'Project Structure' dialog: process possible usages from unloaded modules

This is also needed to avoid reporting project libraries used from unloaded modules only as unused.

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/GeneralProjectSettingsElement.java

@@ -18,22 +18,23 @@ package com.intellij.openapi.roots.ui.configuration;
 import com.intellij.compiler.ModuleCompilerUtil;
 import com.intellij.compiler.ModuleSourceSet;
 import com.intellij.openapi.module.Module;
+import com.intellij.openapi.module.ModuleManager;
+import com.intellij.openapi.module.UnloadedModuleDescription;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.project.ProjectBundle;
 import com.intellij.openapi.projectRoots.Sdk;
 import com.intellij.openapi.roots.ModuleRootModel;
+import com.intellij.openapi.roots.libraries.Library;
 import com.intellij.openapi.roots.ui.configuration.projectRoot.ProjectSdksModel;
 import com.intellij.openapi.roots.ui.configuration.projectRoot.StructureConfigurableContext;
 import com.intellij.openapi.roots.ui.configuration.projectRoot.daemon.*;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.util.Chunk;
+import com.intellij.util.containers.MultiMap;
 import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-import java.util.Set;
+import java.util.*;
 
 /**
  * @author nik
@@ -123,6 +124,30 @@ public class GeneralProjectSettingsElement extends ProjectStructureElement {
 
   @Override
   public List<ProjectStructureElementUsage> getUsagesInElement() {
+    Collection<UnloadedModuleDescription> unloadedModules = ModuleManager.getInstance(myContext.getProject()).getUnloadedModuleDescriptions();
+    if (!unloadedModules.isEmpty()) {
+      MultiMap<Module, UnloadedModuleDescription> dependenciesInUnloadedModules = new MultiMap<>();
+      for (UnloadedModuleDescription unloaded : unloadedModules) {
+        for (String moduleName : unloaded.getDependencyModuleNames()) {
+          Module depModule = myContext.getModulesConfigurator().getModuleModel().findModuleByName(moduleName);
+          if (depModule != null) {
+            dependenciesInUnloadedModules.putValue(depModule, unloaded);
+          }
+        }
+      }
+
+      List<ProjectStructureElementUsage> usages = new ArrayList<>();
+      for (Map.Entry<Module, Collection<UnloadedModuleDescription>> entry : dependenciesInUnloadedModules.entrySet()) {
+        usages.add(new UsagesInUnloadedModules(myContext, this, new ModuleProjectStructureElement(myContext, entry.getKey()),
+                                               entry.getValue()));
+      }
+
+      //currently we don't store dependencies on project libraries from unloaded modules in the model, so suppose that all the project libraries are used
+      for (Library library : myContext.getProjectLibrariesProvider().getModifiableModel().getLibraries()) {
+        usages.add(new UsagesInUnloadedModules(myContext, this, new LibraryProjectStructureElement(myContext, library), unloadedModules));
+      }
+      return usages;
+    }
     return Collections.emptyList();
   }
 

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/projectRoot/daemon/UsagesInUnloadedModules.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2000-2017 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 com.intellij.openapi.roots.ui.configuration.projectRoot.daemon;
+
+import com.intellij.icons.AllIcons;
+import com.intellij.openapi.module.UnloadedModuleDescription;
+import com.intellij.openapi.roots.ui.configuration.GeneralProjectSettingsElement;
+import com.intellij.openapi.roots.ui.configuration.ProjectStructureConfigurable;
+import com.intellij.openapi.roots.ui.configuration.projectRoot.StructureConfigurableContext;
+import com.intellij.ui.navigation.Place;
+import com.intellij.util.ObjectUtils;
+import com.intellij.util.containers.ContainerUtil;
+
+import javax.swing.*;
+import java.util.Collection;
+
+/**
+ * @author nik
+ */
+public class UsagesInUnloadedModules extends ProjectStructureElementUsage {
+  private final StructureConfigurableContext myContext;
+  private final GeneralProjectSettingsElement myContainingElement;
+  private final ProjectStructureElement mySourceElement;
+  private final String myPresentableName;
+
+  public UsagesInUnloadedModules(StructureConfigurableContext context, GeneralProjectSettingsElement element,
+                                 ProjectStructureElement sourceElement, Collection<UnloadedModuleDescription> unloadedModules) {
+    myContext = context;
+    myContainingElement = element;
+    mySourceElement = sourceElement;
+    myPresentableName =
+      unloadedModules.size() > 1 ? unloadedModules.size() + " Unloaded Modules"
+                                 : "Unloaded Module '" + ObjectUtils.notNull(ContainerUtil.getFirstItem(unloadedModules)).getName() + "'";
+  }
+
+  @Override
+  public ProjectStructureElement getSourceElement() {
+    return mySourceElement;
+  }
+
+  @Override
+  public ProjectStructureElement getContainingElement() {
+    return myContainingElement;
+  }
+
+  @Override
+  public String getPresentableName() {
+    return myPresentableName;
+  }
+
+  @Override
+  public PlaceInProjectStructure getPlace() {
+    Place configurablePlace = ProjectStructureConfigurable.getInstance(myContext.getProject()).createProjectConfigurablePlace();
+    return new PlaceInProjectStructureBase(myContext.getProject(), configurablePlace, myContainingElement);
+  }
+
+  @Override
+  public void removeSourceElement() {
+  }
+
+  @Override
+  public void replaceElement(ProjectStructureElement newElement) {
+
+  }
+
+  @Override
+  public Icon getIcon() {
+    return AllIcons.Modules.UnloadedModule;
+  }
+
+  @Override
+  public int hashCode() {
+    return 0;
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    return obj instanceof UsagesInUnloadedModules;
+  }
+}