         }
 
         builder.serve(root: "root", with: [
-            ("config", v2Range),
-            ("foo", v1Range),
+            "config": v2Range,
+            "foo": v1Range,
         ])
         addDeps()
         let resolver1 = builder.create()
         _ = resolver1.solve(root: rootRef, pins: [])
 
         builder.serve(root: "root", with: [
-            ("foo", v1Range),
-            ("config", v2Range),
+            "foo": v1Range,
+            "config": v2Range,
         ])
         addDeps()
         let resolver2 = builder.create()


    func testConflict3() {
        builder.serve(root: "root", with: [
            ("foo", v1Range),
            ("config", v2Range),
        ])
        builder.serve("foo", at: v1, with: ["config": v1Range])
        builder.serve("config", at: v1)

            return XCTFail("Expected unresolvable graph.")
        }

        XCTAssertEqual(cause.description, "{foo 1.0.0..<2.0.0}")
    }
}

