Work around an Eclipse bug where the upper bound of a type variable like <T extends Comparable<T>> can show up as being T, leading to infinite recursion. MoreTypes isn't tested with Eclipse at the moment, unfortunately, but the bug showed up in AutoValue's CompileWithEclipseTest when I tried to add a <T extends Comparable<T>> to AutoValueTest.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=83609722
diff --git a/common/src/main/java/com/google/auto/common/MoreTypes.java b/common/src/main/java/com/google/auto/common/MoreTypes.java
index 274d11c..5a5423a 100644
--- a/common/src/main/java/com/google/auto/common/MoreTypes.java
+++ b/common/src/main/java/com/google/auto/common/MoreTypes.java
@@ -131,8 +131,9 @@
DeclaredType b = (DeclaredType) p.type;
Element aElement = a.asElement();
Element bElement = b.asElement();
- ComparedElements comparedElements = new ComparedElements(aElement, bElement);
- if (p.visiting.contains(comparedElements)) {
+ Set<ComparedElements> newVisiting = visitingSetPlus(p.visiting, aElement, bElement);
+ if (newVisiting.equals(p.visiting)) {
+ // We're already visiting this pair of elements.
// This can happen for example with Enum in Enum<E extends Enum<E>>. Return a
// provisional true value since if the Elements are not in fact equal the original
// visitor of Enum will discover that. We have to check both Elements being compared
@@ -140,8 +141,6 @@
// differs at exactly this point.
return true;
}
- Set<ComparedElements> newVisiting = new HashSet<ComparedElements>(p.visiting);
- newVisiting.add(comparedElements);
return aElement.equals(bElement)
&& equal(a.getEnclosingType(), a.getEnclosingType(), newVisiting)
&& equalLists(a.getTypeArguments(), b.getTypeArguments(), newVisiting);
@@ -171,8 +170,17 @@
public Boolean visitTypeVariable(TypeVariable a, EqualVisitorParam p) {
if (p.type.getKind().equals(TYPEVAR)) {
TypeVariable b = (TypeVariable) p.type;
- return equal(a.getUpperBound(), b.getUpperBound(), p.visiting)
- && equal(a.getLowerBound(), b.getLowerBound(), p.visiting);
+ Element aElement = a.asElement();
+ Element bElement = b.asElement();
+ Set<ComparedElements> newVisiting = visitingSetPlus(p.visiting, aElement, bElement);
+ if (newVisiting.equals(p.visiting)) {
+ // We're already visiting this pair of elements.
+ // This can happen with our friend Eclipse when looking at <T extends Comparable<T>>.
+ // It incorrectly reports the upper bound of T as T itself.
+ return true;
+ }
+ return equal(a.getUpperBound(), b.getUpperBound(), newVisiting)
+ && equal(a.getLowerBound(), b.getLowerBound(), newVisiting);
}
return false;
}
@@ -191,6 +199,14 @@
public Boolean visitUnknown(TypeMirror a, EqualVisitorParam p) {
throw new UnsupportedOperationException();
}
+
+ private Set<ComparedElements> visitingSetPlus(
+ Set<ComparedElements> visiting, Element a, Element b) {
+ ComparedElements comparedElements = new ComparedElements(a, b);
+ Set<ComparedElements> newVisiting = new HashSet<ComparedElements>(visiting);
+ newVisiting.add(comparedElements);
+ return newVisiting;
+ }
};
private static final Class<?> INTERSECTION_TYPE;
