field naming convention: retrieve mutability from external annotations

IDEA-187941

plugins/InspectionGadgets/src/com/siyeh/ig/naming/ConstantWithMutableFieldTypeNamingConvention.java

@@ -15,10 +15,10 @@
  */
 package com.siyeh.ig.naming;
 
+import com.intellij.codeInspection.dataFlow.Mutability;
 import com.intellij.codeInspection.naming.NamingConvention;
 import com.intellij.codeInspection.naming.NamingConventionBean;
-import com.intellij.psi.PsiField;
-import com.intellij.psi.PsiModifier;
+import com.intellij.psi.*;
 import com.siyeh.InspectionGadgetsBundle;
 import com.siyeh.ig.psiutils.ClassUtils;
 
@@ -48,6 +48,18 @@ public class ConstantWithMutableFieldTypeNamingConvention extends NamingConventi
 
   @Override
   public boolean isApplicable(PsiField field) {
-    return field.hasModifierProperty(PsiModifier.STATIC) && field.hasModifierProperty(PsiModifier.FINAL) && !ClassUtils.isImmutable(field.getType());
+    if (field.hasModifierProperty(PsiModifier.STATIC) && field.hasModifierProperty(PsiModifier.FINAL)) {
+      PsiExpression initializer = field.getInitializer();
+      if (initializer instanceof PsiCallExpression) {
+        PsiMethod method = ((PsiCallExpression)initializer).resolveMethod();
+        if (method != null && Mutability.getMutability(method).isUnmodifiable()) {
+          return false;
+        }
+      }
+      if (!ClassUtils.isImmutable(field.getType())) {
+        return true;
+      }
+    }
+    return false;
   }
 }

plugins/InspectionGadgets/test/com/siyeh/igtest/naming/field_naming_convention/ConstantWithMutableFieldTypeNamingConvention.java

@@ -0,0 +1,7 @@
+package com.siyeh.igtest.naming.constant_naming_convention;
+
+import java.util.*;
+
+class ConstantNamingConvention {
+  static final List<String> unmodifiableList = Collections.unmodifiableList(new ArrayList<>());
+}

plugins/InspectionGadgets/testsrc/com/siyeh/ig/naming/ConstantWithMutableFieldTypeNamingConventionInspectionTest.java

@@ -0,0 +1,40 @@
+// 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.siyeh.ig.naming;
+
+import com.intellij.codeInspection.InspectionProfileEntry;
+import com.intellij.openapi.projectRoots.Sdk;
+import com.intellij.testFramework.IdeaTestUtil;
+import com.intellij.testFramework.LightProjectDescriptor;
+import com.intellij.testFramework.PsiTestUtil;
+import com.intellij.testFramework.fixtures.DefaultLightProjectDescriptor;
+import com.siyeh.ig.LightInspectionTestCase;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public class ConstantWithMutableFieldTypeNamingConventionInspectionTest extends LightInspectionTestCase {
+
+  public void testConstantWithMutableFieldTypeNamingConvention() {
+    doTest();
+  }
+
+  @Nullable
+  @Override
+  protected InspectionProfileEntry getInspection() {
+    FieldNamingConventionInspection inspection = new FieldNamingConventionInspection();
+    inspection.setEnabled(true, new ConstantWithMutableFieldTypeNamingConvention().getShortName());
+    return inspection;
+  }
+  
+  private static final DefaultLightProjectDescriptor PROJECT_DESCRIPTOR = new DefaultLightProjectDescriptor() {
+    @Override
+    public Sdk getSdk() {
+      return PsiTestUtil.addJdkAnnotations(IdeaTestUtil.getMockJdk18());
+    }
+  };
+
+  @NotNull
+  @Override
+  protected LightProjectDescriptor getProjectDescriptor() {
+    return PROJECT_DESCRIPTOR;
+  }
+}