Test.swift

import ObjectMapper

struct Test: Mappable {
    let name: String

    init?(_ map: Map) {
        name = map["name"].valueOrFail()

        if !map.isValid {
            return nil
        }
    }

    func mapping(map: Map) {
    }
}

TestTest.swift

import XCTest
import ObjectMapper

class TestTest: XCTestCase {
    func testParseJson() {
        // works
        let validJsonString = "{ \"name\": \"test\" }"
        Mapper<Test>().map(validJsonString)

        // EXEC_BAD_ACCESS
        let invalidJsonString = "{ \"NOT name\": \"test\" }"
        Mapper<Test>().map(invalidJsonString)
    }
}