Remove --loglevel CLI flag

README.md

@@ -129,7 +129,6 @@ Application Options:
       --force                                                   Return zero exit status even if issues found
       --color                                                   Enable colorized output
       --no-color                                                Disable colorized output
-      --loglevel=[trace|debug|info|warn|error]                  Change the loglevel
 
 Help Options:
   -h, --help                                                    Show this help message

cmd/cli.go

@@ -64,11 +64,6 @@ func (cli *CLI) Run(args []string) int {
 		cli.formatter.NoColor = true
 	}
 	level := os.Getenv("TFLINT_LOG")
-	if opts.LogLevel != "" {
-		level = opts.LogLevel
-		// Pass log level to plugin processes
-		os.Setenv("TFLINT_LOG", level)
-	}
 	log.SetOutput(&logutils.LevelFilter{
 		Levels:   []logutils.LogLevel{"TRACE", "DEBUG", "INFO", "WARN", "ERROR"},
 		MinLevel: logutils.LogLevel(strings.ToUpper(level)),
@@ -167,5 +162,8 @@ func unknownOptionHandler(option string, arg flags.SplitArgument, args []string)
 	if option == "aws-access-key" || option == "aws-secret-key" || option == "aws-profile" || option == "aws-creds-file" || option == "aws-region" {
 		return []string{}, fmt.Errorf("`%s` option was removed in v0.23.0. AWS rules are provided by the AWS plugin, so please configure the plugin instead", option)
 	}
+	if option == "loglevel" {
+		return []string{}, errors.New("`loglevel` option was removed in v0.40.0. Please set `TFLINT_LOG` environment variables instead")
+	}
 	return []string{}, fmt.Errorf("`%s` is unknown option. Please run `tflint --help`", option)
 }

cmd/cli_test.go

@@ -135,6 +135,12 @@ func TestCLIRun__noIssuesFound(t *testing.T) {
 			Status:  ExitCodeError,
 			Stderr:  "`aws-region` option was removed in v0.23.0. AWS rules are provided by the AWS plugin, so please configure the plugin instead",
 		},
+		{
+			Name:    "removed `loglevel` options",
+			Command: "./tflint --loglevel debug",
+			Status:  ExitCodeError,
+			Stderr:  "`loglevel` option was removed in v0.40.0. Please set `TFLINT_LOG` environment variables instead",
+		},
 		{
 			Name:    "invalid options",
 			Command: "./tflint --unknown",

cmd/option.go

@@ -25,7 +25,6 @@ type Options struct {
 	Force         bool     `long:"force" description:"Return zero exit status even if issues found"`
 	Color         bool     `long:"color" description:"Enable colorized output"`
 	NoColor       bool     `long:"no-color" description:"Disable colorized output"`
-	LogLevel      string   `long:"loglevel" description:"Change the loglevel" choice:"trace" choice:"debug" choice:"info" choice:"warn" choice:"error"`
 }
 
 func (opts *Options) toConfig() *tflint.Config {