Test the solver's use of the Buildable field.

Author: grayjay

cabal-install/tests/UnitTests/Distribution/Client/Dependency/Modular/Solver.hs

@@ -101,6 +101,13 @@ tests = [
         , runTest $ soft [ ExPref "A" $ mkvrThis 1
                          , ExPref "A" $ mkvrOrEarlier 2] $ mkTest db13 "selectPreferredVersionMultiple4" ["A"] (Just [("A", 1)])
         ]
+     , testGroup "Buildable Field" [
+          testBuildable "avoid building component with unknown dependency" (ExAny "unknown")
+        , testBuildable "avoid building component with unknown extension" (ExExt (UnknownExtension "unknown"))
+        , testBuildable "avoid building component with unknown language" (ExLang (UnknownLanguage "unknown"))
+        , runTest $ mkTest dbBuildable1 "choose flags that set buildable to false" ["pkg"] (Just [("flag1-true", 1), ("flag2-false", 1), ("pkg", 1)])
+        , runTest $ mkTest dbBuildable2 "choose version that sets buildable to false" ["A"] (Just [("A", 1), ("B", 2)])
+        ]
     ]
   where
     indep test      = test { testIndepGoals = True }
@@ -433,6 +440,60 @@ dbLangs1 = [
   , Right $ exAv "C" 1 [ExLang (UnknownLanguage "Haskell3000"), ExAny "B"]
   ]
 
+-- | cabal must choose +disable-lib for "pkg" in order to avoid the unavailable
+-- dependency. False is the default. The flag choice causes "pkg" to depend on
+-- "true-dep".
+testBuildable :: String -> ExampleDependency -> TestTree
+testBuildable testName unavailableDep =
+    runTest $ mkTestExtLang (Just []) (Just []) db testName ["pkg"] expected
+  where
+    expected = (Just [("pkg", 1), ("true-dep", 1)])
+    db = [
+        Right $ exAv "pkg" 1 [
+                   unavailableDep
+                 , ExFlag "disable-lib" NotBuildable (Buildable [])
+                 , ExTest "test" [exFlag "disable-lib"
+                                      [ExAny "true-dep"]
+                                      [ExAny "false-dep"]]
+                 ]
+      , Right $ exAv "true-dep" 1 []
+      , Right $ exAv "false-dep" 1 []
+      ]
+
+-- | cabal must choose +flag1 -flag2 for "pkg", which requires packages
+-- "flag1-true" and "flag2-false".
+dbBuildable1 :: ExampleDb
+dbBuildable1 = [
+    Right $ exAv "pkg" 1
+        [ ExAny "unknown"
+        , ExFlag "flag1" NotBuildable (Buildable [])
+        , ExFlag "flag2" NotBuildable (Buildable [])
+        , ExTest "optional-test"
+              [ ExAny "unknown"
+              , ExFlag "flag1"
+                    (Buildable [ExFlag "flag2" (Buildable []) NotBuildable])
+                    (Buildable [])]
+        , ExTest "test" [ exFlag "flag1" [ExAny "flag1-true"] [ExAny "flag1-false"]
+                        , exFlag "flag2" [ExAny "flag2-true"] [ExAny "flag2-false"]]
+        ]
+  , Right $ exAv "flag1-true" 1 []
+  , Right $ exAv "flag1-false" 1 []
+  , Right $ exAv "flag2-true" 1 []
+  , Right $ exAv "flag2-false" 1 []
+  ]
+
+-- | cabal must pick B-2 to avoid the unknown dependency.
+dbBuildable2 :: ExampleDb
+dbBuildable2 = [
+    Right $ exAv "A" 1 [ExAny "B"]
+  , Right $ exAv "B" 1 [ExAny "unknown"]
+  , Right $ exAv "B" 2
+        [ ExAny "unknown"
+        , ExFlag "disable-lib" NotBuildable (Buildable [])
+        ]
+  , Right $ exAv "B" 3 [ExAny "unknown"]
+  ]
+
 {-------------------------------------------------------------------------------
   Test options
 -------------------------------------------------------------------------------}