clojure.test 抛出？不在 repl 中工作

Question

根据 clojure.test 源代码中的文档字符串，我在 repl 中发出以下内容：

(use 'clojure.test)
(is (thrown? ArithmeticException (/ 1 0)))

以及其他变体，例如将 ArithmeticException 替换为 java.lang.ArithmeticException。然而，异常从未被 clojure.test 捕获，而是一直冒到顶部：

> #error {  :cause "Divide by zero"  :via  [{:type java.lang.ArithmeticException    :message "Divide by zero"    :at
> [clojure.lang.Numbers divide "Numbers.java" 158]}]  :trace 
> [[clojure.lang.Numbers divide "Numbers.java" 158]  
> [clojure.lang.Numbers divide "Numbers.java" 3808]   [api.core$eval1305
> invokeStatic "form-init8750388124499546857.clj" 1]  
> [api.core$eval1305 invoke "form-init8750388124499546857.clj" 1]  
> [clojure.lang.Compiler eval "Compiler.java" 6927]  
> [clojure.lang.Compiler eval "Compiler.java" 6890]   [clojure.core$eval
> invokeStatic "core.clj" 3105]   [clojure.core$eval invoke "core.clj"
> 3101]   [clojure.main$repl$read_eval_print__7408$fn__7411 invoke
> "main.clj" 240]   [clojure.main$repl$read_eval_print__7408 invoke
> "main.clj" 240]   [clojure.main$repl$fn__7417 invoke "main.clj" 258]  
> [clojure.main$repl invokeStatic "main.clj" 258]   [clojure.main$repl
> doInvoke "main.clj" 174]   [clojure.lang.RestFn invoke "RestFn.java"
> 1523]  
> [clojure.tools.nrepl.middleware.interruptible_eval$evaluate$fn__667
> invoke "interruptible_eval.clj" 87]   [clojure.lang.AFn applyToHelper
> "AFn.java" 152]   [clojure.lang.AFn applyTo "AFn.java" 144]  
> [clojure.core$apply invokeStatic "core.clj" 646]  
> [clojure.core$with_bindings_STAR_ invokeStatic "core.clj" 1881]  
> [clojure.core$with_bindings_STAR_ doInvoke "core.clj" 1881]  
> [clojure.lang.RestFn invoke "RestFn.java" 425]  
> [clojure.tools.nrepl.middleware.interruptible_eval$evaluate
> invokeStatic "interruptible_eval.clj" 85]  
> [clojure.tools.nrepl.middleware.interruptible_eval$evaluate invoke
> "interruptible_eval.clj" 55]  
> [clojure.tools.nrepl.middleware.interruptible_eval$interruptible_eval$fn__712$fn__715
> invoke "interruptible_eval.clj" 222]  
> [clojure.tools.nrepl.middleware.interruptible_eval$run_next$fn__707
> invoke "interruptible_eval.clj" 190]   [clojure.lang.AFn run
> "AFn.java" 22]   [java.util.concurrent.ThreadPoolExecutor runWorker
> "ThreadPoolExecutor.java" 1142]  
> [java.util.concurrent.ThreadPoolExecutor$Worker run
> "ThreadPoolExecutor.java" 617]   [java.lang.Thread run "Thread.java"
> 745]]}

可能是什么？ clojure.test 中的其他内容确实在 repl 中按预期工作。

版本信息：

Leiningen 2.7.1 on Java 1.8.0_101 Java HotSpot(TM) 64-Bit Server VM

> nREPL server started on port 44025 on host 127.0.0.1 -
> nrepl://127.0.0.1:44025 REPL-y 0.3.7, nREPL 0.2.12 Clojure 1.8.0 Java
> HotSpot(TM) 64-Bit Server VM 1.8.0_101-b13

Answer 1

在(clojure.test/deftest...)

中使用it/wrap

假设：

(require '[clojure.test :as t])

通过示例

(t/deftest a 
  (t/testing "a test" 
    (t/is (thrown? ArithmeticException (/ 1 0)))))

(a)
nil

失败示例

(t/deftest a 
  (t/testing "a test" 
    (t/is (thrown? NullPointerException (/ 1 0)))))

(a)
; ERROR in (a) (Numbers.java:158)
; a test
; expected: (thrown? NullPointerException (/ 1 0))
; actual: java.lang.ArithmeticException: Divide by zero

您还可以使用 t/run-tests 获得 summary/stats

或者你似乎可以像这样直接使用 t/test-var

(t/test-var (t/is (thrown? ArithmeticException (/ 1 0))))
nil

Answer 2

您可能还对 throws? 宏感兴趣 from the Tupelo library。它更通用，比 clojure.test 中的 thrown? 子句更易于使用。请注意 clojure.test 中的 thrown? 不是正常的 Clojure 函数或宏，但是是仅在 is 宏中识别的自定义表达式。

tupelo.test/throws? 宏是一个普通的 Clojure 宏，可以在任何地方使用。

throws? 应单独使用，不应包含在 is 语句中。请注意，throws? 始终 returns true 或 false，可用于进一步处理。

> lein repl
user=> (use 'tupelo.test)
user=> (throws?  (/ 1 0))
true    ; <= return value

user=> (throws? Exception (/ 1 0))
true    ; <= return value

user=> (throws? ArithmeticException (/ 1 0))
true    ; <= return value

如果表达式没有抛出异常，或者抛出不同类型的异常，那么 throws? 将通过 (clojure.test/is false) 注册失败的测试，并且还将 return false:

user=> (throws? NullPointerException (/ 1 0))
FAIL in () (form-init2868942318552383212.clj:1)
expected: (try (/ 1 0) false (catch NullPointerException t1__13775__auto__ true) (catch java.lang.Throwable t2__13776__auto__ false))
  actual: false
false   ; <= return value

clj.core=> (throws? ArithmeticException (+ 1 0))
FAIL in () (form-init4299343763551622058.clj:1)
expected: (try (+ 1 0) false (catch ArithmeticException t1__13761__auto__ true) (catch java.lang.Throwable t2__13762__auto__ false))
  actual: false
false    ; <= return value

clj.core=> (throws? (+ 1 0))
FAIL in () (form-init4299343763551622058.clj:1)
expected: (try (+ 1 0) false (catch java.lang.Throwable t3__13763__auto__ true))
  actual: false
false    ; <= return value

throws? 的典型用法由 tupelo.core 自己的单元测试说明：

(ns test.tupelo.core
  (:use clojure.test tupelo.test )
  (:require [tupelo.core :as t] ))
(t/refer-tupelo)

(deftest t-grab
  (let [map1  {:a 1 :b 2}]
    (is= 1    (grab :a map1))
    (is= 2    (grab :b map1))
    (throws?  (grab :c map1)) ))

clojure.test 抛出？不在 repl 中工作

clojure.test throws? not working in the repl

clojure

leiningen