[Parameter Hints] IDEA-164121, clear state when empty element is passed

platform/lang-impl/src/com/intellij/codeInsight/hints/settings/ParameterNameHintsSettings.kt

@@ -80,11 +80,17 @@ class ParameterNameHintsSettings : PersistentStateComponent<Element> {
   }
 
   override fun loadState(state: Element) {
-    val allBlackLists = state.getChild(XmlTagHelper.BLACKLISTS)?.getChildren(XmlTagHelper.LANGUAGE_LIST) ?: emptyList()
-    allBlackLists.mapNotNull {
-      val language = it.attributeValue(XmlTagHelper.LANGUAGE) ?: return@mapNotNull
-      myAddedPatterns[language] = it.extractPatterns(XmlTagHelper.ADDED)
-      myRemovedPatterns[language] = it.extractPatterns(XmlTagHelper.REMOVED)
+    val allBlackLists = state
+      .getChild(XmlTagHelper.BLACKLISTS)
+      ?.getChildren(XmlTagHelper.LANGUAGE_LIST) ?: emptyList()
+
+    myAddedPatterns.clear()
+    myRemovedPatterns.clear()
+
+    allBlackLists.mapNotNull { blacklist ->
+      val language = blacklist.attributeValue(XmlTagHelper.LANGUAGE) ?: return@mapNotNull
+      myAddedPatterns[language] = blacklist.extractPatterns(XmlTagHelper.ADDED)
+      myRemovedPatterns[language] = blacklist.extractPatterns(XmlTagHelper.REMOVED)
     }
   }
   

platform/lang-impl/testSources/com/intellij/codeInsight/hints/settings/ParameterNameSettingsTest.kt

@@ -20,6 +20,7 @@ import com.intellij.codeInsight.hints.InlayParameterHintsProvider
 import com.intellij.openapi.fileTypes.PlainTextLanguage
 import com.intellij.psi.PsiElement
 import junit.framework.TestCase
+import org.jdom.Element
 
 
 class MockInlayProvider(override val defaultBlackList: Set<String>): InlayParameterHintsProvider {
@@ -75,6 +76,18 @@ class ParameterNameSettingsTest : TestCase() {
     assert(ignoreSet.contains("xxx"))
   }
 
+  fun `test if empty element is passed settings are dropped`() {
+    addIgnorePattern("new_ignore_pattern")
+
+    var ignoreSet = getIgnoreSet()
+    assert(ignoreSet.size == 1)
+
+    settings.loadState(Element("element"))
+
+    ignoreSet = getIgnoreSet()
+    assert(ignoreSet.isEmpty())
+  }
+
   fun `test removed pattern is removed when defaults are updated`() {
     defaultSettingsUpdated("aaa", "bbb")
 

plugins/groovy/test/org/jetbrains/plugins/groovy/codeInsight/hint/GroovyInlayParameterHintsProviderTest.groovy

@@ -19,7 +19,7 @@ import com.intellij.codeInsight.daemon.impl.ParameterHintsPresentationManager
 import com.intellij.codeInsight.hints.settings.ParameterNameHintsSettings
 import com.intellij.testFramework.LightProjectDescriptor
 import groovy.transform.CompileStatic
-import groovy.transform.TypeCheckingMode
+import org.jdom.Element
 import org.jetbrains.plugins.groovy.GroovyLightProjectDescriptor
 import org.jetbrains.plugins.groovy.LightGroovyTestCase
 
@@ -47,10 +47,8 @@ class Foo {
   }
 
   @Override
-  @CompileStatic(TypeCheckingMode.SKIP)
   void tearDown() throws Exception {
-    ParameterNameHintsSettings.getInstance().myAddedPatterns.clear()
-    ParameterNameHintsSettings.getInstance().myRemovedPatterns.clear()
+    ParameterNameHintsSettings.getInstance().loadState(new Element("element"))
     super.tearDown()
   }