Merge pull request #25831 from Luap99/test-doc

update hack/bats to not PASS NOP env and update test README with more system test info

hack/bats

@@ -44,8 +44,6 @@ servers, because we can sudo *starting* the service but can't sudo
 stopping it: by the time the bats tests finish, the sudo timeout will
 have expired. We apologize for the inconvenience.)
 
-$0 also passes through \$OCI_RUNTIME, should you need to test that.
-
 Examples:
 
     \$ $0 220:\"restart cleans up\"
@@ -137,7 +135,6 @@ if [[ "$TEST_ROOT" ]]; then
     sudo    --preserve-env=PODMAN \
             --preserve-env=QUADLET \
             --preserve-env=PODMAN_TEST_DEBUG \
-            --preserve-env=OCI_RUNTIME \
             --preserve-env=CONTAINERS_HELPER_BINARY_DIR \
             --preserve-env=PODMAN_ROOTLESS_USER \
             bats "${bats_opts[@]}" "${bats_filter[@]}" $TESTS

test/README.md

@@ -91,6 +91,8 @@ The following environment variables are supported by the test setup:
  - `PODMAN_DB`: the database backend `sqlite` (default) or `boltdb`.
  - `PODMAN_TEST_IMAGE_CACHE_DIR`: path were the container images should be cached, defaults to `/tmp`.
 
+Note: These variables are used by the integration tests (test/e2e) only not the system tests (test/system).
+
 ### Running a single file of integration tests
 You can run a single file of integration tests using the go test command:
 
@@ -143,7 +145,16 @@ System tests are used for testing the *podman* CLI in the context of a complete
 requires that *podman*, all dependencies, and configurations are in place.  The intention of
 system testing is to match as closely as possible with real-world user/developer use-cases
 and environments. The orchestration of the environments and tests is left to external
-tooling.
+tooling. To test a specific oci runtime it should be set in containers.conf.
+(Note, upstream only tests with crun, there is no guarantee that tests will pass with another
+runtime. We will accept patches to make the tests work with runc, e.g. mostly error message
+checks, but not other runtimes due to the high maintenance overhead.)
+
+Only the following env vars are supported:
+ - `PODMAN`: path to the podman binary, defaults to `podman` in $PATH.
+ - `QUADLET`: path to the quadlet binary, defaults to `/usr/libexec/podman/quadlet`.
+ - `PODMAN_TESTING`: path to the podman-testing binary, defaults to `../../bin/podman-testing` from the system test directory.
+   Note, the binary is used for testing purposes only and is not expected to be shipped to end users.
 
 System tests use Bash Automated Testing System (`bats`) as a testing framework.
 Install it via your package manager or get latest stable version