[PATCH v3 12/12] CI: add a "linux-cmake-test" to run cmake & ctest on linux

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

Since [1] the "cmake" build method should work properly on Linux, but
as seen in preceding commits there were various bugs in it, which are
hopefully now all fixed.

To ensure that it doesn't break again let's add a "linux-cmake-ctest"
target to build and test "cmake" on Linux, in addition to that we'll
also run the tests with "ctest" instead of "make" or "prove", so we
can assert that testing with that method works..

This also stress tests running "cmake" (and "ctest") out of a build
directory that isn't the top-level. The "vs-build" job uses "cmake"
since [2], but clobbers the top-level "Makefile" and builds in the
top-level directory.

That was the reason for why we didn't spot that various tests still
required missing "mergetools/*" etc, which was fixed by using
"$GIT_SOURCE_DIR" in a preceding commit.

Since the "ci/lib.sh" already creates and exports a
GIT_TEST_OPTS="..." we'll pick that up in our CI, see the preceding
commit. Because we pass the "--verbose-log -x
--github-workflow-markup" in the GitHub CI as a result the interaction
with "handle_failed_tests" here works correctly. I.e. on failure we'll
have saved "t/test-results/*.{exit,out,markup}" files relevant to the
failing test(s).

1. f31b6244950 (Merge branch 'yw/cmake-updates', 2022-06-07)
2. 4c2c38e800f (ci: modification of main.yml to use cmake for vs-build
   job, 2020-06-26)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 .github/workflows/main.yml |  3 +++
 ci/run-build-and-tests.sh  | 13 +++++++++++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index bd6f75b8e0f..68c2e134646 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -238,6 +238,9 @@ jobs:
             os: ubuntu
             cc_package: gcc-8
             pool: ubuntu-latest
+          - jobname: linux-cmake-ctest
+            cc: gcc
+            pool: ubuntu-latest
           - jobname: osx-clang
             cc: clang
             pool: macos-latest
diff --git a/ci/run-build-and-tests.sh b/ci/run-build-and-tests.sh
index 8ebff425967..a3ae5ff3972 100755
--- a/ci/run-build-and-tests.sh
+++ b/ci/run-build-and-tests.sh
@@ -45,10 +45,19 @@ pedantic)
 	;;
 esac
 
-group Build make
+mc=
+if test "$jobname" = "linux-cmake-ctest"
+then
+	cb=contrib/buildsystems
+	group CMake cmake -S "$cb" -B "$cb/out"
+	mc="-C $cb/out"
+fi
+
+group Build make $mc
+
 if test -n "$run_tests"
 then
-	group "Run tests" make test ||
+	group "Run tests" make $mc test ||
 	handle_failed_tests
 fi
 check_unignored_build_artifacts
-- 
2.38.0.1280.g8136eb6fab2