Merge pull request haskell#3432 from dcoutts/issue-3324

Add a regression test for issue haskell#3324

cabal-install/cabal-install.cabal

@@ -119,6 +119,11 @@ Extra-Source-Files:
   tests/IntegrationTests2/exception/configure/a.cabal
   tests/IntegrationTests2/exception/no-pkg/empty.in
   tests/IntegrationTests2/exception/no-pkg2/cabal.project
+  tests/IntegrationTests2/regression/3324/cabal.project
+  tests/IntegrationTests2/regression/3324/p/P.hs
+  tests/IntegrationTests2/regression/3324/p/p.cabal
+  tests/IntegrationTests2/regression/3324/q/Q.hs
+  tests/IntegrationTests2/regression/3324/q/q.cabal
   -- END gen-extra-source-files
 
 source-repository head

cabal-install/tests/IntegrationTests2.hs

@@ -46,6 +46,10 @@ tests =
 --    , testCase "register"   testExceptionInRegisterStep
     ]
     --TODO: need to repeat for packages for the store
+
+  , testGroup "Regression tests" $
+    [ testCase "issue #3324" testRegressionIssue3324
+    ]
   ]
 
 testExceptionInFindingPackage :: Assertion
@@ -94,20 +98,43 @@ testExceptionInBuildStep = do
     plan  <- planProject testdir config
     plan' <- executePlan plan
     (_pkga1, failure) <- expectPackageFailed plan' pkgidA1
-    case failure of
-      BuildFailed _str -> return ()
-      _ -> assertFailure $ "expected BuildFailed, got " ++ show failure 
+    expectBuildFailed failure
   where
     testdir = "exception/build"
     config  = mempty
     pkgidA1 = PackageIdentifier (PackageName "a") (Version [1] [])
 
+-- | See <https://github.com/haskell/cabal/issues/3324>
+--
+testRegressionIssue3324 :: Assertion
+testRegressionIssue3324 = do
+    -- expected failure first time due to missing dep
+    plan1 <- executePlan =<< planProject testdir config
+    (_pkgq, failure) <- expectPackageFailed plan1 pkgidQ
+    expectBuildFailed failure
+
+    -- add the missing dep, now it should work
+    let qcabal  = basedir </> testdir </> "q" </> "q.cabal"
+    withFileFinallyRestore qcabal $ do
+      appendFile qcabal ("  build-depends: p\n")
+      plan2 <- executePlan =<< planProject testdir config
+      _ <- expectPackageInstalled plan2 pkgidP
+      _ <- expectPackageInstalled plan2 pkgidQ
+      return ()
+  where
+    testdir = "regression/3324"
+    config  = mempty
+    pkgidP  = PackageIdentifier (PackageName "p") (Version [0,1] [])
+    pkgidQ  = PackageIdentifier (PackageName "q") (Version [0,1] [])
 
 
 ---------------------------------
 -- Test utils to plan and build
 --
 
+basedir :: FilePath
+basedir = "tests" </> "IntegrationTests2"
+
 planProject :: FilePath -> ProjectConfig -> IO PlanDetails
 planProject testdir cliConfig = do
     cabalDir <- defaultCabalDir
@@ -259,3 +286,20 @@ expectPlanPackage plan pkgid =
                    "expected to find only one instance of " ++ display pkgid
                 ++ " in the install plan but there's several"
 
+expectBuildFailed :: BuildFailure -> IO ()
+expectBuildFailed (BuildFailed _str) = return ()
+expectBuildFailed failure = assertFailure $ "expected BuildFailed, got "
+                                         ++ show failure
+
+---------------------------------------
+-- Other utils
+--
+
+-- | Allow altering a file during a test, but then restore it afterwards
+--
+withFileFinallyRestore :: FilePath -> IO a -> IO a
+withFileFinallyRestore file action = do
+    copyFile file backup
+    action `finally` renameFile backup file
+  where
+    backup = file <.> "backup"

cabal-install/tests/IntegrationTests2/exception/build/a.cabal

@@ -5,4 +5,4 @@ cabal-version: >= 1.2
 
 executable a
   main-is: Main.hs
-  build-depends: haskell2010
+  build-depends: base

cabal-install/tests/IntegrationTests2/regression/3324/cabal.project

@@ -0,0 +1 @@
+packages: p q

cabal-install/tests/IntegrationTests2/regression/3324/p/P.hs

@@ -0,0 +1,4 @@
+module P where
+
+p :: Int
+p = 42

cabal-install/tests/IntegrationTests2/regression/3324/p/p.cabal

@@ -0,0 +1,8 @@
+name: p
+version: 0.1
+build-type: Simple
+cabal-version: >= 1.2
+
+library
+  exposed-modules: P
+  build-depends: base

cabal-install/tests/IntegrationTests2/regression/3324/q/Q.hs

@@ -0,0 +1,6 @@
+module Q where
+
+import P
+
+q :: Int
+q = p

cabal-install/tests/IntegrationTests2/regression/3324/q/q.cabal

@@ -0,0 +1,10 @@
+name: q
+version: 0.1
+build-type: Simple
+cabal-version: >= 1.2
+
+library
+  exposed-modules: Q
+  build-depends: base
+  -- missing a dep on p here, so expect failure initially
+