use module to determine language level (IDEA-151620)

java/java-psi-api/src/com/intellij/psi/PsiResolveHelper.java

@@ -19,6 +19,7 @@ import com.intellij.openapi.components.ServiceManager;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.RecursionGuard;
 import com.intellij.openapi.util.RecursionManager;
+import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.pom.java.LanguageLevel;
 import com.intellij.psi.impl.source.resolve.ParameterTypeInferencePolicy;
 import com.intellij.psi.infos.CandidateInfo;
@@ -169,4 +170,8 @@ public interface PsiResolveHelper {
                                           PsiType arg,
                                           boolean isContraVariantPosition,
                                           LanguageLevel languageLevel);
+
+  @NotNull
+  LanguageLevel getEffectiveLanguageLevel(@Nullable VirtualFile virtualFile);
+
 }

java/java-psi-api/src/com/intellij/psi/util/PsiUtil.java

@@ -970,7 +970,8 @@ public final class PsiUtil extends PsiUtilCore {
       }
     }
 
-    return getLanguageLevel(element.getProject());
+    PsiResolveHelper instance = PsiResolveHelper.SERVICE.getInstance(element.getProject());
+    return instance != null ? instance.getEffectiveLanguageLevel(getVirtualFile(file)) : LanguageLevel.HIGHEST;
   }
 
   @NotNull

java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/PsiResolveHelperImpl.java

@@ -16,8 +16,10 @@
 package com.intellij.psi.impl.source.resolve;
 
 import com.intellij.openapi.diagnostic.Logger;
+import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.pom.java.LanguageLevel;
 import com.intellij.psi.*;
+import com.intellij.psi.impl.JavaPsiImplementationHelper;
 import com.intellij.psi.impl.source.resolve.graphInference.PsiGraphInferenceHelper;
 import com.intellij.psi.infos.CandidateInfo;
 import com.intellij.psi.scope.MethodProcessorSetupFailedException;
@@ -208,6 +210,12 @@ public class PsiResolveHelperImpl implements PsiResolveHelper {
       .getSubstitutionForTypeParameter(typeParam, param, arg, isContraVariantPosition, languageLevel);
   }
 
+  @NotNull
+  @Override
+  public LanguageLevel getEffectiveLanguageLevel(@Nullable VirtualFile virtualFile) {
+    return JavaPsiImplementationHelper.getInstance(myManager.getProject()).getEffectiveLanguageLevel(virtualFile);
+  }
+
   @NotNull
   public PsiInferenceHelper getInferenceHelper(@NotNull LanguageLevel languageLevel) {
     if (languageLevel.isAtLeast(LanguageLevel.JDK_1_8)) {