fix gradle 7 compatibility

CHANGELOG.md

@@ -1,3 +1,5 @@
+* Fix gradle 7 compatibility (for checkstyle plugin)
+
 ### 4.5.0 (2021-02-06)
 * Fix report separating lines disappear in intellij IDEA output (appears when gradle output recognized as junit test output).
   Extra zero-width space symbol used to prevent trims.

src/main/groovy/ru/vyarus/gradle/plugin/quality/ConfigLoader.groovy

@@ -37,7 +37,11 @@ class ConfigLoader {
 
     File resolveCheckstyleConfigDir() {
         // used for ${config_loc} property definition (through checkstyle.configDirectory property)
-        return new File(configDir, checkstyle).parentFile
+        File path = new File(configDir, checkstyle).parentFile
+        // if custom directory exists, use it, otherwise fall back to generated directory
+        // because gradle 7 requires configured directory existence
+        // (default file copying forced to create checkstyle directory and avoid gradle complains)
+        return path.exists() ? path : resolveCheckstyleConfig(true).parentFile
     }
 
     File resolvePmdConfig(boolean copyDefaultFile = true) {

src/test/groovy/ru/vyarus/gradle/plugin/quality/BuildCacheSupportKitTest.groovy

@@ -142,9 +142,11 @@ class BuildCacheSupportKitTest extends AbstractKitTest {
         result = run('clean', 'check', '--build-cache')
 
         then: "all plugins detect violations"
-        result.task(":check").outcome == TaskOutcome.UP_TO_DATE
+        result.task(":check").outcome == TaskOutcome.SUCCESS
         result.task(":codenarcMain").outcome == TaskOutcome.FROM_CACHE
-        result.task(":checkstyleMain").outcome == TaskOutcome.FROM_CACHE
+        // since gradle 7 checkstyle's config dir must point to existing directory and so
+        // after project move directory (configDirectory) would always change and cache would miss
+        result.task(":checkstyleMain").outcome == TaskOutcome.SUCCESS
         result.task(":spotbugsMain").outcome == TaskOutcome.FROM_CACHE
         result.task(":pmdMain").outcome == TaskOutcome.FROM_CACHE
         result.output.contains('CodeNarc violations were found in 2 files')

src/test/groovy/ru/vyarus/gradle/plugin/quality/UpstreamKitTest.groovy

@@ -12,7 +12,7 @@ import org.gradle.testkit.runner.TaskOutcome
 class UpstreamKitTest extends AbstractKitTest {
 
 
-    public static final String GRADLE = '6.8.1'
+    public static final String GRADLE = '7.0'
 
     def "Check java checks"() {
         setup: