Completion of parameter name+type works for val/var parameters

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/CompletionSession.kt

@@ -263,13 +263,14 @@ class BasicCompletionSession(configuration: CompletionSessionConfiguration,
                              resultSet: CompletionResultSet)
 : CompletionSessionBase(configuration, parameters, resultSet) {
 
-    public enum class CompletionKind {
-        KEYWORDS_ONLY,
-        NAMED_ARGUMENTS_ONLY,
-        ALL,
-        TYPES,
-        ANNOTATION_TYPES,
-        ANNOTATION_TYPES_OR_PARAMETER_NAME
+    public enum class CompletionKind(val classKindFilter: ((ClassKind) -> Boolean)?) {
+        KEYWORDS_ONLY(classKindFilter = null),
+        NAMED_ARGUMENTS_ONLY(classKindFilter = null),
+        ALL(classKindFilter = { it != ClassKind.ENUM_ENTRY }),
+        TYPES(classKindFilter = { it != ClassKind.ENUM_ENTRY }),
+        ANNOTATION_TYPES(classKindFilter = { it == ClassKind.ANNOTATION_CLASS }),
+        ANNOTATION_TYPES_OR_PARAMETER_NAME(classKindFilter = { it == ClassKind.ANNOTATION_CLASS }),
+        PARAMETER_NAME(classKindFilter = null)
     }
 
     public val completionKind: CompletionKind = calcCompletionKind()
@@ -284,12 +285,12 @@ class BasicCompletionSession(configuration: CompletionSessionConfiguration,
         CompletionKind.ALL ->
             DescriptorKindFilter(DescriptorKindFilter.ALL_KINDS_MASK)
 
-        CompletionKind.NAMED_ARGUMENTS_ONLY, CompletionKind.KEYWORDS_ONLY ->
+        CompletionKind.NAMED_ARGUMENTS_ONLY, CompletionKind.KEYWORDS_ONLY, CompletionKind.PARAMETER_NAME ->
             null
     }
 
-    private val parameterNameAndTypeCompletion = if (completionKind == CompletionKind.ANNOTATION_TYPES_OR_PARAMETER_NAME)
-        ParameterNameAndTypeCompletion(collector, lookupElementFactory, prefixMatcher)
+    private val parameterNameAndTypeCompletion = if (completionKind == CompletionKind.PARAMETER_NAME || completionKind == CompletionKind.ANNOTATION_TYPES_OR_PARAMETER_NAME)
+        ParameterNameAndTypeCompletion(collector, lookupElementFactory, prefixMatcher, resolutionFacade)
     else
         null
 
@@ -299,7 +300,11 @@ class BasicCompletionSession(configuration: CompletionSessionConfiguration,
         }
 
         if (reference == null) {
-            return CompletionKind.KEYWORDS_ONLY
+            val parameter = position.getParent() as? JetParameter
+            return if (parameter != null && position == parameter.getNameIdentifier())
+                CompletionKind.PARAMETER_NAME
+            else
+                CompletionKind.KEYWORDS_ONLY
         }
 
         val annotationEntry = position.getStrictParentOfType<JetAnnotationEntry>()
@@ -333,7 +338,7 @@ class BasicCompletionSession(configuration: CompletionSessionConfiguration,
         if (completionKind != CompletionKind.NAMED_ARGUMENTS_ONLY) {
             collector.addDescriptorElements(referenceVariants, suppressAutoInsertion = false)
 
-            parameterNameAndTypeCompletion?.addFromImports(reference!!.expression, bindingContext, { isVisibleDescriptor(it) })
+            parameterNameAndTypeCompletion?.addFromImports(position, bindingContext, { isVisibleDescriptor(it) })
 
             val keywordsPrefix = prefix.substringBefore('@') // if there is '@' in the prefix - use shorter prefix to not loose 'this' etc
             KeywordCompletion.complete(expression ?: parameters.getPosition(), keywordsPrefix) { lookupElement ->
@@ -402,12 +407,7 @@ class BasicCompletionSession(configuration: CompletionSessionConfiguration,
         flushToResultSet()
 
         if (shouldRunTopLevelCompletion()) {
-            addAllClasses {
-                if (completionKind != CompletionKind.ANNOTATION_TYPES && completionKind != CompletionKind.ANNOTATION_TYPES_OR_PARAMETER_NAME)
-                    it != ClassKind.ENUM_ENTRY
-                else
-                    it == ClassKind.ANNOTATION_CLASS
-            }
+            completionKind.classKindFilter?.let { addAllClasses(it) }
 
             if (completionKind == CompletionKind.ALL) {
                 collector.addDescriptorElements(getTopLevelCallables(), suppressAutoInsertion = true)

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/ParameterNameAndTypeCompletion.kt

@@ -23,29 +23,37 @@ import com.intellij.codeInsight.lookup.LookupElement
 import com.intellij.codeInsight.lookup.LookupElementDecorator
 import com.intellij.codeInsight.lookup.LookupElementPresentation
 import com.intellij.psi.PsiClass
+import com.intellij.psi.PsiElement
 import com.intellij.psi.codeStyle.CodeStyleSettingsManager
+import org.jetbrains.kotlin.descriptors.ClassDescriptorWithResolutionScopes
 import org.jetbrains.kotlin.descriptors.ClassifierDescriptor
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.idea.caches.resolve.ResolutionFacade
 import org.jetbrains.kotlin.idea.core.KotlinIndicesHelper
 import org.jetbrains.kotlin.idea.core.formatter.JetCodeStyleSettings
 import org.jetbrains.kotlin.idea.core.refactoring.EmptyValidator
 import org.jetbrains.kotlin.idea.core.refactoring.JetNameSuggester
-import org.jetbrains.kotlin.psi.JetSimpleNameExpression
+import org.jetbrains.kotlin.psi.JetClassOrObject
+import org.jetbrains.kotlin.psi.JetExpression
+import org.jetbrains.kotlin.psi.JetFile
+import org.jetbrains.kotlin.psi.psiUtil.parentsWithSelf
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.scopes.DescriptorKindFilter
+import org.jetbrains.kotlin.resolve.scopes.JetScope
 import org.jetbrains.kotlin.resolve.scopes.getDescriptorsFiltered
 
 class ParameterNameAndTypeCompletion(
         private val collector: LookupElementsCollector,
         private val lookupElementFactory: LookupElementFactory,
-        private val prefixMatcher: PrefixMatcher
+        private val prefixMatcher: PrefixMatcher,
+        private val resolutionFacade: ResolutionFacade
 ) {
     private val modifiedPrefixMatcher = prefixMatcher.cloneWithPrefix(prefixMatcher.getPrefix().capitalize())
 
-    public fun addFromImports(nameExpression: JetSimpleNameExpression, bindingContext: BindingContext, visibilityFilter: (DeclarationDescriptor) -> Boolean) {
+    public fun addFromImports(context: PsiElement, bindingContext: BindingContext, visibilityFilter: (DeclarationDescriptor) -> Boolean) {
         if (prefixMatcher.getPrefix().isEmpty()) return
 
-        val resolutionScope = bindingContext[BindingContext.RESOLUTION_SCOPE, nameExpression] ?: return
+        val resolutionScope = context.getResolutionScope(bindingContext)
         val classifiers = resolutionScope.getDescriptorsFiltered(DescriptorKindFilter.NON_SINGLETON_CLASSIFIERS, modifiedPrefixMatcher.asNameFilter())
 
         for (classifier in classifiers) {
@@ -55,6 +63,27 @@ class ParameterNameAndTypeCompletion(
         }
     }
 
+    private fun PsiElement.getResolutionScope(bindingContext: BindingContext): JetScope {
+        for (parent in parentsWithSelf) {
+            if (parent is JetExpression) {
+                val scope = bindingContext[BindingContext.RESOLUTION_SCOPE, parent]
+                if (scope != null) return scope
+            }
+
+            if (parent is JetClassOrObject) {
+                val classDescriptor = bindingContext[BindingContext.CLASS, parent] as? ClassDescriptorWithResolutionScopes
+                if (classDescriptor != null) {
+                    return classDescriptor.getScopeForMemberDeclarationResolution()
+                }
+            }
+
+            if (parent is JetFile) {
+                return resolutionFacade.getFileTopLevelScope(parent)
+            }
+        }
+        error("Not in JetFile")
+    }
+
     public fun addAll(parameters: CompletionParameters, indicesHelper: KotlinIndicesHelper) {
         if (prefixMatcher.getPrefix().isEmpty()) return
 

idea/idea-completion/testData/basic/common/parameterNameAndType/ValParameter.kt

@@ -0,0 +1,11 @@
+package pack
+
+class FooBar
+
+class Boo
+
+class C(val b<caret>)
+
+// EXIST: { lookupString: "bar", itemText: "bar: FooBar", tailText: " (pack)" }
+// EXIST: { lookupString: "fooBar", itemText: "fooBar: FooBar", tailText: " (pack)" }
+// EXIST: { lookupString: "boo", itemText: "boo: Boo", tailText: " (pack)" }

idea/idea-completion/testData/basic/common/parameterNameAndType/VarParameter.kt

@@ -0,0 +1,11 @@
+package pack
+
+class FooBar
+
+class C(private var b<caret>) {
+    class Boo
+}
+
+// EXIST: { lookupString: "bar", itemText: "bar: FooBar", tailText: " (pack)" }
+// EXIST: { lookupString: "fooBar", itemText: "fooBar: FooBar", tailText: " (pack)" }
+// EXIST: { lookupString: "boo", itemText: "boo: Boo", tailText: " (pack.C)" }

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

@@ -1427,6 +1427,18 @@ public class JSBasicCompletionTestGenerated extends AbstractJSBasicCompletionTes
                 String fileName = JetTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/parameterNameAndType/Simple.kt");
                 doTest(fileName);
             }
+
+            @TestMetadata("ValParameter.kt")
+            public void testValParameter() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/parameterNameAndType/ValParameter.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("VarParameter.kt")
+            public void testVarParameter() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/parameterNameAndType/VarParameter.kt");
+                doTest(fileName);
+            }
         }
 
         @TestMetadata("idea/idea-completion/testData/basic/common/shadowing")

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

@@ -1427,6 +1427,18 @@ public class JvmBasicCompletionTestGenerated extends AbstractJvmBasicCompletionT
                 String fileName = JetTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/parameterNameAndType/Simple.kt");
                 doTest(fileName);
             }
+
+            @TestMetadata("ValParameter.kt")
+            public void testValParameter() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/parameterNameAndType/ValParameter.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("VarParameter.kt")
+            public void testVarParameter() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/parameterNameAndType/VarParameter.kt");
+                doTest(fileName);
+            }
         }
 
         @TestMetadata("idea/idea-completion/testData/basic/common/shadowing")