refactor: ♻️ address several minor potential lint errors (#48)

* refactor: ♻️ address several minor potential lit errors

* disable MD013 for code

README.md

@@ -18,7 +18,7 @@
 
 ## Example
 
-<!-- markdownlint-disable MD010 -->
+<!-- markdownlint-disable MD010 MD013 -->
 
 ```go
 type config struct {
@@ -47,22 +47,20 @@ _ = os.Setenv("MY_DURATION_VALUE", "1h")
 
 err := y.Parse(args)
 if err != nil {
-	os.Exit(2)
+	fmt.Printf("Error: %v\n", err)
+	return
 }
 
-fmt.Printf("config.Str: %v\n", cfg.Str)
-fmt.Printf("config.Int: %v\n", cfg.Int)
-fmt.Printf("config.Bool %v\n", cfg.Bool)
-fmt.Printf("config.Duration: %v\n", cfg.Duration)
+fmt.Printf("config.Str: %v, ", cfg.Str)
+fmt.Printf("config.Int: %v, ", cfg.Int)
+fmt.Printf("config.Bool: %v, ", cfg.Bool)
+fmt.Printf("config.Duration: %v", cfg.Duration)
 
 // Output:
-// config.Str: str flag value
-// config.Int: 4
-// config.Bool: false
-// config.Duration: 1h0m0s
+// config.Str: str flag value, config.Int: 4, config.Bool: false, config.Duration: 1h0m0s
 ```
 
-<!-- markdownlint-enable MD010 -->
+<!-- markdownlint-enable MD010 MD013 -->
 
 ## Supported types
 

example_test.go

@@ -35,19 +35,15 @@ func Example() {
 
 	err := y.Parse(args)
 	if err != nil {
-		os.Exit(2)
+		fmt.Printf("Error: %v\n", err)
+		return
 	}
 
-	fmt.Printf("config.Str: %v\n", cfg.Str)
-	fmt.Printf("config.Int: %v\n", cfg.Int)
-	fmt.Printf("config.Bool %v\n", cfg.Bool)
-	fmt.Printf("config.Duration: %v\n", cfg.Duration)
+	fmt.Printf("config.Str: %v, ", cfg.Str)
+	fmt.Printf("config.Int: %v, ", cfg.Int)
+	fmt.Printf("config.Bool: %v, ", cfg.Bool)
+	fmt.Printf("config.Duration: %v", cfg.Duration)
 
 	// Output:
-	// config.Str: str flag value
-	// config.Int: 4
-	// config.Bool: false
-	// config.Duration: 1h0m0s
-
-	//
+	// config.Str: str flag value, config.Int: 4, config.Bool: false, config.Duration: 1h0m0s
 }

options_example_test.go

@@ -24,7 +24,8 @@ func ExampleWithEnvPrefix() {
 
 	err := y.Parse([]string{})
 	if err != nil {
-		os.Exit(2)
+		fmt.Printf("Error: %v\n", err)
+		return
 	}
 
 	fmt.Printf(cfg.Foo)
@@ -49,7 +50,8 @@ func ExampleFromEnv() {
 
 	err := y.Parse([]string{})
 	if err != nil {
-		os.Exit(2)
+		fmt.Printf("Error: %v\n", err)
+		return
 	}
 
 	fmt.Printf(cfg.Foo)
@@ -90,7 +92,8 @@ func ExampleRequired_flagOk() {
 
 	err := y.Parse([]string{"-foo=foo_value"})
 	if err != nil {
-		os.Exit(2)
+		fmt.Printf("Error: %v\n", err)
+		return
 	}
 
 	fmt.Print(cfg.Foo)
@@ -114,7 +117,8 @@ func ExampleRequired_envOnlyOk() {
 
 	err := y.Parse([]string{})
 	if err != nil {
-		os.Exit(2)
+		fmt.Printf("Error: %v\n", err)
+		return
 	}
 
 	fmt.Print(cfg.Foo)
@@ -158,7 +162,8 @@ func ExampleNoEnv() {
 	_ = os.Setenv("FOO", "Foo from the environment variable ")
 	err := y.Parse([]string{})
 	if err != nil {
-		os.Exit(2)
+		fmt.Printf("Error: %v\n", err)
+		return
 	}
 
 	fmt.Printf(cfg.Foo)

parser_test.go

@@ -7,7 +7,7 @@ import (
 	"github.com/zoido/yag-config"
 )
 
-func TestNew_Ok(t *testing.T) {
+func TestNew_Ok(_ *testing.T) {
 	// When
 	yag.New()
 

parser_types_test.go

@@ -267,12 +267,12 @@ type testFlagValue struct {
 	called bool
 }
 
-func (tfv *testFlagValue) Set(val string) error {
+func (tfv *testFlagValue) Set(_ string) error {
 	tfv.called = true
 	return nil
 }
 
-func (tfv *testFlagValue) String() string {
+func (*testFlagValue) String() string {
 	return "test_flag_value"
 }
 

value/bool.go

@@ -13,7 +13,7 @@ func Bool(dest *bool) flag.Value {
 // IsBoolFlag returns true if the flag.Value implementation has an IsBoolFlag() bool
 // method returning true.
 // This is used by the flag package commandline-parser for flags that can be supplied
-//  without "=value" text
+// without "=value" text.
 func IsBoolFlag(v flag.Value) bool {
 	type boolFlag interface {
 		flag.Value

value/bool_test.go

@@ -74,7 +74,7 @@ func TestIsBooleanFlag_BoolFlagTrue(t *testing.T) {
 
 type normalFlagValue struct{}
 
-func (*normalFlagValue) Set(v string) error {
+func (*normalFlagValue) Set(_ string) error {
 	return nil
 }