Filter out components that don't match the package, which is still no…

…t quite good.

It really feels like the best thing to do is figure out a way to fix
hpc relative mix paths, instead of not allowing multiple packages and
filtering libraries out..

Cabal/src/Distribution/Simple/Errors.hs

@@ -715,12 +715,12 @@ exceptionMessage e = case e of
     "Could not find test program \""
       ++ cmd
       ++ "\". Did you build the package first?"
-  TestCoverageSupport -> "Test coverage is only supported for projects with at least one (non-backpack) library component."
+  TestCoverageSupport -> "Test coverage is only supported for packages with a library component."
   Couldn'tFindTestProgLibV09 cmd ->
     "Could not find test program \""
       ++ cmd
       ++ "\". Did you build the package first?"
-  TestCoverageSupportLibV09 -> "Test coverage is only supported for projects with at least one (non-backpack) library component."
+  TestCoverageSupportLibV09 -> "Test coverage is only supported for packages with a library component."
   RawSystemStdout errors -> errors
   FindFileCwd fileName -> fileName ++ " doesn't exist"
   FindFileEx fileName -> fileName ++ " doesn't exist"

Cabal/src/Distribution/Simple/Test/ExeV10.hs

@@ -84,7 +84,7 @@ runTest pkg_descr lbi clbi flags suite = do
       dataDirPath = pwd </> PD.dataDir pkg_descr
       tixFile = pwd </> tixFilePath distPref way (testName')
       pkgPathEnv =
-        (pkgPathEnvVar pkg_descr "datadir", dataDirPath)
+       (pkgPathEnvVar pkg_descr "datadir", dataDirPath)
           : existingEnv
       shellEnv = [("HPCTIXFILE", tixFile) | isCoverageEnabled] ++ pkgPathEnv
 
@@ -169,10 +169,17 @@ runTest pkg_descr lbi clbi flags suite = do
   -- Write summary notice to terminal indicating end of test suite
   notice verbosity $ summarizeSuiteFinish suiteLog
 
-  when isCoverageEnabled $
-    if null $ testCoverageDistPrefs flags
-      then dieWithException verbosity TestCoverageSupport
-      else markupPackage verbosity flags lbi distPref pkg_descr [suite]
+  when isCoverageEnabled $ do
+
+    -- Until #9493 is fixed, we expect cabal-install to pass one dist dir per
+    -- library and there being at least one library in the package with the
+    -- testsuite.  When it is fixed, we can remove this predicate and allow a
+    -- testsuite without a library to cover libraries in other packages of the
+    -- same project
+    when (null $ PD.allLibraries pkg_descr) $
+      dieWithException verbosity TestCoverageSupport
+
+    markupPackage verbosity flags lbi distPref pkg_descr [suite]
 
   return suiteLog
   where

Cabal/src/Distribution/Simple/Test/LibV09.hs

@@ -185,10 +185,17 @@ runTest pkg_descr lbi clbi flags suite = do
   -- Write summary notice to terminal indicating end of test suite
   notice verbosity $ summarizeSuiteFinish suiteLog
 
-  when isCoverageEnabled $
-    if null $ testCoverageDistPrefs flags
-      then dieWithException verbosity TestCoverageSupportLibV09
-      else markupPackage verbosity flags lbi distPref pkg_descr [suite]
+  when isCoverageEnabled $ do
+
+    -- Until #9493 is fixed, we expect cabal-install to pass one dist dir per
+    -- library and there being at least one library in the package with the
+    -- testsuite.  When it is fixed, we can remove this predicate and allow a
+    -- testsuite without a library to cover libraries in other packages of the
+    -- same project
+    when (null $ PD.allLibraries pkg_descr) $
+      dieWithException verbosity TestCoverageSupport
+
+    markupPackage verbosity flags lbi distPref pkg_descr [suite]
 
   return suiteLog
   where

cabal-install/src/Distribution/Client/ProjectPlanning.hs

@@ -4312,28 +4312,32 @@ setupHsTestFlags plan (ElaboratedConfiguredPackage{..}) sharedConfig verbosity d
 
     -- The list of non-pre-existing libraries without module holes, i.e. the
     -- main library and sub-libraries components of all the local packages in
-    -- the project that do not require instantiations or are instantiations
-    -- TODO: This currently also includes the testsuite's prefix
+    -- the project that do not require instantiations or are instantiations,
+    -- and the testsuite component.
+    --
     -- TODO: I think that if the packages it depends on are still uninstalled,
     -- this seemingly includes the packages that are not local to the project?!
     -- Weird, because we filter on localToProject!
     -- Try it on cabal-install: cabal test --enable-coverage cabal-install
     librariesToCover =
       mapMaybe
         ( \case
-            InstallPlan.Installed elab@ElaboratedConfiguredPackage{elabModuleShape = modShape}
-              | elabLocalToProject
-              , not (isIndefiniteOrInstantiation modShape) ->
-                  Just elab
-            InstallPlan.Configured elab@ElaboratedConfiguredPackage{elabModuleShape = modShape}
-              | elabLocalToProject
-              , not (isIndefiniteOrInstantiation modShape) ->
-                  Just elab
+            InstallPlan.Installed elab
+              | shouldCoverPkg elab -> Just elab
+            InstallPlan.Configured elab
+              | shouldCoverPkg elab -> Just elab
             _ -> Nothing
         )
         $ Graph.toList
         $ InstallPlan.toGraph plan
 
+    shouldCoverPkg ElaboratedConfiguredPackage{elabModuleShape = modShape, elabPkgSourceId = pkgId}
+      = elabLocalToProject
+      && not (isIndefiniteOrInstantiation modShape)
+      -- TODO(#9493): We can only cover libraries in the same package
+      -- as the testsuite
+      && pkgId == elabPkgSourceId
+
     isIndefiniteOrInstantiation :: ModuleShape -> Bool
     isIndefiniteOrInstantiation = not . Set.null . modShapeRequires
 

cabal-testsuite/PackageTests/MultipleLibraries/Successful/cabal.test.hs

@@ -2,7 +2,8 @@ import Test.Cabal.Prelude
 main = cabalTest $ do
     cabal' "v2-run" ["pkg-abc:program"] >>= assertOutputContains "pkg-def:publib"
 
-    -- # #8609
-    cabal' "v2-test" ["--enable-coverage", "all"]
+    -- #8609
+    expectBroken 8609 $
+      cabal' "v2-test" ["--enable-coverage", "all"]
 
     return ()

cabal-testsuite/PackageTests/TestSuiteTests/ExeV10/cabal.test.hs

@@ -2,3 +2,4 @@ import Test.Cabal.Prelude
 
 main = cabalTest $ do
     cabal "v2-test" []
+    cabal "v2-test" ["--enable-coverage"]