use depset for transitive reexports in HaskellLibraryInfo

Author: prednaz

haskell/cabal.bzl

@@ -611,7 +611,7 @@ def _haskell_cabal_library_impl(ctx):
         user_compile_flags = [],
         user_repl_flags = [],
     )
-    lib_info = HaskellLibraryInfo(package_id = package_id, version = None, exports = [])
+    lib_info = HaskellLibraryInfo(package_id = package_id, version = None, exports = depset([package_id]))
     if with_haddock:
         doc_info = generate_unified_haddock_info(
             this_package_id = package_id,

haskell/private/haskell_impl.bzl

@@ -652,14 +652,16 @@ def haskell_library_impl(ctx):
     )
 
     exports = [
-        reexp[HaskellLibraryInfo]
+        reexp[HaskellLibraryInfo].exports
         for reexp in ctx.attr.exports
-        if HaskellCoverageInfo in reexp
     ]
     lib_info = HaskellLibraryInfo(
         package_id = pkg_id.to_string(my_pkg_id),
         version = version,
-        exports = exports,
+        exports = depset(
+            [pkg_id.to_string(my_pkg_id)],
+            transitive = exports,
+        ),
     )
 
     dep_coverage_data = []
@@ -888,7 +890,7 @@ def haskell_import_impl(ctx):
     lib_info = HaskellLibraryInfo(
         package_id = id,
         version = ctx.attr.version,
-        exports = [],
+        exports = depset([id]),
     )
     default_info = DefaultInfo(
         files = depset(target_files),

haskell/providers.bzl

@@ -31,12 +31,12 @@ HaskellLibraryInfo = provider(
     fields = {
         "package_id": "Workspace unique package identifier.",
         "version": "Package version.",
-        "exports": "List of other `HaskellLibraryInfo` that this package reexports",
+        "exports": "List of `package_id`s that this package exports, that is to say, reexports and this package's own `package_id`",
     },
 )
 
 def all_package_ids(lib_info):
-    return [lib_info.package_id] + [sublib_info.package_id for sublib_info in lib_info.exports]
+    return lib_info.exports.to_list()
 
 # XXX: Does this belong here?
 def all_dependencies_package_ids(deps):

rules_haskell_tests/tests/RunTests.hs

@@ -117,6 +117,14 @@ main = hspec $  around_ printStatsHook $ do
       it "loads module with module dependency" $
         assertSuccess (Process.proc "./.ghcide" ["tests/binary-with-lib/Main.hs"])
 
+    describe "transitive re-exports" $ do
+      it "work" $
+        assertSuccess (bazel ["build", "//tests/package-reexport-transitive"])
+      it "work for long chains" $
+        assertSuccess (bazel ["build", "//tests/package-reexport-transitive:long"])
+      it "do not work for interrupted chains" $
+        assertFailure (bazel ["build", "//tests/package-reexport-transitive:interrupted"])
+
     describe "failures" $ do
       -- Make sure not to include haskell_repl (@repl) or alias (-repl) targets
       -- in the query. Those would not fail under bazel test.
@@ -130,9 +138,6 @@ main = hspec $  around_ printStatsHook $ do
         it "haskell_doc fails with plugins #1549" $
           -- https://github.com/tweag/rules_haskell/issues/1549
           assertFailure (bazel ["build", "//tests/haddock-with-plugin"])
-        it "transitive re-exports do not work #1145" $
-          -- https://github.com/tweag/rules_haskell/issues/1145
-          assertFailure (bazel ["build", "//tests/package-reexport-transitive"])
         it "doctest failure with foreign import #1559" $
           -- https://github.com/tweag/rules_haskell/issues/1559
           assertFailure (bazel ["build", "//tests/haskell_doctest_ffi_1559:doctest-a"])

rules_haskell_tests/tests/package-reexport-transitive/BUILD.bazel

@@ -14,12 +14,38 @@ haskell_library(
 
 haskell_library(
     name = "intermediate",
-    exports = [
-        ":root",
-    ],
-    deps = [
-        ":root",
-    ],
+    exports = [":root"],
+    deps = [":root"],
+)
+
+haskell_library(
+    name = "intermediate1",
+    exports = [":intermediate"],
+    deps = [":intermediate"],
+)
+
+haskell_library(
+    name = "intermediate2",
+    exports = [":intermediate1"],
+    deps = [":intermediate1"],
+)
+
+haskell_library(
+    name = "intermediate3",
+    exports = [":intermediate2"],
+    deps = [":intermediate2"],
+)
+
+haskell_library(
+    name = "intermediate4",
+    exports = [],
+    deps = [":intermediate2"],
+)
+
+haskell_library(
+    name = "intermediate5",
+    exports = [":intermediate4"],
+    deps = [":intermediate4"],
 )
 
 haskell_library(
@@ -30,8 +56,6 @@ haskell_library(
     ],
 )
 
-# Failure test for https://github.com/tweag/rules_haskell/issues/1145
-# TODO Turn into regression test once that issue is resolved.
 haskell_test(
     name = "final",
     srcs = ["Main.hs"],
@@ -47,3 +71,36 @@ test_suite(
     tags = ["manual"],
     tests = [":final"],
 )
+
+haskell_test(
+    name = "final-long",
+    srcs = ["Main.hs"],
+    tags = ["manual"],
+    deps = [
+        ":intermediate3",
+        "//tests/hackage:base",
+    ],
+)
+
+test_suite(
+    name = "long",
+    tags = ["manual"],
+    tests = [":final-long"],
+)
+
+haskell_test(
+    name = "final-interrupted",
+    srcs = ["Main.hs"],
+    tags = ["manual"],
+    deps = [
+        ":intermediate5",
+        "//tests/hackage:base",
+    ],
+)
+
+test_suite(
+    name = "interrupted",
+    tags = ["manual"],
+    tests = [":final-interrupted"],
+)
+