47 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			47 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| "use strict";
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| 
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| exports.__esModule = true;
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| exports.default = _default;
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| 
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| /**
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|  * Fixes block-shadowed let/const bindings in Safari 10/11.
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|  * https://kangax.github.io/compat-table/es6/#test-let_scope_shadow_resolution
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|  */
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| function _default({
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|   types: t
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| }) {
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|   return {
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|     name: "transform-safari-block-shadowing",
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|     visitor: {
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|       VariableDeclarator(path) {
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|         // the issue only affects let and const bindings:
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|         const kind = path.parent.kind;
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|         if (kind !== "let" && kind !== "const") return; // ignore non-block-scoped bindings:
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| 
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|         const block = path.scope.block;
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|         if (t.isFunction(block) || t.isProgram(block)) return;
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|         const bindings = t.getOuterBindingIdentifiers(path.node.id);
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| 
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|         for (const name of Object.keys(bindings)) {
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|           let scope = path.scope; // ignore parent bindings (note: impossible due to let/const?)
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| 
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|           if (!scope.hasOwnBinding(name)) continue; // check if shadowed within the nearest function/program boundary
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| 
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|           while (scope = scope.parent) {
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|             if (scope.hasOwnBinding(name)) {
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|               path.scope.rename(name);
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|               break;
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|             }
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| 
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|             if (t.isFunction(scope.block) || t.isProgram(scope.block)) {
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|               break;
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|             }
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|           }
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|         }
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|       }
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| 
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|     }
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|   };
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| }
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| 
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| module.exports = exports.default; |