Fixed bug with wrong completion in class declaration

idea/src/org/jetbrains/kotlin/idea/completion/KotlinCompletionContributor.kt

@@ -20,47 +20,30 @@ import com.intellij.codeInsight.completion.*
 import com.intellij.openapi.editor.Document
 import com.intellij.openapi.progress.ProcessCanceledException
 import com.intellij.patterns.PlatformPatterns
-import com.intellij.util.ProcessingContext
-import org.jetbrains.kotlin.psi.JetBlockExpression
-import org.jetbrains.kotlin.psi.JetCallExpression
-import org.jetbrains.kotlin.psi.JetExpression
-import org.jetbrains.kotlin.psi.JetFile
-import org.jetbrains.kotlin.lexer.JetTokens
-import org.jetbrains.kotlin.idea.completion.smart.SmartCompletion
-
 import com.intellij.patterns.PsiJavaPatterns.elementType
 import com.intellij.patterns.PsiJavaPatterns.psiElement
+import com.intellij.psi.PsiComment
 import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiErrorElement
+import com.intellij.psi.TokenType
+import com.intellij.psi.search.PsiElementProcessor
 import com.intellij.psi.tree.TokenSet
 import com.intellij.psi.util.PsiTreeUtil
-import com.intellij.psi.TokenType
+import com.intellij.util.ProcessingContext
-import org.jetbrains.kotlin.psi.JetNameReferenceExpression
-import org.jetbrains.kotlin.psi.JetUserType
-import org.jetbrains.kotlin.psi.JetTypeReference
-import org.jetbrains.kotlin.psi.JetNamedFunction
-import org.jetbrains.kotlin.psi.JetProperty
-import org.jetbrains.kotlin.psi.JetPsiFactory
-import com.intellij.psi.PsiErrorElement
-import com.intellij.psi.search.PsiElementProcessor
-import com.intellij.psi.PsiComment
-import org.jetbrains.kotlin.psi.psiUtil.parents
-import org.jetbrains.kotlin.psi.JetParameterList
-import org.jetbrains.kotlin.psi.JetFunctionLiteral
-import org.jetbrains.kotlin.psi.psiUtil.prevLeafSkipWhitespacesAndComments
-import org.jetbrains.kotlin.psi.JetValueArgument
-import org.jetbrains.kotlin.psi.JetValueArgumentList
-import org.jetbrains.kotlin.psi.psiUtil.getNonStrictParentOfType
-import org.jetbrains.kotlin.psi.psiUtil.prevLeaf
-import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
-import org.jetbrains.kotlin.psi.JetTypeArgumentList
-import org.jetbrains.kotlin.resolve.BindingContext
-import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.getResolutionFacade
+import org.jetbrains.kotlin.idea.completion.smart.SmartCompletion
+import org.jetbrains.kotlin.lexer.JetTokens
+import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.psiUtil.getNonStrictParentOfType
+import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
+import org.jetbrains.kotlin.psi.psiUtil.parents
+import org.jetbrains.kotlin.psi.psiUtil.prevLeaf
+import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
-import org.jetbrains.kotlin.psi.JetTypeElement
+import org.jetbrains.kotlin.utils.addToStdlib.firstIsInstanceOrNull
-import org.jetbrains.kotlin.psi.JetAnnotationEntry
 
 public class KotlinCompletionContributor : CompletionContributor() {
 
@@ -93,6 +76,8 @@ public class KotlinCompletionContributor : CompletionContributor() {
 
             isInFunctionLiteralParameterList(tokenBefore) -> CompletionUtilCore.DUMMY_IDENTIFIER_TRIMMED
 
+            isInClassHeader(tokenBefore) -> CompletionUtilCore.DUMMY_IDENTIFIER // do not add '$' to not interrupt class declaration parsing
+
             else -> specialExtensionReceiverDummyIdentifier(tokenBefore)
                     ?: specialInTypeArgsDummyIdentifier(tokenBefore)
                     ?: specialInParameterListDummyIdentifier(tokenBefore)
@@ -146,6 +131,14 @@ public class KotlinCompletionContributor : CompletionContributor() {
         return parent is JetFunctionLiteral && parent.getValueParameterList() == parameterList
     }
 
+    private fun isInClassHeader(tokenBefore: PsiElement?): Boolean {
+        val classOrObject = tokenBefore?.parents(false)?.firstIsInstanceOrNull<JetClassOrObject>() ?: return false
+        val name = classOrObject.getNameIdentifier() ?: return false
+        val body = classOrObject.getBody() ?: return false
+        val offset = tokenBefore!!.getTextRange().getStartOffset()
+        return name.getTextRange().getEndOffset() <= offset && offset <= body.getTextRange().getStartOffset()
+    }
+
     private val declarationKeywords = TokenSet.create(JetTokens.FUN_KEYWORD, JetTokens.VAL_KEYWORD, JetTokens.VAR_KEYWORD)
     private val declarationTokens = TokenSet.orSet(TokenSet.create(JetTokens.IDENTIFIER, JetTokens.LT, JetTokens.GT,
                                                                    JetTokens.COMMA, JetTokens.DOT, JetTokens.QUEST, JetTokens.COLON,

idea/testData/completion/basic/common/NestedClassBug.kt

@@ -0,0 +1,7 @@
+package ppp
+
+class Base(p: Base.N<caret>) {
+    class Nested
+}
+
+// EXIST: { lookupString: "Nested", itemText: "Nested", tailText: " (ppp.Base)" }

idea/tests/org/jetbrains/kotlin/completion/JSBasicCompletionTestGenerated.java

@@ -601,6 +601,12 @@ public class JSBasicCompletionTestGenerated extends AbstractJSBasicCompletionTes
             doTest(fileName);
         }
 
+        @TestMetadata("NestedClassBug.kt")
+        public void testNestedClassBug() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/basic/common/NestedClassBug.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("NestedClassNameForExtension.kt")
         public void testNestedClassNameForExtension() throws Exception {
             String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/basic/common/NestedClassNameForExtension.kt");

idea/tests/org/jetbrains/kotlin/completion/JvmBasicCompletionTestGenerated.java

@@ -601,6 +601,12 @@ public class JvmBasicCompletionTestGenerated extends AbstractJvmBasicCompletionT
             doTest(fileName);
         }
 
+        @TestMetadata("NestedClassBug.kt")
+        public void testNestedClassBug() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/basic/common/NestedClassBug.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("NestedClassNameForExtension.kt")
         public void testNestedClassNameForExtension() throws Exception {
             String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/basic/common/NestedClassNameForExtension.kt");