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