function checkSpacingBeforeFirstToken(node) {
			const firstToken = node && sourceCode.getFirstToken(node);

			if (firstToken && firstToken.type === "Keyword") {
				checkSpacingBefore(firstToken);
			}
		}
Reports the first token of a given node if the first token is a keyword
and usage of spacing followed by the token is invalid.

This is used for unary operators (e.g. `typeof`), `function`, and `super`.
Other rules are handling usage of spacing preceded by those keywords.
@param {ASTNode|null} node A node to report.
@returns {void}