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- "use strict";
-
- var util = _interopRequireWildcard(require("./util"));
-
- function _interopRequireWildcard(obj) { if (obj && obj.__esModule) { return obj; } else { var newObj = {}; if (obj != null) { for (var key in obj) { if (Object.prototype.hasOwnProperty.call(obj, key)) { var desc = Object.defineProperty && Object.getOwnPropertyDescriptor ? Object.getOwnPropertyDescriptor(obj, key) : {}; if (desc.get || desc.set) { Object.defineProperty(newObj, key, desc); } else { newObj[key] = obj[key]; } } } } newObj["default"] = obj; return newObj; } }
-
- /**
- * Copyright (c) 2014-present, Facebook, Inc.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
- var hasOwn = Object.prototype.hasOwnProperty; // The hoist function takes a FunctionExpression or FunctionDeclaration
- // and replaces any Declaration nodes in its body with assignments, then
- // returns a VariableDeclaration containing just the names of the removed
- // declarations.
-
- exports.hoist = function (funPath) {
- var t = util.getTypes();
- t.assertFunction(funPath.node);
- var vars = {};
-
- function varDeclToExpr(_ref, includeIdentifiers) {
- var vdec = _ref.node,
- scope = _ref.scope;
- t.assertVariableDeclaration(vdec); // TODO assert.equal(vdec.kind, "var");
-
- var exprs = [];
- vdec.declarations.forEach(function (dec) {
- // Note: We duplicate 'dec.id' here to ensure that the variable declaration IDs don't
- // have the same 'loc' value, since that can make sourcemaps and retainLines behave poorly.
- vars[dec.id.name] = t.identifier(dec.id.name); // Remove the binding, to avoid "duplicate declaration" errors when it will
- // be injected again.
-
- scope.removeBinding(dec.id.name);
-
- if (dec.init) {
- exprs.push(t.assignmentExpression("=", dec.id, dec.init));
- } else if (includeIdentifiers) {
- exprs.push(dec.id);
- }
- });
- if (exprs.length === 0) return null;
- if (exprs.length === 1) return exprs[0];
- return t.sequenceExpression(exprs);
- }
-
- funPath.get("body").traverse({
- VariableDeclaration: {
- exit: function exit(path) {
- var expr = varDeclToExpr(path, false);
-
- if (expr === null) {
- path.remove();
- } else {
- // We don't need to traverse this expression any further because
- // there can't be any new declarations inside an expression.
- util.replaceWithOrRemove(path, t.expressionStatement(expr));
- } // Since the original node has been either removed or replaced,
- // avoid traversing it any further.
-
-
- path.skip();
- }
- },
- ForStatement: function ForStatement(path) {
- var init = path.get("init");
-
- if (init.isVariableDeclaration()) {
- util.replaceWithOrRemove(init, varDeclToExpr(init, false));
- }
- },
- ForXStatement: function ForXStatement(path) {
- var left = path.get("left");
-
- if (left.isVariableDeclaration()) {
- util.replaceWithOrRemove(left, varDeclToExpr(left, true));
- }
- },
- FunctionDeclaration: function FunctionDeclaration(path) {
- var node = path.node;
- vars[node.id.name] = node.id;
- var assignment = t.expressionStatement(t.assignmentExpression("=", t.clone(node.id), t.functionExpression(path.scope.generateUidIdentifierBasedOnNode(node), node.params, node.body, node.generator, node.expression)));
-
- if (path.parentPath.isBlockStatement()) {
- // Insert the assignment form before the first statement in the
- // enclosing block.
- path.parentPath.unshiftContainer("body", assignment); // Remove the function declaration now that we've inserted the
- // equivalent assignment form at the beginning of the block.
-
- path.remove();
- } else {
- // If the parent node is not a block statement, then we can just
- // replace the declaration with the equivalent assignment form
- // without worrying about hoisting it.
- util.replaceWithOrRemove(path, assignment);
- } // Remove the binding, to avoid "duplicate declaration" errors when it will
- // be injected again.
-
-
- path.scope.removeBinding(node.id.name); // Don't hoist variables out of inner functions.
-
- path.skip();
- },
- FunctionExpression: function FunctionExpression(path) {
- // Don't descend into nested function expressions.
- path.skip();
- },
- ArrowFunctionExpression: function ArrowFunctionExpression(path) {
- // Don't descend into nested function expressions.
- path.skip();
- }
- });
- var paramNames = {};
- funPath.get("params").forEach(function (paramPath) {
- var param = paramPath.node;
-
- if (t.isIdentifier(param)) {
- paramNames[param.name] = param;
- } else {// Variables declared by destructuring parameter patterns will be
- // harmlessly re-declared.
- }
- });
- var declarations = [];
- Object.keys(vars).forEach(function (name) {
- if (!hasOwn.call(paramNames, name)) {
- declarations.push(t.variableDeclarator(vars[name], null));
- }
- });
-
- if (declarations.length === 0) {
- return null; // Be sure to handle this case!
- }
-
- return t.variableDeclaration("var", declarations);
- };
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