when inferring purity, honor class initializers (IDEA-CR-15144)

java/java-tests/testSrc/com/intellij/codeInspection/PurityInferenceFromSourceTest.groovy

@@ -163,6 +163,55 @@ public Foo() {
     """
   }
 
+  void "test anonymous class initializer"() {
+    assertPure false, """
+    Object smth() {
+        return new I(){{ created++; }};
+    }
+
+    private static int created = 0;
+    
+    interface I {}
+    """
+  }
+
+  void "test simple anonymous class creation"() {
+    assertPure true, """
+    Object smth() {
+        return new I(){};
+    }
+    
+    interface I {}
+    """
+  }
+
+  void "test anonymous class with arguments"() {
+    assertPure false, """
+    Object smth() {
+        return new I(unknown()){};
+    }
+    
+    class I {
+      I(int a) {}
+    }
+    """
+  }
+
+  void "test class with impure initializer creation"() {
+    assertPure false, """
+    Object smth() {
+        return new I(42);
+    }
+    
+    class I {
+      I(int answer) {}
+      {
+        launchMissiles();
+      }
+    }
+    """
+  }
+
   private void assertPure(boolean expected, String classBody) {
     def clazz = myFixture.addClass("final class Foo { $classBody }")
     assert !((PsiFileImpl) clazz.containingFile).contentsLoaded