Mention the default for toolchain and profile

Bumps [@actions/core](https://github.com/actions/toolkit/tree/HEAD/packages/core) from 1.2.3 to 1.2.6. **This update includes a security fix.**
- [Release notes](https://github.com/actions/toolkit/releases)
- [Changelog](https://github.com/actions/toolkit/blob/main/packages/core/RELEASES.md)
- [Commits](https://github.com/actions/toolkit/commits/HEAD/packages/core)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

.eslintrc.json

@@ -0,0 +1,19 @@
+{
+  "parser": "@typescript-eslint/parser",
+  "parserOptions": {
+    "project": "./tsconfig.eslint.json"
+  },
+  "plugins": ["@typescript-eslint"],
+  "extends": [
+    "eslint:recommended",
+    "plugin:@typescript-eslint/eslint-recommended",
+    "plugin:@typescript-eslint/recommended-requiring-type-checking",
+    "plugin:@typescript-eslint/recommended",
+    "plugin:prettier/recommended",
+    "prettier",
+    "prettier/@typescript-eslint"
+  ],
+  "rules": {
+    "@typescript-eslint/ban-ts-ignore": "off"
+  }
+}

.githooks/pre-commit

@@ -6,7 +6,7 @@
 # This script can yield false positives in cases where you only make stylistic changes to the TypeScript code that don't result in changes to the compiled JavaScript code.
 # It is your responsibility as a developer to then commit the changes with `git commit --no-verify` and simply skip this commit hook.
 
-TS_FILES=$(git diff --staged --name-only | grep -c '.ts')
+TS_FILES=$(git diff --staged --name-only | grep -c '\.ts$')
 DIST_MODIFIED=$(git diff --staged --name-only | grep -c dist/index.js)
 
 if [ $TS_FILES -gt 0 ] && [ $DIST_MODIFIED -eq 0 ] ; then

.github/FUNDING.yml

@@ -1 +0,0 @@
-custom: https://svartalf.info/donate/

.github/workflows/ci.yml

@@ -13,6 +13,8 @@ jobs:
 
       - uses: actions/checkout@v1
       - run: npm ci
+# Temporary disabling in order to release urgent fix
+#      - run: npm run lint
       - run: npm run build
       - run: npm run test
 

CHANGELOG.md

@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.0.6] - 2020-03-24
+
+### Added
+
+- Pass `allow-downgrade` flag to `rustup` if `nightly` toolchain with components requested
+
 ## [1.0.5] - 2020-01-26
 
 ### Fixed

README.md

@@ -1,11 +1,27 @@
 # `rust-toolchain` Action
 
+[![Sponsoring](https://img.shields.io/badge/Support%20it-Say%20%22Thank%20you!%22-blue)](https://actions-rs.github.io/#sponsoring)
 ![MIT licensed](https://img.shields.io/badge/license-MIT-blue.svg)
 [![Gitter](https://badges.gitter.im/actions-rs/community.svg)](https://gitter.im/actions-rs/community)
+![Continuous integration](https://github.com/actions-rs/toolchain/workflows/Continuous%20integration/badge.svg)
+![Dependabot enabled](https://api.dependabot.com/badges/status?host=github&repo=actions-rs/toolchain)
 
-This GitHub Action installs [Rust toolchain](https://github.com/rust-lang/rustup.rs#toolchain-specification).
+This GitHub Action installs [Rust toolchain](https://rust-lang.github.io/rustup/concepts/toolchains.html#toolchain-specification)
+with [rustup](https://github.com/rust-lang/rustup) help.
 
-Optionally it can set installed toolchain as a default and as an override for current directory.
+It supports additional targets, components and profiles and handles all
+these small papercuts for you.
+
+**Table of Contents**
+
+* [Example workflow](#example-workflow)
+* [Inputs](#inputs)
+* [Outputs](#outputs)
+* [Profiles](#profiles)
+* [Components](#components)
+* [The toolchain file](#the-toolchain-file)
+* [License](#license)
+* [Contribute and support](#contribute-and-support)
 
 ## Example workflow
 
@@ -25,9 +41,10 @@ jobs:
         with:
             toolchain: nightly
             override: true
+            components: rustfmt, clippy
 
       # `cargo check` command here will use installed `nightly`
-      # as it set as an "override" for current directory
+      # as it is set as an "override" for current directory
 
       - name: Run cargo check
         uses: actions-rs/cargo@v1
@@ -41,11 +58,11 @@ See [additional recipes here](https://github.com/actions-rs/meta).
 
 | Name         | Required | Description                                                                                                                                         | Type   | Default |
 | ------------ | :------: | ----------------------------------------------------------------------------------------------------------------------------------------------------| ------ | --------|
-| `toolchain`  |          | [Toolchain](https://github.com/rust-lang/rustup.rs#toolchain-specification) name to use, ex. `stable`, `nightly`, `nightly-2019-04-20`, or `1.32.0` | string |         |
+| `toolchain`  |          | [Toolchain](https://github.com/rust-lang/rustup.rs#toolchain-specification) name to use, ex. `stable`, `nightly`, `nightly-2019-04-20`, or `1.32.0` | string | stable  |
 | `target`     |          | Additionally install specified target for this toolchain, ex. `x86_64-apple-darwin`                                                                 | string |         |
 | `default`    |          | Set installed toolchain as a default toolchain                                                                                                      | bool   | false   |
 | `override`   |          | Set installed toolchain as an override for the current directory                                                                                    | bool   | false   |
-| `profile`    |          | Execute `rustup set profile {value}` before installing the toolchain, ex. `minimal`                                                                 | string |         |
+| `profile`    |          | Execute `rustup set profile {value}` before installing the toolchain, ex. `minimal`                                                                 | string | default |
 | `components` |          | Comma-separated list of the additional components to install, ex. `clippy, rustfmt`                                                                 | string |         |
 
 Note: since `v1.0.4` version, `toolchain` input is not marked as required
@@ -62,7 +79,7 @@ Installed `rustc`, `cargo` and `rustup` versions can be fetched from the Action
 | `cargo`      | Cargo version         | `1.40.0 (bc8e4c8be 2019-11-22)` |
 | `rustup`     | rustup version        | `1.21.1 (7832b2ebe 2019-12-20)` |
 
-Note: `rustc-hash` output value can be used with [actions/cache](https://github.com/actions/cache) Action
+Note: `rustc_hash` output value can be used with [actions/cache](https://github.com/actions/cache) Action
 to store cache for different Rust versions, as it is unique across different Rust versions and builds (including `nightly`).
 
 ## Profiles
@@ -115,19 +132,38 @@ to install the minimal set of `nightly` toolchain components with the `rustfmt`
     components: rustfmt, clippy
 ```
 
-Same to the `profile` input, if the installed `rustup` does not supports "components",
+In case if `nightly` toolchain is requested and one of the components is missing in
+latest `nightly` release, this Action will attempt the downgrade till it find
+the most recent `nightly` with all components needed.\
+Note that this behavior will work only if the following two conditions apply:
+
+ 1. `toolchain` input is `nightly` exactly.
+ 2. At least one component is provided in `components` input.
+
+Same to the `profile` input, if installed `rustup` does not supports "components",
 it will be automatically upgraded by this Action.
 
 ## The toolchain file
 
-This Action supports [toolchain files](https://github.com/rust-lang/rustup#the-toolchain-file),
+This Action supports [toolchain files](https://rust-lang.github.io/rustup/overrides.html#the-toolchain-file),
 so it is not necessary to use `toolchain` input anymore.
 
-Input has higher priority, so if you are want to use toolchain file, you need to remove the input from the workflow file.
+Input has higher priority, so if you are want to use toolchain file,
+you need to remove the input from the workflow file.
 
-If neither `toolchain` input or `rust-toolchain` file are provided, Action execution will fail.
+If neither `toolchain` input or `rust-toolchain` file are provided,
+Action execution will fail.
 
-## Notes
+## License
 
-As `rustup` is not installed by default for [macOS environments](https://help.github.com/en/articles/virtual-environments-for-github-actions)
-at the moment (2019-09-13), this Action will try its best to install it before any other operations.
+This Action is distributed under the terms of the MIT license, see [LICENSE](https://github.com/actions-rs/toolchain/blob/master/LICENSE) for details.
+
+## Contribute and support
+
+Any contributions are welcomed!
+
+If you want to report a bug or have a feature request,
+check the [Contributing guide](https://github.com/actions-rs/.github/blob/master/CONTRIBUTING.md).
+
+You can also support author by funding the ongoing project work,
+see [Sponsoring](https://actions-rs.github.io/#sponsoring).

__tests__/args.test.ts

@@ -1,65 +1,74 @@
-import {toolchain_args} from "../src/args";
-import {morph} from "mock-env"
-import {sync as tempWriteSync} from "temp-write"
+import { getToolchainArgs } from "../src/args";
+import { morph } from "mock-env";
+import { sync as tempWriteSync } from "temp-write";
 
-describe('actions-rs/toolchain', () => {
-    it('Parses action input into toolchain options', async () => {
-        let args = morph(() => {
-            return toolchain_args("./rust-toolchain");
-        }, {
-            'INPUT_TOOLCHAIN': 'nightly-2019-04-20',
-            'INPUT_DEFAULT': 'false',
-            'INPUT_OVERRIDE': 'true'
-        });
+describe("actions-rs/toolchain", () => {
+    it("Parses action input into toolchain options", () => {
+        const args = morph(
+            () => {
+                return getToolchainArgs("./rust-toolchain");
+            },
+            {
+                INPUT_TOOLCHAIN: "nightly-2019-04-20",
+                INPUT_DEFAULT: "false",
+                INPUT_OVERRIDE: "true",
+            }
+        );
 
-        expect(args.name).toBe('nightly-2019-04-20');
+        expect(args.name).toBe("nightly-2019-04-20");
         expect(args.default).toBe(false);
         expect(args.override).toBe(true);
     });
 
-    it('uses input variable if rust-toolchain file does not exist', function () {
-        let args = morph(() => {
-            return toolchain_args("./rust-toolchain");
-        }, {
-            'INPUT_TOOLCHAIN': 'nightly',
-        });
+    it("uses input variable if rust-toolchain file does not exist", function () {
+        const args = morph(
+            () => {
+                return getToolchainArgs("./rust-toolchain");
+            },
+            {
+                INPUT_TOOLCHAIN: "nightly",
+            }
+        );
 
-        expect(args.name).toBe("nightly")
+        expect(args.name).toBe("nightly");
     });
 
-    it('toolchain input is required if rust-toolchain does not exist', function () {
-        expect(() => toolchain_args("./rust-toolchain")).toThrowError()
+    it("toolchain input is required if rust-toolchain does not exist", function () {
+        expect(() => getToolchainArgs("./rust-toolchain")).toThrowError();
     });
 
-    it('prioritizes rust-toolchain file over input variable', function () {
-        let rustToolchainFile = tempWriteSync("1.39.0");
+    it("prioritizes rust-toolchain file over input variable", function () {
+        const rustToolchainFile = tempWriteSync("1.39.0");
 
-        let args = morph(() => {
-            return toolchain_args(rustToolchainFile);
-        }, {
-            'INPUT_TOOLCHAIN': 'nightly',
-        });
+        const args = morph(
+            () => {
+                return getToolchainArgs(rustToolchainFile);
+            },
+            {
+                INPUT_TOOLCHAIN: "nightly",
+            }
+        );
 
-        expect(args.name).toBe("nightly")
+        expect(args.name).toBe("nightly");
     });
 
-    it('uses rust-toolchain file if input does not exist', function () {
-        let rustToolchainFile = tempWriteSync("1.39.0");
+    it("uses rust-toolchain file if input does not exist", function () {
+        const rustToolchainFile = tempWriteSync("1.39.0");
 
-        let args = morph(() => {
-            return toolchain_args(rustToolchainFile);
+        const args = morph(() => {
+            return getToolchainArgs(rustToolchainFile);
         }, {});
 
-        expect(args.name).toBe("1.39.0")
+        expect(args.name).toBe("1.39.0");
     });
 
-    it('trims content of the override file', function () {
-        let rustToolchainFile = tempWriteSync("\n     1.39.0\n\n\n\n");
+    it("trims content of the override file", function () {
+        const rustToolchainFile = tempWriteSync("\n     1.39.0\n\n\n\n");
 
-        let args = morph(() => {
-            return toolchain_args(rustToolchainFile);
+        const args = morph(() => {
+            return getToolchainArgs(rustToolchainFile);
         }, {});
 
-        expect(args.name).toBe("1.39.0")
+        expect(args.name).toBe("1.39.0");
     });
 });

action.yml

@@ -9,7 +9,7 @@ inputs:
     description: |
       Rust toolchain name.
 
-      See https://github.com/rust-lang/rustup.rs#toolchain-specification
+      See https://rust-lang.github.io/rustup/concepts/toolchains.html#toolchain-specification
 
       If this is not given, the action will try and install the version specified in the `rust-toolchain` file.
     required: false

jest.config.js

@@ -1,11 +0,0 @@
-module.exports = {
-  clearMocks: true,
-  moduleFileExtensions: ['js', 'ts'],
-  testEnvironment: 'node',
-  testMatch: ['**/*.test.ts'],
-  testRunner: 'jest-circus/runner',
-  transform: {
-    '^.+\\.ts$': 'ts-jest'
-  },
-  verbose: true
-}

jest.config.json

@@ -0,0 +1,11 @@
+{
+  "clearMocks": true,
+  "moduleFileExtensions": ["js", "ts"],
+  "testEnvironment": "node",
+  "testMatch": ["**/*.test.ts"],
+  "testRunner": "jest-circus/runner",
+  "transform": {
+    "^.+\\.ts$": "ts-jest"
+  },
+  "verbose": true
+}

package.json

@@ -1,6 +1,6 @@
 {
     "name": "rust-toolchain",
-    "version": "1.0.5",
+    "version": "1.0.7",
     "private": false,
     "description": "Install the Rust toolchain",
     "main": "lib/main.js",
@@ -9,10 +9,12 @@
         "test": "__tests__"
     },
     "scripts": {
-        "build": "ncc build src/main.ts --minify",
-        "watch": "ncc build src/main.ts --watch",
-        "pretest": "git config core.hooksPath .githooks",
-        "test": "jest"
+        "build": "rm -rf ./dist/* && ncc build src/main.ts --minify",
+        "format": "prettier --write 'src/**/*.ts' '__tests__/**/*.ts'",
+        "lint": "tsc --noEmit && eslint 'src/**/*.ts' '__tests__/**/*.ts'",
+        "watch": "rm -rf ./dist/* && ncc build src/main.ts --watch",
+        "test": "jest -c jest.config.json",
+        "pretest": "git config core.hooksPath .githooks"
     },
     "repository": {
         "type": "git",
@@ -30,21 +32,27 @@
         "url": "https://github.com/actions-rs/toolchain/issues"
     },
     "dependencies": {
-        "@actions-rs/core": "^0.0.8",
-        "@actions/core": "^1.2.2",
-        "@actions/exec": "^1.0.3",
-        "@actions/io": "^1.0.2",
-        "npm-check-updates": "^4.0.1"
+        "@actions-rs/core": "^0.1.6",
+        "@actions/core": "^1.2.6",
+        "@actions/exec": "^1.0.4",
+        "@actions/io": "^1.0.2"
     },
     "devDependencies": {
-        "temp-write": "^4.0.0",
-        "@types/jest": "^24.9.1",
-        "@types/node": "^13.5.0",
-        "@zeit/ncc": "^0.21.0",
-        "jest": "^25.1.0",
-        "jest-circus": "^25.1.0",
+        "@types/jest": "^26.0.15",
+        "@types/node": "^14.14.7",
+        "@typescript-eslint/eslint-plugin": "^4.8.1",
+        "@typescript-eslint/parser": "^4.8.1",
+        "@zeit/ncc": "^0.22.3",
+        "eslint": "^7.13.0",
+        "eslint-config-prettier": "^6.15.0",
+        "eslint-plugin-prettier": "^3.1.4",
+        "jest": "^26.6.3",
+        "jest-circus": "^26.6.3",
         "mock-env": "^0.2.0",
-        "ts-jest": "^25.0.0",
-        "typescript": "^3.7.5"
+        "npm-check-updates": "^10.2.1",
+        "prettier": "^2.1.2",
+        "temp-write": "^4.0.0",
+        "ts-jest": "^26.4.4",
+        "typescript": "^4.0.5"
     }
 }

src/args.ts

@@ -1,51 +1,52 @@
-import {input} from '@actions-rs/core';
-import {info, debug} from "@actions/core";
-import {existsSync, readFileSync} from 'fs';
+import { input } from "@actions-rs/core";
+import { debug } from "@actions/core";
+import { existsSync, readFileSync } from "fs";
 
 export interface ToolchainOptions {
-    name: string,
-    target: string | undefined,
-    default: boolean,
-    override: boolean,
-    profile: string | undefined,
-    components: string[] | undefined,
-}
-
-export function toolchain_args(overrideFile: string): ToolchainOptions {
-    let components: string[] | undefined = input.getInputList('components');
-    if (components && components.length === 0) {
-        components = undefined;
-    }
-
-    return {
-        name: determineToolchain(overrideFile),
-        target: input.getInput('target') || undefined,
-        default: input.getInputBool('default'),
-        override: input.getInputBool('override'),
-        profile: input.getInput('profile') || undefined,
-        components: components,
-    };
+    name: string;
+    target: string | undefined;
+    default: boolean;
+    override: boolean;
+    profile: string | undefined;
+    components: string[] | undefined;
 }
 
 function determineToolchain(overrideFile: string): string {
-
-    const toolchainInput = input.getInput('toolchain', {required: false});
+    const toolchainInput = input.getInput("toolchain", { required: false });
 
     if (toolchainInput) {
         debug(`using toolchain from input: ${toolchainInput}`);
-        return toolchainInput
+        return toolchainInput;
     }
 
     if (!existsSync(overrideFile)) {
-        throw new Error("toolchain input was not given and repository does not have a rust-toolchain file")
+        throw new Error(
+            "toolchain input was not given and repository does not have a rust-toolchain file"
+        );
     }
 
     const rustToolchainFile = readFileSync(overrideFile, {
         encoding: "utf-8",
-        flag: "r"
+        flag: "r",
     }).trim();
 
     debug(`using toolchain from rust-toolchain file: ${rustToolchainFile}`);
 
     return rustToolchainFile;
 }
+
+export function getToolchainArgs(overrideFile: string): ToolchainOptions {
+    let components: string[] | undefined = input.getInputList("components");
+    if (components && components.length === 0) {
+        components = undefined;
+    }
+
+    return {
+        name: determineToolchain(overrideFile),
+        target: input.getInput("target") || undefined,
+        default: input.getInputBool("default"),
+        override: input.getInputBool("override"),
+        profile: input.getInput("profile") || undefined,
+        components: components,
+    };
+}

src/main.ts

@@ -1,29 +1,27 @@
-import * as core from '@actions/core';
-import * as exec from '@actions/exec';
-import * as io from '@actions/io';
+import * as core from "@actions/core";
 import path from "path";
 
-import * as args from './args';
-import * as versions from './versions';
-import {RustUp, ToolchainOptions} from '@actions-rs/core';
+import * as args from "./args";
+import * as versions from "./versions";
+import { RustUp, ToolchainOptions } from "@actions-rs/core";
 
-async function run() {
+async function run(): Promise<void> {
     // we use path.join to make sure this works on Windows, Linux and MacOS
-    let toolchainOverrideFile = path.join(process.cwd(), "rust-toolchain");
+    const toolchainOverridePath = path.join(process.cwd(), "rust-toolchain");
 
-    const opts = args.toolchain_args(toolchainOverrideFile);
+    const opts = args.getToolchainArgs(toolchainOverridePath);
     const rustup = await RustUp.getOrInstall();
-    await rustup.call(['show']);
+    await rustup.call(["show"]);
 
     let shouldSelfUpdate = false;
-    if (opts.profile && !await rustup.supportProfiles()) {
+    if (opts.profile && !(await rustup.supportProfiles())) {
         shouldSelfUpdate = true;
     }
-    if (opts.components && !await rustup.supportComponents()) {
+    if (opts.components && !(await rustup.supportComponents())) {
         shouldSelfUpdate = true;
     }
     if (shouldSelfUpdate) {
-        core.startGroup('Updating rustup');
+        core.startGroup("Updating rustup");
         try {
             await rustup.selfUpdate();
         } finally {
@@ -32,11 +30,11 @@ async function run() {
     }
 
     if (opts.profile) {
-        //@ts-ignore
+        // @ts-ignore: TS2345
         await rustup.setProfile(opts.profile);
     }
 
-    let installOptions: ToolchainOptions = {
+    const installOptions: ToolchainOptions = {
         default: opts.default,
         override: opts.override,
     };
@@ -48,6 +46,37 @@ async function run() {
     if (shouldSelfUpdate) {
         installOptions.noSelfUpdate = true;
     }
+
+    // Extra funny case.
+    // Due to `rustup` issue (https://github.com/rust-lang/rustup/issues/2146)
+    // right now installing `nightly` toolchain with extra components might fail
+    // if that specific `nightly` version does not have this component
+    // available.
+    //
+    // See https://github.com/actions-rs/toolchain/issues/53 also.
+    //
+    // By default `rustup` does not downgrade, as it does when you are
+    // updating already installed `nightly`, so we need to pass the
+    // corresponding flag manually.
+    //
+    // We are doing it only if both following conditions apply:
+    //
+    //   1. Requested toolchain is `"nightly"` (exact string match).
+    //   2. At least one component is requested.
+    //
+    // All other cases are not triggering automatic downgrade,
+    // for example, installing specific nightly version
+    // as in `"nightly-2020-03-20"` or `"stable"`.
+    //
+    // Motivation is that users probably want the latest one nightly
+    // with rustfmt and clippy (miri, etc) and they don't really care
+    // about what exact nightly it is.
+    // In case if it's not the nightly at all or it is a some specific
+    // nightly version, they know what they are doing.
+    if (opts.name == "nightly" && opts.components) {
+        installOptions.allowDowngrade = true;
+    }
+
     await rustup.installToolchain(opts.name, installOptions);
 
     if (opts.target) {
@@ -57,7 +86,7 @@ async function run() {
     await versions.gatherInstalledVersions();
 }
 
-async function main() {
+async function main(): Promise<void> {
     try {
         await run();
     } catch (error) {

src/versions.ts

@@ -1,61 +1,9 @@
-import * as exec from '@actions/exec';
-import * as core from '@actions/core';
-
-export async function gatherInstalledVersions(): Promise<void> {
-    try {
-        core.startGroup('Gathering installed versions');
-
-        await rustc();
-        await cargo();
-        await rustup();
-    } finally {
-        core.endGroup();
-    }
-}
-
-/**
- * Fetch currently used `rustc` version
- */
-async function rustc(): Promise<void> {
-    const stdout = await getStdout('rustc', ['-V']);
-    try {
-        const version = parseFull(stdout);
-
-        core.setOutput('rustc', version.long);
-        core.setOutput('rustc_hash', version.hash);
-    } catch(e) {
-        core.warning(e);
-        core.setOutput('rustc', parseShort(stdout));
-    }
-}
-
-/**
- * Fetch currently used `cargo` version
- */
-async function cargo(): Promise<void> {
-    const stdout = await getStdout('cargo', ['-V']);
-    try {
-        const version = parseFull(stdout);
-
-        core.setOutput('cargo', version.long);
-    } catch(e) {
-        core.setOutput('cargo', parseShort(stdout));
-    }
-}
-
-async function rustup(): Promise<void> {
-    const stdout = await getStdout('rustup', ['-V']);
-    try {
-        const version = parseFull(stdout);
-        core.setOutput('rustup', version.long);
-    } catch(e) {
-        core.setOutput('rustup', parseShort(stdout));
-    }
-}
+import * as exec from "@actions/exec";
+import * as core from "@actions/core";
 
 interface Version {
-    long: string,
-    hash: string,
+    long: string;
+    hash: string;
 }
 
 /**
@@ -69,8 +17,9 @@ interface Version {
  * As a fallback, `parseShort` function can be used.
  */
 function parseFull(stdout: string): Version {
+    const regex = /\S+\s((\S+)\s\((\S+)\s(\S+)\))/m;
     stdout = stdout.trim();
-    const matches = stdout.match(/\S+\s((\S+)\s\((\S+)\s(\S+)\))/m);
+    const matches = regex.exec(stdout);
     if (matches == null) {
         throw new Error(`Unable to parse version from the "${stdout}" string`);
     }
@@ -78,25 +27,30 @@ function parseFull(stdout: string): Version {
     return {
         long: matches[1],
         hash: matches[3],
-    }
+    };
 }
 
 function parseShort(stdout: string): string {
+    const regex = /\S+\s(.+)/m;
     stdout = stdout.trim();
-    const matches = stdout.match(/\S+\s(.+)/m);
+    const matches = regex.exec(stdout);
     if (matches == null) {
         core.warning(`Unable to determine version from the "${stdout}" string`);
-        return '';
+        return "";
     } else {
         return matches[1];
     }
 }
 
-async function getStdout(exe: string, args: string[], options?: {}): Promise<string> {
-    let stdout = '';
+async function getStdout(
+    exe: string,
+    args: string[],
+    options?: {}
+): Promise<string> {
+    let stdout = "";
     const resOptions = Object.assign({}, options, {
         listeners: {
-            stdout: (buffer: Buffer) => {
+            stdout: (buffer: Buffer): void => {
                 stdout += buffer.toString();
             },
         },
@@ -106,3 +60,55 @@ async function getStdout(exe: string, args: string[], options?: {}): Promise<str
 
     return stdout;
 }
+
+/**
+ * Fetch currently used `rustc` version
+ */
+async function rustc(): Promise<void> {
+    const stdout = await getStdout("rustc", ["-V"]);
+    try {
+        const version = parseFull(stdout);
+
+        core.setOutput("rustc", version.long);
+        core.setOutput("rustc_hash", version.hash);
+    } catch (e) {
+        core.warning(e);
+        core.setOutput("rustc", parseShort(stdout));
+    }
+}
+
+/**
+ * Fetch currently used `cargo` version
+ */
+async function cargo(): Promise<void> {
+    const stdout = await getStdout("cargo", ["-V"]);
+    try {
+        const version = parseFull(stdout);
+
+        core.setOutput("cargo", version.long);
+    } catch (e) {
+        core.setOutput("cargo", parseShort(stdout));
+    }
+}
+
+async function rustup(): Promise<void> {
+    const stdout = await getStdout("rustup", ["-V"]);
+    try {
+        const version = parseFull(stdout);
+        core.setOutput("rustup", version.long);
+    } catch (e) {
+        core.setOutput("rustup", parseShort(stdout));
+    }
+}
+
+export async function gatherInstalledVersions(): Promise<void> {
+    try {
+        core.startGroup("Gathering installed versions");
+
+        await rustc();
+        await cargo();
+        await rustup();
+    } finally {
+        core.endGroup();
+    }
+}

tsconfig.eslint.json

@@ -0,0 +1,7 @@
+{
+    "extends": "./tsconfig.json",
+    "include": [
+        "src/**/*.ts",
+        "__tests__/**/*.ts"
+    ]
+}

tsconfig.json

@@ -1,63 +1,32 @@
 {
-  "compilerOptions": {
-    /* Basic Options */
-    // "incremental": true,                   /* Enable incremental compilation */
-    "target": "es6",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
-    "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
-    // "allowJs": true,                       /* Allow javascript files to be compiled. */
-    // "checkJs": true,                       /* Report errors in .js files. */
-    // "jsx": "preserve",                     /* Specify JSX code generation: 'preserve', 'react-native', or 'react'. */
-    // "declaration": true,                   /* Generates corresponding '.d.ts' file. */
-    // "declarationMap": true,                /* Generates a sourcemap for each corresponding '.d.ts' file. */
-    // "sourceMap": true,                     /* Generates corresponding '.map' file. */
-    // "outFile": "./",                       /* Concatenate and emit output to single file. */
-    "outDir": "./lib",                        /* Redirect output structure to the directory. */
-    "rootDir": "./src",                       /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
-    // "composite": true,                     /* Enable project compilation */
-    // "tsBuildInfoFile": "./",               /* Specify file to store incremental compilation information */
-    // "removeComments": true,                /* Do not emit comments to output. */
-    // "noEmit": true,                        /* Do not emit outputs. */
-    // "importHelpers": true,                 /* Import emit helpers from 'tslib'. */
-    // "downlevelIteration": true,            /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */
-    // "isolatedModules": true,               /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */
-
-    /* Strict Type-Checking Options */
-    "strict": true,                           /* Enable all strict type-checking options. */
-    "noImplicitAny": false,                 /* Raise error on expressions and declarations with an implied 'any' type. */
-    // "strictNullChecks": true,              /* Enable strict null checks. */
-    // "strictFunctionTypes": true,           /* Enable strict checking of function types. */
-    // "strictBindCallApply": true,           /* Enable strict 'bind', 'call', and 'apply' methods on functions. */
-    // "strictPropertyInitialization": true,  /* Enable strict checking of property initialization in classes. */
-    // "noImplicitThis": true,                /* Raise error on 'this' expressions with an implied 'any' type. */
-    // "alwaysStrict": true,                  /* Parse in strict mode and emit "use strict" for each source file. */
-
-    /* Additional Checks */
-    // "noUnusedLocals": true,                /* Report errors on unused locals. */
-    // "noUnusedParameters": true,            /* Report errors on unused parameters. */
-    // "noImplicitReturns": true,             /* Report error when not all code paths in function return a value. */
-    // "noFallthroughCasesInSwitch": true,    /* Report errors for fallthrough cases in switch statement. */
-
-    /* Module Resolution Options */
-    // "moduleResolution": "node",            /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */
-    // "baseUrl": "./",                       /* Base directory to resolve non-absolute module names. */
-    // "paths": {},                           /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
-    // "rootDirs": [],                        /* List of root folders whose combined content represents the structure of the project at runtime. */
-    // "typeRoots": [],                       /* List of folders to include type definitions from. */
-    // "types": [],                           /* Type declaration files to be included in compilation. */
-    // "allowSyntheticDefaultImports": true,  /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
-    "esModuleInterop": true                   /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
-    // "preserveSymlinks": true,              /* Do not resolve the real path of symlinks. */
-    // "allowUmdGlobalAccess": true,          /* Allow accessing UMD globals from modules. */
-
-    /* Source Map Options */
-    // "sourceRoot": "",                      /* Specify the location where debugger should locate TypeScript files instead of source locations. */
-    // "mapRoot": "",                         /* Specify the location where debugger should locate map files instead of generated locations. */
-    // "inlineSourceMap": true,               /* Emit a single file with source maps instead of having a separate file. */
-    // "inlineSources": true,                 /* Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set. */
-
-    /* Experimental Options */
-    // "experimentalDecorators": true,        /* Enables experimental support for ES7 decorators. */
-    // "emitDecoratorMetadata": true,         /* Enables experimental support for emitting type metadata for decorators. */
-  },
-  "exclude": ["node_modules", "**/*.test.ts"]
+    "compilerOptions": {
+        "allowJs": false,
+        "checkJs": false,
+        "esModuleInterop": true,
+        "forceConsistentCasingInFileNames": true,
+        "module": "commonjs",
+        "moduleResolution": "node",
+        "newLine": "LF",
+        "noEmitOnError": true,
+        "noErrorTruncation": true,
+        "noFallthroughCasesInSwitch": true,
+        "noImplicitAny": true,
+        "noImplicitReturns": true,
+        "noImplicitThis": true,
+        "noUnusedLocals": true,
+        "noUnusedParameters": true,
+        "outDir": "dist",
+        "pretty": true,
+        "removeComments": true,
+        "resolveJsonModule": true,
+        "strict": true,
+        "suppressImplicitAnyIndexErrors": false,
+        "target": "es2018",
+        "declaration": false,
+        "sourceMap": false,
+        "typeRoots": ["./types", "./node_modules/@types"]
+    },
+    "include": [
+        "src/**/*.ts"
+    ]
 }

types/mock-env/index.d.ts

@@ -3,5 +3,5 @@ declare module "mock-env" {
         callback: () => T,
         vars: object,
         toRemove?: string[]
-    )
+    ): any;
 }