Yes, such an expression exists in French but it is not mainstream and won’t be understood by everyone.
It means to be duped, to fail something, see for example this page and wikipedia.
Beware that the same expression might be used with different meanings, for example to tell what hot beverage you like :
– Tu veux un café ?
– Non merci, moi je suis chocolat.
It might also be used to tell you wear something color chocolate, or that your hairs or your skin has the same color.
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