Run test-go-mod unpinned (#5011)

* Remove go module ci job

* Add script that runs go mod tidy with replace statements

* Invoke one script from the makefile and pass in the command to run in the pinned context

---------

Co-authored-by: Anna Song <annasong@google.com>

Makefile

@@ -152,7 +152,7 @@ functions-examples-all:
 	done
 
 test-go-mod:
-	./hack/for-each-module.sh "go list -m -json all > /dev/null && go mod tidy -v"
+	./hack/for-each-module.sh "\$$KUSTOMIZE_ROOT/hack/with-unpinned-kust-dev.sh 'go mod tidy -v'"
 
 .PHONY:
 verify-kustomize-e2e: $(MYGOBIN)/mdrip $(MYGOBIN)/kind

hack/with-unpinned-kust-dev.sh

@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+# Copyright 2023 The Kubernetes Authors.
+# SPDX-License-Identifier: Apache-2.0
+
+set -x
+set -e
+set -o pipefail
+set -o nounset
+
+# This script uses 'replace' statements to 'unpin' local modules from module versions go.mod normally
+# requires, so that the local version will be used instead. With the advent of Workspace mode, we no longer
+# need to do this in general in between releases. However, some key commands like `go mod tidy` are not
+# Workspace-aware and thus will fail if API changes between modules exist on master. This script allows us to
+# test those commands without requiring unpin operations in our release workflow.
+
+if [[ -z "${1-}" ]] ; then
+  echo "Usage: $0 <cmd>"
+  echo "Example: $0 'go mod tidy -v'"
+  exit 1
+fi
+
+cmd=$1
+
+# First we read in the list of all kustomize modules and their local locations. The data looks like:
+# sigs.k8s.io/kustomize/api /Users/you/src/sigs.k8s.io/kustomize/api
+# sigs.k8s.io/kustomize/cmd/config /Users/you/src/sigs.k8s.io/kustomize/cmd/config
+IFS=$'\n'
+modules=($(go list -m -f "{{.Path}} {{.Dir}}"))
+
+# Next we iterate over the lines, split apart the module name and local absolute path,
+# and add a relative-path replace statement to the go.mod. A replace statement will be added
+# for each Kustomize module, whether or not the current module uses it.
+IFS=" "
+replace_args=""
+for module in "${modules[@]}"; do
+  read -a module_data <<< $module
+  replace_path=$(realpath --relative-to=$(pwd) ${module_data[1]})
+  if [ $replace_path == . ] || [[ $replace_path == internal/* ]]; then
+    continue
+  fi
+  replace_args+=" -replace=${module_data[0]}=$replace_path"
+done
+
+go mod edit $replace_args
+
+# Now that the modules are pinned, we run the command passed to this script.
+bash -c "$cmd"
+
+# Finally we clean up by dropping the replace statements we added above.
+go mod edit $(sed 's/-replace/-dropreplace/g' <<< "$replace_args" | sed -E 's/=\.\.[^[:space:]]*//g')