Add spec for stack dot

src/test/Stack/DotSpec.hs

@@ -0,0 +1,92 @@
+{-# LANGUAGE OverloadedStrings #-}
+-- | Test suite for Stack.Dot
+module Stack.DotSpec where
+
+import           Data.ByteString.Char8 (ByteString)
+import           Data.Functor.Identity
+import qualified Data.Map as Map
+import           Data.Maybe (fromMaybe)
+import           Data.Set (Set)
+import qualified Data.Set as Set
+import           Options.Applicative (execParserPure,idm,prefs,info,getParseResult)
+import           Stack.Types
+import           Test.Hspec
+
+import           Stack.Dot
+
+spec :: Spec
+spec = do
+  let graph =
+         Map.mapKeys pkgName
+       . fmap (Set.map pkgName)
+       . Map.fromList $ [("one",Set.fromList ["base","free"])
+                        ,("two",Set.fromList ["base","free","mtl","transformers","one"])
+                        ]
+  describe "Stack.Dot" $ do
+    it "does nothing if depth is 0" $
+      resolveDependencies (Just 0) graph stubLoader `shouldBe` return graph
+
+    it "with depth 1, more dependencies are resolved" $ do
+      let graph' = Map.insert (pkgName "cycle") (Set.singleton (pkgName "cycle")) graph
+          resultGraph = runIdentity (resolveDependencies (Just 0) graph stubLoader)
+          resultGraph' = runIdentity (resolveDependencies (Just 1) graph' stubLoader)
+      Map.size resultGraph < Map.size resultGraph' `shouldBe` True
+
+    it "cycles are ignored" $ do
+       let graph' = Map.insert (pkgName "cycle") (Set.singleton (pkgName "cycle")) graph
+           resultGraph = resolveDependencies Nothing graph stubLoader
+           resultGraph' = resolveDependencies Nothing graph' stubLoader
+       fmap Map.size resultGraph' `shouldBe` fmap ((+1) . Map.size) resultGraph
+
+  where graphElem e graph = Set.member e . Set.unions . Map.elems $ graph
+
+{- Helper functions below -}
+
+-- Unsafe internal helper to create a package name
+pkgName :: ByteString -> PackageName
+pkgName = fromMaybe failure . parsePackageName
+  where
+   failure = (error "Internal error during package name creation in DotSpec.pkgName")
+
+-- Stub, simulates the function to load package dependecies
+stubLoader :: PackageName -> Identity (Set PackageName)
+stubLoader name = return . Set.fromList . map pkgName $ case show name of
+  "StateVar" -> ["stm","transformers"]
+  "array" -> []
+  "bifunctors" -> ["semigroupoids","semigroups","tagged"]
+  "binary" -> ["array","bytestring","containers"]
+  "bytestring" -> ["deepseq","ghc-prim","integer-gmp"]
+  "comonad" -> ["containers","contravariant","distributive"
+               ,"semigroups","tagged","transformers","transformers-compat"
+               ]
+  "cont" -> ["StateVar","semigroups","transformers","transformers-compat","void"]
+  "containers" -> ["array","deepseq","ghc-prim"]
+  "deepseq" -> ["array"]
+  "distributive" -> ["ghc-prim","tagged","transformers","transformers-compat"]
+  "free" -> ["bifunctors","comonad","distributive","mtl"
+            ,"prelude-extras","profunctors","semigroupoids"
+            ,"semigroups","template-haskell","transformers"
+            ]
+  "ghc" -> []
+  "hashable" -> ["bytestring","ghc-prim","integer-gmp","text"]
+  "integer" -> []
+  "mtl" -> ["transformers"]
+  "nats" -> []
+  "one" -> ["free"]
+  "prelude" -> []
+  "profunctors" -> ["comonad","distributive","semigroupoids","tagged","transformers"]
+  "semigroupoids" -> ["comonad","containers","contravariant","distributive"
+                     ,"semigroups","transformers","transformers-compat"
+                     ]
+  "semigroups" -> ["bytestring","containers","deepseq","hashable"
+                  ,"nats","text","unordered-containers"
+                  ]
+  "stm" -> ["array"]
+  "tagged" -> ["template-haskell"]
+  "template" -> []
+  "text" -> ["array","binary","bytestring","deepseq","ghc-prim","integer-gmp"]
+  "transformers" -> []
+  "two" -> ["free","mtl","one","transformers"]
+  "unordered" -> ["deepseq","hashable"]
+  "void" -> ["ghc-prim","hashable","semigroups"]
+  _ -> []

stack.cabal

@@ -226,6 +226,8 @@ test-suite stack-test
                 , resourcet
                 , Cabal
                 , text
+                , optparse-applicative
+                , bytestring
   default-language:    Haskell2010
 
 test-suite stack-integration-test