39 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			JavaScript
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			39 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			JavaScript
		
	
	
		
			Executable File
		
	
	
	
	
| 'use strict';
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| 
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| Object.defineProperty(exports, "__esModule", {
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|   value: true
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| });
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| exports.default = extractValueFromUnaryExpression;
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| /**
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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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| function extractValueFromUnaryExpression(value) {
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|   // eslint-disable-next-line global-require
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|   var getValue = require('.').default;
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|   var operator = value.operator,
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|       argument = value.argument;
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| 
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| 
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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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| } |