NullPointerException from adzerk.boot-cljs.impl/handle-ex

[au-phiware]

I encountered a NullPointerException today:

                                       java.lang.Thread.run                  Thread.java:  748
         java.util.concurrent.ThreadPoolExecutor$Worker.run      ThreadPoolExecutor.java:  624
          java.util.concurrent.ThreadPoolExecutor.runWorker      ThreadPoolExecutor.java: 1149
                        java.util.concurrent.FutureTask.run              FutureTask.java:  266
                                                        ...                                   
                        clojure.core/binding-conveyor-fn/fn                     core.clj: 2022
                              adzerk.boot-cljs/compile-1/fn                boot_cljs.clj:  160
                                   adzerk.boot-cljs/compile                boot_cljs.clj:   72
                                          boot.pod/call-in*                      pod.clj:  413
                                                        ...                                   
org.projectodd.shimdandy.impl.ClojureRuntimeShimImpl.invoke  ClojureRuntimeShimImpl.java:  102
org.projectodd.shimdandy.impl.ClojureRuntimeShimImpl.invoke  ClojureRuntimeShimImpl.java:  109
                                                        ...                                   
                                          boot.pod/call-in*                      pod.clj:  410
                                      boot.pod/eval-fn-call                      pod.clj:  359
                                         clojure.core/apply                     core.clj:  657
                                                        ...                                   
                         adzerk.boot-cljs.impl/compile-cljs                     impl.clj:  163
                            adzerk.boot-cljs.impl/handle-ex                     impl.clj:  107
                 adzerk.boot-cljs.impl/escape-format-string                     impl.clj:   64
                                     clojure.string/replace                   string.clj:  101
java.lang.NullPointerException: 
    clojure.lang.ExceptionInfo: 
    file: "/tmp/boot.user5150054472668965626.clj"
    line: 49

I figure that ensure-ends-in-newline should always return a string even if it is "\n"?