Ensure results work when no config can be loaded

Why?
====

If no config can be loaded correctly, unused should still function
correctly, albeit with likely more false positives.

src/Unused/Aliases.hs

@@ -24,6 +24,7 @@ groupedTermsAndAliases as ms =
     aliases = map toAlias as
 
 termsAndAliases :: [TermAlias] -> [String] -> [String]
+termsAndAliases [] = id
 termsAndAliases as =
     nub . map T.unpack . concatMap (allAliases aliases . T.pack)
   where

test/Unused/AliasesSpec.hs

@@ -0,0 +1,21 @@
+module Unused.AliasesSpec where
+
+import Test.Hspec
+import Unused.Aliases
+import Unused.ResultsClassifier.Types (TermAlias(..))
+
+main :: IO ()
+main = hspec spec
+
+spec :: Spec
+spec = parallel $
+    describe "termsAndAliases" $ do
+        it "returns the terms if no aliases are provided" $
+            termsAndAliases [] ["method_1", "method_2"] `shouldBe` ["method_1", "method_2"]
+
+        it "adds aliases to the list of terms" $ do
+            let predicateAlias = TermAlias "%s?" "be_%s"
+            let pluralizeAlias = TermAlias "really_%s" "very_%s"
+
+            termsAndAliases [predicateAlias, pluralizeAlias] ["awesome?", "really_cool"]
+                `shouldBe` ["awesome?", "be_awesome", "really_cool", "very_cool"]

test/Unused/ParserSpec.hs

@@ -30,6 +30,18 @@ spec = parallel $
             result `shouldBe`
                 Map.fromList [ ("method_name", r1Results), ("other", r2Results) ]
 
+        it "parses when no config is provided" $ do
+            let r1Matches = [ TermMatch "method_name" "app/path/foo.rb" 1
+                            , TermMatch "method_name" "app/path/other.rb" 5
+                            , TermMatch "method_name" "spec/path/foo_spec.rb" 10
+                            ]
+            let r1Results = TermResults "method_name" r1Matches (Occurrences 1 10) (Occurrences 2 6) (Occurrences 3 16) (Removal Low "used frequently")
+
+            let result = parseResults [] $ SearchResults r1Matches
+
+            result `shouldBe`
+                Map.fromList [ ("method_name", r1Results) ]
+
         it "handles aliases correctly" $ do
             let r1Matches = [ TermMatch "admin?" "app/path/user.rb" 3 ]
 

unused.cabal

@@ -95,6 +95,7 @@ test-suite unused-test
                      , Unused.TermSearch.InternalSpec
                      , Unused.UtilSpec
                      , Unused.Cache.FindArgsFromIgnoredPathsSpec
+                     , Unused.AliasesSpec
                      , Paths_unused
   ghc-options:         -threaded -rtsopts -with-rtsopts=-N -Wall -Werror
   default-language:    Haskell2010