[nongnu] elpa/buttercup 7526198 029/340: Spies: :and-throw-error

[ELPA Syncer]

branch: elpa/buttercup
commit 752619812cd9f0d4d954cc31a87e46607a72e3dc
Author: Jorgen Schaefer <contact@jorgenschaefer.de>
Commit: Jorgen Schaefer <contact@jorgenschaefer.de>

    Spies: :and-throw-error
---
 README.md         | 21 +++++++++++++++++++++
 buttercup-test.el |  9 +++++++++
 buttercup.el      |  4 ++++
 3 files changed, 34 insertions(+)

diff --git a/README.md b/README.md
index 8eaad06..03c3f87 100644
--- a/README.md
+++ b/README.md
@@ -431,6 +431,27 @@ function.
       (expect fetched-bar :to-equal 1001))))
 ```
 
+### Spies: `:and-throw-error`
+
+With the keyword argument `:and-throw-error`, all calls to the spy
+will `signal` the specified value as an error.
+
+```Lisp
+(describe "A spy, when configured to throw an error"
+  (let (bar set-bar get-bar fetched-bar)
+    (before-each
+      (fset 'set-bar (lambda (val)
+                       (setq bar val)))
+      (fset 'get-bar (lambda ()
+                       bar))
+
+      (spy-on 'get-bar :and-throw-error 'error))
+
+    (it "throws the error"
+      (expect (lambda () (get-bar))
+              :to-throw 'error))))
+```
+
 
 ## Test Runners
 
diff --git a/buttercup-test.el b/buttercup-test.el
index 3fc2119..fc8d10c 100644
--- a/buttercup-test.el
+++ b/buttercup-test.el
@@ -419,3 +419,12 @@
     (expect (test-function 2 3)
             :to-equal
             1001)))
+
+(describe "The :and-throw-error keyword functionality"
+  (before-each
+    (spy-on 'test-function :and-throw-error 'error))
+
+  (it "throws an error when called"
+    (expect (lambda () (test-function 1 2))
+            :to-throw
+            'error "Stubbed error")))
diff --git a/buttercup.el b/buttercup.el
index 83e3c6e..d02bc07 100644
--- a/buttercup.el
+++ b/buttercup.el
@@ -384,6 +384,10 @@ A disabled spec is not run."
       (setq new-value (lambda (&rest args)
                         (buttercup--spy-add-call new-value args)
                         (apply arg args))))
+     ((eq keyword :and-throw-error)
+      (setq new-value (lambda (&rest args)
+                        (buttercup--spy-add-call new-value args)
+                        (signal arg "Stubbed error"))))
      ((not keyword)
       (setq new-value (lambda (&rest args)
                         (buttercup--spy-add-call new-value args)