Use echo command in mswin platform

[hsbt]

@kddnewton test_InterpolatedXStringNode is failed with mswin platform because printf is not provided on native windows console.

  1) Error:
Prism::TestCompilePrism#test_InterpolatedXStringNode:
Errno::ENOENT: No such file or directory - printf 100
    <compiled>:2:in ``'
    <compiled>:2:in `<class:TestCompilePrism>'
    <compiled>:1:in `<compiled>'
    C:/Users/hsbt/source/repos/ruby/ruby/test/ruby/test_compile_prism.rb:2439:in `eval'
    C:/Users/hsbt/source/repos/ruby/ruby/test/ruby/test_compile_prism.rb:2439:in `compare_eval'
    C:/Users/hsbt/source/repos/ruby/ruby/test/ruby/test_compile_prism.rb:2453:in `assert_prism_eval'
    C:/Users/hsbt/source/repos/ruby/ruby/test/ruby/test_compile_prism.rb:712:in `test_InterpolatedXStringNode'

I'm not sure why it doesn't use echo command same as first assertion.

[nurse]

Why this test executes printf command? I think just comparing with fixed string is more reasonable and faster.

[nobu]

This assertion seems nothing different from the immediately above from the point of parser.

Suggested change

	if /mswin|ucrt/ =~ RUBY_PLATFORM
	assert_prism_eval('`echo #{"100"}`')
	else
	assert_prism_eval('`printf #{"100"}`')
	end

[nobu]

Sorry, misread.
#{1} and #{"100"}.

I don't think there is a reason to use a different command.

Suggested change

	if /mswin|ucrt/ =~ RUBY_PLATFORM
	assert_prism_eval('`echo #{"100"}`')
	else
	assert_prism_eval('`printf #{"100"}`')
	end
	assert_prism_eval('`echo #{"100"}`')

[kddnewton]

Oh I didn't realize this test had been written like this. I don't think we should do any kind of external command here, the point is parsing. We should define def `(command); command; end so that it just returns the string.

[hsbt]

@kddnewton I'm going to merge this with simple replacement.

[kddnewton]

Sounds good, thanks! I'll make another pass to define `