test: add tests for Options (#19)

sloglint.go

@@ -39,19 +39,22 @@ func New(opts *Options) *analysis.Analyzer {
 		Requires: []*analysis.Analyzer{inspect.Analyzer},
 		Run: func(pass *analysis.Pass) (any, error) {
 			if opts.KVOnly && opts.AttrOnly {
-				return nil, errors.New("sloglint: incompatible options provided")
+				return nil, fmt.Errorf("sloglint: Options.KVOnly and Options.AttrOnly: %w", errIncompatible)
+			}
+			switch opts.KeyNamingCase {
+			case "", snakeCase, kebabCase, camelCase, pascalCase:
+			default:
+				return nil, fmt.Errorf("sloglint: Options.KeyNamingCase=%s: %w", opts.KeyNamingCase, errInvalidValue)
 			}
 			run(pass, opts)
 			return nil, nil
 		},
 	}
 }
 
-const (
-	snakeCase  = "snake"
-	kebabCase  = "kebab"
-	camelCase  = "camel"
-	pascalCase = "pascal"
+var (
+	errIncompatible = errors.New("incompatible options")
+	errInvalidValue = errors.New("invalid value")
 )
 
 func flags(opts *Options) flag.FlagSet {
@@ -72,13 +75,8 @@ func flags(opts *Options) flag.FlagSet {
 	boolVar(&opts.ArgsOnSepLines, "args-on-sep-lines", "enforce putting arguments on separate lines")
 
 	fs.Func("key-naming-case", "enforce a single key naming convention (snake|kebab|camel|pascal)", func(s string) error {
-		switch s {
-		case snakeCase, kebabCase, camelCase, pascalCase:
-			opts.KeyNamingCase = s
-			return nil
-		default:
-			return fmt.Errorf("sloglint: -key-naming-case=%s: invalid value", s)
-		}
+		opts.KeyNamingCase = s
+		return nil
 	})
 
 	return *fs
@@ -118,6 +116,13 @@ var attrFuncs = map[string]struct{}{
 	"log/slog.Any":      {},
 }
 
+const (
+	snakeCase  = "snake"
+	kebabCase  = "kebab"
+	camelCase  = "camel"
+	pascalCase = "pascal"
+)
+
 func run(pass *analysis.Pass, opts *Options) {
 	visit := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
 	filter := []ast.Node{(*ast.CallExpr)(nil)}

sloglint_internal_test.go

@@ -0,0 +1,31 @@
+package sloglint
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestOptions(t *testing.T) {
+	tests := map[string]struct {
+		opts Options
+		err  error
+	}{
+		"incompatible": {
+			opts: Options{KVOnly: true, AttrOnly: true},
+			err:  errIncompatible,
+		},
+		"invalid value": {
+			opts: Options{KeyNamingCase: "-"},
+			err:  errInvalidValue,
+		},
+	}
+
+	for name, test := range tests {
+		t.Run(name, func(t *testing.T) {
+			analyzer := New(&test.opts)
+			if _, err := analyzer.Run(nil); !errors.Is(err, test.err) {
+				t.Errorf("errors.Is() mismatch\ngot:  %v\nwant: %v", err, test.err)
+			}
+		})
+	}
+}