Split some unit tests from UnitTests-megamodule

This helps with recompilation speed while developing

Author: phadej

aeson.cabal

@@ -163,12 +163,18 @@ test-suite aeson-tests
     PropertyRTFunctors
     PropertyTH
     PropUtils
+    Regression.Issue351
     Regression.Issue571
     Regression.Issue967
     SerializationFormatSpec
     Types
     UnitTests
+    UnitTests.FromJSONKey
+    UnitTests.Hashable
+    UnitTests.KeyMapInsertWith
+    UnitTests.MonadFix
     UnitTests.NullaryConstructors
+    UnitTests.UTCTime
 
   build-depends:
       aeson

tests/Regression/Issue351.hs

@@ -0,0 +1,21 @@
+{-# LANGUAGE OverloadedStrings #-}
+module Regression.Issue351 (issue351) where
+
+import Test.Tasty (TestTree, testGroup)
+import Test.Tasty.HUnit (testCase, assertEqual)
+import Data.Maybe (fromMaybe)
+
+import qualified Data.ByteString.Lazy as L
+
+import Data.Aeson
+
+-- A regression test for: https://github.com/bos/aeson/issues/351
+overlappingRegression :: FromJSON a => L.ByteString -> [a]
+overlappingRegression bs = fromMaybe [] $ decode bs
+
+issue351 :: TestTree
+issue351 = testGroup "Issue #351" $ map (testCase "-")
+  [ assertEqual "Int"  ([1, 2, 3] :: [Int])  $ overlappingRegression "[1, 2, 3]"
+  , assertEqual "Char" ("abc"     :: String) $ overlappingRegression "\"abc\""
+  , assertEqual "Char" (""        :: String) $ overlappingRegression "[\"a\", \"b\", \"c\"]"
+  ]