fix and clarify "Cyclic class dependency" inspection warning

plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/InspectionGadgetsBundle.properties

@@ -1510,6 +1510,8 @@ class.with.too.many.transitive.dependencies.max.option=Maximum number of transit
 class.with.too.many.transitive.dependents.max.option=Maximum number of transitive dependents
 cyclic.class.dependency.display.name=Cyclic class dependency
 cyclic.class.dependency.problem.descriptor=Class ''{0}'' is cyclically dependent on {1} other classes
+cyclic.class.dependency.1.problem.descriptor=Class ''{0}'' is cyclically dependent on class ''{1}''
+cyclic.class.dependency.2.problem.descriptor=Class ''{0}'' is cyclically dependent on classes ''{1}'' and ''{2}''
 cyclic.package.dependency.display.name=Cyclic package dependency
 cyclic.package.dependency.problem.descriptor=Package ''{0}'' is cyclically dependent on {1} other packages
 class.unconnected.to.package.display.name=Class independent of its package

plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/dependency/CyclicClassDependencyInspection.java

@@ -16,17 +16,19 @@
 package com.siyeh.ig.dependency;
 
 import com.intellij.analysis.AnalysisScope;
-import com.intellij.codeInspection.CommonProblemDescriptor;
-import com.intellij.codeInspection.GlobalInspectionContext;
-import com.intellij.codeInspection.InspectionManager;
+import com.intellij.codeInspection.*;
 import com.intellij.codeInspection.reference.RefClass;
 import com.intellij.codeInspection.reference.RefEntity;
+import com.intellij.codeInspection.util.RefEntityAlphabeticalComparator;
+import com.intellij.psi.PsiAnonymousClass;
 import com.intellij.psi.PsiClass;
+import com.intellij.psi.PsiElement;
 import com.siyeh.InspectionGadgetsBundle;
 import com.siyeh.ig.BaseGlobalInspection;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.Arrays;
 import java.util.HashSet;
 import java.util.Set;
 
@@ -35,8 +37,7 @@ public class CyclicClassDependencyInspection extends BaseGlobalInspection {
   @NotNull
   @Override
   public String getDisplayName() {
-    return InspectionGadgetsBundle.message(
-      "cyclic.class.dependency.display.name");
+    return InspectionGadgetsBundle.message("cyclic.class.dependency.display.name");
   }
 
   @Override
@@ -54,22 +55,42 @@ public class CyclicClassDependencyInspection extends BaseGlobalInspection {
     if (aClass == null || aClass.getContainingClass() != null) {
       return null;
     }
-    final Set<RefClass> dependencies =
-      DependencyUtils.calculateTransitiveDependenciesForClass(refClass);
-    final Set<RefClass> dependents =
-      DependencyUtils.calculateTransitiveDependentsForClass(refClass);
-    final Set<RefClass> mutualDependents =
-      new HashSet<RefClass>(dependencies);
+    final Set<RefClass> dependencies = DependencyUtils.calculateTransitiveDependenciesForClass(refClass);
+    final Set<RefClass> dependents = DependencyUtils.calculateTransitiveDependentsForClass(refClass);
+    final Set<RefClass> mutualDependents = new HashSet<RefClass>(dependencies);
     mutualDependents.retainAll(dependents);
     final int numMutualDependents = mutualDependents.size();
-    if (numMutualDependents <= 1) {
+    if (numMutualDependents == 0) {
       return null;
     }
-    final String errorString = InspectionGadgetsBundle.message(
-      "cyclic.class.dependency.problem.descriptor",
-      refEntity.getName(), Integer.valueOf(numMutualDependents - 1));
+    final String errorString;
+    if (numMutualDependents == 1) {
+      final RefClass[] classes = mutualDependents.toArray(new RefClass[1]);
+      errorString = InspectionGadgetsBundle.message("cyclic.class.dependency.1.problem.descriptor",
+                                                    refEntity.getName(), classes[0].getExternalName());
+    }
+    else if (numMutualDependents == 2) {
+      final RefClass[] classes = mutualDependents.toArray(new RefClass[2]);
+      Arrays.sort(classes, RefEntityAlphabeticalComparator.getInstance());
+      errorString = InspectionGadgetsBundle.message("cyclic.class.dependency.2.problem.descriptor",
+                                                    refEntity.getName(), classes[0].getExternalName(), classes[1].getExternalName());
+    }
+    else {
+      errorString = InspectionGadgetsBundle.message("cyclic.class.dependency.problem.descriptor",
+                                                    refEntity.getName(), Integer.valueOf(numMutualDependents));
+    }
+    final PsiElement anchor;
+    if (aClass instanceof PsiAnonymousClass) {
+      final PsiAnonymousClass anonymousClass = (PsiAnonymousClass)aClass;
+      anchor = anonymousClass.getBaseClassReference();
+    }
+    else {
+      anchor = aClass.getNameIdentifier();
+      if (anchor == null) return null;
+    }
     return new CommonProblemDescriptor[]{
-      inspectionManager.createProblemDescriptor(errorString)
+      inspectionManager.createProblemDescriptor(anchor, errorString, (LocalQuickFix)null,
+                                                ProblemHighlightType.GENERIC_ERROR_OR_WARNING, false)
     };
   }
 }

plugins/InspectionGadgets/test/com/siyeh/igtest/abstraction/cyclic_class_dependency/expected.xml

@@ -0,0 +1,44 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<problems>
+  <problem>
+    <file>Cyclic.java</file>
+    <line>9</line>
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Cyclic class dependency</problem_class>
+    <description>Class 'anonymous (java.lang.Object)' is cyclically dependent on 3 other classes</description>
+  </problem>
+
+  <problem>
+    <file>Cyclic.java</file>
+    <line>17</line>
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Cyclic class dependency</problem_class>
+    <description>Class 'Base' is cyclically dependent on classes 'com.siyeh.igtest.abstraction.cyclic_class_dependency.src.Cyclic' and 'com.siyeh.igtest.abstraction.cyclic_class_dependency.src.Top'</description>
+  </problem>
+
+  <problem>
+    <file>Cyclic.java</file>
+    <line>29</line>
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Cyclic class dependency</problem_class>
+    <description>Class 'Coffee' is cyclically dependent on class 'com.siyeh.igtest.abstraction.cyclic_class_dependency.src.FiveOClock'</description>
+  </problem>
+
+  <problem>
+    <file>Cyclic.java</file>
+    <line>25</line>
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Cyclic class dependency</problem_class>
+    <description>Class 'FiveOClock' is cyclically dependent on class 'com.siyeh.igtest.abstraction.cyclic_class_dependency.src.Coffee'</description>
+  </problem>
+
+  <problem>
+    <file>Cyclic.java</file>
+    <line>22</line>
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Cyclic class dependency</problem_class>
+    <description>Class 'Top' is cyclically dependent on classes 'com.siyeh.igtest.abstraction.cyclic_class_dependency.src.Base' and 'com.siyeh.igtest.abstraction.cyclic_class_dependency.src.Cyclic'</description>
+  </problem>
+
+  <problem>
+    <file>Cyclic.java</file>
+    <line>6</line>
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Cyclic class dependency</problem_class>
+    <description>Class 'Cyclic' is cyclically dependent on classes 'com.siyeh.igtest.abstraction.cyclic_class_dependency.src.Base' and 'com.siyeh.igtest.abstraction.cyclic_class_dependency.src.Top'</description>
+  </problem>
+</problems>

plugins/InspectionGadgets/test/com/siyeh/igtest/abstraction/cyclic_class_dependency/src/Cyclic.java

@@ -0,0 +1,29 @@
+package com.siyeh.igtest.abstraction.cyclic_class_dependency.src;
+
+/**
+ * @author Bas Leijdekkers
+ */
+public class Cyclic extends Base {
+
+  Cyclic() {
+    new Object() {{
+      foo();
+    }};
+  }
+
+  void foo() {}
+
+}
+class Base {
+  void a() {
+    Top.m();
+  }
+}
+class Top extends Cyclic {
+  public static void m() {}
+}
+interface FiveOClock {
+  void m(Coffee c);
+
+}
+interface Coffee extends FiveOClock {}

plugins/InspectionGadgets/testsrc/com/siyeh/ig/abstraction/CyclicClassDependencyInspectionTest.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2000-2013 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.siyeh.ig.abstraction;
+
+import com.siyeh.ig.IGInspectionTestCase;
+import com.siyeh.ig.dependency.CyclicClassDependencyInspection;
+
+/**
+ * @author Bas Leijdekkers
+ */
+public class CyclicClassDependencyInspectionTest extends IGInspectionTestCase {
+
+  public void test() {
+    doTest("com/siyeh/igtest/abstraction/cyclic_class_dependency", new CyclicClassDependencyInspection());
+  }
+}