From cbef19fae94ce912ff01d1c11cc334595e1f4772 Mon Sep 17 00:00:00 2001
From: Maximilian Tagher <feedback.tagher@gmail.com>
Date: Tue, 19 Nov 2019 23:11:13 -0800
Subject: [PATCH] [yesod-test] Add testModifySite

---
 yesod-test/ChangeLog.md     |  4 ++++
 yesod-test/Yesod/Test.hs    | 30 ++++++++++++++++++++++++------
 yesod-test/test/main.hs     |  2 +-
 yesod-test/yesod-test.cabal |  2 +-
 4 files changed, 30 insertions(+), 8 deletions(-)

diff --git a/yesod-test/ChangeLog.md b/yesod-test/ChangeLog.md
index ba1aa905..fe40bf15 100644
--- a/yesod-test/ChangeLog.md
+++ b/yesod-test/ChangeLog.md
@@ -1,5 +1,9 @@
 # ChangeLog for yesod-test
 
+## 1.6.8
+
+Add `testModifySite` function [#](https://github.com/yesodweb/yesod/pull/)
+
 ## 1.6.7
 
 Add `addBasicAuthHeader` function [#1632](https://github.com/yesodweb/yesod/pull/1632)
diff --git a/yesod-test/Yesod/Test.hs b/yesod-test/Yesod/Test.hs
index fcae9ffb..80b814f8 100644
--- a/yesod-test/Yesod/Test.hs
+++ b/yesod-test/Yesod/Test.hs
@@ -344,15 +344,33 @@ yesodSpecApp site getApp yspecs =
 yit :: String -> YesodExample site () -> YesodSpec site
 yit label example = tell [YesodSpecItem label example]
 
--- | Modifies the site ('yedSite') of the test
+-- | Modifies the site ('yedSite') of the test, and creates a new WAI app ('yedApp') for it.
 -- 
--- TODO documentation here
+-- yesod-test allows sending requests to your application to test that it handles them correctly.
+-- In rare cases, you may wish to modify that application in the middle of a test.
+-- This may be useful if you wish to, for example, test your application under a certain configuration,
+-- then change that configuration to see if your app responds differently.
 --
--- TODO @since
-testModifySite :: YesodDispatch site => (site -> site) -> Middleware -> YesodExample site ()
-testModifySite newSiteFn middleware = do
+-- ==== __Examples__
+--
+-- > post SendEmailR
+-- > -- Assert email not created in database
+-- > testModifySite (\site -> pure (site { siteSettingsStoreEmail = True }, id))
+-- > post SendEmailR
+-- > -- Assert email created in database
+--
+-- > testModifySite (\site -> do
+-- >   middleware <- makeLogware site
+-- >   pure (site { appRedisConnection = Nothing }, middleware)
+-- > )
+--
+-- @since 1.6.8
+testModifySite :: YesodDispatch site
+               => (site -> IO (site, Middleware)) -- ^ A function from the existing site, to a new site and middleware for a WAI app.
+               -> YesodExample site ()
+testModifySite newSiteFn = do
   currentSite <- getTestYesod 
-  let newSite = newSiteFn currentSite
+  (newSite, middleware) <- liftIO $ newSiteFn currentSite
   app <- liftIO $ toWaiAppPlain newSite
   modifySIO $ \yed -> yed { yedSite = newSite, yedApp = middleware app }
 
diff --git a/yesod-test/test/main.hs b/yesod-test/test/main.hs
index 57a93c17..f0f5b8e4 100644
--- a/yesod-test/test/main.hs
+++ b/yesod-test/test/main.hs
@@ -453,7 +453,7 @@ main = hspec $ do
         yit "can change site value" $ do
             get ("/get-integer" :: Text)
             bodyContains "0"
-            testModifySite (\site -> site { routedAppInteger = 1 }) id
+            testModifySite (\site -> pure (site { routedAppInteger = 1 }, id))
             get ("/get-integer" :: Text)
             bodyContains "1"
 
diff --git a/yesod-test/yesod-test.cabal b/yesod-test/yesod-test.cabal
index 24ac3208..ac770758 100644
--- a/yesod-test/yesod-test.cabal
+++ b/yesod-test/yesod-test.cabal
@@ -1,5 +1,5 @@
 name:               yesod-test
-version:            1.6.7
+version:            1.6.8
 license:            MIT
 license-file:       LICENSE
 author:             Nubis <nubis@woobiz.com.ar>