scripts/with-go-mod.sh: use symlink instead of -modfile

While the "-modfile=vendor.mod" is slightly more correct, using a
symlink allows for most of the go tools to work "as usual", just
without an acual `go.mod` being committed in the repository.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

scripts/docs/generate-man.sh

@@ -7,15 +7,15 @@ set -eu
 if ! command -v "$GO_MD2MAN" > /dev/null; then
   (
     set -x
-    go build -mod=vendor -modfile=vendor.mod -o ./build/tools/go-md2man ./vendor/github.com/cpuguy83/go-md2man/v2
+    go build -mod=vendor -o ./build/tools/go-md2man ./vendor/github.com/cpuguy83/go-md2man/v2
   )
   GO_MD2MAN=$(realpath ./build/tools/go-md2man)
 fi
 
 mkdir -p man/man1
 (
   set -x
-  go run -mod=vendor -modfile=vendor.mod -tags manpages ./man/generate.go --source "./man/src" --target "./man/man1"
+  go run -mod=vendor -tags manpages ./man/generate.go --source "./man/src" --target "./man/man1"
 )
 
 (

scripts/docs/generate-md.sh

@@ -4,7 +4,7 @@ set -eu
 
 (
   set -x
-  go run -mod=vendor -modfile=vendor.mod -tags docsgen ./docs/generate/generate.go --formats md --source "./docs/reference/commandline" --target "./docs/reference/commandline"
+  go run -mod=vendor -tags docsgen ./docs/generate/generate.go --formats md --source "./docs/reference/commandline" --target "./docs/reference/commandline"
 )
 
 # remove generated help.md file

scripts/docs/generate-yaml.sh

@@ -4,4 +4,4 @@ set -eu
 
 mkdir -p docs/yaml
 set -x
-go run -mod=vendor -modfile=vendor.mod -tags docsgen ./docs/generate/generate.go --formats yaml --source "./docs/reference/commandline" --target "./docs/yaml"
+go run -mod=vendor -tags docsgen ./docs/generate/generate.go --formats yaml --source "./docs/reference/commandline" --target "./docs/yaml"

scripts/vendor

@@ -14,7 +14,7 @@ if [ -z "$TYP" ]; then
 fi
 
 update() {
-  (set -x ; go mod tidy -modfile=vendor.mod; go mod vendor -modfile=vendor.mod)
+  (set -x ; go mod tidy; go mod vendor)
 }
 
 validate() {
@@ -31,7 +31,7 @@ outdated() {
     echo "go-mod-outdated not found. Install with 'go install github.com/psampaz/go-mod-outdated@v0.8.0'"
     exit 1
   fi
-  (set -x ; go list -mod=vendor -mod=readonly -modfile=vendor.mod -u -m -json all | go-mod-outdated -update -direct)
+  (set -x ; go list -mod=vendor -mod=readonly -u -m -json all | go-mod-outdated -update -direct)
 }
 
 case $TYP in

scripts/with-go-mod.sh

@@ -6,28 +6,40 @@
 # when the command is finished. This script should be dropped when this
 # repository is a proper Go module with a permanent go.mod.
 
-set -e
+set -euo pipefail
 
 SCRIPTDIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 ROOTDIR="$(cd "${SCRIPTDIR}/.." && pwd)"
 
-if test -e "${ROOTDIR}/go.mod"; then
-	{
-		scriptname=$(basename "$0")
-		cat >&2 <<- EOF
-			$scriptname: WARN: go.mod exists in the repository root!
-			$scriptname: WARN: Using your go.mod instead of our generated version -- this may misbehave!
-		EOF
-	} >&2
-else
+cleanup_paths=""
+create_symlink() {
+	local target="$1"
+	local link="$2"
+
+	pushd "${ROOTDIR}" > /dev/null
+	trap 'popd > /dev/null' RETURN
+
+	if [ -L "$link" ] && [ "$(readlink "$link")" = "$target" ]; then
+		# symlink already present; we're done
+		return
+	fi
+
+	if [ -e "$link" ]; then
+		echo "$(basename "$0"): WARN: $link exists but is not the expected symlink!" >&2
+		echo "$(basename "$0"): WARN: Using your version instead of our generated version -- this may misbehave!" >&2
+		return
+	fi
+
 	set -x
+	ln -s "$target" "$link"
+	cleanup_paths="$cleanup_paths ${ROOTDIR}/$link"
+}
 
-	tee "${ROOTDIR}/go.mod" >&2 <<- EOF
-		module github.com/docker/cli
+create_symlink "vendor.mod" "go.mod"
+create_symlink "vendor.sum" "go.sum"
 
-		go 1.23.0
-	EOF
-	trap 'rm -f "${ROOTDIR}/go.mod"' EXIT
+if [ -n "$cleanup_paths" ]; then
+	trap 'rm -f'"$cleanup_paths" EXIT
 fi
 
 GO111MODULE=on GOTOOLCHAIN=local "$@"