There's a typo in the _element_constructor_, revealed by the new doctesting implementation.

sage: McdJ = MacdonaldPolynomialsJ(QQ)
sage: s = SymmetricFunctions(McdJ.base_ring()).s()
sage: s._element_constructor(McdJ(s[2,1])
BOOM!

CC: @mwhansen

Component: combinatorics

Author: David Roe

Reviewer: Nathann Cohen, Nicolas M. Thiéry, David Loeffler

Merged: sage-5.0.beta12

Issue created by migration from https://trac.sagemath.org/ticket/12381