test/buildah-bud: fix checkout to also handle go.mod replace

There is a rather surprising bug in the current test checkout logic. The
go.mod version parsing never actually consider a go.mod replace for
buildah and always read the main version.

This meant a buildah replace actually is testing the old version with
the new code and that means the new tests are not run leading people in
false belive when testing a buildah vendor that it worked. But then
later it fails when doing the proper update without replace.

To fix this first use go list to parse go.mod which is more robust. Then
first check if there is a replace and then use that repo/version
instead.

Signed-off-by: Paul Holzinger <[email protected]>

Author: Luap99

test/buildah-bud/run-buildah-bud-tests

@@ -89,8 +89,20 @@ function die() {
 failhint=
 trap 'if [[ $? != 0 ]]; then if [[ -n $failhint ]]; then echo;echo "***************************************";echo "$failhint";echo;echo "Please see $BUD_TEST_DIR_REL/README.md for advice";fi;fi' 0
 
-# Find the version of buildah we've vendored in, so we can run the right tests
-buildah_version=$(awk "\$1 == \"$BUILDAH_REPO\" { print \$2 }" <go.mod)
+# Find the version of buildah we've vendored in, so we can run the right tests.
+# Note first check if buildah is being replaced with a different version in which case we need to use that one.
+buildah_replace=$(go list -m -f '{{if .Replace}}{{.Replace}}{{end}}' $BUILDAH_REPO)
+buildah_checkout_repo="$BUILDAH_REPO"
+
+if [[ -z "$buildah_replace" ]]; then
+    # No replace this is fine, check the main version
+    buildah_version=$(go list -m -f '{{.Version}}' $BUILDAH_REPO)
+else
+    # replace string is "REPO VERSION" so split this into our two vars
+    buildah_checkout_repo="${buildah_replace% *}"
+    buildah_version="${buildah_replace#* }"
+fi
+
 
 if [[ -z "$buildah_version" ]]; then
     # This should not happen
@@ -147,7 +159,7 @@ if [[ -n $do_checkout ]]; then
     fi
 
     failhint="'git clone' failed - this should never happen!"
-    (set -x;git clone -q $shallow_checkout https://$BUILDAH_REPO $buildah_dir)
+    (set -x;git clone -q $shallow_checkout https://$buildah_checkout_repo $buildah_dir)
 
     # Recent versions of git (like `2.39`) disallow some operations (like `am`)
     # without an identity being set.  In this case, git will throw an error
@@ -193,7 +205,7 @@ if [[ -n $do_checkout ]]; then
     # for a developer to push a new set of diffs to podman-land.
     failhint=
     sed -e "s,\[BASETAG\],${BASE_TAG},g" \
-        -e "s,\[BUILDAHREPO\],${BUILDAH_REPO},g" \
+        -e "s,\[BUILDAHREPO\],${buildah_checkout_repo},g" \
         < ${BUD_TEST_DIR}/make-new-buildah-diffs \
         > make-new-buildah-diffs
     chmod 755 make-new-buildah-diffs