69 lines
1.7 KiB
JavaScript
69 lines
1.7 KiB
JavaScript
"use strict";
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var util = require("../../../util");
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var t = require("../../../types");
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var hasDefaults = function (node) {
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for (var i = 0; i < node.params.length; i++) {
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if (t.isAssignmentPattern(node.params[i])) return true;
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}
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return false;
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};
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exports.Function = function (node, parent, scope) {
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if (!hasDefaults(node)) return;
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t.ensureBlock(node);
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var iife = false;
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var body = [];
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var argsIdentifier = t.identifier("arguments");
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argsIdentifier._ignoreAliasFunctions = true;
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var lastNonDefaultParam = 0;
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for (var i = 0; i < node.params.length; i++) {
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var param = node.params[i];
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if (!t.isAssignmentPattern(param)) {
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lastNonDefaultParam = +i + 1;
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continue;
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}
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var left = param.left;
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var right = param.right;
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node.params[i] = scope.generateUidIdentifier("x");
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// we're accessing a variable that's already defined within this function
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var localDeclar = scope.get(left.name, true);
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if (localDeclar !== left) {
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iife = true;
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}
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var defNode = util.template("default-parameter", {
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VARIABLE_NAME: left,
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DEFAULT_VALUE: right,
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ARGUMENT_KEY: t.literal(+i),
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ARGUMENTS: argsIdentifier
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}, true);
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defNode._blockHoist = node.params.length - i;
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body.push(defNode);
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}
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// we need to cut off all trailing default parameters
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node.params = node.params.slice(0, lastNonDefaultParam);
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if (iife) {
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var container = t.functionExpression(null, [], node.body, node.generator);
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container._aliasFunction = true;
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body.push(t.returnStatement(t.callExpression(container, [])));
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node.body = t.blockStatement(body);
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} else {
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node.body.body = body.concat(node.body.body);
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}
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};
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