[btree_damage_visitor] Introduce a DamagedKeys matcher in the tests.

persistent-data/data-structures/btree_damage_visitor.h

@@ -18,11 +18,6 @@ namespace persistent_data {
 				  desc_(desc) {
 			}
 
-			// FIXME: Write a matcher instead.  Does _not_ compare the descriptions
-			bool operator ==(damage const &rhs) const {
-				return (lost_keys_ == rhs.lost_keys_);
-			}
-
 			range<uint64_t> lost_keys_;
 			std::string desc_;
 		};

unit-tests/btree_damage_visitor_t.cc

@@ -225,6 +225,10 @@ namespace {
 
 	//----------------------------------
 
+	MATCHER_P(DamagedKeys, keys, "") {
+		return arg.lost_keys_ == keys;
+	}
+
 	class value_visitor_mock {
 	public:
 		MOCK_METHOD1(visit, void(thing const &));
@@ -270,7 +274,7 @@ namespace {
 		}
 
 		void expect_damage(unsigned level, range<uint64_t> keys) {
-			EXPECT_CALL(damage_visitor_, visit(Eq(damage(keys, "foo")))).Times(1);
+			EXPECT_CALL(damage_visitor_, visit(DamagedKeys(keys))).Times(1);
 		}
 
 		//--------------------------------