Allow plugins to contribute to the default configuration

detekt-cli/src/main/kotlin/io/gitlab/arturbosch/detekt/cli/CliRunner.kt

@@ -20,7 +20,7 @@ class CliRunner : DetektCli {
 
         val specialRunner = when {
             arguments.showVersion -> VersionPrinter(outputChannel)
-            arguments.generateConfig -> ConfigExporter(arguments, outputChannel)
+            arguments.generateConfig -> ConfigExporter(arguments, outputChannel, errorChannel)
             arguments.printAst -> AstPrinter(arguments, outputChannel)
             else -> null
         }

detekt-cli/src/main/kotlin/io/gitlab/arturbosch/detekt/cli/Main.kt

@@ -54,7 +54,7 @@ fun buildRunner(
     val arguments = parseArguments(args)
     return when {
         arguments.showVersion -> VersionPrinter(outputPrinter)
-        arguments.generateConfig -> ConfigExporter(arguments, outputPrinter)
+        arguments.generateConfig -> ConfigExporter(arguments, outputPrinter, errorPrinter)
         arguments.printAst -> AstPrinter(arguments, outputPrinter)
         else -> Runner(arguments, outputPrinter, errorPrinter)
     }

detekt-cli/src/main/kotlin/io/gitlab/arturbosch/detekt/cli/runners/ConfigExporter.kt

@@ -2,16 +2,19 @@ package io.gitlab.arturbosch.detekt.cli.runners
 
 import io.github.detekt.tooling.api.DefaultConfigurationProvider
 import io.gitlab.arturbosch.detekt.cli.CliArgs
+import io.gitlab.arturbosch.detekt.cli.createSpec
 import java.nio.file.Paths
 
 class ConfigExporter(
     private val arguments: CliArgs,
-    private val outputPrinter: Appendable
+    private val outputPrinter: Appendable,
+    private val errorPrinter: Appendable,
 ) : Executable {
 
     override fun execute() {
         val configPath = Paths.get(arguments.config ?: "detekt.yml")
-        DefaultConfigurationProvider.load().copy(configPath)
+        val spec = arguments.createSpec(outputPrinter, errorPrinter)
+        DefaultConfigurationProvider.load(spec).copy(configPath)
         outputPrinter.appendLine("Successfully copied default config to ${configPath.toAbsolutePath()}")
     }
 }

detekt-cli/src/test/kotlin/io/gitlab/arturbosch/detekt/cli/runners/ConfigExporterSpec.kt

@@ -16,7 +16,7 @@ class ConfigExporterSpec : Spek({
             val tmpConfig = createTempFileForTest("ConfigPrinterSpec", ".yml")
             val cliArgs = parseArguments(arrayOf("--config", tmpConfig.toString()))
 
-            ConfigExporter(cliArgs, NullPrintStream()).execute()
+            ConfigExporter(cliArgs, NullPrintStream(), NullPrintStream()).execute()
 
             assertThat(Files.readAllLines(tmpConfig)).isNotEmpty
         }

detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/Analyzer.kt

@@ -15,12 +15,12 @@ import io.gitlab.arturbosch.detekt.api.internal.whichDetekt
 import io.gitlab.arturbosch.detekt.api.internal.whichJava
 import io.gitlab.arturbosch.detekt.api.internal.whichOS
 import io.gitlab.arturbosch.detekt.core.config.AllRulesConfig
-import io.gitlab.arturbosch.detekt.core.config.DefaultConfig
 import io.gitlab.arturbosch.detekt.core.config.DisabledAutoCorrectConfig
 import io.gitlab.arturbosch.detekt.core.rules.associateRuleIdsToRuleSetIds
 import io.gitlab.arturbosch.detekt.core.rules.isActive
 import io.gitlab.arturbosch.detekt.core.rules.shouldAnalyzeFile
 import io.gitlab.arturbosch.detekt.core.suppressors.getSuppressors
+import io.gitlab.arturbosch.detekt.core.tooling.getDefaultConfiguration
 import org.jetbrains.kotlin.config.languageVersionSettings
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.resolve.BindingContext
@@ -171,13 +171,13 @@ internal fun ProcessingSpec.workaroundConfiguration(config: Config): Config = wi
     }
 
     if (rulesSpec.activateAllRules) {
-        val defaultConfig = DefaultConfig.newInstance()
+        val defaultConfig = getDefaultConfiguration()
         declaredConfig = AllRulesConfig(declaredConfig ?: defaultConfig, defaultConfig)
     }
 
     if (!rulesSpec.autoCorrect) {
-        declaredConfig = DisabledAutoCorrectConfig(declaredConfig ?: DefaultConfig.newInstance())
+        declaredConfig = DisabledAutoCorrectConfig(declaredConfig ?: getDefaultConfiguration())
     }
 
-    return declaredConfig ?: DefaultConfig.newInstance()
+    return declaredConfig ?: getDefaultConfiguration()
 }

detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/config/ConfigValidators.kt

@@ -1,6 +1,7 @@
 package io.gitlab.arturbosch.detekt.core.config
 
 import io.github.detekt.tooling.api.InvalidConfig
+import io.gitlab.arturbosch.detekt.api.Config
 import io.gitlab.arturbosch.detekt.api.ConfigValidator
 import io.gitlab.arturbosch.detekt.api.Notification
 import io.gitlab.arturbosch.detekt.core.NL
@@ -9,12 +10,13 @@ import io.gitlab.arturbosch.detekt.core.extensions.loadExtensions
 import io.gitlab.arturbosch.detekt.core.reporting.red
 import io.gitlab.arturbosch.detekt.core.reporting.yellow
 
-internal fun checkConfiguration(settings: ProcessingSettings) {
+internal fun checkConfiguration(settings: ProcessingSettings, baseline: Config) {
     val props = settings.config.subConfig("config")
     val shouldValidate = props.valueOrDefault("validation", true)
 
     if (shouldValidate) {
-        val validators = loadExtensions<ConfigValidator>(settings) + DefaultPropertiesConfigValidator(settings)
+        val validators =
+            loadExtensions<ConfigValidator>(settings) + DefaultPropertiesConfigValidator(settings, baseline)
         val notifications = validators.flatMap { it.validate(settings.config) }
         notifications.map(Notification::message).forEach(settings::info)
         val errors = notifications.filter(Notification::isError)

detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/config/Configurations.kt

@@ -4,6 +4,7 @@ import io.github.detekt.tooling.api.spec.ConfigSpec
 import io.github.detekt.tooling.api.spec.ProcessingSpec
 import io.github.detekt.utils.openSafeStream
 import io.gitlab.arturbosch.detekt.api.Config
+import io.gitlab.arturbosch.detekt.core.tooling.getDefaultConfiguration
 import java.net.URI
 import java.net.URL
 import java.nio.file.FileSystemNotFoundException
@@ -19,13 +20,13 @@ internal fun ProcessingSpec.loadConfiguration(): Config = with(configSpec) {
 
     if (useDefaultConfig) {
         declaredConfig = if (declaredConfig == null) {
-            DefaultConfig.newInstance()
+            getDefaultConfiguration()
         } else {
-            CompositeConfig(declaredConfig, DefaultConfig.newInstance())
+            CompositeConfig(declaredConfig, getDefaultConfiguration())
         }
     }
 
-    return declaredConfig ?: DefaultConfig.newInstance()
+    return declaredConfig ?: getDefaultConfiguration()
 }
 
 private fun parseResourceConfig(urls: Collection<URL>): Config =

detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/config/DefaultPropertiesConfigValidator.kt

@@ -9,7 +9,8 @@ import io.gitlab.arturbosch.detekt.core.ProcessingSettings
 import io.gitlab.arturbosch.detekt.core.rules.RuleSetLocator
 
 class DefaultPropertiesConfigValidator(
-    private val settings: ProcessingSettings
+    private val settings: ProcessingSettings,
+    private val baseline: Config,
 ) : ConfigValidator {
 
     override fun validate(config: Config): Collection<Notification> {
@@ -21,6 +22,6 @@ class DefaultPropertiesConfigValidator(
             val allExcludes = "$configExcludes,$DEFAULT_PROPERTY_EXCLUDES,$pluginExcludes"
             return CommaSeparatedPattern(allExcludes).mapToRegex()
         }
-        return validateConfig(config, DefaultConfig.newInstance(), patterns())
+        return validateConfig(config, baseline, patterns())
     }
 }

detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/tooling/AnalysisFacade.kt

@@ -22,17 +22,22 @@ class AnalysisFacade(
     private val spec: ProcessingSpec
 ) : Detekt {
 
-    override fun run(): AnalysisResult = runAnalysis { DefaultLifecycle(it, inputPathsToKtFiles) }
+    override fun run(): AnalysisResult = runAnalysis {
+        DefaultLifecycle(spec.getDefaultConfiguration(), it, inputPathsToKtFiles)
+    }
 
     override fun run(path: Path): AnalysisResult =
-        runAnalysis { DefaultLifecycle(it, pathToKtFile(path)) }
+        runAnalysis { DefaultLifecycle(spec.getDefaultConfiguration(), it, pathToKtFile(path)) }
 
     override fun run(sourceCode: String, filename: String): AnalysisResult =
-        runAnalysis { DefaultLifecycle(it, contentToKtFile(sourceCode, Paths.get(filename))) }
+        runAnalysis {
+            DefaultLifecycle(spec.getDefaultConfiguration(), it, contentToKtFile(sourceCode, Paths.get(filename)))
+        }
 
     override fun run(files: Collection<KtFile>, bindingContext: BindingContext): AnalysisResult =
         runAnalysis {
             DefaultLifecycle(
+                spec.getDefaultConfiguration(),
                 it,
                 parsingStrategy = { files.toList() },
                 bindingProvider = { bindingContext }

detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/tooling/DefaultConfigProvider.kt

@@ -1,19 +1,55 @@
 package io.gitlab.arturbosch.detekt.core.tooling
 
 import io.github.detekt.tooling.api.DefaultConfigurationProvider
+import io.github.detekt.tooling.api.spec.ProcessingSpec
+import io.github.detekt.utils.getSafeResourceAsStream
 import io.github.detekt.utils.openSafeStream
 import io.gitlab.arturbosch.detekt.api.Config
-import io.gitlab.arturbosch.detekt.core.config.DefaultConfig
+import io.gitlab.arturbosch.detekt.core.config.YamlConfig
+import io.gitlab.arturbosch.detekt.core.settings.ExtensionFacade
+import java.io.ByteArrayInputStream
+import java.io.ByteArrayOutputStream
+import java.io.InputStream
 import java.nio.file.Files
 import java.nio.file.Path
 import java.nio.file.StandardCopyOption
 
 class DefaultConfigProvider : DefaultConfigurationProvider {
+    private lateinit var spec: ProcessingSpec
 
-    override fun get(): Config = DefaultConfig.newInstance()
+    override fun init(spec: ProcessingSpec) {
+        this.spec = spec
+    }
+
+    override fun get(): Config = spec.getDefaultConfiguration()
 
     override fun copy(targetLocation: Path) {
-        val configUrl = javaClass.getResource("/${DefaultConfig.RESOURCE_NAME}")!!
-        Files.copy(configUrl.openSafeStream(), targetLocation, StandardCopyOption.REPLACE_EXISTING)
+        Files.copy(configInputStream(spec), targetLocation, StandardCopyOption.REPLACE_EXISTING)
     }
 }
+
+private fun configInputStream(spec: ProcessingSpec): InputStream {
+    val outputStream = ByteArrayOutputStream()
+
+    requireNotNull(spec.javaClass.getSafeResourceAsStream("/default-detekt-config.yml"))
+        .use { it.copyTo(outputStream) }
+
+    ExtensionFacade(spec.extensionsSpec).pluginLoader
+        .getResourcesAsStream("config/config.yml")
+        .forEach { inputStream ->
+            outputStream.bufferedWriter().append('\n').flush()
+            inputStream.use { it.copyTo(outputStream) }
+        }
+
+    return ByteArrayInputStream(outputStream.toByteArray())
+}
+
+private fun ClassLoader.getResourcesAsStream(name: String): Sequence<InputStream> {
+    return getResources(name)
+        .asSequence()
+        .map { it.openSafeStream() }
+}
+
+fun ProcessingSpec.getDefaultConfiguration(): Config {
+    return YamlConfig.load(configInputStream(this).reader())
+}

detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/tooling/Lifecycle.kt

@@ -1,5 +1,6 @@
 package io.gitlab.arturbosch.detekt.core.tooling
 
+import io.gitlab.arturbosch.detekt.api.Config
 import io.gitlab.arturbosch.detekt.api.Detektion
 import io.gitlab.arturbosch.detekt.api.FileProcessListener
 import io.gitlab.arturbosch.detekt.api.Finding
@@ -22,6 +23,7 @@ import org.jetbrains.kotlin.resolve.BindingContext
 
 internal interface Lifecycle {
 
+    val baselineConfig: Config
     val settings: ProcessingSettings
     val parsingStrategy: ParsingStrategy
     val bindingProvider: (files: List<KtFile>) -> BindingContext
@@ -32,7 +34,7 @@ internal interface Lifecycle {
     private fun <R> measure(phase: Phase, block: () -> R): R = settings.getOrCreateMonitor().measure(phase, block)
 
     fun analyze(): Detektion {
-        measure(Phase.ValidateConfig) { checkConfiguration(settings) }
+        measure(Phase.ValidateConfig) { checkConfiguration(settings, baselineConfig) }
         val filesToAnalyze = measure(Phase.Parsing) { parsingStrategy.invoke(settings) }
         val bindingContext = measure(Phase.Binding) { bindingProvider.invoke(filesToAnalyze) }
         val (processors, ruleSets) = measure(Phase.LoadingExtensions) {
@@ -57,6 +59,7 @@ internal interface Lifecycle {
 }
 
 internal class DefaultLifecycle(
+    override val baselineConfig: Config,
     override val settings: ProcessingSettings,
     override val parsingStrategy: ParsingStrategy,
     override val bindingProvider: (files: List<KtFile>) -> BindingContext =

detekt-core/src/test/kotlin/io/gitlab/arturbosch/detekt/core/TopLevelAutoCorrectSpec.kt

@@ -17,6 +17,7 @@ import io.gitlab.arturbosch.detekt.api.Severity
 import io.gitlab.arturbosch.detekt.core.tooling.AnalysisFacade
 import io.gitlab.arturbosch.detekt.core.tooling.DefaultLifecycle
 import io.gitlab.arturbosch.detekt.core.tooling.inputPathsToKtFiles
+import io.mockk.mockk
 import org.assertj.core.api.Assertions.assertThat
 import org.jetbrains.kotlin.psi.KtAnnotation
 import org.jetbrains.kotlin.psi.KtFile
@@ -56,6 +57,7 @@ class TopLevelAutoCorrectSpec : Spek({
 
             AnalysisFacade(spec).runAnalysis {
                 DefaultLifecycle(
+                    mockk(),
                     it,
                     inputPathsToKtFiles,
                     processorsProvider = { listOf(contentChangedListener) },

detekt-core/src/test/kotlin/io/gitlab/arturbosch/detekt/core/config/CheckConfigurationSpec.kt

@@ -8,7 +8,9 @@ import io.gitlab.arturbosch.detekt.api.Notification
 import io.gitlab.arturbosch.detekt.api.RuleSet
 import io.gitlab.arturbosch.detekt.api.RuleSetProvider
 import io.gitlab.arturbosch.detekt.api.internal.SimpleNotification
+import io.gitlab.arturbosch.detekt.core.createNullLoggingSpec
 import io.gitlab.arturbosch.detekt.core.createProcessingSettings
+import io.gitlab.arturbosch.detekt.core.tooling.getDefaultConfiguration
 import io.gitlab.arturbosch.detekt.test.yamlConfigFromContent
 import org.assertj.core.api.Assertions.assertThatCode
 import org.spekframework.spek2.Spek
@@ -19,6 +21,7 @@ class SupportConfigValidationSpec : Spek({
     describe("support config validation") {
 
         val testDir by memoized { createTempDirectoryForTest("detekt-sample") }
+        val spec by memoized { createNullLoggingSpec {} }
 
         it("fails when unknown properties are found") {
             val config = yamlConfigFromContent(
@@ -35,7 +38,7 @@ class SupportConfigValidationSpec : Spek({
             """
             )
             createProcessingSettings(testDir, config).use {
-                assertThatCode { checkConfiguration(it) }
+                assertThatCode { checkConfiguration(it, spec.getDefaultConfiguration()) }
                     .isInstanceOf(InvalidConfig::class.java)
                     .hasMessageContaining("Run failed with 1 invalid config property.")
                     .hasMessageContaining("my_additional_properties")
@@ -53,7 +56,7 @@ class SupportConfigValidationSpec : Spek({
             """
             )
             createProcessingSettings(testDir, config).use {
-                assertThatCode { checkConfiguration(it) }
+                assertThatCode { checkConfiguration(it, spec.getDefaultConfiguration()) }
                     .isInstanceOf(InvalidConfig::class.java)
                     .hasMessageContaining("Run failed with 1 invalid config property.")
             }
@@ -82,7 +85,8 @@ class SupportConfigValidationSpec : Spek({
             """
             )
             createProcessingSettings(testDir, config).use {
-                assertThatCode { checkConfiguration(it) }.doesNotThrowAnyException()
+                assertThatCode { checkConfiguration(it, spec.getDefaultConfiguration()) }
+                    .doesNotThrowAnyException()
             }
         }
     }