Given the density of the jargon in LaTeX files, it's much more convenient to spell in batch mode, rather than in an interactive "would-you-like-to-correct-this-word-by-that-one" mode.
After brew install ispell and brew install aspell, I can spell check using one of
aspell -c -t file.tex
ispell -t file.tex
but both are interactive.
What is the non-interactive variation? ispell -l -t file.tex used to work, but this may have been an entirely different ispell (from MacPorts).
brew install aspellwithwhich aspellreporting/usr/local/bin/aspell. But I've suspected there are multiple programs dubbed{a,i}spell. – Calaf Oct 24 '17 at 19:04