diff --git a/refaster-support/src/main/java/tech/picnic/errorprone/refaster/matchers/IsEmpty.java b/refaster-support/src/main/java/tech/picnic/errorprone/refaster/matchers/IsEmpty.java
index 7cbb8560e01..c21a6fd204c 100644
--- a/refaster-support/src/main/java/tech/picnic/errorprone/refaster/matchers/IsEmpty.java
+++ b/refaster-support/src/main/java/tech/picnic/errorprone/refaster/matchers/IsEmpty.java
@@ -1,5 +1,6 @@
 package tech.picnic.errorprone.refaster.matchers;
 
+import static com.google.common.base.Verify.verify;
 import static com.google.errorprone.matchers.FieldMatchers.staticField;
 import static com.google.errorprone.matchers.Matchers.allOf;
 import static com.google.errorprone.matchers.Matchers.anyOf;
@@ -47,6 +48,7 @@ public final class IsEmpty implements Matcher<ExpressionTree> {
   private static final long serialVersionUID = 1L;
   private static final Pattern EMPTY_INSTANCE_FACTORY_METHOD_PATTERN = Pattern.compile("empty.*");
   private static final Matcher<Tree> PRIMITIVE_TYPE = isPrimitiveType();
+  // XXX: Extend this list to include additional JDK collection types with a public constructor.
   private static final Matcher<ExpressionTree> MUTABLE_COLLECTION_TYPE =
       anyOf(
           isSameType(ArrayList.class),
@@ -117,7 +119,8 @@ private boolean isEmptyCollectionConstructor(ExpressionTree tree, VisitorState s
      * This looks like a copy constructor, in which case the resultant collection is empty if its
      * argument is.
      */
-    return arguments.size() == 1 && matches(arguments.get(0), state);
+    verify(arguments.size() == 1, "Unexpected %s-ary constructor", arguments.size());
+    return matches(arguments.get(0), state);
   }
 
   private static boolean isEmptyArrayCreation(ExpressionTree tree) {
diff --git a/refaster-support/src/test/java/tech/picnic/errorprone/refaster/matchers/IsEmptyTest.java b/refaster-support/src/test/java/tech/picnic/errorprone/refaster/matchers/IsEmptyTest.java
index 46a71800e3a..705d7b5f994 100644
--- a/refaster-support/src/test/java/tech/picnic/errorprone/refaster/matchers/IsEmptyTest.java
+++ b/refaster-support/src/test/java/tech/picnic/errorprone/refaster/matchers/IsEmptyTest.java
@@ -24,6 +24,7 @@ void matches() {
             "import java.util.LinkedList;",
             "import java.util.List;",
             "import java.util.Map;",
+            "import java.util.Random;",
             "import java.util.Set;",
             "import java.util.Stack;",
             "import java.util.Vector;",
@@ -49,47 +50,51 @@ void matches() {
             "    return new int[][] {{0}};",
             "  }",
             "",
-            "  List<Integer> negative5() {",
+            "  Random negative5() {",
+            "    return new Random();",
+            "  }",
+            "",
+            "  List<Integer> negative6() {",
             "    return new ArrayList<>(ImmutableList.of(1));",
             "  }",
             "",
-            "  Map<Integer, Integer> negative6() {",
+            "  Map<Integer, Integer> negative7() {",
             "    return new HashMap<>(ImmutableMap.of(1, 2));",
             "  }",
             "",
-            "  Map<Integer, Integer> negative7() {",
+            "  Map<Integer, Integer> negative8() {",
             "    return new LinkedHashMap<>(ImmutableMap.of(1, 2));",
             "  }",
             "",
-            "  ImmutableList<Integer> negative8() {",
+            "  ImmutableList<Integer> negative9() {",
             "    return ImmutableList.of(1);",
             "  }",
             "",
-            "  ImmutableSet<Integer> negative9() {",
+            "  ImmutableSet<Integer> negative10() {",
             "    return ImmutableSet.of(1);",
             "  }",
             "",
-            "  ImmutableMap<Integer, Integer> negative10() {",
+            "  ImmutableMap<Integer, Integer> negative11() {",
             "    return ImmutableMap.of(1, 2);",
             "  }",
             "",
-            "  ImmutableSetMultimap<Integer, Integer> negative11() {",
+            "  ImmutableSetMultimap<Integer, Integer> negative12() {",
             "    return ImmutableSetMultimap.of(1, 2);",
             "  }",
             "",
-            "  List<Integer> negative12() {",
+            "  List<Integer> negative13() {",
             "    return List.of(1);",
             "  }",
             "",
-            "  Map<Integer, Integer> negative13() {",
+            "  Map<Integer, Integer> negative14() {",
             "    return Map.of(1, 2);",
             "  }",
             "",
-            "  Set<Integer> negative14() {",
+            "  Set<Integer> negative15() {",
             "    return Set.of(1);",
             "  }",
             "",
-            "  Stream<Integer> negative15() {",
+            "  Stream<Integer> negative16() {",
             "    return Stream.of(1);",
             "  }",
             "",