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-rw-r--r--node_modules/regenerator-transform/lib/hoist.js144
1 files changed, 144 insertions, 0 deletions
diff --git a/node_modules/regenerator-transform/lib/hoist.js b/node_modules/regenerator-transform/lib/hoist.js
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+++ b/node_modules/regenerator-transform/lib/hoist.js
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+"use strict";
+
+var _util = require("./util");
+
+var util = _interopRequireWildcard(_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)) newObj[key] = obj[key]; } } newObj.default = obj; return newObj; } }
+
+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.
+/**
+ * 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.
+ */
+
+exports.hoist = function (funPath) {
+ var t = util.getTypes();
+ t.assertFunction(funPath.node);
+
+ var vars = {};
+
+ function varDeclToExpr(vdec, includeIdentifiers) {
+ 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);
+
+ 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.node, 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.node.init;
+ if (t.isVariableDeclaration(init)) {
+ util.replaceWithOrRemove(path.get("init"), varDeclToExpr(init, false));
+ }
+ },
+
+ ForXStatement: function ForXStatement(path) {
+ var left = path.get("left");
+ if (left.isVariableDeclaration()) {
+ util.replaceWithOrRemove(left, varDeclToExpr(left.node, true));
+ }
+ },
+
+ FunctionDeclaration: function FunctionDeclaration(path) {
+ var node = path.node;
+ vars[node.id.name] = node.id;
+
+ var assignment = t.expressionStatement(t.assignmentExpression("=", 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);
+ }
+
+ // 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);
+}; \ No newline at end of file