Accept subcomponents as dependencies (close #382)

CHANGELOG.md

@@ -1,3 +1,6 @@
+## next
+  - Accept subcomponents as dependencies (close #382)
+
 ## Changes in 0.34.1
   - Fix a bug in `github: ...` introduced with `0.34.0`
     (f63eb19b956517b4dd8e28dc5785be5889a99298)

hpack.cabal

@@ -27,7 +27,7 @@ library
       src
   ghc-options: -Wall
   build-depends:
-      Cabal >=2.2
+      Cabal >=3.0.0.0
     , Glob >=0.9.0
     , aeson >=1.4.3.0
     , base >=4.9 && <5
@@ -83,7 +83,7 @@ executable hpack
       driver
   ghc-options: -Wall
   build-depends:
-      Cabal >=2.2
+      Cabal >=3.0.0.0
     , Glob >=0.9.0
     , aeson >=1.4.3.0
     , base >=4.9 && <5
@@ -119,7 +119,7 @@ test-suite spec
   ghc-options: -Wall
   cpp-options: -DTEST
   build-depends:
-      Cabal >=2.2
+      Cabal >=3.0.0.0
     , Glob >=0.9.0
     , HUnit >=1.6.0.0
     , QuickCheck

package.yaml

@@ -23,7 +23,7 @@ dependencies:
   - yaml >= 0.10.0
   - aeson >= 1.4.3.0
   - scientific
-  - Cabal >= 2.2
+  - Cabal >= 3.0.0.0
   - pretty
   - bifunctors
   - cryptonite

src/Hpack/Syntax/Dependencies.hs

@@ -9,9 +9,12 @@ module Hpack.Syntax.Dependencies (
 
 import qualified Control.Monad.Fail as Fail
 import           Data.Text (Text)
+import           Data.List
 import qualified Data.Text as T
 import           Data.Semigroup (Semigroup(..))
 import qualified Distribution.Package as D
+import qualified Distribution.Types.LibraryName as D
+import           Distribution.Pretty (prettyShow)
 import           Data.Map.Lazy (Map)
 import qualified Data.Map.Lazy as Map
 import           GHC.Exts
@@ -64,4 +67,10 @@ parseDependency :: Fail.MonadFail m => String -> Text -> m (String, DependencyVe
 parseDependency subject = fmap fromCabal . cabalParse subject . T.unpack
   where
     fromCabal :: D.Dependency -> (String, DependencyVersion)
-    fromCabal d = (D.unPackageName $ D.depPkgName d, DependencyVersion Nothing . versionConstraintFromCabal $ D.depVerRange d)
+    fromCabal d = (toName (D.depPkgName d) (toList $ D.depLibraries d), DependencyVersion Nothing . versionConstraintFromCabal $ D.depVerRange d)
+
+    toName :: D.PackageName -> [D.LibraryName] -> String
+    toName package components = prettyShow package <> case components of
+      [D.LMainLibName] -> ""
+      [D.LSubLibName lib] -> ":" <> prettyShow lib
+      xs -> ":{" <> (intercalate "," $ map prettyShow [name | D.LSubLibName name <- xs]) <> "}"

test/Hpack/Syntax/DependenciesSpec.hs

@@ -1,5 +1,6 @@
 {-# LANGUAGE QuasiQuotes #-}
 {-# LANGUAGE OverloadedLists #-}
+{-# LANGUAGE OverloadedStrings #-}
 module Hpack.Syntax.DependenciesSpec (spec) where
 
 import           Helper
@@ -18,6 +19,16 @@ defaultInfo = DependencyInfo [] anyVersion
 
 spec :: Spec
 spec = do
+  describe "parseDependency" $ do
+    it "accepts dependencies" $ do
+      parseDependency "dependency" "foo" `shouldReturn` ("foo", DependencyVersion Nothing AnyVersion)
+
+    it "accepts dependencies with a subcomponent" $ do
+      parseDependency "dependency" "foo:bar" `shouldReturn` ("foo:bar", DependencyVersion Nothing AnyVersion)
+
+    it "accepts dependencies with multiple subcomponents" $ do
+      parseDependency "dependency" "foo:{bar,baz}" `shouldReturn` ("foo:{bar,baz}", DependencyVersion Nothing AnyVersion)
+
   describe "fromValue" $ do
     context "when parsing Dependencies" $ do
       context "with a scalar" $ do