function checkSpaceBeforeCaseBlock(node) {
			const cases = node.cases;
			let openingBrace;

			if (cases.length > 0) {
				openingBrace = sourceCode.getTokenBefore(cases[0]);
			} else {
				openingBrace = sourceCode.getLastToken(node, 1);
			}

			checkPrecedingSpace(openingBrace);
		}
Checks if the CaseBlock of an given SwitchStatement node has a preceding space.
@param {ASTNode} node The node of a SwitchStatement.
@returns {void} undefined.