lib/time: update to 2022g/2022g

Commit generated by update.bash.

For #22487.

Change-Id: I6a995a3baea7c511b9bd5155f81d8b8e2cdff09d
Reviewed-on: https://go-review.googlesource.com/c/go/+/455356
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>
Auto-Submit: Russ Cox <rsc@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>

1 files changed, 59 insertions, 11 deletions

diff --git a/lib/time/update.bash b/lib/time/update.bash
index d49127b275..48606b9de4 100755
--- a/lib/time/update.bash
+++ b/lib/time/update.bash
@@ -5,35 +5,83 @@
 
 # This script rebuilds the time zone files using files
 # downloaded from the ICANN/IANA distribution.
-# Consult https://www.iana.org/time-zones for the latest versions.
+#
+# To prepare an update for a new Go release,
+# consult https://www.iana.org/time-zones for the latest versions,
+# update CODE and DATA below, and then run
+#
+#	./update.bash -commit
+#
+# That will prepare the files and create the commit.
+#
+# To review such a commit (as the reviewer), use:
+#
+#	git codereview change NNNNNN   # CL number
+#	cd lib/time
+#	./update.bash
+#
+# If it prints "No updates needed.", then the generated files
+# in the CL match the update.bash in the CL.
 
 # Versions to use.
-CODE=2022f
-DATA=2022f
+CODE=2022g
+DATA=2022g
 
 set -e
+
+cd $(dirname $0)
 rm -rf work
 mkdir work
+go build -o work/mkzip mkzip.go # build now for correct paths in build errors
 cd work
 mkdir zoneinfo
-curl -L -O https://www.iana.org/time-zones/repository/releases/tzcode$CODE.tar.gz
-curl -L -O https://www.iana.org/time-zones/repository/releases/tzdata$DATA.tar.gz
+curl -sS -L -O https://www.iana.org/time-zones/repository/releases/tzcode$CODE.tar.gz
+curl -sS -L -O https://www.iana.org/time-zones/repository/releases/tzdata$DATA.tar.gz
 tar xzf tzcode$CODE.tar.gz
 tar xzf tzdata$DATA.tar.gz
 
-make CFLAGS=-DSTD_INSPIRED AWK=awk TZDIR=zoneinfo posix_only
+if ! make CFLAGS=-DSTD_INSPIRED AWK=awk TZDIR=zoneinfo posix_only >make.out 2>&1; then
+	cat make.out
+	exit 2
+fi
 
 cd zoneinfo
-rm -f ../../zoneinfo.zip
-zip -0 -r ../../zoneinfo.zip *
+../mkzip ../../zoneinfo.zip
 cd ../..
-
 go generate time/tzdata
 
-echo
+files="update.bash zoneinfo.zip ../../src/time/tzdata/zipdata.go"
+modified=true
+if git diff --quiet $files; then
+	modified=false
+fi
+
 if [ "$1" = "-work" ]; then
 	echo Left workspace behind in work/.
+	shift
 else
 	rm -rf work
 fi
-echo New time zone files in zoneinfo.zip.
+
+if ! $modified; then
+	echo No updates needed.
+	exit 0
+fi
+
+echo Updated for $CODE/$DATA: $files
+
+commitmsg="lib/time: update to $CODE/$DATA
+
+Commit generated by update.bash.
+
+For #22487.
+"
+
+if [ "$1" = "-commit" ]; then
+	echo "Creating commit. Run 'git reset HEAD^' to undo commit."
+	echo
+	git commit -m "$commitmsg" $files
+	echo
+	git log -n1 --stat
+	echo
+fi