Fix initialization of the logger (#1750)

* Fix initialization of the logger when `--log-level` is specified. Throw exception when an invalid value is passed.

Closes #1749

CHANGELOG.md

@@ -13,6 +13,7 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 * An enumeration class having a primary constructor and in which the list of enum entries is followed by a semicolon then do not remove the semicolon in case it is followed by code element `no-semi` ([#1733](https://github.com/pinterest/ktlint/issues/1733))
 * Add API so that KtLint API consumer is able to process a Kotlin script snippet without having to specify a file path ([#1738](https://github.com/pinterest/ktlint/issues/1738))
 * Disable the `standard:filename` rule whenever Ktlint CLI is run with option `--stdin` ([#1742](https://github.com/pinterest/ktlint/issues/1742))
+* Fix initialization of the logger when `--log-level` is specified. Throw exception when an invalid value is passed. ([#1749](https://github.com/pinterest/ktlint/issues/1749))
 
 ### Changed
 

ktlint/src/main/kotlin/com/pinterest/ktlint/Main.kt

@@ -21,6 +21,10 @@ public fun main(args: Array<String>) {
         .setUsageHelpAutoWidth(true)
     val parseResult = commandLine.parseArgs(*args)
 
+    // The logger needs to be configured for the ktlintCommand and all subcommands. The logger can however not be configured before the
+    // commandline has been parsed as otherwise the loglevel conversion is not yet executed.
+    ktlintCommand.configureLogger()
+
     commandLine.printCommandLineHelpOrVersionUsage()
 
     if (parseResult.hasSubcommand()) {

ktlint/src/main/kotlin/com/pinterest/ktlint/internal/KtlintCommandLine.kt

@@ -272,23 +272,17 @@ internal class KtlintCommandLine {
             .map { ruleId -> createRuleExecutionEditorConfigProperty(ruleId) to RuleExecution.disabled }
             .toTypedArray()
 
-    init {
+    fun run() {
         if (debugOld != null || trace != null || verbose != null) {
             if (minLogLevel == Level.OFF) {
                 minLogLevel = Level.ERROR
             }
-            configureLogger().error {
+            logger.error {
                 "Options '--debug', '--trace', '--verbose' and '-v' are deprecated and replaced with option '--log-level=<level>' or '-l=<level>'."
             }
             exitKtLintProcess(1)
         }
 
-        // Ensure that logger is initialized even when the run method is not executed because a subcommand like (--help)
-        // is executed so that method exitKtLintProcess only prints a log line when the appropriate loglevel is set.
-        logger = configureLogger()
-    }
-
-    fun run() {
         assertStdinAndPatternsFromStdinOptionsMutuallyExclusive()
 
         val stdinPatterns: Set<String> = readPatternsFromStdin()
@@ -368,13 +362,14 @@ internal class KtlintCommandLine {
             jarFile.toURI().toURL()
         }
 
-    private fun configureLogger() =
-        KotlinLogging
+    internal fun configureLogger() {
+        logger = KotlinLogging
             .logger {}
             .setDefaultLoggerModifier { logger ->
                 (logger.underlyingLogger as Logger).level = minLogLevel
             }
             .initKtLintKLogger()
+    }
 
     private fun assertStdinAndPatternsFromStdinOptionsMutuallyExclusive() {
         if (stdin && stdinDelimiter != null) {
@@ -721,7 +716,7 @@ private class LogLevelConverter : CommandLine.ITypeConverter<Level> {
             "WARN" -> Level.WARN
             "ERROR" -> Level.ERROR
             "NONE" -> Level.OFF
-            else -> Level.INFO
+            else -> throw IllegalStateException("Invalid log level '$value'")
         }
 }