%Q String literal with \0 delimiter is non-interpolatable

[andrykonchin]

This trick is used in the haml gem here. The issue was reported in sinatra/sinatra#2007.

How to reproduce:

1. Generate a source file with code snippet:

source_code = "%Q\0" + 'Hello #{a.strip}!' + "\0"
File.write("test.rb", source_code)

2. Run CRuby:

$ ruby test.rb
sinatra-test.rb:1:in `<main>': undefined local variable or method `a' for main:Object (NameError)

%QHello #{a.strip}!
           ^

So the string literal is interpolatable

3. Parse with Prism:

$ bin/parse sinatra-test.rb
@ ProgramNode (location: (1,0)-(1,21))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(1,21))
    └── body: (length: 1)
        └── @ StringNode (location: (1,0)-(1,21))
            ├── flags: ∅
            ├── opening_loc: (1,0)-(1,3) = "%Q\u0000"
            ├── content_loc: (1,3)-(1,20) = "Hello \#{a.strip}!"
            ├── closing_loc: (1,20)-(1,21) = "\u0000"
            └── unescaped: "Hello \#{a.strip}!"

The string literal is not interpolatable

[kddnewton]

Weird! I'll get it fixed.