Missing parentheses in LaTeX output

[jamesluke]

The LaTeX output of diff(sin(x)+cos(x), x, x)) is missing parentheses, producing incorrect output. The output looks like -sin(x) + cos(x), instead of the correct -(sin(x) + cos(x)). The internal representation is correct.

The output of repr(...) is '-(sin(x) + cos(x))'
The output of srepr(...) is "Mul(Integer(-1), Add(sin(Symbol('x')), cos(Symbol('x'))))"
The (incorrect) output of latex(...) is '- \\sin{\\left (x \\right )} + \\cos{\\left (x \\right )}'

[asmeurer]

I believe this is fixed in master

>>> latex(diff(sin(x)+cos(x), x, x))
'- (\\sin{\\left (x \\right )} + \\cos{\\left (x \\right )})'