Small tool to report the size of Go packages in the GopherJS-compiled file

analyze-gopherjs

#!/usr/bin/perl

# This script can be used to see the size of each Go package
# in the JavaScript file complied by GopherJS.
#
# Run:
#
#     ./analyze-gopherjs client.js
#
# to analyze client.js file, or:
#
#     ./analyze-gopherjs client.js | grep http
#
# to just show the lines containing 'http' pacakge name.

use strict;

my $size = {};
my $total = 0;

my $file = $ARGV[0];
if ($file eq '') {
	print "Usage: $0 <path/to/compiled.js>\n";
	exit(1);
}

open(IN, $file) or die $!;
while (my $line = <IN>) {
	if ($line =~ m/^\$packages\["(.*?)"\]=/) {
		$size->{$1} = length($line);
		$total += $size->{$1};
	}
}
close IN;

foreach my $pkg (sort { $size->{$b} <=> $size->{$a} } keys %$size) {
	my $percent = $size->{$pkg} / $total * 100;
	$percent = int($percent * 100) / 100;
	print $pkg, " => ", $size->{$pkg}, " bytes ($percent%)\n";
}

Thank you, this was really helpful!