Java: Add toString consistency query

java/ql/consistency-queries/toString.ql

@@ -0,0 +1,33 @@
+import java
+
+string topToString(Top t) {
+  result = t.toString()
+  or
+  // TypeBound doesn't extend Top (but probably should)
+  result = t.(TypeBound).toString()
+  or
+  // XMLLocatable doesn't extend Top (but probably should)
+  result = t.(XMLLocatable).toString()
+  or
+  // Java #142
+  t instanceof FieldDeclaration and not exists(t.toString()) and result = "<FieldDeclaration>"
+  or
+  // Java #143
+  t instanceof Javadoc and not exists(t.toString()) and result = "<Javadoc>"
+  or
+  // Java #144
+  t instanceof ReflectiveAccessAnnotation and not exists(t.toString()) and result = "<ReflectiveAccessAnnotation>"
+}
+
+string not1ToString() {
+  exists(Top t | count(topToString(t)) != 1 and result = "Top which doesn't have exactly 1 toString: " + concat(t.getAQlClass(), ", "))
+  or
+  exists(Location l | count(l.toString()) != 1 and result = "Location which doesn't have exactly 1 toString: " + concat(l.getAQlClass(), ", "))
+  or
+  exists(Module m | count(m.toString()) != 1 and result = "Module which doesn't have exactly 1 toString: " + concat(m.getAQlClass(), ", "))
+  or
+  exists(Directive d | count(d.toString()) != 1 and result = "Directive which doesn't have exactly 1 toString: " + concat(d.getAQlClass(), ", "))
+}
+
+select not1ToString()
+