Fix dump/load float leteral evaluate to infinity

Example:

  # example.rb
  p(2e308)
  p(-2e308)

  Good:

    $ bin/mruby example.rb
    inf
    -inf

  Bad:

    $ bin/mrbc example.rb
    $ bin/mruby -b example.mrb
    0
    -0

Cause:

  Float infinity representation is `inf` on dump and it is converted by
  corresponding `String#to_f` on load.

Treatment:

  - Introduce new representations (`i`: +infinity, `I`: -infinity)
  - Allow old representations (`inf`, `-inf`, `infinity`, `-infinity`) too
  - Raise error for unknown representations (use corresponding `Kernel#Float`)

1 files changed, 7 insertions, 0 deletions

diff --git a/mrbgems/mruby-bin-mruby/bintest/mruby.rb b/mrbgems/mruby-bin-mruby/bintest/mruby.rb
index a7fb63fa2..f3c7d8761 100644
--- a/mrbgems/mruby-bin-mruby/bintest/mruby.rb
+++ b/mrbgems/mruby-bin-mruby/bintest/mruby.rb
@@ -31,6 +31,13 @@ assert '$0 value' do
   assert_equal '"-e"', `#{cmd('mruby')} -e #{shellquote('p $0')}`.chomp
 end
 
+assert('float literal') do
+  script, bin = Tempfile.new('test.rb'), Tempfile.new('test.mrb')
+  File.write script.path, 'p [3.21, 2e308.infinite?, -2e308.infinite?]'
+  system "#{cmd('mrbc')} -g -o #{bin.path} #{script.path}"
+  assert_equal "[3.21, 1, -1]", `#{cmd('mruby')} -b #{bin.path}`.chomp!
+end
+
 assert '__END__', '8.6' do
   script = Tempfile.new('test.rb')