lib: expectEq', expectParseEq: pretty-print compared values (#812)

hledger-lib/Hledger/Utils/Test.hs

@@ -7,6 +7,7 @@ import Control.Exception
 import Control.Monad
 import Control.Monad.State.Strict (StateT)
 --import Control.Monad.State.Strict (evalStateT)
+import Data.CallStack
 import Data.Functor.Identity
 import Data.List
 import qualified Data.Text as T
@@ -102,7 +103,12 @@ runEasyTests args easytests = (do
 expectParseEq :: (Monoid st, Eq a, Show a) => StateT st (ParsecT CustomErr T.Text Identity) a -> T.Text -> a -> EasyTest.Test ()
 expectParseEq parser input expected = do
   let ep = runIdentity $ parseWithState mempty parser input
-  either (fail.("parse error at "++).parseErrorPretty) (flip expectEq expected) ep
+  either (fail.("parse error at "++).parseErrorPretty) (flip expectEq' expected) ep
+
+-- | Like easytest's expectEq, but pretty-prints the values in failure output. 
+expectEq' :: (Eq a, Show a, HasCallStack) => a -> a -> EasyTest.Test ()
+expectEq' x y = if x == y then ok else crash $
+  "expected:\n" <> T.pack (pshow x) <> "\nbut got:\n" <> T.pack (pshow y) <> "\n"
 
 -- | Run some hunit tests, returning True if there was a problem.
 -- With arguments, runs only tests whose names contain the first argument

hledger-lib/hledger-lib.cabal

@@ -2,7 +2,7 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: b52d450888004e007b3689cfe42d916ab8e8af3bc91a6a374ff022a719e86611
+-- hash: 297d8918f59c94ceae6e61bc5df3a67247c22d5cd135ae9f9ffc8fd84cf144d7
 
 name:           hledger-lib
 version:        1.10.99
@@ -111,6 +111,7 @@ library
     , base-compat-batteries >=0.10.1 && <0.11
     , blaze-markup >=0.5.1
     , bytestring
+    , call-stack
     , cmdargs >=0.10
     , containers
     , csv
@@ -209,6 +210,7 @@ test-suite doctests
     , base-compat-batteries >=0.10.1 && <0.11
     , blaze-markup >=0.5.1
     , bytestring
+    , call-stack
     , cmdargs >=0.10
     , containers
     , csv
@@ -308,6 +310,7 @@ test-suite easytests
     , base-compat-batteries >=0.10.1 && <0.11
     , blaze-markup >=0.5.1
     , bytestring
+    , call-stack
     , cmdargs >=0.10
     , containers
     , csv
@@ -407,6 +410,7 @@ test-suite hunittests
     , base-compat-batteries >=0.10.1 && <0.11
     , blaze-markup >=0.5.1
     , bytestring
+    , call-stack
     , cmdargs >=0.10
     , containers
     , csv

hledger-lib/package.yaml

@@ -45,6 +45,7 @@ dependencies:
 - array
 - blaze-markup >=0.5.1
 - bytestring
+- call-stack
 - cmdargs >=0.10
 - containers
 - csv