = () => ({
+type StubLogger = {
+    debugFileName: string;
+    info: StubWritableStream;
+    stderr: StubWritableStream;
+    stdout: StubWritableStream;
+};
+
+export const createStubLogger = (): StubLogger => ({
     debugFileName,
     info: createStubWritableStream(),
     stderr: createStubWritableStream(),
@@ -39,7 +67,7 @@ const removeOddCharactersAndTrim = (text: string) =>
         )
         .trim();
 
-export const expectEqualWrites = (fn: jest.Mock, ...actual: string[]) => {
+export const expectEqualWrites = (fn: jest.Mock, ...actual: string[]): void => {
     const realCalls = removeOddCharactersAndTrim(fn.mock.calls.map(args => args.join("")).join(""));
     const actualCalls = removeOddCharactersAndTrim(actual.join(EOL) + EOL);
 

src/adapters/nativeImporter.ts

@@ -1,6 +1,6 @@
 export type NativeImporter = (moduleName: string) => unknown | Error;
 
-export const nativeImporter = async (moduleName: string) => {
+export const nativeImporter = async (moduleName: string): Promise<unknown | Error> => {
     try {
         return await import(moduleName);
     } catch (error) {

src/cli/main.ts

@@ -135,7 +135,7 @@ const runCliDependencies: RunCliDependencies = {
     logger: processLogger,
 };
 
-export const main = async (argv: string[]) => {
+export const main = async (argv: string[]): Promise<void> => {
     try {
         const resultStatus = await runCli(runCliDependencies, argv);
         processLogger.info.close();

src/cli/runCli.ts

@@ -88,5 +88,9 @@ const logErrorResult = (result: ResultWithStatus, dependencies: RunCliDependenci
                 dependencies.logger.stderr.write(chalk.gray(`  ${error.stack}${EOL}`));
             }
             break;
+
+        case ResultStatus.Succeeded:
+            // TODO: Display a nice message?
+            break;
     }
 };

src/creation/eslint/createEnv.ts

@@ -1,9 +1,15 @@
 import { AllOriginalConfigurations } from "../../input/findOriginalConfigurations";
 
+type EnvData = {
+    browser: boolean;
+    es6: boolean;
+    node: boolean;
+};
+
 export const createEnv = ({
     packages,
     typescript,
-}: Pick<AllOriginalConfigurations, "packages" | "typescript">) => {
+}: Pick<AllOriginalConfigurations, "packages" | "typescript">): {} | Partial<EnvData> => {
     const browser =
         typescript === undefined ||
         typescript.compilerOptions.lib === undefined ||

src/creation/formatConvertedRules.ts

@@ -6,11 +6,11 @@ import { formatMissingRules } from "./formatMissingRules";
 export const formatConvertedRules = (
     conversionResults: RuleConversionResults,
     tslintConfiguration: TSLintConfiguration,
-) => {
+): { [r: string]: string | any[] } => {
     const output: { [i: string]: string | any[] } = {};
-    const sortedRuleEntries = Array.from(conversionResults.converted).sort(
-        ([ruleNameA], [ruleNameB]) => ruleNameA.localeCompare(ruleNameB),
-    );
+    const sortedRuleEntries = Array.from(
+        conversionResults.converted,
+    ).sort(([ruleNameA], [ruleNameB]) => ruleNameA.localeCompare(ruleNameB));
 
     for (const [ruleName, rule] of sortedRuleEntries) {
         output[ruleName] = formatConvertedRule(rule);

src/creation/formatMissingRules.ts

@@ -1,5 +1,6 @@
 import { TSLintRuleOptions } from "../rules/types";
 
+// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
 export const formatMissingRules = (missing: TSLintRuleOptions[], rulesDirectory: string[] = []) => {
     const rules: Record<string, unknown> = {};
 

src/creation/formatting/formatters/formatJsOutput.ts

@@ -2,6 +2,7 @@ import { EOL } from "os";
 
 import { withKeysSorted } from "./withKeysSorted";
 
-export const formatJsOutput = (configuration: any) => {
+// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
+export const formatJsOutput = (configuration: any): string => {
     return `module.exports = ${JSON.stringify(withKeysSorted(configuration), undefined, 4)};${EOL}`;
 };

src/creation/formatting/formatters/formatJsonOutput.ts

@@ -2,6 +2,7 @@ import { EOL } from "os";
 
 import { withKeysSorted } from "./withKeysSorted";
 
-export const formatJsonOutput = (configuration: any) => {
+// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
+export const formatJsonOutput = (configuration: any): string => {
     return `${JSON.stringify(withKeysSorted(configuration), undefined, 4)}${EOL}`;
 };

src/creation/formatting/formatters/withKeysSorted.ts

@@ -1,4 +1,5 @@
-export const withKeysSorted = (input: any) => {
+// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
+export const withKeysSorted = (input: any): Record<string, any> => {
     const output: Record<string, any> = {};
     const keys = Object.keys(input).sort((a, b) => a.localeCompare(b));
 

src/creation/simplification/collectTSLintRulesets.ts

@@ -15,7 +15,7 @@ const nativeExtensions = new Map([
 
 export const collectTSLintRulesets = (
     tslint: OriginalConfigurations<Pick<TSLintConfiguration, "extends">>,
-) => {
+): string[] => {
     const allExtensions = uniqueFromSources(tslint.full.extends, tslint.raw.extends);
 
     const extensions = new Set<string>();

src/creation/simplification/resolveExtensionNames.ts

@@ -1,4 +1,4 @@
-export const resolveExtensionNames = (rawExtensionNames: string | string[]) => {
+export const resolveExtensionNames = (rawExtensionNames: string | string[]): string[] => {
     if (typeof rawExtensionNames === "string") {
         rawExtensionNames = [rawExtensionNames];
     }

src/creation/writeConversionResults.ts

@@ -15,7 +15,7 @@ export const writeConversionResults = async (
     outputPath: string,
     ruleConversionResults: RuleConversionResults & SimplifiedRuleConversionResults,
     originalConfigurations: AllOriginalConfigurations,
-) => {
+): Promise<undefined | Error> => {
     const plugins = ["@typescript-eslint"];
     const { eslint, tslint } = originalConfigurations;
 

src/creation/writeEditorConfigConversionResults.ts

@@ -13,7 +13,7 @@ export const writeConversionResults = async (
     outputPath: string,
     conversionResults: EditorSettingConversionResults,
     originalConfiguration: DeepPartial<EditorConfiguration>,
-) => {
+): Promise<undefined | Error> => {
     const output = {
         ...originalConfiguration,
         ...formatConvertedSettings(conversionResults),
@@ -22,7 +22,11 @@ export const writeConversionResults = async (
     return await dependencies.fileSystem.writeFile(outputPath, formatOutput(outputPath, output));
 };
 
-export const formatConvertedSettings = (conversionResults: EditorSettingConversionResults) => {
+export const formatConvertedSettings = (
+    conversionResults: EditorSettingConversionResults,
+): {
+    [i: string]: string | any[];
+} => {
     const output: { [i: string]: string | any[] } = {};
     const sortedEntries = Array.from(conversionResults.converted).sort(([nameA], [nameB]) =>
         nameA.localeCompare(nameB),

src/editorSettings/convertEditorSetting.ts

@@ -1,11 +1,13 @@
 import { ConversionError } from "../errors/conversionError";
-import { EditorSettingConverter } from "./converter";
+import { EditorSettingConverter, EditorSettingConversionResult } from "./converter";
 import { EditorSetting } from "./types";
 
+type ConvertEditorSetting = ConversionError | EditorSettingConversionResult | undefined;
+
 export const convertEditorSetting = (
     editorSetting: EditorSetting,
     converters: Map<string, EditorSettingConverter>,
-) => {
+): ConvertEditorSetting => {
     const converter = converters.get(editorSetting.editorSettingName);
     if (converter === undefined) {
         return undefined;

src/errors/conversionError.ts

@@ -7,7 +7,7 @@ import { ErrorSummary } from "./errorSummary";
 export class ConversionError implements ErrorSummary {
     private constructor(private readonly summary: string) {}
 
-    public static forMerger(eslintRule: string) {
+    public static forMerger(eslintRule: string): ConversionError {
         return new ConversionError(
             [
                 `Error: multiple output ${eslintRule} ESLint rule options were generated, but tslint-to-eslint-config doesn't have "merger" logic to deal with this.`,
@@ -16,13 +16,13 @@ export class ConversionError implements ErrorSummary {
         );
     }
 
-    public static forRuleError(error: Error, tslintRule: TSLintRuleOptions) {
+    public static forRuleError(error: Error, tslintRule: TSLintRuleOptions): ConversionError {
         return new ConversionError(
             `${tslintRule.ruleName} threw an error during conversion: ${error.stack}${EOL}`,
         );
     }
 
-    public static forSettingError(error: Error, editorSetting: EditorSetting) {
+    public static forSettingError(error: Error, editorSetting: EditorSetting): ConversionError {
         return new ConversionError(
             `${editorSetting.editorSettingName} threw an error during conversion: ${error.stack}${EOL}`,
         );

src/input/findEditorConfiguration.test.ts

@@ -7,7 +7,7 @@ import { DEFAULT_VSCODE_SETTINGS_PATH } from "./vsCodeSettings";
 
 const stubConfigPath = "temp/";
 
-export const createStubImporter = (filePath = "") =>
+export const createStubImporter = (filePath = ""): jest.Mock =>
     jest.fn().mockReturnValue(Promise.resolve(filePath));
 
 const createStubDependencies = (overrides: Partial<FindEditorConfigurationDependencies> = {}) => ({

src/input/findEditorConfiguration.ts

@@ -11,6 +11,7 @@ export type FindEditorConfigurationDependencies = {
     importer: SansDependencies<typeof importer>;
 };
 
+// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
 export const findEditorConfiguration = async (
     dependencies: FindEditorConfigurationDependencies,
     specifiedConfigPath: string | undefined,

src/input/findTSLintConfiguration.ts

@@ -18,6 +18,7 @@ export type FindTSLintConfigurationDependencies = {
     importer: SansDependencies<typeof importer>;
 };
 
+// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
 export const findTSLintConfiguration = async (
     dependencies: FindTSLintConfigurationDependencies,
     config: string | undefined,

src/reporting/reportConversionResults.ts

@@ -15,7 +15,7 @@ import {
 export const reportConversionResults = (
     dependencies: ReportConversionResultsDependencies,
     ruleConversionResults: RuleConversionResults,
-) => {
+): void => {
     if (ruleConversionResults.converted.size !== 0) {
         logSuccessfulConversions("rule", ruleConversionResults.converted, dependencies.logger);
         logNotices(ruleConversionResults.converted, dependencies.logger);

src/reporting/reportEditorSettingConversionResults.ts

@@ -12,7 +12,7 @@ import {
 export const reportEditorSettingConversionResults = (
     dependencies: ReportConversionResultsDependencies,
     editorSettingConversionResults: EditorSettingConversionResults,
-) => {
+): void => {
     if (editorSettingConversionResults.converted.size !== 0) {
         logSuccessfulConversions(
             "editor setting",