session-ios/Signal/translations/bin/auto-genstrings

#!/bin/bash
TARGETS="Signal/src ../SignalServiceKit/src Pods/JSQMessagesViewController"
TMP="$(mktemp -d)"
STRINGFILE="Signal/translations/en.lproj/Localizable.strings"

# Make sure we are in the right place
if [ ! -d "Signal/src" ]; then
  echo "Please run this tool from the repository's base directory"
  exit 1
fi

# Search directories for .m & .h files and collect string definitions with genstrings
find $TARGETS -name "*.m" -print0 -name "*.h" -print0 | xargs -0 genstrings -o $TMP

# We have to convert the old and new .strings files to UTF-8 in order to deal with them
OLDUTF8=$(iconv -f UTF-16 -t UTF-8 $STRINGFILE)
NEWUTF8=$(iconv -f UTF-16 -t UTF-8 $TMP/Localizable.strings)

# Let's merge the old with the new .strings file:
#	1. Select old string definition lines
#	2. Setup field separators
#	3. Read old string definitions as associative array
#	4. In new file, if possible, insert old definition
#	5. Add separator and semicolon only for string definition lines
#	6. Convert output back to UTF-16 to final location
echo "$OLDUTF8" | grep -Eo '^".*"' | \
	awk 'BEGIN {FS = "[ ]*=[ ]*"; OFS = ""} \
		NR == FNR {a[$1] = $2; next} \
		{$2 = ($1 in a ? a[$1] : $2); \
		if($2 ~ /"[;]*$/){$2 = " = "$2}; \
		if($2 ~ /"$/){$2 = $2";"}; \
		print}' - <(echo "$NEWUTF8") | \
	iconv -f UTF-8 -t UTF-16 > $STRINGFILE