Add golint support

.github/workflows/test.yml

@@ -23,6 +23,18 @@ jobs:
         with:
           go-version: 1.13
 
+      # TODO: Remove step once actions/setup-go adds $GOPATH/bin to $PATH by default
+      # See https://github.com/actions/setup-go/issues/14
+      - name: Add Go to $PATH
+        run: |
+          echo "::set-env name=GOPATH::$(go env GOPATH)"
+          echo "::add-path::$(go env GOPATH)/bin"
+
+      - name: Install Go dependencies
+        run: |
+          cd ./test/linters/projects/golint
+          go get -u golang.org/x/lint/golint
+
       # Node.js
 
       - name: Install Node.js and Yarn

README.md

@@ -16,6 +16,7 @@ This action…
 
 - **Go:**
   - [gofmt](https://golang.org/cmd/gofmt)
+  - [golint](https://github.com/golang/lint)
 - **JavaScript:**
   - [ESLint](https://eslint.org)
   - [Prettier](https://prettier.io)
@@ -133,7 +134,7 @@ All linters are disabled by default. To enable a linter, simply set the option w
     eslint: true # Enables ESLint checks
 ```
 
-`[linter]` can be one of `black`, `eslint`, `flake8`, `gofmt`, `prettier`, `stylelint`, and `swiftlint`:
+`[linter]` can be one of `black`, `eslint`, `flake8`, `gofmt`, `golint`, `prettier`, `stylelint`, and `swiftlint`:
 
 - **`[linter]`:** Enables the linter in your repository. Default: `false`
 - **`[linter]_extensions`:** Extensions of files to check with the linter. Example: `eslint_extensions: js,ts` to lint both JavaScript and TypeScript files with ESLint. Default: See [`action.yml`](./action.yml)

action.yml

@@ -36,6 +36,18 @@ inputs:
     description: Directory where the gofmt command should be run
     required: false
 
+  golint:
+    description: Enable or disable golint checks
+    required: false
+    default: false
+  golint_extensions:
+    description: Extensions of files to check with golint
+    required: false
+    default: "go"
+  golint_dir:
+    description: Directory where the golint command should be run
+    required: false
+
   # JavaScript
 
   eslint:

src/linters/flake8.js

@@ -41,7 +41,7 @@ class Flake8 {
 	 */
 	static lint(dir, extensions, fix = false) {
 		if (fix) {
-			log(`${this.name} does not support auto-fixing code style issues`, "warning");
+			log(`${this.name} does not support auto-fixing`, "warning");
 		}
 		return run(`flake8 --filename ${extensions.map(ext => `"**${sep}*.${ext}"`).join(",")}`, {
 			dir,

src/linters/golint.js

@@ -0,0 +1,78 @@
+const commandExists = require("../../vendor/command-exists");
+const { log, run } = require("../utils/action");
+const { capitalizeFirstLetter } = require("../utils/string");
+
+const PARSE_REGEX = /^(.+):([0-9]+):([0-9]+): (.+)$/gm;
+
+/**
+ * https://github.com/golang/lint
+ */
+class Golint {
+	static get name() {
+		return "golint";
+	}
+
+	/**
+	 * Verifies that all required programs are installed. Exits the GitHub action if one of the
+	 * programs is missing
+	 *
+	 * @param {string} dir: Directory to run the linting program in
+	 */
+	static async verifySetup(dir) {
+		// Verify that golint is installed
+		if (!(await commandExists("golint"))) {
+			throw new Error(`${this.name} is not installed`);
+		}
+	}
+
+	/**
+	 * Runs the linting program and returns the command output
+	 *
+	 * @param {string} dir: Directory to run the linting program in
+	 * @param {string[]} extensions: Array of file extensions which should be linted
+	 * @param {boolean} fix: Whether the linter should attempt to fix code style issues automatically
+	 * @returns {string}: Results of the linting process
+	 */
+	static lint(dir, extensions, fix = false) {
+		if (extensions.length !== 1 || extensions[0] !== "go") {
+			throw new Error(`${this.name} error: File extensions are not configurable`);
+		}
+
+		if (fix) {
+			log(`${this.name} does not support auto-fixing`, "warning");
+		}
+		return run(`golint "."`, {
+			dir,
+			ignoreErrors: true,
+		}).stdout;
+	}
+
+	/**
+	 * Parses the results of the linting process and returns it as a processable array
+	 *
+	 * @param {string} dir: Directory in which the linting program has been run
+	 * @param {string} results: Results of the linting process
+	 * @returns {object[]}: Parsed results
+	 */
+	static parseResults(dir, results) {
+		const matches = results.matchAll(PARSE_REGEX);
+
+		// Parsed results: [notices, warnings, failures]
+		const resultsParsed = [[], [], []];
+
+		for (const match of matches) {
+			const [_str, path, line, _column, text] = match;
+			const lineNr = parseInt(line, 10);
+			resultsParsed[2].push({
+				path,
+				firstLine: lineNr,
+				lastLine: lineNr,
+				message: capitalizeFirstLetter(text),
+			});
+		}
+
+		return resultsParsed;
+	}
+}
+
+module.exports = Golint;

test/linters/linters.test.js

@@ -6,6 +6,7 @@ const eslintParams = require("./params/eslint");
 const eslintTypescriptParams = require("./params/eslint-typescript");
 const flake8Params = require("./params/flake8");
 const gofmtParams = require("./params/gofmt");
+const golintParams = require("./params/golint");
 const prettierParams = require("./params/prettier");
 const stylelintParams = require("./params/stylelint");
 const swiftlintParams = require("./params/swiftlint");
@@ -16,6 +17,7 @@ const linterParams = [
 	eslintTypescriptParams,
 	flake8Params,
 	gofmtParams,
+	golintParams,
 	prettierParams,
 	stylelintParams,
 ];

test/linters/params/golint.js

@@ -0,0 +1,46 @@
+const Golint = require("../../../src/linters/golint");
+
+const testName = "golint";
+const linter = Golint;
+const extensions = ["go"];
+
+const getLintResults = dir => {
+	const resultsFile1 =
+		"file1.go:14:9: if block ends with a return statement, so drop this else and outdent its block";
+	const resultsFile2 =
+		'file2.go:3:1: comment on exported function Divide should be of the form "Divide ..."';
+	return [`${resultsFile1}\n${resultsFile2}`, `${resultsFile2}\n${resultsFile1}`];
+};
+
+const parsedLintResults = [
+	[],
+	[],
+	[
+		{
+			path: "file1.go",
+			firstLine: 14,
+			lastLine: 14,
+			message: `If block ends with a return statement, so drop this else and outdent its block`,
+		},
+		{
+			path: "file2.go",
+			firstLine: 3,
+			lastLine: 3,
+			message: `Comment on exported function Divide should be of the form "Divide ..."`,
+		},
+	],
+];
+
+const getFixResults = getLintResults;
+
+const parsedFixResults = parsedLintResults;
+
+module.exports = [
+	testName,
+	linter,
+	extensions,
+	getLintResults,
+	getFixResults,
+	parsedLintResults,
+	parsedFixResults,
+];

test/linters/projects/golint/file1.go

@@ -0,0 +1,18 @@
+package main
+
+import "fmt"
+
+var str = "world"
+
+func main() {
+	fmt.Println("hello " + doSomething(str))
+}
+
+func doSomething(str string) string {
+	if str == "" {
+		return "default"
+	} else {
+		// Error for unnecessary "else" statement
+		return str
+	}
+}

test/linters/projects/golint/file2.go

@@ -0,0 +1,6 @@
+package main
+
+// Error for incorrect comment format
+func Divide(num1 int, num2 int) int {
+	return num1 / num2
+}