Detect misplaced equals sign

[Zash]

Sometimes when you meant to write

local x = fun()

you might accidentally the equals sign and end up with

local x fun()

Since this is equivalent to local x; fun();, and thus perfectly legal, it can be hard to notice this mistake.

Perhaps this is something luacheck could point out?

[alerque]

I'm not sure how this could be detected as a lint since it is perfectly valid code the other way too, but I'm open to contributions if anybody figures out how to do so.

[Nomarian]

IDK how luacheck works but its kind of checkable with a simple

if string.match"^%s*local%s+[%a_][%w_ ]* +[%a_][%w_]*(" then Warn"Possible missing assignment in line"

if you go line by line, which I imagine is the only possible case, because if everything is in a single line, it doesn't matter.

The code is technically correct, so something like lxsh works, a gmatch and filling a table allows you to create a conditional like

"local" followed by an identifier followed by a call

[arichard4]

Another possible non-function error case would be "local x = a" => "local x a".

Maybe the simplest and most general way to do this would be to lint against multiple statements on a single line. The most naive way of doing so would also bar doing so with explicit semicolons as well, which I think is fine.