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1 /**
2 * Copyright (c) Meta Platforms, Inc. and affiliates.
3 *
4 * This source code is licensed under the MIT license found in the
5 * LICENSE file in the root directory of this source tree.
6 */
7 'use strict';
8
9 function evalStringConcat(ast) {
10 switch (ast.type) {
11 case 'StringLiteral':
12 case 'Literal': // ESLint
13 return ast.value;
14 case 'BinaryExpression': // `+`
15 if (ast.operator !== '+') {
16 throw new Error('Unsupported binary operator ' + ast.operator);
17 }
18 return evalStringConcat(ast.left) + evalStringConcat(ast.right);
19 default:
20 throw new Error('Unsupported type ' + ast.type);
21 }
22 }
23 exports.evalStringConcat = evalStringConcat;
24
25 function evalStringAndTemplateConcat(ast, args) {
26 switch (ast.type) {
27 case 'StringLiteral':
28 return ast.value;
29 case 'BinaryExpression': // `+`
30 if (ast.operator !== '+') {
31 throw new Error('Unsupported binary operator ' + ast.operator);
32 }
33 return (
34 evalStringAndTemplateConcat(ast.left, args) +
35 evalStringAndTemplateConcat(ast.right, args)
36 );
37 case 'TemplateLiteral': {
38 let elements = [];
39 for (let i = 0; i < ast.quasis.length; i++) {
40 const elementNode = ast.quasis[i];
41 if (elementNode.type !== 'TemplateElement') {
42 throw new Error('Unsupported type ' + ast.type);
43 }
44 elements.push(elementNode.value.cooked);
45 }
46 args.push(...ast.expressions);
47 return elements.join('%s');
48 }
49 default:
50 // Anything that's not a string is interpreted as an argument.
51 args.push(ast);
52 return '%s';
53 }
54 }
55 exports.evalStringAndTemplateConcat = evalStringAndTemplateConcat;