support Kubernetes 1.25 + Ginkgo v2

Kubernetes 1.25 is switching to Ginkgo v2 for the e2e.test suite.
This has two implications:
- we must built a matching ginkgo binary because communication
  between the ginkgo binary and library changed, affecting for
  example running of parallel tests: this is done by using the
  Kubernetes make rules to build the binary when using the Kubernetes
  e2e.test suite
- the ginkgo v2 JUnit file is slightly different: filter-junit.go
  now first tries the old format, then the new one

filter-junit.go

@@ -35,10 +35,18 @@ var (
 )
 
 /*
- * TestSuite represents a JUnit file. Due to how encoding/xml works, we have
+ * TestResults represents a JUnit file. Due to how encoding/xml works, we have
  * represent all fields that we want to be passed through. It's therefore
  * not a complete solution, but good enough for Ginkgo + Spyglass.
+ *
+ * Before Kubernetes 1.25 and ginkgo v2, we directly had <testsuite> in the
+ * JUnit file. Now we get <testsuites> and inside it the <testsuite>.
  */
+type TestResults struct {
+	XMLName   string    `xml:"testsuites"`
+	TestSuite TestSuite `xml:"testsuite"`
+}
+
 type TestSuite struct {
 	XMLName   string     `xml:"testsuite"`
 	TestCases []TestCase `xml:"testcase"`
@@ -93,7 +101,15 @@ func main() {
 			}
 		}
 		if err := xml.Unmarshal(data, &junit); err != nil {
-			panic(err)
+			if err.Error() != "expected element type <testsuite> but have <testsuites>" {
+				panic(err)
+			}
+			// Fall back to Ginkgo v2 format.
+			var junitv2 TestResults
+			if err := xml.Unmarshal(data, &junitv2); err != nil {
+				panic(err)
+			}
+			junit = junitv2.TestSuite
 		}
 	}
 

prow.sh

@@ -93,7 +93,10 @@ configvar CSI_PROW_GO_VERSION_KIND "${CSI_PROW_GO_VERSION_BUILD}" "Go version fo
 configvar CSI_PROW_GO_VERSION_GINKGO "${CSI_PROW_GO_VERSION_BUILD}" "Go version for building ginkgo" # depends on CSI_PROW_GINKGO_VERSION below
 
 # ginkgo test runner version to use. If the pre-installed version is
-# different, the desired version is built from source.
+# different, the desired version is built from source. For Kubernetes,
+# the version built via "make WHAT=vendor/github.com/onsi/ginkgo/ginkgo" is
+# used, which is guaranteed to match what the Kubernetes e2e.test binary
+# needs.
 configvar CSI_PROW_GINKGO_VERSION v1.7.0 "Ginkgo"
 
 # Ginkgo runs the E2E test in parallel. The default is based on the number
@@ -440,6 +443,10 @@ install_kind () {
 
 # Ensure that we have the desired version of the ginkgo test runner.
 install_ginkgo () {
+    if [ -e "${CSI_PROW_BIN}/ginkgo" ]; then
+        return
+    fi
+
     # CSI_PROW_GINKGO_VERSION contains the tag with v prefix, the command line output does not.
     if [ "v$(ginkgo version 2>/dev/null | sed -e 's/.* //')" = "${CSI_PROW_GINKGO_VERSION}" ]; then
         return
@@ -943,7 +950,9 @@ install_e2e () {
         patch_kubernetes "${GOPATH}/src/${CSI_PROW_E2E_IMPORT_PATH}" "${CSI_PROW_WORK}" &&
         go_version="${CSI_PROW_GO_VERSION_E2E:-$(go_version_for_kubernetes "${GOPATH}/src/${CSI_PROW_E2E_IMPORT_PATH}" "${CSI_PROW_E2E_VERSION}")}" &&
         run_with_go "$go_version" make WHAT=test/e2e/e2e.test "-C${GOPATH}/src/${CSI_PROW_E2E_IMPORT_PATH}" &&
-        ln -s "${GOPATH}/src/${CSI_PROW_E2E_IMPORT_PATH}/_output/bin/e2e.test" "${CSI_PROW_WORK}"
+        ln -s "${GOPATH}/src/${CSI_PROW_E2E_IMPORT_PATH}/_output/bin/e2e.test" "${CSI_PROW_WORK}" &&
+        run_with_go "$go_version" make WHAT=vendor/github.com/onsi/ginkgo/ginkgo "-C${GOPATH}/src/${CSI_PROW_E2E_IMPORT_PATH}" &&
+        ln -s "${GOPATH}/src/${CSI_PROW_E2E_IMPORT_PATH}/_output/bin/ginkgo" "${CSI_PROW_BIN}"
     else
         run_with_go "${CSI_PROW_GO_VERSION_E2E}" go test -c -o "${CSI_PROW_WORK}/e2e.test" "${CSI_PROW_E2E_IMPORT_PATH}/test/e2e"
     fi