java completion: suggest ref[0] in basic completion as we do in smart one (towards IDEA-145958)

GitOrigin-RevId: 26c336f486c3e7c8a94bee43df52d559821807f9

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

@@ -264,21 +264,21 @@ public class JavaCompletionContributor extends CompletionContributor {
         result.stopHere();
       }
 
-      List<LookupElement> referenceSuggestions = parent instanceof PsiJavaCodeReferenceElement && mayCompleteReference
+      List<LookupElement> refBasedSuggestions = parent instanceof PsiJavaCodeReferenceElement && mayCompleteReference
                                                  ? completeReference(parameters, (PsiJavaCodeReferenceElement)parent, session)
                                                  : Collections.emptyList();
       if (!smart) {
         TailType switchLabelTail = IN_SWITCH_LABEL.accepts(position)
                                    ? TailTypes.forSwitchLabel(Objects.requireNonNull(PsiTreeUtil.getParentOfType(position, PsiSwitchBlock.class)))
                                    : null;
-        session.registerBatchItems(ContainerUtil.map(referenceSuggestions, e -> switchLabelTail != null ? new IndentingDecorator(TailTypeDecorator.withTail(e, switchLabelTail)) : e));
+        session.registerBatchItems(ContainerUtil.map(refBasedSuggestions, e -> switchLabelTail != null ? new IndentingDecorator(TailTypeDecorator.withTail(e, switchLabelTail)) : e));
         result.stopHere();
       }
 
       session.flushBatchItems();
 
       if (smart) {
-        addSmartCompletionSuggestions(parameters, result, referenceSuggestions);
+        addSmartCompletionSuggestions(parameters, result, refBasedSuggestions);
       }
     }
 
@@ -573,6 +573,9 @@ public class JavaCompletionContributor extends CompletionContributor {
         }
       }
       items.add(element);
+
+      ContainerUtil.addIfNotNull(items, ArrayMemberAccess.accessFirstElement(position, element));
+
     }
     return items;
   }

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

@@ -3,7 +3,6 @@ package com.intellij.codeInsight.completion;
 
 import com.intellij.codeInsight.ExpectedTypeInfo;
 import com.intellij.codeInsight.lookup.AutoCompletionPolicy;
-import com.intellij.codeInsight.lookup.ExpressionLookupItem;
 import com.intellij.codeInsight.lookup.LookupElement;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.patterns.StandardPatterns;
@@ -79,8 +78,6 @@ public class ReferenceExpressionCompletionContributor {
     ElementFilter filter = getReferenceFilter(element, false);
     allRefSuggestions = ContainerUtil.filter(allRefSuggestions, item -> filter.isAcceptable(item.getObject(), element));
 
-    Set<LookupElement> base = new HashSet<>(allRefSuggestions);
-
     for (ExpectedTypeInfo info : infos) {
       for (LookupElement item : allRefSuggestions) {
         if (matchesExpectedType(item, info.getType())) {
@@ -89,19 +86,10 @@ public class ReferenceExpressionCompletionContributor {
           }
           result.consume(item);
         }
-
-        ExpressionLookupItem access = ArrayMemberAccess.accessFirstElement(element, item);
-        if (access != null) {
-          base.add(access);
-          PsiType type = access.getType();
-          if (type != null && info.getType().isAssignableFrom(type)) {
-            result.consume(access);
-          }
-        }
       }
 
       if (parameters.getInvocationCount() >= 2) {
-        chainedEtc.add(new SlowerTypeConversions(base, element, (PsiJavaCodeReferenceElement) element.getParent(),
+        chainedEtc.add(new SlowerTypeConversions(new HashSet<>(allRefSuggestions), element, (PsiJavaCodeReferenceElement) element.getParent(),
                                                  new JavaSmartCompletionParameters(parameters, info), result));
       }
     }

java/java-tests/testData/codeInsight/completion/normal/OneElementArray.java

@@ -0,0 +1,8 @@
+public class SomeClass {
+
+  {
+    int[] aaa = new int[1];
+    int bbb = a<caret>
+  }
+
+}

java/java-tests/testData/codeInsight/completion/normal/OneElementArray_after.java

@@ -0,0 +1,8 @@
+public class SomeClass {
+
+  {
+    int[] aaa = new int[1];
+    int bbb = aaa[0]<caret>
+  }
+
+}

java/java-tests/testSrc/com/intellij/java/codeInsight/completion/NormalCompletionTest.groovy

@@ -2005,4 +2005,11 @@ class Abc {
   }
 
   void testCaseColonAfterStringConstant() { doTest() }
+
+  void testOneElementArray() {
+    configureByTestName()
+    myFixture.assertPreferredCompletionItems 0, 'aaa', 'aaa[0]'
+    selectItem(myItems[1])
+    checkResult()
+  }
 }