Navigation from header to implementation and vice versa #KT-15204 Fixed

compiler/frontend/src/org/jetbrains/kotlin/resolve/checkers/HeaderImplDeclarationChecker.kt

@@ -131,7 +131,7 @@ class HeaderImplDeclarationChecker(val moduleToCheck: ModuleDescriptor? = null)
         }
     }
 
-    private fun CallableMemberDescriptor.findNamesakesFromTheSameModule(): Collection<CallableMemberDescriptor> {
+    fun CallableMemberDescriptor.findNamesakesFromTheSameModule(): Collection<CallableMemberDescriptor> {
         val packageFqName = (containingDeclaration as? PackageFragmentDescriptor)?.fqName ?: return emptyList()
         val myModule = moduleToCheck ?: module
         val scope = myModule.getPackage(packageFqName).memberScope
@@ -145,7 +145,7 @@ class HeaderImplDeclarationChecker(val moduleToCheck: ModuleDescriptor? = null)
         }
     }
 
-    private fun ClassifierDescriptor.findClassifiersFromTheSameModule(): Collection<ClassifierDescriptor> {
+    fun ClassifierDescriptor.findClassifiersFromTheSameModule(): Collection<ClassifierDescriptor> {
         val myModule = moduleToCheck ?: module
         // TODO: support nested classes
         return myModule.getPackage(fqNameSafe.parent()).memberScope

idea/src/org/jetbrains/kotlin/idea/highlighter/markers/DeclaredHeaderMarker.kt

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2010-2016 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.idea.highlighter.markers
+
+import com.intellij.psi.NavigatablePsiElement
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.idea.caches.resolve.findModuleDescriptor
+import org.jetbrains.kotlin.idea.core.toDescriptor
+import org.jetbrains.kotlin.psi.KtDeclaration
+import org.jetbrains.kotlin.resolve.DescriptorToSourceUtils
+import org.jetbrains.kotlin.resolve.checkers.HeaderImplDeclarationChecker
+
+fun ModuleDescriptor.commonModuleOrNull() = allDependencyModules.filter {
+    it.platformKind == PlatformKind.DEFAULT && it.sourceKind == sourceKind
+}.firstOrNull()
+
+fun ModuleDescriptor.hasDeclarationOf(descriptor: MemberDescriptor) = declarationOf(descriptor) != null
+
+private fun ModuleDescriptor.declarationOf(descriptor: MemberDescriptor) =
+        with (HeaderImplDeclarationChecker(this)) {
+            when (descriptor) {
+                is CallableMemberDescriptor ->
+                    descriptor.findNamesakesFromTheSameModule().filter { it.isHeader }.firstOrNull()
+                is ClassDescriptor ->
+                    descriptor.findClassifiersFromTheSameModule().filter { it is ClassDescriptor && it.isHeader }.firstOrNull()
+                else ->
+                    null
+            }
+        }
+
+fun getHeaderDeclarationTooltip(declaration: KtDeclaration): String? {
+    val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return null
+    val platformModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
+
+    val commonModuleDescriptor = platformModuleDescriptor.commonModuleOrNull() ?: return null
+    if (!commonModuleDescriptor.hasDeclarationOf(descriptor)) return null
+
+    return "Has declaration in common module"
+}
+
+fun navigateToHeaderDeclaration(declaration: KtDeclaration) {
+    val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return
+    val platformModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
+
+    val commonModuleDescriptor = platformModuleDescriptor.commonModuleOrNull() ?: return
+    val headerDeclaration = DescriptorToSourceUtils.descriptorToDeclaration(
+            commonModuleDescriptor.declarationOf(descriptor) ?: return
+    ) as? NavigatablePsiElement ?: return
+
+    headerDeclaration.navigate(false)
+}

idea/src/org/jetbrains/kotlin/idea/highlighter/markers/ImplementedHeaderMarker.kt

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2010-2016 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.idea.highlighter.markers
+
+import com.intellij.codeInsight.daemon.impl.PsiElementListNavigator
+import com.intellij.ide.util.DefaultPsiElementCellRenderer
+import com.intellij.psi.NavigatablePsiElement
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.idea.caches.resolve.findModuleDescriptor
+import org.jetbrains.kotlin.idea.core.toDescriptor
+import org.jetbrains.kotlin.psi.KtDeclaration
+import org.jetbrains.kotlin.resolve.DescriptorToSourceUtils
+import org.jetbrains.kotlin.resolve.checkers.HeaderImplDeclarationChecker
+import java.awt.event.MouseEvent
+
+fun ModuleDescriptor.hasImplementationsOf(descriptor: MemberDescriptor) =
+        implementationsOf(descriptor).isNotEmpty()
+
+private fun ModuleDescriptor.implementationsOf(descriptor: MemberDescriptor) =
+        with (HeaderImplDeclarationChecker(this)) {
+            when (descriptor) {
+                is CallableMemberDescriptor -> descriptor.findNamesakesFromTheSameModule().filter { it.isImpl }
+                is ClassDescriptor -> descriptor.findClassifiersFromTheSameModule().filter { it is ClassDescriptor && it.isImpl }
+                else -> emptyList()
+            }
+        }
+
+fun getPlatformImplementationTooltip(declaration: KtDeclaration): String? {
+    val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return null
+    val commonModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
+
+    val platformModulesWithImplementation = commonModuleDescriptor.allImplementingModules.filter {
+        it.hasImplementationsOf(descriptor)
+    }
+    if (platformModulesWithImplementation.isEmpty()) return null
+
+    return platformModulesWithImplementation.joinToString(prefix = "Has implementations in ") {
+        it.platformKind.name
+    }
+}
+
+fun navigateToPlatformImplementation(e: MouseEvent?, declaration: KtDeclaration) {
+    val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return
+    val commonModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
+
+    val implementations = commonModuleDescriptor.allImplementingModules.flatMap {
+        it.implementationsOf(descriptor)
+    }.mapNotNull { DescriptorToSourceUtils.descriptorToDeclaration(it) as? NavigatablePsiElement }
+    if (implementations.isEmpty()) return
+
+    val renderer = DefaultPsiElementCellRenderer()
+    PsiElementListNavigator.openTargets(e,
+                                        implementations.toTypedArray(),
+                                        "Choose implementation of ${declaration.name}",
+                                        "Implementations of ${declaration.name}",
+                                        renderer)
+}

idea/src/org/jetbrains/kotlin/idea/highlighter/markers/KotlinLineMarkerProvider.kt

@@ -31,8 +31,9 @@ import com.intellij.psi.PsiNameIdentifierOwner
 import com.intellij.psi.search.searches.ClassInheritorsSearch
 import org.jetbrains.kotlin.asJava.LightClassUtil
 import org.jetbrains.kotlin.asJava.toLightClass
-import org.jetbrains.kotlin.descriptors.CallableMemberDescriptor
+import org.jetbrains.kotlin.descriptors.*
-import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.idea.caches.resolve.findModuleDescriptor
+import org.jetbrains.kotlin.idea.core.toDescriptor
 import org.jetbrains.kotlin.idea.util.ProjectRootsUtil
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
@@ -78,6 +79,15 @@ class KotlinLineMarkerProvider : LineMarkerProvider {
                     }
                 }
             }
+
+            if (element is KtNamedDeclaration) {
+                if (element.hasModifier(KtTokens.HEADER_KEYWORD)) {
+                    collectImplementationMarkers(element, result)
+                }
+                else if (element.hasModifier(KtTokens.IMPL_KEYWORD)) {
+                    collectHeaderMarkers(element, result)
+                }
+            }
         }
 
         collectOverriddenFunctions(functions, result)
@@ -114,6 +124,26 @@ private val OVERRIDDEN_PROPERTY = MarkerType(
             }
         })
 
+private val PLATFORM_IMPLEMENTATION = MarkerType(
+        "PLATFORM_IMPLEMENTATION",
+        { it?.let { getPlatformImplementationTooltip(it.parent as KtDeclaration) } },
+        object : LineMarkerNavigator() {
+            override fun browse(e: MouseEvent?, element: PsiElement?) {
+                element?.let { navigateToPlatformImplementation(e, it.parent as KtDeclaration) }
+            }
+        }
+)
+
+private val HEADER_DECLARATION = MarkerType(
+        "HEADER_DECLARATION",
+        { it?.let { getHeaderDeclarationTooltip(it.parent as KtDeclaration) } },
+        object : LineMarkerNavigator() {
+            override fun browse(e: MouseEvent?, element: PsiElement?) {
+                element?.let { navigateToHeaderDeclaration(it.parent as KtDeclaration) }
+            }
+        }
+)
+
 private fun isImplementsAndNotOverrides(descriptor: CallableMemberDescriptor, overriddenMembers: Collection<CallableMemberDescriptor>): Boolean {
     return descriptor.modality != Modality.ABSTRACT && overriddenMembers.all { it.modality == Modality.ABSTRACT }
 }
@@ -196,6 +226,48 @@ private fun collectOverriddenPropertyAccessors(properties: Collection<KtNamedDec
     }
 }
 
+private fun collectImplementationMarkers(declaration: KtNamedDeclaration,
+                                         result: MutableCollection<LineMarkerInfo<*>>) {
+
+    val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return
+    val commonModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
+
+    if (commonModuleDescriptor.allImplementingModules.none { it.hasImplementationsOf(descriptor) }) return
+
+    val anchor = declaration.nameIdentifier ?: declaration
+
+    result.add(LineMarkerInfo(
+            anchor,
+            anchor.textRange,
+            IMPLEMENTED_MARK,
+            Pass.UPDATE_OVERRIDDEN_MARKERS,
+            PLATFORM_IMPLEMENTATION.tooltip,
+            PLATFORM_IMPLEMENTATION.navigationHandler,
+            GutterIconRenderer.Alignment.RIGHT
+    ))
+}
+
+private fun collectHeaderMarkers(declaration: KtNamedDeclaration,
+                                 result: MutableCollection<LineMarkerInfo<*>>) {
+
+    val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return
+    val platformModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
+    val commonModuleDescriptor = platformModuleDescriptor.commonModuleOrNull() ?: return
+    if (!commonModuleDescriptor.hasDeclarationOf(descriptor)) return
+
+    val anchor = declaration.nameIdentifier ?: declaration
+
+    result.add(LineMarkerInfo(
+            anchor,
+            anchor.textRange,
+            IMPLEMENTING_MARK,
+            Pass.UPDATE_OVERRIDDEN_MARKERS,
+            HEADER_DECLARATION.tooltip,
+            HEADER_DECLARATION.navigationHandler,
+            GutterIconRenderer.Alignment.RIGHT
+    ))
+}
+
 fun KtNamedDeclaration.getAccessorLightMethods(): LightClassUtil.PropertyAccessorsPsiMethods {
     return when (this) {
         is KtProperty -> LightClassUtil.getLightClassPropertyMethods(this)