32 lines
993 B
Plaintext
32 lines
993 B
Plaintext
/**
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* Extractor function for a UnaryExpression type value node.
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* A unary expression is an expression with a unary operator.
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* For example, !"foobar" will evaluate to false, so this will return false.
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*
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* @param - value - AST Value object with type `UnaryExpression`
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* @returns - The extracted value converted to correct type.
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*/
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export default function extractValueFromUnaryExpression(value) {
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// eslint-disable-next-line global-require
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const getValue = require('.').default;
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const { operator, argument } = value;
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switch (operator) {
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case '-':
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return -getValue(argument);
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case '+':
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return +getValue(argument); // eslint-disable-line no-implicit-coercion
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case '!':
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return !getValue(argument);
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case '~':
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return ~getValue(argument); // eslint-disable-line no-bitwise
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case 'delete':
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// I believe delete statements evaluate to true.
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return true;
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case 'typeof':
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case 'void':
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default:
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return undefined;
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}
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}
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