release.bash: make work on Linux

Most releases of Linux use the GNU version of sed, while
most releases of macOS use the BSD version of sed.

For the -i flag, BSD always expects an argument,
while GNU expects an optional argument in a different format.

See https://www.freebsd.org/cgi/man.cgi?query=sed&sektion=&n=1
See https://www.gnu.org/software/sed/manual/html_node/Command_002dLine-Options.html#Command_002dLine-Options

Change-Id: Id0f472553c8583d427524f59b36c376d6bc28786
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/330869
Trust: Joe Tsai <joetsai@digital-static.net>
Reviewed-by: Damien Neil <dneil@google.com>

Author: dsnet

release.bash

@@ -63,14 +63,18 @@ git change release
 git sync
 
 # Create commit for actual release.
-sed -i "" -e "s/\(Minor *= *\)[0-9]*/\1$VERSION_MINOR/" internal/version/version.go
-sed -i "" -e "s/\(Patch *= *\)[0-9]*/\1$VERSION_PATCH/" internal/version/version.go
-sed -i "" -e "s/\(PreRelease *= *\)\"[^\"]*\"/\1\"$VERSION_PRERELEASE\"/" internal/version/version.go
+INPLACE='-i ""' # BSD version of sed expects argument after -i
+if [[ "$(sed --version)" == *"GNU"* ]]; then
+	INPLACE="-i" # GNU version of sed does not expect argument after -i
+fi
+sed $INPLACE -e "s/\(Minor *= *\)[0-9]*/\1$VERSION_MINOR/" internal/version/version.go
+sed $INPLACE -e "s/\(Patch *= *\)[0-9]*/\1$VERSION_PATCH/" internal/version/version.go
+sed $INPLACE -e "s/\(PreRelease *= *\)\"[^\"]*\"/\1\"$VERSION_PRERELEASE\"/" internal/version/version.go
 if ! [[ -z $GEN_VERSION ]]; then
-	sed -i "" -e "s/\(GenVersion *= *\)[0-9]*/\1$GEN_VERSION/" runtime/protoimpl/version.go
+	sed $INPLACE -e "s/\(GenVersion *= *\)[0-9]*/\1$GEN_VERSION/" runtime/protoimpl/version.go
 fi
 if ! [[ -z $MIN_VERSION ]]; then
-	sed -i "" -e "s/\(MinVersion *= *\)[0-9]*/\1$MIN_VERSION/" runtime/protoimpl/version.go
+	sed $INPLACE -e "s/\(MinVersion *= *\)[0-9]*/\1$MIN_VERSION/" runtime/protoimpl/version.go
 fi
 git commit -a -m "all: release $(version_string)"
 
@@ -80,7 +84,7 @@ go test -mod=vendor -timeout=60m -count=1 integration_test.go "$@" -buildRelease
 # Create commit to start development after release.
 VERSION_PRERELEASE="${VERSION_PRERELEASE}.devel" # append ".devel"
 VERSION_PRERELEASE="${VERSION_PRERELEASE#"."}"   # trim possible leading "."
-sed -i "" -e "s/\(PreRelease *= *\)\"[^\"]*\"/\1\"$VERSION_PRERELEASE\"/" internal/version/version.go
+sed $INPLACE -e "s/\(PreRelease *= *\)\"[^\"]*\"/\1\"$VERSION_PRERELEASE\"/" internal/version/version.go
 git commit -a -m "all: start $(version_string)"
 
 echo