feat(cli): Support GitHub workflow commands (#326)

Author: Thiry1

cmd/rslint/cmd.go

@@ -11,6 +11,7 @@ import (
 	"runtime/pprof"
 	"runtime/trace"
 	"strconv"
+	"strings"
 	"sync"
 	"time"
 	"unicode"
@@ -87,11 +88,53 @@ func printDiagnostic(d rule.RuleDiagnostic, w *bufio.Writer, comparePathOptions
 		printDiagnosticDefault(d, w, comparePathOptions)
 	case "jsonline":
 		printDiagnosticJsonLine(d, w, comparePathOptions)
+	case "github":
+		printDiagnosticGitHub(d, w, comparePathOptions)
 	default:
 		panic("not supported format " + format)
 	}
 }
 
+// print as [Workflow commands for GitHub Actions](https://docs.github.com/en/actions/reference/workflows-and-actions/workflow-commands) format
+func printDiagnosticGitHub(d rule.RuleDiagnostic, w *bufio.Writer, comparePathOptions tspath.ComparePathsOptions) {
+	diagnosticStart := d.Range.Pos()
+	diagnosticEnd := d.Range.End()
+
+	startLine, startColumn := scanner.GetLineAndCharacterOfPosition(d.SourceFile, diagnosticStart)
+	endLine, endColumn := scanner.GetLineAndCharacterOfPosition(d.SourceFile, diagnosticEnd)
+
+	filePath := tspath.ConvertToRelativePath(d.SourceFile.FileName(), comparePathOptions)
+	output := fmt.Sprintf(
+		"::%s file=%s,line=%d,endLine=%d,col=%d,endColumn=%d,title=%s::%s\n",
+		d.Severity.String(),
+		escapeProperty(filePath),
+		startLine+1,
+		endLine+1,
+		startColumn+1,
+		endColumn+1,
+		d.RuleName,
+		escapeData(d.Message.Description),
+	)
+	w.WriteString(output)
+}
+
+func escapeData(str string) string {
+	// https://github.com/biomejs/biome/blob/4416573f4d709047a28407d99381810b7bc7dcc7/crates/biome_diagnostics/src/display_github.rs#L85C4-L85C15
+	str = strings.ReplaceAll(str, "%", "%25")
+	str = strings.ReplaceAll(str, "\r", "%0D")
+	str = strings.ReplaceAll(str, "\n", "%0A")
+	return str
+}
+func escapeProperty(str string) string {
+	// https://github.com/biomejs/biome/blob/4416573f4d709047a28407d99381810b7bc7dcc7/crates/biome_diagnostics/src/display_github.rs#L103
+	str = strings.ReplaceAll(str, "%", "%25")
+	str = strings.ReplaceAll(str, "\r", "%0D")
+	str = strings.ReplaceAll(str, "\n", "%0A")
+	str = strings.ReplaceAll(str, ":", "%3A")
+	str = strings.ReplaceAll(str, ",", "%2C")
+	return str
+}
+
 // print as [jsonline](https://jsonlines.org/) format which can be used for lsp
 func printDiagnosticJsonLine(d rule.RuleDiagnostic, w *bufio.Writer, comparePathOptions tspath.ComparePathsOptions) {
 	diagnosticStart := d.Range.Pos()
@@ -316,7 +359,7 @@ Usage:
 Options:
   --init				Initialize a default config in the current directory.
   --config PATH         Which rslint config file to use. Defaults to rslint.json.
-  --format FORMAT       Output format: default | jsonline
+  --format FORMAT       Output format: default | jsonline | github
   --fix                 Automatically fix problems
   --no-color            Disable colored output
   --force-color         Force colored output

packages/rslint-test-tools/rstest.config.mts

@@ -4,6 +4,9 @@ export default defineConfig({
   testEnvironment: 'node',
   globals: true,
   include: [
+    // cli
+    './tests/cli/basic.test.ts',
+
     // eslint-plugin-import
     './tests/eslint-plugin-import/rules/no-self-import.test.ts',
 

packages/rslint-test-tools/tests/cli/basic.test.ts

@@ -211,6 +211,58 @@ describe('CLI Configuration Tests', () => {
     }
   });
 
+  test('should output in github workflow format when --format github is used', async () => {
+    const tempDir = await createTempDir({
+      'rslint.json': JSON.stringify([
+        {
+          language: 'javascript',
+          files: ['**/*.ts'],
+          languageOptions: {
+            parserOptions: {
+              projectService: false,
+              project: ['./tsconfig.json'],
+            },
+          },
+          rules: {
+            '@typescript-eslint/no-unsafe-member-access': 'error',
+          },
+          plugins: ['@typescript-eslint'],
+        },
+      ]),
+      'tsconfig.json': JSON.stringify({
+        compilerOptions: {
+          target: 'ES2020',
+          module: 'ESNext',
+          strict: true,
+        },
+        include: ['**/*.ts'],
+      }),
+      'test:%,\r\nfile.ts': `
+        let a: any = 10;
+        a.b = 20;
+      `,
+    });
+
+    try {
+      const result = await runRslint(['--format', 'github'], tempDir);
+
+      const lines = result.stdout
+        .trim()
+        .split('\n')
+        .filter(line => line.trim());
+
+      expect(lines.length).toBe(2);
+      expect(lines[0]).toBe(
+        '::error file=test%3A%25%2C%0D%0Afile.ts,line=2,endLine=2,col=16,endColumn=19,title=@typescript-eslint/no-explicit-any::Unexpected any. Specify a different type.',
+      );
+      expect(lines[1]).toBe(
+        '::error file=test%3A%25%2C%0D%0Afile.ts,line=3,endLine=3,col=11,endColumn=12,title=@typescript-eslint/no-unsafe-member-access::Unsafe member access .b on an `any` value.',
+      );
+    } finally {
+      await cleanupTempDir(tempDir);
+    }
+  });
+
   test('should only report errors when --quiet flag is used', async () => {
     const tempDir = await createTempDir({
       'rslint.json': JSON.stringify([