I would expect isDoubleQuote: true here:

Before b"$var" does use a binary node, and the raw encapsed node does not include the b prefix.
From this commit, the binary encapsed nodes are no more into a binary node and the raw property includes the b prefix.
Next I will have to include the unicode property on encapsed nodes also, as explained here : https://github.com/glayzzle/php-parser/issues/147
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* Breaking Changes *
Before
b"$var"does use a binary node, and the raw encapsed node does not include thebprefix.From this commit, the binary encapsed nodes are no more into a binary node and the raw property includes the
bprefix.Next I will have to include the unicode property on encapsed nodes also, as explained here : https://github.com/glayzzle/php-parser/issues/147