Accessing of default parameter value in compiled code via source (if found)

idea/idea-analysis/src/org/jetbrains/kotlin/idea/decompiler/KotlinClsFileBase.kt

@@ -20,18 +20,29 @@ import com.intellij.openapi.util.TextRange
 import com.intellij.psi.FileViewProvider
 import com.intellij.psi.util.PsiTreeUtil
 import org.jetbrains.annotations.TestOnly
+import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 import org.jetbrains.kotlin.idea.decompiler.textBuilder.DecompiledText
-import org.jetbrains.kotlin.psi.JetDeclaration
 import org.jetbrains.kotlin.idea.decompiler.textBuilder.descriptorToKey
-import org.jetbrains.kotlin.utils.concurrent.block.LockedClearableLazyValue
+import org.jetbrains.kotlin.psi.JetCallableDeclaration
+import org.jetbrains.kotlin.psi.JetDeclaration
 import org.jetbrains.kotlin.psi.JetFile
+import org.jetbrains.kotlin.utils.concurrent.block.LockedClearableLazyValue
 
 public abstract class KotlinClsFileBase(provider: FileViewProvider) : JetFile(provider, true) {
     protected abstract val decompiledText: LockedClearableLazyValue<DecompiledText>
 
     public fun getDeclarationForDescriptor(descriptor: DeclarationDescriptor): JetDeclaration? {
-        val key = descriptorToKey(descriptor.getOriginal())
+        val original = descriptor.getOriginal()
+
+        if (original is ValueParameterDescriptor) {
+            val callable = original.getContainingDeclaration() as? CallableDescriptor ?: return null
+            val callableDeclaration = getDeclarationForDescriptor(callable) as? JetCallableDeclaration ?: return null
+            return callableDeclaration.getValueParameters()[original.getIndex()]
+        }
+
+        val key = descriptorToKey(original)
 
         val range = decompiledText.get().renderedDescriptorsToRange[key]
         return if (range != null) {

idea/idea-analysis/src/org/jetbrains/kotlin/idea/decompiler/navigation/JetSourceNavigationHelper.java

@@ -439,6 +439,20 @@ public class JetSourceNavigationHelper {
         public JetDeclaration visitClass(@NotNull JetClass klass, Void data) {
             return getSourceClassOrObject(klass);
         }
+
+        @Override
+        public JetDeclaration visitParameter(@NotNull JetParameter parameter, Void data) {
+            PsiElement pparent = parameter.getParent().getParent();
+            JetCallableDeclaration callableDeclaration = (JetCallableDeclaration) pparent;
+            List<JetParameter> parameters = callableDeclaration.getValueParameters();
+            int index = parameters.indexOf(parameter);
+
+            JetCallableDeclaration sourceCallable = (JetCallableDeclaration) callableDeclaration.accept(this, null);
+            if (sourceCallable == null) return null;
+            List<JetParameter> sourceParameters = sourceCallable.getValueParameters();
+            if (sourceParameters.size() != parameters.size()) return null;
+            return sourceParameters.get(index);
+        }
     }
 
     private static class LibrarySourcesScope extends GlobalSearchScope {

idea/idea-core/src/org/jetbrains/kotlin/idea/core/OptionalParametersHelper.kt

@@ -22,6 +22,7 @@ import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.codeInsight.DescriptorToSourceUtilsIde
+import org.jetbrains.kotlin.idea.decompiler.navigation.JetSourceNavigationHelper
 import org.jetbrains.kotlin.psi.JetExpression
 import org.jetbrains.kotlin.psi.JetParameter
 import org.jetbrains.kotlin.psi.JetSimpleNameExpression
@@ -118,10 +119,14 @@ public object OptionalParametersHelper {
     //TODO: handle implicit receivers
     public fun defaultParameterValue(parameter: ValueParameterDescriptor, project: Project): DefaultValue? {
         if (!parameter.hasDefaultValue()) return null
+
         //TODO: parameter in overriding method!
-        val sourceParameter = DescriptorToSourceUtilsIde.getAnyDeclaration(project, parameter) as? JetParameter ?: return null
-        //TODO: use JetSourceNavigationHelper
-        val expression = sourceParameter.getDefaultValue() ?: return null
+        //TODO: it's a temporary code while we don't have default values accessible from descriptors
+        var declaration = DescriptorToSourceUtilsIde.getAnyDeclaration(project, parameter) as? JetParameter ?: return null
+        if (declaration.getContainingJetFile().isCompiled()) {
+            declaration = JetSourceNavigationHelper.replaceBySourceDeclarationIfPresent(declaration) as? JetParameter ?: return null
+        }
+        val expression = declaration.getDefaultValue() ?: return null
 
         val allParameters = (parameter.getContainingDeclaration() as CallableDescriptor).getValueParameters().toSet()