IDEA-55146 Autocomplete case inside switch

indent, remove duplicates, restore completion after 'case' (IDEA-CR-12610)

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

@@ -54,7 +54,6 @@ import com.intellij.psi.util.PsiUtil;
 import com.intellij.psi.util.PsiUtilCore;
 import com.intellij.psi.util.TypeConversionUtil;
 import com.intellij.util.DocumentUtil;
-import com.intellij.util.PairConsumer;
 import com.intellij.util.ProcessingContext;
 import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.NotNull;
@@ -845,7 +844,7 @@ public class JavaCompletionContributor extends CompletionContributor {
     return null;
   }
 
-  private static class IndentingDecorator extends LookupElementDecorator<LookupElement> {
+  static class IndentingDecorator extends LookupElementDecorator<LookupElement> {
     public IndentingDecorator(LookupElement delegate) {
       super(delegate);
     }

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

@@ -36,6 +36,7 @@ import com.intellij.psi.util.InheritanceUtil;
 import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.util.PsiUtil;
 import com.intellij.util.Consumer;
+import com.intellij.util.ObjectUtils;
 import com.intellij.util.ProcessingContext;
 import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.NotNull;
@@ -303,7 +304,11 @@ public class JavaKeywordCompletion {
   }
 
   private static PsiSwitchStatement getSwitchFromLabelPosition(PsiElement position) {
-    return PsiTreeUtil.getParentOfType(position, PsiSwitchStatement.class, false, PsiMember.class, PsiSwitchLabelStatement.class);
+    PsiStatement statement = PsiTreeUtil.getParentOfType(position, PsiStatement.class, false, PsiMember.class);
+    if (statement != null && !(statement instanceof PsiSwitchLabelStatement) && statement.getParent() instanceof PsiCodeBlock) {
+      return ObjectUtils.tryCast(statement.getParent().getParent(), PsiSwitchStatement.class);
+    }
+    return null;
   }
 
   static void addEnumCases(CompletionResultSet result, PsiElement position) {
@@ -315,12 +320,18 @@ public class JavaKeywordCompletion {
     Set<PsiField> used = ReferenceExpressionCompletionContributor.findConstantsUsedInSwitch(switchStatement);
     for (PsiField field : switchType.getAllFields()) {
       String name = field.getName();
-      if (!(field instanceof PsiEnumConstant) || used.contains(field) || name == null) {
+      if (!(field instanceof PsiEnumConstant) || used.contains(CompletionUtil.getOriginalOrSelf(field)) || name == null) {
         continue;
       }
       String prefix = "case ";
       String suffix = name + ":";
-      result.addElement(LookupElementBuilder.create(field, prefix + suffix).bold().withPresentableText(prefix).withTailText(suffix).withLookupString(name));
+      LookupElementBuilder caseConst = LookupElementBuilder
+        .create(field, prefix + suffix)
+        .bold()
+        .withPresentableText(prefix)
+        .withTailText(suffix)
+        .withLookupString(name);
+      result.addElement(new JavaCompletionContributor.IndentingDecorator(caseConst));
     }
   }
 

java/java-tests/testData/codeInsight/completion/keywords/noCaseInsideWhileInSwitch.java

@@ -0,0 +1,8 @@
+public class StructuredConfigKey {
+  {
+    switch (x) {
+      case 2:
+        while (true) <caret>
+    }
+  }
+}

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

@@ -0,0 +1,13 @@
+class A extends Base{
+  void foo(B b){
+    switch(b) {
+        case FOO:
+          GOO<caret>
+    }
+  }
+}
+
+enum B{
+  FOO, BAR, GOO
+}
+

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

@@ -0,0 +1,13 @@
+class A extends Base{
+  void foo(B b){
+    switch(b) {
+        case FOO:
+        case GOO:<caret>
+    }
+  }
+}
+
+enum B{
+  FOO, BAR, GOO
+}
+

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

@@ -2,7 +2,7 @@ class A extends Base{
   void foo(){
     B x = null;
     switch(x){
-      case GOO:<caret>
+        case GOO:<caret>
     }
   }
 }

java/java-tests/testSrc/com/intellij/codeInsight/completion/KeywordCompletionTest.java

@@ -126,6 +126,7 @@ public class KeywordCompletionTest extends LightCompletionTestCase {
   public void testFinalAfterParameterAnno() throws Exception { doTest(2, "final", "float", "class"); }
   public void testFinalAfterParameterAnno2() throws Exception { doTest(2, "final", "float", "class"); }
   public void testFinalAfterCase() { doTest(3, "final", "float", "class"); }
+  public void testNoCaseInsideWhileInSwitch() { doTest(0, "case", "default"); }
   public void testFinalInCatch() { doTest(1, "final"); }
   public void testFinalInIncompleteCatch() { doTest(1, "final"); }
   public void testFinalInTryWithResources() throws Exception { doTest(1, "final", "float", "class"); }

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

@@ -291,6 +291,7 @@ public class NormalCompletionTest extends LightFixtureCompletionTestCase {
   }
 
   public void testSwitchCaseWithEnumConstant() { doTest() }
+  public void testSecondSwitchCaseWithEnumConstant() { doTest() }
 
   public void testMethodInAnnotation() throws Exception {
     configureByFile("Annotation.java");