fail when accessing invalid offsets in completion insert handlers

java/java-impl/src/com/intellij/codeInsight/completion/ConstructorInsertHandler.java

@@ -58,7 +58,7 @@ public class ConstructorInsertHandler implements InsertHandler<LookupElementDeco
 
     boolean isAbstract = psiClass.hasModifierProperty(PsiModifier.ABSTRACT);
 
-    if (Lookup.REPLACE_SELECT_CHAR == context.getCompletionChar()) {
+    if (Lookup.REPLACE_SELECT_CHAR == context.getCompletionChar() && context.getOffsetMap().containsOffset(PARAM_LIST_START)) {
       final int plStart = context.getOffset(PARAM_LIST_START);
       final int plEnd = context.getOffset(PARAM_LIST_END);
       if (plStart >= 0 && plEnd >= 0) {

platform/lang-api/src/com/intellij/codeInsight/completion/OffsetMap.java

@@ -19,10 +19,10 @@ import com.intellij.openapi.Disposable;
 import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.editor.RangeMarker;
 import com.intellij.openapi.progress.ProgressManager;
+import com.intellij.util.containers.ContainerUtil;
 import gnu.trove.THashMap;
 import gnu.trove.THashSet;
 
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -48,10 +48,10 @@ public class OffsetMap implements Disposable {
   public int getOffset(OffsetKey key) {
     synchronized (myMap) {
       final RangeMarker marker = myMap.get(key);
-      if (marker == null) return -1;
+      if (marker == null) throw new IllegalArgumentException("Offset " + key + " is not registered");
       if (!marker.isValid()) {
         removeOffset(key);
-        return -1;
+        throw new IllegalStateException("Offset " + key + " is invalid: " + marker);
       }
 
       final int endOffset = marker.getEndOffset();
@@ -62,6 +62,11 @@ public class OffsetMap implements Disposable {
     }
   }
 
+  public boolean containsOffset(OffsetKey key) {
+    final RangeMarker marker = myMap.get(key);
+    return marker != null && marker.isValid();
+  }
+
   /**
    * Register key-offset binding. Offset will change together with {@link Document} editing operations
    * unless an operation replaces completely the offset vicinity.
@@ -108,7 +113,7 @@ public class OffsetMap implements Disposable {
     synchronized (myMap) {
       ProgressManager.checkCanceled();
       assert !myDisposed;
-      return new ArrayList<OffsetKey>(myMap.keySet());
+      return ContainerUtil.filter(myMap.keySet(), this::containsOffset);
     }
   }
 

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

@@ -566,10 +566,9 @@ public class CodeCompletionHandlerBase {
     final Editor editor = indicator.getEditor();
 
     final int caretOffset = indicator.getCaret().getOffset();
-    int idEndOffset = indicator.getIdentifierEndOffset();
-    if (idEndOffset < 0) {
-      idEndOffset = CompletionInitializationContext.calcDefaultIdentifierEnd(editor, caretOffset);
-    }
+    final int idEndOffset = indicator.getOffsetMap().containsOffset(CompletionInitializationContext.IDENTIFIER_END_OFFSET) ?
+                            indicator.getIdentifierEndOffset() :
+                            CompletionInitializationContext.calcDefaultIdentifierEnd(editor, caretOffset);
     final int idEndOffsetDelta = idEndOffset - caretOffset;
 
     CompletionAssertions.WatchingInsertionContext context;

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

@@ -462,6 +462,10 @@ public class CompletionLookupArranger extends LookupArranger {
       return;
     }
 
+    if (!context.getOffsetMap().containsOffset(CompletionInitializationContext.START_OFFSET)) {
+      return;
+    }
+    
     final Document document = context.getDocument();
     int startOffset = context.getStartOffset();
     int tailOffset = context.getEditor().getCaretModel().getOffset();
@@ -550,7 +554,9 @@ public class CompletionLookupArranger extends LookupArranger {
 
     public void addSparedChars(CompletionProgressIndicator indicator, LookupElement item, InsertionContext context, char completionChar) {
       String textInserted;
-      if (context.getStartOffset() >= 0 && context.getTailOffset() >= context.getStartOffset()) {
+      if (context.getOffsetMap().containsOffset(CompletionInitializationContext.START_OFFSET) && 
+          context.getOffsetMap().containsOffset(InsertionContext.TAIL_OFFSET) && 
+          context.getTailOffset() >= context.getStartOffset()) {
         textInserted = context.getDocument().getImmutableCharSequence().subSequence(context.getStartOffset(), context.getTailOffset()).toString();
       } else {
         textInserted = item.getLookupString();