feat: add Justfile validation via embedded go-just module (#454)

Adds Justfile as the 16th supported file type. Validates .just files and
known filenames (justfile, Justfile, .justfile) using a pure Go parser
embedded as a nested module at pkg/validator/justfile/.

The nested module has its own go.mod and can be extracted to a standalone
repo later by updating the replace directive.

CI pipelines updated to run vet, fmt, lint, and tests on both the root
module and the nested go-just module.

Author: kehoecj

.github/workflows/go.yml

@@ -50,10 +50,14 @@ jobs:
           go-version: "1.26"
 
       - name: Static Analysis
-        run: go vet ./...
+        run: |
+          go vet ./...
+          cd pkg/validator/justfile && go vet ./...
 
       - name: Check Formatting
-        run: test -z "$(gofmt -s -l -e .)"
+        run: |
+          test -z "$(gofmt -s -l -e .)"
+          cd pkg/validator/justfile && test -z "$(gofmt -s -l -e .)"
 
       - name: Check generated files are up to date
         run: |
@@ -106,7 +110,9 @@ jobs:
           go-version: "1.26"
 
       - name: Unit test
-        run: go test -v -cover -coverprofile coverage.out ./...
+        run: |
+          go test -v -cover -coverprofile coverage.out ./...
+          cd pkg/validator/justfile && go test -v -count=1 ./...
 
       - name: Check coverage
         id: check-coverage

.github/workflows/golangci-lint.yml

@@ -52,8 +52,12 @@ jobs:
           # The location of the configuration file can be changed by using `--config=`
           args: --timeout=10m
 
-          # Optional: show only new issues if it's a pull request. The default value is `false`.
-          # only-new-issues: true
+          install-mode: "goinstall"
 
-          # Optional:The mode to install golangci-lint. It can be 'binary' or 'goinstall'.
+      - name: golangci-lint (go-just nested module)
+        uses: golangci/golangci-lint-action@1e7e51e771db61008b38414a730f564565cf7c20 # v9.2.0
+        with:
+          version: v2.11.4
+          working-directory: pkg/validator/justfile
+          args: --timeout=10m
           install-mode: "goinstall"

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Justfile syntax validation (`.just`, `justfile`, `Justfile`, `.justfile`) via embedded [go-just](https://github.com/Boeing/go-just) parser
 - `--gitignore` flag to skip files and directories matched by `.gitignore` patterns, including nested `.gitignore` files, `.git/info/exclude`, and global git ignore config. Supported via CLI flag, `CFV_GITIGNORE` env var, and `gitignore = true` in `.cfv.toml`.
 - Automatic file type detection from GitHub Linguist's `languages.yml` via `go generate`
 - ~90 known filenames auto-detected (`.babelrc`, `tsconfig.json`, `Pipfile`, `pom.xml`, `.gitconfig`, etc.)

README.md

@@ -41,7 +41,7 @@
 Config File Validator is a cross-platform CLI tool that validates configuration files in your project. Catch syntax errors, schema violations, and misconfigurations across all your config files — with one tool.
 
 - **Single binary, zero dependencies** — no runtimes, no package managers, just one executable
-- **15 file formats** — JSON, JSONC, YAML, TOML, XML, HCL, INI, HOCON, ENV, CSV, Properties, EDITORCONFIG, PList, SARIF, and TOON
+- **16 file formats** — JSON, JSONC, YAML, TOML, XML, HCL, INI, HOCON, ENV, CSV, Properties, EDITORCONFIG, Justfile, PList, SARIF, and TOON
 - **Syntax + schema validation** — validates structure with [JSON Schema](https://json-schema.org/) and XSD, with automatic [SchemaStore](https://www.schemastore.org/) integration
 - **CI/CD ready** — JSON, JUnit, and SARIF output for GitHub Actions, GitLab CI, Jenkins, and more
 - **Configurable** — project-level `.cfv.toml` config files, glob patterns, schema mappings, and environment variables
@@ -74,6 +74,7 @@ Config File Validator is a cross-platform CLI tool that validates configuration
 | HCL | ✅ | ❌ |
 | HOCON | ✅ | ❌ |
 | INI | ✅ | ❌ |
+| Justfile | ✅ | ❌ |
 | JSON | ✅ | ✅ |
 | JSONC | ✅ | ✅ |
 | Properties | ✅ | ❌ |

cmd/validator/testdata/justfile.txtar

@@ -0,0 +1,20 @@
+# Justfile syntax validation
+! exec validator project
+stdout '✓.*valid.just'
+stdout '×.*invalid.just'
+
+# Known filenames detected without extension
+exec validator knownfile
+stdout '✓.*justfile'
+
+-- project/valid.just --
+default:
+    echo "hello"
+
+build:
+    echo "building"
+-- project/invalid.just --
+this is not valid {{{
+-- knownfile/justfile --
+greet name:
+    echo "hi {{name}}"

go.mod

@@ -26,6 +26,7 @@ require (
 )
 
 require (
+	github.com/Boeing/go-just v0.0.0
 	github.com/agext/levenshtein v1.2.1 // indirect
 	github.com/apparentlymart/go-textseg/v13 v13.0.0 // indirect
 	github.com/apparentlymart/go-textseg/v15 v15.0.0 // indirect
@@ -50,3 +51,5 @@ require (
 	golang.org/x/tools v0.43.0 // indirect
 	gopkg.in/warnings.v0 v0.1.2 // indirect
 )
+
+replace github.com/Boeing/go-just => ./pkg/validator/justfile

index.md

@@ -41,7 +41,7 @@ canonical_url: https://boeing.github.io/config-file-validator/
 Config File Validator is a cross-platform CLI tool that validates configuration files in your project. Catch syntax errors, schema violations, and misconfigurations across all your config files — with one tool.
 
 - **Single binary, zero dependencies** — no runtimes, no package managers, just one executable
-- **15 file formats** — JSON, JSONC, YAML, TOML, XML, HCL, INI, HOCON, ENV, CSV, Properties, EDITORCONFIG, PList, SARIF, and TOON
+- **16 file formats** — JSON, JSONC, YAML, TOML, XML, HCL, INI, HOCON, ENV, CSV, Properties, EDITORCONFIG, Justfile, PList, SARIF, and TOON
 - **Syntax + schema validation** — validates structure with [JSON Schema](https://json-schema.org/) and XSD, with automatic [SchemaStore](https://www.schemastore.org/) integration
 - **CI/CD ready** — JSON, JUnit, and SARIF output for GitHub Actions, GitLab CI, Jenkins, and more
 - **Configurable** — project-level `.cfv.toml` config files, glob patterns, schema mappings, and environment variables
@@ -74,6 +74,7 @@ Config File Validator is a cross-platform CLI tool that validates configuration
 | HCL | ✅ | ❌ |
 | HOCON | ✅ | ❌ |
 | INI | ✅ | ❌ |
+| Justfile | ✅ | ❌ |
 | JSON | ✅ | ✅ |
 | JSONC | ✅ | ✅ |
 | Properties | ✅ | ❌ |

pkg/filetype/file_type.go

@@ -147,11 +147,22 @@ var JSONCFileType = FileType{
 	Validator:  validator.JSONCValidator{},
 }
 
+var JustfileFileType = FileType{
+	Name:       "justfile",
+	Extensions: arrToMap("just"),
+	Validator:  validator.JustfileValidator{},
+}
+
 // extraKnownFiles contains manual entries not covered by Linguist.
 var extraKnownFiles = map[string][]string{
 	"ini": {
 		".shellcheckrc",
 	},
+	"justfile": {
+		"justfile",
+		"Justfile",
+		".justfile",
+	},
 }
 
 // fileTypeRegistry maps file type names to their package-level variables.
@@ -170,6 +181,7 @@ var fileTypeRegistry = map[string]*FileType{
 	"env":        &EnvFileType,
 	"toon":       &ToonFileType,
 	"sarif":      &SarifFileType,
+	"justfile":   &JustfileFileType,
 }
 
 // excludeKnownFiles lists Linguist entries to skip because we have
@@ -240,6 +252,7 @@ func init() {
 		ToonFileType,
 		SarifFileType,
 		JSONCFileType,
+		JustfileFileType,
 	}
 }
 

pkg/validator/justfile.go

@@ -0,0 +1,39 @@
+package validator
+
+import (
+	"errors"
+
+	"github.com/Boeing/go-just"
+)
+
+type JustfileValidator struct{}
+
+var _ Validator = JustfileValidator{}
+
+func (JustfileValidator) ValidateSyntax(b []byte) (bool, error) {
+	jf, err := gojust.Parse(b)
+	if err != nil {
+		var pe *gojust.ParseError
+		if errors.As(err, &pe) {
+			return false, &ValidationError{
+				Err:    errors.New(pe.Message),
+				Line:   pe.Pos.Line,
+				Column: pe.Pos.Column,
+			}
+		}
+		return false, err
+	}
+
+	diags := jf.Validate()
+	for _, d := range diags {
+		if d.Severity == gojust.SeverityError {
+			return false, &ValidationError{
+				Err:    errors.New(d.Message),
+				Line:   d.Pos.Line,
+				Column: d.Pos.Column,
+			}
+		}
+	}
+
+	return true, nil
+}

pkg/validator/justfile/.golangci.yml

@@ -0,0 +1,7 @@
+version: "2"
+
+linters:
+  settings:
+    gosec:
+      excludes:
+        - G101