Compatibility with envparse-0.5.0

Immediately after implementing kept, envparse-0.5 was released and
Stackage nightly picked it up. In order to stay, we need to be
compatible.

library/Freckle/App/Env.hs

@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 -- | Parse the shell environment for configuration
 --
 -- A minor extension of [envparse](https://hackage.haskell.org/package/envparse).
@@ -76,14 +78,26 @@ newtype On a = On a
 flag :: Off a -> On a -> String -> Mod Flag a -> Parser Error a
 flag (Off f) (On t) n m = Env.flag f t n m
 
--- | Modify a 'Parser' so all variables are as if they used 'keep'
+-- | Modify a 'Parser' so variables are never removed after reading
+--
+-- In @envparse-0.4@, read variables are removed from the environment. This is
+-- often problematic (e.g. in tests that repeatedly load an app and re-read the
+-- environment), and the security benefits are minor. This function will make
+-- them all behave as if @keep@ was used.
 --
--- By default, read variables are removed from the environment. This is often
--- problematic (e.g. in tests that repeatedly load an app and re-read the
--- environment), and the security benefits are minor.
+-- In @envparse-0.5@, the default is reversed and @sensitive@ can be used to
+-- explicitly unset read variables. This function will make them all behave as
+-- if @sensitive@ was /not/ used.
 --
 kept :: Parser e a -> Parser e a
-kept = Parser . hoistAlt (\v -> v { varfKeep = True }) . unParser
+kept = Parser . hoistAlt go . unParser
+ where
+  go v =
+#if MIN_VERSION_envparse(0,5,0)
+    v { varfSensitive = False }
+#else
+    v { varfKeep = True }
+#endif
 
 -- | Create a 'Reader' from a simple parser function
 --

stack-nightly.yaml

@@ -1,4 +1,4 @@
-resolver: nightly-2022-06-06
+resolver: nightly-2022-06-14
 extra-deps:
   - Blammo-1.0.0.1
   - context-0.2.0.0

stack-nightly.yaml.lock

@@ -55,7 +55,7 @@ packages:
     hackage: scientist-0.0.0.0
 snapshots:
 - completed:
-    size: 605110
-    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/nightly/2022/6/6.yaml
-    sha256: 26ea900ee8601fee24ff84981e92f304d384c73ee32d5504299133b5eb177e87
-  original: nightly-2022-06-06
+    size: 611629
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/nightly/2022/6/14.yaml
+    sha256: 0053bc98eb1eae51d523de1ea060941285b4692e93d539b49e64429d50071fe4
+  original: nightly-2022-06-14