Allow --pattern|-p option to repeat

The effect of multiple -p options is the same as &&-ing the expressions
together, but allowing them to be specified in separate options makes
scripting test commands simpler.

core/Test/Tasty/Patterns.hs

@@ -18,6 +18,7 @@ import Test.Tasty.Patterns.Parser
 import Test.Tasty.Patterns.Eval
 
 import Data.Char
+import Data.Foldable (foldl')
 import Data.Typeable
 import Options.Applicative hiding (Success)
 #if !MIN_VERSION_base(4,11,0)
@@ -44,7 +45,11 @@ instance IsOption TestPattern where
   parseValue = parseTestPattern
   optionName = return "pattern"
   optionHelp = return "Select only tests which satisfy a pattern or awk expression"
-  optionCLParser = mkOptionCLParser (short 'p' <> metavar "PATTERN")
+  optionCLParser = fmap (foldl' testPatternAnd noPattern) $ some $ mkOptionCLParser (short 'p' <> metavar "PATTERN")
+    where
+    testPatternAnd (TestPattern Nothing) (TestPattern mbY) = TestPattern mbY
+    testPatternAnd (TestPattern mbX) (TestPattern Nothing) = TestPattern mbX
+    testPatternAnd (TestPattern (Just x)) (TestPattern (Just y)) = TestPattern (Just (And x y))
 
 -- | @since 1.2
 parseExpr :: String -> Maybe Expr