avoid CompletionService/EncodingManager creation if not need

platform/core-api/src/com/intellij/openapi/components/ServiceManager.java

@@ -35,6 +35,11 @@ public class ServiceManager {
     return doGetService(project, serviceClass, false);
   }
 
+  @Nullable
+  public static <T> T getServiceIfCreated(@NotNull Class<T> serviceClass) {
+    return doGetService(ApplicationManager.getApplication(), serviceClass, false);
+  }
+
   @Nullable
   private static <T> T doGetService(ComponentManager componentManager, @NotNull Class<T> serviceClass, boolean isCreate) {
     String componentKey = serviceClass.getName();

platform/lang-impl/src/com/intellij/codeInsight/completion/CompletionProgressIndicator.java

@@ -23,6 +23,7 @@ import com.intellij.openapi.actionSystem.IdeActions;
 import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.command.CommandProcessor;
 import com.intellij.openapi.command.WriteCommandAction;
+import com.intellij.openapi.components.ServiceManager;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.Caret;
 import com.intellij.openapi.editor.Document;
@@ -64,9 +65,9 @@ import java.awt.*;
 import java.awt.event.KeyAdapter;
 import java.awt.event.KeyEvent;
 import java.beans.PropertyChangeListener;
-import java.util.*;
 import java.util.List;
 import java.util.Queue;
+import java.util.*;
 import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Supplier;
@@ -175,6 +176,7 @@ public class CompletionProgressIndicator extends ProgressIndicatorBase implement
     myHandler.lookupItemSelected(this, lookupItem, completionChar, myLookup.getItems());
   }
 
+  @Override
   @NotNull
   @SuppressWarnings("WeakerAccess")
   public OffsetMap getOffsetMap() {
@@ -340,6 +342,7 @@ public class CompletionProgressIndicator extends ProgressIndicatorBase implement
     myParameters = parameters;
   }
 
+  @Override
   public LookupImpl getLookup() {
     return myLookup;
   }
@@ -523,7 +526,12 @@ public class CompletionProgressIndicator extends ProgressIndicatorBase implement
 
   @TestOnly
   public static void cleanupForNextTest() {
-    CompletionProgressIndicator currentCompletion = CompletionServiceImpl.getCompletionService().getCurrentCompletion();
+    CompletionService completionService = ServiceManager.getServiceIfCreated(CompletionService.class);
+    if (!(completionService instanceof CompletionServiceImpl)) {
+      return;
+    }
+
+    CompletionProgressIndicator currentCompletion = ((CompletionServiceImpl)completionService).getCurrentCompletion();
     if (currentCompletion != null) {
       currentCompletion.finishCompletionProcess(true);
       CompletionServiceImpl.assertPhase(CompletionPhase.NoCompletion.getClass());
@@ -635,6 +643,7 @@ public class CompletionProgressIndicator extends ProgressIndicatorBase implement
     return reused ? Math.max(myInvocationCount + 1, 2) : invocation;
   }
 
+  @Override
   @NotNull
   public Editor getEditor() {
     return myEditor;
@@ -663,6 +672,7 @@ public class CompletionProgressIndicator extends ProgressIndicatorBase implement
     return myInvocationCount == 0;
   }
 
+  @Override
   @NotNull
   public Project getProject() {
     return ObjectUtils.assertNotNull(myEditor.getProject());

platform/platform-tests/testSrc/com/intellij/usages/impl/UsageViewTest.java

@@ -1,6 +1,4 @@
-/*
- * Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
- */
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.usages.impl;
 
 import com.intellij.find.FindManager;
@@ -20,14 +18,13 @@ import com.intellij.openapi.progress.ProgressManager;
 import com.intellij.openapi.progress.Task;
 import com.intellij.openapi.util.Disposer;
 import com.intellij.openapi.util.text.StringUtil;
-import com.intellij.openapi.vfs.encoding.EncodingManager;
-import com.intellij.openapi.vfs.encoding.EncodingManagerImpl;
 import com.intellij.psi.PsiDocumentManager;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiFile;
 import com.intellij.psi.PsiNamedElement;
 import com.intellij.psi.impl.source.PsiFileImpl;
 import com.intellij.testFramework.LeakHunter;
+import com.intellij.testFramework.LightPlatformTestCase;
 import com.intellij.testFramework.fixtures.LightPlatformCodeInsightFixtureTestCase;
 import com.intellij.usageView.UsageInfo;
 import com.intellij.usages.*;
@@ -62,7 +59,7 @@ public class UsageViewTest extends LightPlatformCodeInsightFixtureTestCase {
 
     UsageView usageView = createUsageView(usages);
 
-    ((EncodingManagerImpl)EncodingManager.getInstance()).clearDocumentQueue();
+    LightPlatformTestCase.clearEncodingManagerDocumentQueue();
     FileDocumentManager.getInstance().saveAllDocuments();
     UIUtil.dispatchAllInvocationEvents();
 

platform/testFramework/src/com/intellij/testFramework/LightPlatformTestCase.java

@@ -28,6 +28,7 @@ import com.intellij.openapi.command.impl.DocumentReferenceManagerImpl;
 import com.intellij.openapi.command.impl.UndoManagerImpl;
 import com.intellij.openapi.command.undo.DocumentReferenceManager;
 import com.intellij.openapi.command.undo.UndoManager;
+import com.intellij.openapi.components.ServiceManager;
 import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.editor.EditorFactory;
@@ -413,10 +414,7 @@ public abstract class LightPlatformTestCase extends UsefulTestCase implements Da
       })).
       append(() -> assertFalse(PsiManager.getInstance(project).isDisposed())).
       append(() -> {
-        EncodingManager encodingManager = EncodingManager.getInstance();
-        if (encodingManager instanceof EncodingManagerImpl) {
-          ((EncodingManagerImpl)encodingManager).clearDocumentQueue();
-        }
+        clearEncodingManagerDocumentQueue();
 
         if (!ourAssertionsInTestDetected) {
           if (IdeaLogger.ourErrorsOccurred != null) {
@@ -445,6 +443,13 @@ public abstract class LightPlatformTestCase extends UsefulTestCase implements Da
       run();
   }
 
+  public static void clearEncodingManagerDocumentQueue() {
+    EncodingManager encodingManager = ServiceManager.getServiceIfCreated(EncodingManager.class);
+    if (encodingManager instanceof EncodingManagerImpl) {
+      ((EncodingManagerImpl)encodingManager).clearDocumentQueue();
+    }
+  }
+
   private static int ourTestCount;
 
   @ReviseWhenPortedToJDK("9")