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					326 lines
				
				11 KiB
			
		
		
			
		
	
	
					326 lines
				
				11 KiB
			| 
								 
											4 years ago
										 
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								/**
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								 * Copyright (c) 2014-present, Facebook, Inc.
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								 *
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								 * This source code is licensed under the MIT license found in the
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								 * LICENSE file in the root directory of this source tree.
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								 */
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								"use strict";
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								var _interopRequireWildcard = require("@babel/runtime/helpers/interopRequireWildcard");
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								var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
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								var _assert = _interopRequireDefault(require("assert"));
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								var _hoist = require("./hoist");
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								var _emit = require("./emit");
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								var _replaceShorthandObjectMethod = _interopRequireDefault(require("./replaceShorthandObjectMethod"));
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								var util = _interopRequireWildcard(require("./util"));
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								exports.getVisitor = function (_ref) {
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								  var t = _ref.types;
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								  return {
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								    Method: function Method(path, state) {
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								      var node = path.node;
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								      if (!shouldRegenerate(node, state)) return;
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								      var container = t.functionExpression(null, [], t.cloneNode(node.body, false), node.generator, node.async);
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								      path.get("body").set("body", [t.returnStatement(t.callExpression(container, []))]); // Regardless of whether or not the wrapped function is a an async method
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								      // or generator the outer function should not be
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								      node.async = false;
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								      node.generator = false; // Unwrap the wrapper IIFE's environment so super and this and such still work.
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								      path.get("body.body.0.argument.callee").unwrapFunctionEnvironment();
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								    },
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								    Function: {
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								      exit: util.wrapWithTypes(t, function (path, state) {
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								        var node = path.node;
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								        if (!shouldRegenerate(node, state)) return; // if this is an ObjectMethod, we need to convert it to an ObjectProperty
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								        path = (0, _replaceShorthandObjectMethod["default"])(path);
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								        node = path.node;
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								        var contextId = path.scope.generateUidIdentifier("context");
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								        var argsId = path.scope.generateUidIdentifier("args");
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								        path.ensureBlock();
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								        var bodyBlockPath = path.get("body");
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								        if (node.async) {
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								          bodyBlockPath.traverse(awaitVisitor);
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								        }
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								        bodyBlockPath.traverse(functionSentVisitor, {
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								          context: contextId
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								        });
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								        var outerBody = [];
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								        var innerBody = [];
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								        bodyBlockPath.get("body").forEach(function (childPath) {
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								          var node = childPath.node;
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								          if (t.isExpressionStatement(node) && t.isStringLiteral(node.expression)) {
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								            // Babylon represents directives like "use strict" as elements
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								            // of a bodyBlockPath.node.directives array, but they could just
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								            // as easily be represented (by other parsers) as traditional
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								            // string-literal-valued expression statements, so we need to
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								            // handle that here. (#248)
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								            outerBody.push(node);
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								          } else if (node && node._blockHoist != null) {
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								            outerBody.push(node);
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								          } else {
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								            innerBody.push(node);
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								          }
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								        });
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								        if (outerBody.length > 0) {
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								          // Only replace the inner body if we actually hoisted any statements
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								          // to the outer body.
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								          bodyBlockPath.node.body = innerBody;
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								        }
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								        var outerFnExpr = getOuterFnExpr(path); // Note that getOuterFnExpr has the side-effect of ensuring that the
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								        // function has a name (so node.id will always be an Identifier), even
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								        // if a temporary name has to be synthesized.
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								        t.assertIdentifier(node.id);
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								        var innerFnId = t.identifier(node.id.name + "$"); // Turn all declarations into vars, and replace the original
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								        // declarations with equivalent assignment expressions.
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								        var vars = (0, _hoist.hoist)(path);
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								        var context = {
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								          usesThis: false,
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								          usesArguments: false,
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								          getArgsId: function getArgsId() {
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								            return t.clone(argsId);
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								          }
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								        };
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								        path.traverse(argumentsThisVisitor, context);
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								        if (context.usesArguments) {
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								          vars = vars || t.variableDeclaration("var", []);
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								          vars.declarations.push(t.variableDeclarator(t.clone(argsId), t.identifier("arguments")));
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								        }
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								        var emitter = new _emit.Emitter(contextId);
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								        emitter.explode(path.get("body"));
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								        if (vars && vars.declarations.length > 0) {
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								          outerBody.push(vars);
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								        }
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								        var wrapArgs = [emitter.getContextFunction(innerFnId)];
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								        var tryLocsList = emitter.getTryLocsList();
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								        if (node.generator) {
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								          wrapArgs.push(outerFnExpr);
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								        } else if (context.usesThis || tryLocsList || node.async) {
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								          // Async functions that are not generators don't care about the
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								          // outer function because they don't need it to be marked and don't
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								          // inherit from its .prototype.
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								          wrapArgs.push(t.nullLiteral());
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								        }
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								        if (context.usesThis) {
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								          wrapArgs.push(t.thisExpression());
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								        } else if (tryLocsList || node.async) {
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								          wrapArgs.push(t.nullLiteral());
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								        }
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								        if (tryLocsList) {
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								          wrapArgs.push(tryLocsList);
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								        } else if (node.async) {
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								          wrapArgs.push(t.nullLiteral());
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								        }
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								        if (node.async) {
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								          // Rename any locally declared "Promise" variable,
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								          // to use the global one.
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								          var currentScope = path.scope;
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								          do {
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								            if (currentScope.hasOwnBinding("Promise")) currentScope.rename("Promise");
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								          } while (currentScope = currentScope.parent);
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								          wrapArgs.push(t.identifier("Promise"));
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								        }
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								        var wrapCall = t.callExpression(util.runtimeProperty(node.async ? "async" : "wrap"), wrapArgs);
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								        outerBody.push(t.returnStatement(wrapCall));
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								        node.body = t.blockStatement(outerBody); // We injected a few new variable declarations (for every hoisted var),
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								        // so we need to add them to the scope.
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								        path.get("body.body").forEach(function (p) {
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								          return p.scope.registerDeclaration(p);
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								        });
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								        var oldDirectives = bodyBlockPath.node.directives;
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								        if (oldDirectives) {
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								          // Babylon represents directives like "use strict" as elements of
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								          // a bodyBlockPath.node.directives array. (#248)
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								          node.body.directives = oldDirectives;
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								        }
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								        var wasGeneratorFunction = node.generator;
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								        if (wasGeneratorFunction) {
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								          node.generator = false;
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								        }
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								        if (node.async) {
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								          node.async = false;
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								        }
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								        if (wasGeneratorFunction && t.isExpression(node)) {
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								          util.replaceWithOrRemove(path, t.callExpression(util.runtimeProperty("mark"), [node]));
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								          path.addComment("leading", "#__PURE__");
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								        }
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								        var insertedLocs = emitter.getInsertedLocs();
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								        path.traverse({
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								          NumericLiteral: function NumericLiteral(path) {
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								            if (!insertedLocs.has(path.node)) {
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								              return;
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								            }
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								            path.replaceWith(t.numericLiteral(path.node.value));
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								          }
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								        }); // Generators are processed in 'exit' handlers so that regenerator only has to run on
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								        // an ES5 AST, but that means traversal will not pick up newly inserted references
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								        // to things like 'regeneratorRuntime'. To avoid this, we explicitly requeue.
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								        path.requeue();
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								      })
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								    }
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								  };
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								}; // Check if a node should be transformed by regenerator
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								function shouldRegenerate(node, state) {
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								  if (node.generator) {
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								    if (node.async) {
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								      // Async generator
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								      return state.opts.asyncGenerators !== false;
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								    } else {
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								      // Plain generator
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								      return state.opts.generators !== false;
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								    }
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								  } else if (node.async) {
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								    // Async function
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								    return state.opts.async !== false;
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								  } else {
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								    // Not a generator or async function.
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								    return false;
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								  }
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								} // Given a NodePath for a Function, return an Expression node that can be
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								// used to refer reliably to the function object from inside the function.
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								// This expression is essentially a replacement for arguments.callee, with
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								// the key advantage that it works in strict mode.
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								function getOuterFnExpr(funPath) {
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								  var t = util.getTypes();
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								  var node = funPath.node;
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								  t.assertFunction(node);
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								 | 
							
								
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								 | 
							
								  if (!node.id) {
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								 | 
							
								    // Default-exported function declarations, and function expressions may not
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								    // have a name to reference, so we explicitly add one.
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								 | 
							
								    node.id = funPath.scope.parent.generateUidIdentifier("callee");
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								 | 
							
								  }
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						||
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								 | 
							
								
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								 | 
							
								  if (node.generator && // Non-generator functions don't need to be marked.
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								 | 
							
								  t.isFunctionDeclaration(node)) {
							 | 
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								 | 
							
								    // Return the identifier returned by runtime.mark(<node.id>).
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						||
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								 | 
							
								    return getMarkedFunctionId(funPath);
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						||
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								 | 
							
								  }
							 | 
						||
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								 | 
							
								
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						||
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								 | 
							
								  return t.clone(node.id);
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						||
| 
								 | 
							
								}
							 | 
						||
| 
								 | 
							
								
							 | 
						||
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								 | 
							
								var markInfo = new WeakMap();
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						||
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								 | 
							
								
							 | 
						||
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								 | 
							
								function getMarkInfo(node) {
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						||
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								 | 
							
								  if (!markInfo.has(node)) {
							 | 
						||
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								 | 
							
								    markInfo.set(node, {});
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								 | 
							
								  }
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								 | 
							
								
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								 | 
							
								  return markInfo.get(node);
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						||
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								 | 
							
								}
							 | 
						||
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								 | 
							
								
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								 | 
							
								function getMarkedFunctionId(funPath) {
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						||
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								 | 
							
								  var t = util.getTypes();
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						||
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								 | 
							
								  var node = funPath.node;
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						||
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								 | 
							
								  t.assertIdentifier(node.id);
							 | 
						||
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								 | 
							
								  var blockPath = funPath.findParent(function (path) {
							 | 
						||
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								 | 
							
								    return path.isProgram() || path.isBlockStatement();
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						||
| 
								 | 
							
								  });
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								  if (!blockPath) {
							 | 
						||
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								 | 
							
								    return node.id;
							 | 
						||
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								 | 
							
								  }
							 | 
						||
| 
								 | 
							
								
							 | 
						||
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								 | 
							
								  var block = blockPath.node;
							 | 
						||
| 
								 | 
							
								
							 | 
						||
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								 | 
							
								  _assert["default"].ok(Array.isArray(block.body));
							 | 
						||
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								 | 
							
								
							 | 
						||
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								 | 
							
								  var info = getMarkInfo(block);
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								  if (!info.decl) {
							 | 
						||
| 
								 | 
							
								    info.decl = t.variableDeclaration("var", []);
							 | 
						||
| 
								 | 
							
								    blockPath.unshiftContainer("body", info.decl);
							 | 
						||
| 
								 | 
							
								    info.declPath = blockPath.get("body.0");
							 | 
						||
| 
								 | 
							
								  }
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								  _assert["default"].strictEqual(info.declPath.node, info.decl); // Get a new unique identifier for our marked variable.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								  var markedId = blockPath.scope.generateUidIdentifier("marked");
							 | 
						||
| 
								 | 
							
								  var markCallExp = t.callExpression(util.runtimeProperty("mark"), [t.clone(node.id)]);
							 | 
						||
| 
								 | 
							
								  var index = info.decl.declarations.push(t.variableDeclarator(markedId, markCallExp)) - 1;
							 | 
						||
| 
								 | 
							
								  var markCallExpPath = info.declPath.get("declarations." + index + ".init");
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								  _assert["default"].strictEqual(markCallExpPath.node, markCallExp);
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								  markCallExpPath.addComment("leading", "#__PURE__");
							 | 
						||
| 
								 | 
							
								  return t.clone(markedId);
							 | 
						||
| 
								 | 
							
								}
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								var argumentsThisVisitor = {
							 | 
						||
| 
								 | 
							
								  "FunctionExpression|FunctionDeclaration|Method": function FunctionExpressionFunctionDeclarationMethod(path) {
							 | 
						||
| 
								 | 
							
								    path.skip();
							 | 
						||
| 
								 | 
							
								  },
							 | 
						||
| 
								 | 
							
								  Identifier: function Identifier(path, state) {
							 | 
						||
| 
								 | 
							
								    if (path.node.name === "arguments" && util.isReference(path)) {
							 | 
						||
| 
								 | 
							
								      util.replaceWithOrRemove(path, state.getArgsId());
							 | 
						||
| 
								 | 
							
								      state.usesArguments = true;
							 | 
						||
| 
								 | 
							
								    }
							 | 
						||
| 
								 | 
							
								  },
							 | 
						||
| 
								 | 
							
								  ThisExpression: function ThisExpression(path, state) {
							 | 
						||
| 
								 | 
							
								    state.usesThis = true;
							 | 
						||
| 
								 | 
							
								  }
							 | 
						||
| 
								 | 
							
								};
							 | 
						||
| 
								 | 
							
								var functionSentVisitor = {
							 | 
						||
| 
								 | 
							
								  MetaProperty: function MetaProperty(path) {
							 | 
						||
| 
								 | 
							
								    var node = path.node;
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								    if (node.meta.name === "function" && node.property.name === "sent") {
							 | 
						||
| 
								 | 
							
								      var t = util.getTypes();
							 | 
						||
| 
								 | 
							
								      util.replaceWithOrRemove(path, t.memberExpression(t.clone(this.context), t.identifier("_sent")));
							 | 
						||
| 
								 | 
							
								    }
							 | 
						||
| 
								 | 
							
								  }
							 | 
						||
| 
								 | 
							
								};
							 | 
						||
| 
								 | 
							
								var awaitVisitor = {
							 | 
						||
| 
								 | 
							
								  Function: function Function(path) {
							 | 
						||
| 
								 | 
							
								    path.skip(); // Don't descend into nested function scopes.
							 | 
						||
| 
								 | 
							
								  },
							 | 
						||
| 
								 | 
							
								  AwaitExpression: function AwaitExpression(path) {
							 | 
						||
| 
								 | 
							
								    var t = util.getTypes(); // Convert await expressions to yield expressions.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								    var argument = path.node.argument; // Transforming `await x` to `yield regeneratorRuntime.awrap(x)`
							 | 
						||
| 
								 | 
							
								    // causes the argument to be wrapped in such a way that the runtime
							 | 
						||
| 
								 | 
							
								    // can distinguish between awaited and merely yielded values.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								    util.replaceWithOrRemove(path, t.yieldExpression(t.callExpression(util.runtimeProperty("awrap"), [argument]), false));
							 | 
						||
| 
								 | 
							
								  }
							 | 
						||
| 
								 | 
							
								};
							 |