You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
39 lines
1.1 KiB
39 lines
1.1 KiB
4 years ago
|
'use strict';
|
||
|
|
||
|
Object.defineProperty(exports, "__esModule", {
|
||
|
value: true
|
||
|
});
|
||
|
exports.default = extractValueFromUnaryExpression;
|
||
|
/**
|
||
|
* Extractor function for a UnaryExpression type value node.
|
||
|
* A unary expression is an expression with a unary operator.
|
||
|
* For example, !"foobar" will evaluate to false, so this will return false.
|
||
|
*
|
||
|
* @param - value - AST Value object with type `UnaryExpression`
|
||
|
* @returns - The extracted value converted to correct type.
|
||
|
*/
|
||
|
function extractValueFromUnaryExpression(value) {
|
||
|
// eslint-disable-next-line global-require
|
||
|
var getValue = require('./index.js').default;
|
||
|
var operator = value.operator,
|
||
|
argument = value.argument;
|
||
|
|
||
|
|
||
|
switch (operator) {
|
||
|
case '-':
|
||
|
return -getValue(argument);
|
||
|
case '+':
|
||
|
return +getValue(argument); // eslint-disable-line no-implicit-coercion
|
||
|
case '!':
|
||
|
return !getValue(argument);
|
||
|
case '~':
|
||
|
return ~getValue(argument); // eslint-disable-line no-bitwise
|
||
|
case 'delete':
|
||
|
// I believe delete statements evaluate to true.
|
||
|
return true;
|
||
|
case 'typeof':
|
||
|
case 'void':
|
||
|
default:
|
||
|
return undefined;
|
||
|
}
|
||
|
}
|