diff --git a/cabal-install-solver/src/Distribution/Solver/Types/PkgConfigDb.hs b/cabal-install-solver/src/Distribution/Solver/Types/PkgConfigDb.hs
index 725fb124bf56bcf7f756af42a6b4f7ee286b9926..14140104ffd8e192858920bb45cc27bd90bb07a3 100644
--- a/cabal-install-solver/src/Distribution/Solver/Types/PkgConfigDb.hs
+++ b/cabal-install-solver/src/Distribution/Solver/Types/PkgConfigDb.hs
@@ -12,7 +12,7 @@
-- Read the list of packages available to pkg-config.
-----------------------------------------------------------------------------
module Distribution.Solver.Types.PkgConfigDb
- ( PkgConfigDb
+ ( PkgConfigDb (..)
, readPkgConfigDb
, pkgConfigDbFromList
, pkgConfigPkgIsPresent
@@ -95,11 +95,12 @@ pkgConfigPkgIsPresent (PkgConfigDb db) pn vr =
Nothing -> False -- Package not present in the DB.
Just Nothing -> True -- Package present, but version unknown.
Just (Just v) -> withinPkgconfigVersionRange v vr
--- If we could not read the pkg-config database successfully we allow
--- the check to succeed. The plan found by the solver may fail to be
--- executed later on, but we have no grounds for rejecting the plan at
--- this stage.
-pkgConfigPkgIsPresent NoPkgConfigDb _ _ = True
+-- If we could not read the pkg-config database successfully we fail.
+-- The plan found by the solver can't be executed later, because pkg-config itself
+-- is going to be called in the build phase to get the library location for linking
+-- so even if there is a library, it would need to be passed manual flags anyway.
+pkgConfigPkgIsPresent NoPkgConfigDb _ _ = False
+
-- | Query the version of a package in the @pkg-config@ database.
diff --git a/cabal-install/tests/UnitTests/Distribution/Solver/Modular/DSL/TestCaseUtils.hs b/cabal-install/tests/UnitTests/Distribution/Solver/Modular/DSL/TestCaseUtils.hs
index 08b52121b7f6c5ab228e56364e6b5c8d772b62b4..93af7178941f9588776a43d2f258925799830db8 100644
--- a/cabal-install/tests/UnitTests/Distribution/Solver/Modular/DSL/TestCaseUtils.hs
+++ b/cabal-install/tests/UnitTests/Distribution/Solver/Modular/DSL/TestCaseUtils.hs
@@ -43,7 +43,7 @@ import Distribution.Verbosity
-- cabal-install
import qualified Distribution.Solver.Types.PackagePath as P
-import Distribution.Solver.Types.PkgConfigDb (PkgConfigDb, pkgConfigDbFromList)
+import Distribution.Solver.Types.PkgConfigDb (PkgConfigDb (..), pkgConfigDbFromList)
import Distribution.Solver.Types.Settings
import Distribution.Solver.Types.Variable
import Distribution.Client.Dependency (foldProgress)
@@ -166,7 +166,7 @@ mkTest :: ExampleDb
-> [String]
-> SolverResult
-> SolverTest
-mkTest = mkTestExtLangPC Nothing Nothing []
+mkTest = mkTestExtLangPC Nothing Nothing (Just [])
mkTestExts :: [Extension]
-> ExampleDb
@@ -174,7 +174,7 @@ mkTestExts :: [Extension]
-> [String]
-> SolverResult
-> SolverTest
-mkTestExts exts = mkTestExtLangPC (Just exts) Nothing []
+mkTestExts exts = mkTestExtLangPC (Just exts) Nothing (Just [])
mkTestLangs :: [Language]
-> ExampleDb
@@ -182,25 +182,25 @@ mkTestLangs :: [Language]
-> [String]
-> SolverResult
-> SolverTest
-mkTestLangs langs = mkTestExtLangPC Nothing (Just langs) []
+mkTestLangs langs = mkTestExtLangPC Nothing (Just langs) (Just [])
-mkTestPCDepends :: [(String, String)]
+mkTestPCDepends :: Maybe [(String, String)]
-> ExampleDb
-> String
-> [String]
-> SolverResult
-> SolverTest
-mkTestPCDepends pkgConfigDb = mkTestExtLangPC Nothing Nothing pkgConfigDb
+mkTestPCDepends mPkgConfigDb = mkTestExtLangPC Nothing Nothing mPkgConfigDb
mkTestExtLangPC :: Maybe [Extension]
-> Maybe [Language]
- -> [(String, String)]
+ -> Maybe [(String, String)]
-> ExampleDb
-> String
-> [String]
-> SolverResult
-> SolverTest
-mkTestExtLangPC exts langs pkgConfigDb db label targets result = SolverTest {
+mkTestExtLangPC exts langs mPkgConfigDb db label targets result = SolverTest {
testLabel = label
, testTargets = targets
, testResult = result
@@ -219,7 +219,7 @@ mkTestExtLangPC exts langs pkgConfigDb db label targets result = SolverTest {
, testDb = db
, testSupportedExts = exts
, testSupportedLangs = langs
- , testPkgConfigDb = pkgConfigDbFromList pkgConfigDb
+ , testPkgConfigDb = maybe NoPkgConfigDb pkgConfigDbFromList mPkgConfigDb
, testEnableAllTests = EnableAllTests False
}
diff --git a/cabal-install/tests/UnitTests/Distribution/Solver/Modular/Solver.hs b/cabal-install/tests/UnitTests/Distribution/Solver/Modular/Solver.hs
index 3abd45f5047ed3df0caec99a06caecf242421484..33e8b41a7d35c5d968291b17efbeb9dbb5feddc2 100644
--- a/cabal-install/tests/UnitTests/Distribution/Solver/Modular/Solver.hs
+++ b/cabal-install/tests/UnitTests/Distribution/Solver/Modular/Solver.hs
@@ -253,10 +253,12 @@ tests = [
, runTest $ mkTest dbBuildable2 "choose version that sets buildable to false" ["A"] (solverSuccess [("A", 1), ("B", 2)])
]
, testGroup "Pkg-config dependencies" [
- runTest $ mkTestPCDepends [] dbPC1 "noPkgs" ["A"] anySolverFailure
- , runTest $ mkTestPCDepends [("pkgA", "0")] dbPC1 "tooOld" ["A"] anySolverFailure
- , runTest $ mkTestPCDepends [("pkgA", "1.0.0"), ("pkgB", "1.0.0")] dbPC1 "pruneNotFound" ["C"] (solverSuccess [("A", 1), ("B", 1), ("C", 1)])
- , runTest $ mkTestPCDepends [("pkgA", "1.0.0"), ("pkgB", "2.0.0")] dbPC1 "chooseNewest" ["C"] (solverSuccess [("A", 1), ("B", 2), ("C", 1)])
+ runTest $ mkTestPCDepends (Just []) dbPC1 "noPkgs" ["A"] anySolverFailure
+ , runTest $ mkTestPCDepends (Just [("pkgA", "0")]) dbPC1 "tooOld" ["A"] anySolverFailure
+ , runTest $ mkTestPCDepends (Just [("pkgA", "1.0.0"), ("pkgB", "1.0.0")]) dbPC1 "pruneNotFound" ["C"] (solverSuccess [("A", 1), ("B", 1), ("C", 1)])
+ , runTest $ mkTestPCDepends (Just [("pkgA", "1.0.0"), ("pkgB", "2.0.0")]) dbPC1 "chooseNewest" ["C"] (solverSuccess [("A", 1), ("B", 2), ("C", 1)])
+ , runTest $ mkTestPCDepends Nothing dbPC1 "noPkgConfigFailure" ["A"] anySolverFailure
+ , runTest $ mkTestPCDepends Nothing dbPC1 "noPkgConfigSuccess" ["D"] (solverSuccess [("D",1)])
]
, testGroup "Independent goals" [
runTest $ indep $ mkTest db16 "indepGoals1" ["A", "B"] (solverSuccess [("A", 1), ("B", 1), ("C", 1), ("D", 1), ("D", 2), ("E", 1)])
@@ -1665,7 +1667,7 @@ dbLangs1 = [
testBuildable :: String -> ExampleDependency -> TestTree
testBuildable testName unavailableDep =
runTest $
- mkTestExtLangPC (Just []) (Just [Haskell98]) [] db testName ["pkg"] expected
+ mkTestExtLangPC (Just []) (Just [Haskell98]) (Just []) db testName ["pkg"] expected
where
expected = solverSuccess [("false-dep", 1), ("pkg", 1)]
db = [
@@ -1718,12 +1720,14 @@ dbBuildable2 = [
]
-- | Package databases for testing @pkg-config@ dependencies.
+-- when no pkgconfig db is present, cabal must pick flag1 false and flag2 true to avoid the pkg dependency.
dbPC1 :: ExampleDb
dbPC1 = [
Right $ exAv "A" 1 [ExPkg ("pkgA", 1)]
, Right $ exAv "B" 1 [ExPkg ("pkgB", 1), ExAny "A"]
, Right $ exAv "B" 2 [ExPkg ("pkgB", 2), ExAny "A"]
, Right $ exAv "C" 1 [ExAny "B"]
+ , Right $ exAv "D" 1 [exFlagged "flag1" [ExAny "A"] [], exFlagged "flag2" [] [ExAny "A"]]
]
-- | Test for the solver's summarized log. The final conflict set is {A, F},
diff --git a/changelog.d/pr-7621 b/changelog.d/pr-7621
new file mode 100644
index 0000000000000000000000000000000000000000..4980160e3ae7f46a861ac364a6866045add1251f
--- /dev/null
+++ b/changelog.d/pr-7621
@@ -0,0 +1,10 @@
+synopsis: Backtrack when no pkg-config is present
+packages: Cabal
+prs: #7621
+issues: #7448
+
+description: {
+
+When solving for pkgconfig-depends, when pkg-config is not present, the cabal solver will now backtrack and try a different automatic flag and dependency configuration, just as it does if pkg-config is present, but does not contain the specified package.
+
+}