0.2.0 - Mid migration

web/node_modules/regenerator-transform/lib/emit.js

@@ -0,0 +1,959 @@
+"use strict";
+
+var _interopRequireWildcard = require("@babel/runtime/helpers/interopRequireWildcard");
+
+var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
+
+var _assert = _interopRequireDefault(require("assert"));
+
+var leap = _interopRequireWildcard(require("./leap"));
+
+var meta = _interopRequireWildcard(require("./meta"));
+
+var util = _interopRequireWildcard(require("./util"));
+
+/**
+ * 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;
+
+function Emitter(contextId) {
+  _assert["default"].ok(this instanceof Emitter);
+
+  util.getTypes().assertIdentifier(contextId); // Used to generate unique temporary names.
+
+  this.nextTempId = 0; // In order to make sure the context object does not collide with
+  // anything in the local scope, we might have to rename it, so we
+  // refer to it symbolically instead of just assuming that it will be
+  // called "context".
+
+  this.contextId = contextId; // An append-only list of Statements that grows each time this.emit is
+  // called.
+
+  this.listing = []; // A sparse array whose keys correspond to locations in this.listing
+  // that have been marked as branch/jump targets.
+
+  this.marked = [true];
+  this.insertedLocs = new Set(); // The last location will be marked when this.getDispatchLoop is
+  // called.
+
+  this.finalLoc = this.loc(); // A list of all leap.TryEntry statements emitted.
+
+  this.tryEntries = []; // Each time we evaluate the body of a loop, we tell this.leapManager
+  // to enter a nested loop context that determines the meaning of break
+  // and continue statements therein.
+
+  this.leapManager = new leap.LeapManager(this);
+}
+
+var Ep = Emitter.prototype;
+exports.Emitter = Emitter; // Offsets into this.listing that could be used as targets for branches or
+// jumps are represented as numeric Literal nodes. This representation has
+// the amazingly convenient benefit of allowing the exact value of the
+// location to be determined at any time, even after generating code that
+// refers to the location.
+
+Ep.loc = function () {
+  var l = util.getTypes().numericLiteral(-1);
+  this.insertedLocs.add(l);
+  return l;
+};
+
+Ep.getInsertedLocs = function () {
+  return this.insertedLocs;
+};
+
+Ep.getContextId = function () {
+  return util.getTypes().clone(this.contextId);
+}; // Sets the exact value of the given location to the offset of the next
+// Statement emitted.
+
+
+Ep.mark = function (loc) {
+  util.getTypes().assertLiteral(loc);
+  var index = this.listing.length;
+
+  if (loc.value === -1) {
+    loc.value = index;
+  } else {
+    // Locations can be marked redundantly, but their values cannot change
+    // once set the first time.
+    _assert["default"].strictEqual(loc.value, index);
+  }
+
+  this.marked[index] = true;
+  return loc;
+};
+
+Ep.emit = function (node) {
+  var t = util.getTypes();
+
+  if (t.isExpression(node)) {
+    node = t.expressionStatement(node);
+  }
+
+  t.assertStatement(node);
+  this.listing.push(node);
+}; // Shorthand for emitting assignment statements. This will come in handy
+// for assignments to temporary variables.
+
+
+Ep.emitAssign = function (lhs, rhs) {
+  this.emit(this.assign(lhs, rhs));
+  return lhs;
+}; // Shorthand for an assignment statement.
+
+
+Ep.assign = function (lhs, rhs) {
+  var t = util.getTypes();
+  return t.expressionStatement(t.assignmentExpression("=", t.cloneDeep(lhs), rhs));
+}; // Convenience function for generating expressions like context.next,
+// context.sent, and context.rval.
+
+
+Ep.contextProperty = function (name, computed) {
+  var t = util.getTypes();
+  return t.memberExpression(this.getContextId(), computed ? t.stringLiteral(name) : t.identifier(name), !!computed);
+}; // Shorthand for setting context.rval and jumping to `context.stop()`.
+
+
+Ep.stop = function (rval) {
+  if (rval) {
+    this.setReturnValue(rval);
+  }
+
+  this.jump(this.finalLoc);
+};
+
+Ep.setReturnValue = function (valuePath) {
+  util.getTypes().assertExpression(valuePath.value);
+  this.emitAssign(this.contextProperty("rval"), this.explodeExpression(valuePath));
+};
+
+Ep.clearPendingException = function (tryLoc, assignee) {
+  var t = util.getTypes();
+  t.assertLiteral(tryLoc);
+  var catchCall = t.callExpression(this.contextProperty("catch", true), [t.clone(tryLoc)]);
+
+  if (assignee) {
+    this.emitAssign(assignee, catchCall);
+  } else {
+    this.emit(catchCall);
+  }
+}; // Emits code for an unconditional jump to the given location, even if the
+// exact value of the location is not yet known.
+
+
+Ep.jump = function (toLoc) {
+  this.emitAssign(this.contextProperty("next"), toLoc);
+  this.emit(util.getTypes().breakStatement());
+}; // Conditional jump.
+
+
+Ep.jumpIf = function (test, toLoc) {
+  var t = util.getTypes();
+  t.assertExpression(test);
+  t.assertLiteral(toLoc);
+  this.emit(t.ifStatement(test, t.blockStatement([this.assign(this.contextProperty("next"), toLoc), t.breakStatement()])));
+}; // Conditional jump, with the condition negated.
+
+
+Ep.jumpIfNot = function (test, toLoc) {
+  var t = util.getTypes();
+  t.assertExpression(test);
+  t.assertLiteral(toLoc);
+  var negatedTest;
+
+  if (t.isUnaryExpression(test) && test.operator === "!") {
+    // Avoid double negation.
+    negatedTest = test.argument;
+  } else {
+    negatedTest = t.unaryExpression("!", test);
+  }
+
+  this.emit(t.ifStatement(negatedTest, t.blockStatement([this.assign(this.contextProperty("next"), toLoc), t.breakStatement()])));
+}; // Returns a unique MemberExpression that can be used to store and
+// retrieve temporary values. Since the object of the member expression is
+// the context object, which is presumed to coexist peacefully with all
+// other local variables, and since we just increment `nextTempId`
+// monotonically, uniqueness is assured.
+
+
+Ep.makeTempVar = function () {
+  return this.contextProperty("t" + this.nextTempId++);
+};
+
+Ep.getContextFunction = function (id) {
+  var t = util.getTypes();
+  return t.functionExpression(id || null
+  /*Anonymous*/
+  , [this.getContextId()], t.blockStatement([this.getDispatchLoop()]), false, // Not a generator anymore!
+  false // Nor an expression.
+  );
+}; // Turns this.listing into a loop of the form
+//
+//   while (1) switch (context.next) {
+//   case 0:
+//   ...
+//   case n:
+//     return context.stop();
+//   }
+//
+// Each marked location in this.listing will correspond to one generated
+// case statement.
+
+
+Ep.getDispatchLoop = function () {
+  var self = this;
+  var t = util.getTypes();
+  var cases = [];
+  var current; // If we encounter a break, continue, or return statement in a switch
+  // case, we can skip the rest of the statements until the next case.
+
+  var alreadyEnded = false;
+  self.listing.forEach(function (stmt, i) {
+    if (self.marked.hasOwnProperty(i)) {
+      cases.push(t.switchCase(t.numericLiteral(i), current = []));
+      alreadyEnded = false;
+    }
+
+    if (!alreadyEnded) {
+      current.push(stmt);
+      if (t.isCompletionStatement(stmt)) alreadyEnded = true;
+    }
+  }); // Now that we know how many statements there will be in this.listing,
+  // we can finally resolve this.finalLoc.value.
+
+  this.finalLoc.value = this.listing.length;
+  cases.push(t.switchCase(this.finalLoc, [// Intentionally fall through to the "end" case...
+  ]), // So that the runtime can jump to the final location without having
+  // to know its offset, we provide the "end" case as a synonym.
+  t.switchCase(t.stringLiteral("end"), [// This will check/clear both context.thrown and context.rval.
+  t.returnStatement(t.callExpression(this.contextProperty("stop"), []))]));
+  return t.whileStatement(t.numericLiteral(1), t.switchStatement(t.assignmentExpression("=", this.contextProperty("prev"), this.contextProperty("next")), cases));
+};
+
+Ep.getTryLocsList = function () {
+  if (this.tryEntries.length === 0) {
+    // To avoid adding a needless [] to the majority of runtime.wrap
+    // argument lists, force the caller to handle this case specially.
+    return null;
+  }
+
+  var t = util.getTypes();
+  var lastLocValue = 0;
+  return t.arrayExpression(this.tryEntries.map(function (tryEntry) {
+    var thisLocValue = tryEntry.firstLoc.value;
+
+    _assert["default"].ok(thisLocValue >= lastLocValue, "try entries out of order");
+
+    lastLocValue = thisLocValue;
+    var ce = tryEntry.catchEntry;
+    var fe = tryEntry.finallyEntry;
+    var locs = [tryEntry.firstLoc, // The null here makes a hole in the array.
+    ce ? ce.firstLoc : null];
+
+    if (fe) {
+      locs[2] = fe.firstLoc;
+      locs[3] = fe.afterLoc;
+    }
+
+    return t.arrayExpression(locs.map(function (loc) {
+      return loc && t.clone(loc);
+    }));
+  }));
+}; // All side effects must be realized in order.
+// If any subexpression harbors a leap, all subexpressions must be
+// neutered of side effects.
+// No destructive modification of AST nodes.
+
+
+Ep.explode = function (path, ignoreResult) {
+  var t = util.getTypes();
+  var node = path.node;
+  var self = this;
+  t.assertNode(node);
+  if (t.isDeclaration(node)) throw getDeclError(node);
+  if (t.isStatement(node)) return self.explodeStatement(path);
+  if (t.isExpression(node)) return self.explodeExpression(path, ignoreResult);
+
+  switch (node.type) {
+    case "Program":
+      return path.get("body").map(self.explodeStatement, self);
+
+    case "VariableDeclarator":
+      throw getDeclError(node);
+    // These node types should be handled by their parent nodes
+    // (ObjectExpression, SwitchStatement, and TryStatement, respectively).
+
+    case "Property":
+    case "SwitchCase":
+    case "CatchClause":
+      throw new Error(node.type + " nodes should be handled by their parents");
+
+    default:
+      throw new Error("unknown Node of type " + JSON.stringify(node.type));
+  }
+};
+
+function getDeclError(node) {
+  return new Error("all declarations should have been transformed into " + "assignments before the Exploder began its work: " + JSON.stringify(node));
+}
+
+Ep.explodeStatement = function (path, labelId) {
+  var t = util.getTypes();
+  var stmt = path.node;
+  var self = this;
+  var before, after, head;
+  t.assertStatement(stmt);
+
+  if (labelId) {
+    t.assertIdentifier(labelId);
+  } else {
+    labelId = null;
+  } // Explode BlockStatement nodes even if they do not contain a yield,
+  // because we don't want or need the curly braces.
+
+
+  if (t.isBlockStatement(stmt)) {
+    path.get("body").forEach(function (path) {
+      self.explodeStatement(path);
+    });
+    return;
+  }
+
+  if (!meta.containsLeap(stmt)) {
+    // Technically we should be able to avoid emitting the statement
+    // altogether if !meta.hasSideEffects(stmt), but that leads to
+    // confusing generated code (for instance, `while (true) {}` just
+    // disappears) and is probably a more appropriate job for a dedicated
+    // dead code elimination pass.
+    self.emit(stmt);
+    return;
+  }
+
+  switch (stmt.type) {
+    case "ExpressionStatement":
+      self.explodeExpression(path.get("expression"), true);
+      break;
+
+    case "LabeledStatement":
+      after = this.loc(); // Did you know you can break from any labeled block statement or
+      // control structure? Well, you can! Note: when a labeled loop is
+      // encountered, the leap.LabeledEntry created here will immediately
+      // enclose a leap.LoopEntry on the leap manager's stack, and both
+      // entries will have the same label. Though this works just fine, it
+      // may seem a bit redundant. In theory, we could check here to
+      // determine if stmt knows how to handle its own label; for example,
+      // stmt happens to be a WhileStatement and so we know it's going to
+      // establish its own LoopEntry when we explode it (below). Then this
+      // LabeledEntry would be unnecessary. Alternatively, we might be
+      // tempted not to pass stmt.label down into self.explodeStatement,
+      // because we've handled the label here, but that's a mistake because
+      // labeled loops may contain labeled continue statements, which is not
+      // something we can handle in this generic case. All in all, I think a
+      // little redundancy greatly simplifies the logic of this case, since
+      // it's clear that we handle all possible LabeledStatements correctly
+      // here, regardless of whether they interact with the leap manager
+      // themselves. Also remember that labels and break/continue-to-label
+      // statements are rare, and all of this logic happens at transform
+      // time, so it has no additional runtime cost.
+
+      self.leapManager.withEntry(new leap.LabeledEntry(after, stmt.label), function () {
+        self.explodeStatement(path.get("body"), stmt.label);
+      });
+      self.mark(after);
+      break;
+
+    case "WhileStatement":
+      before = this.loc();
+      after = this.loc();
+      self.mark(before);
+      self.jumpIfNot(self.explodeExpression(path.get("test")), after);
+      self.leapManager.withEntry(new leap.LoopEntry(after, before, labelId), function () {
+        self.explodeStatement(path.get("body"));
+      });
+      self.jump(before);
+      self.mark(after);
+      break;
+
+    case "DoWhileStatement":
+      var first = this.loc();
+      var test = this.loc();
+      after = this.loc();
+      self.mark(first);
+      self.leapManager.withEntry(new leap.LoopEntry(after, test, labelId), function () {
+        self.explode(path.get("body"));
+      });
+      self.mark(test);
+      self.jumpIf(self.explodeExpression(path.get("test")), first);
+      self.mark(after);
+      break;
+
+    case "ForStatement":
+      head = this.loc();
+      var update = this.loc();
+      after = this.loc();
+
+      if (stmt.init) {
+        // We pass true here to indicate that if stmt.init is an expression
+        // then we do not care about its result.
+        self.explode(path.get("init"), true);
+      }
+
+      self.mark(head);
+
+      if (stmt.test) {
+        self.jumpIfNot(self.explodeExpression(path.get("test")), after);
+      } else {// No test means continue unconditionally.
+      }
+
+      self.leapManager.withEntry(new leap.LoopEntry(after, update, labelId), function () {
+        self.explodeStatement(path.get("body"));
+      });
+      self.mark(update);
+
+      if (stmt.update) {
+        // We pass true here to indicate that if stmt.update is an
+        // expression then we do not care about its result.
+        self.explode(path.get("update"), true);
+      }
+
+      self.jump(head);
+      self.mark(after);
+      break;
+
+    case "TypeCastExpression":
+      return self.explodeExpression(path.get("expression"));
+
+    case "ForInStatement":
+      head = this.loc();
+      after = this.loc();
+      var keyIterNextFn = self.makeTempVar();
+      self.emitAssign(keyIterNextFn, t.callExpression(util.runtimeProperty("keys"), [self.explodeExpression(path.get("right"))]));
+      self.mark(head);
+      var keyInfoTmpVar = self.makeTempVar();
+      self.jumpIf(t.memberExpression(t.assignmentExpression("=", keyInfoTmpVar, t.callExpression(t.cloneDeep(keyIterNextFn), [])), t.identifier("done"), false), after);
+      self.emitAssign(stmt.left, t.memberExpression(t.cloneDeep(keyInfoTmpVar), t.identifier("value"), false));
+      self.leapManager.withEntry(new leap.LoopEntry(after, head, labelId), function () {
+        self.explodeStatement(path.get("body"));
+      });
+      self.jump(head);
+      self.mark(after);
+      break;
+
+    case "BreakStatement":
+      self.emitAbruptCompletion({
+        type: "break",
+        target: self.leapManager.getBreakLoc(stmt.label)
+      });
+      break;
+
+    case "ContinueStatement":
+      self.emitAbruptCompletion({
+        type: "continue",
+        target: self.leapManager.getContinueLoc(stmt.label)
+      });
+      break;
+
+    case "SwitchStatement":
+      // Always save the discriminant into a temporary variable in case the
+      // test expressions overwrite values like context.sent.
+      var disc = self.emitAssign(self.makeTempVar(), self.explodeExpression(path.get("discriminant")));
+      after = this.loc();
+      var defaultLoc = this.loc();
+      var condition = defaultLoc;
+      var caseLocs = []; // If there are no cases, .cases might be undefined.
+
+      var cases = stmt.cases || [];
+
+      for (var i = cases.length - 1; i >= 0; --i) {
+        var c = cases[i];
+        t.assertSwitchCase(c);
+
+        if (c.test) {
+          condition = t.conditionalExpression(t.binaryExpression("===", t.cloneDeep(disc), c.test), caseLocs[i] = this.loc(), condition);
+        } else {
+          caseLocs[i] = defaultLoc;
+        }
+      }
+
+      var discriminant = path.get("discriminant");
+      util.replaceWithOrRemove(discriminant, condition);
+      self.jump(self.explodeExpression(discriminant));
+      self.leapManager.withEntry(new leap.SwitchEntry(after), function () {
+        path.get("cases").forEach(function (casePath) {
+          var i = casePath.key;
+          self.mark(caseLocs[i]);
+          casePath.get("consequent").forEach(function (path) {
+            self.explodeStatement(path);
+          });
+        });
+      });
+      self.mark(after);
+
+      if (defaultLoc.value === -1) {
+        self.mark(defaultLoc);
+
+        _assert["default"].strictEqual(after.value, defaultLoc.value);
+      }
+
+      break;
+
+    case "IfStatement":
+      var elseLoc = stmt.alternate && this.loc();
+      after = this.loc();
+      self.jumpIfNot(self.explodeExpression(path.get("test")), elseLoc || after);
+      self.explodeStatement(path.get("consequent"));
+
+      if (elseLoc) {
+        self.jump(after);
+        self.mark(elseLoc);
+        self.explodeStatement(path.get("alternate"));
+      }
+
+      self.mark(after);
+      break;
+
+    case "ReturnStatement":
+      self.emitAbruptCompletion({
+        type: "return",
+        value: self.explodeExpression(path.get("argument"))
+      });
+      break;
+
+    case "WithStatement":
+      throw new Error("WithStatement not supported in generator functions.");
+
+    case "TryStatement":
+      after = this.loc();
+      var handler = stmt.handler;
+      var catchLoc = handler && this.loc();
+      var catchEntry = catchLoc && new leap.CatchEntry(catchLoc, handler.param);
+      var finallyLoc = stmt.finalizer && this.loc();
+      var finallyEntry = finallyLoc && new leap.FinallyEntry(finallyLoc, after);
+      var tryEntry = new leap.TryEntry(self.getUnmarkedCurrentLoc(), catchEntry, finallyEntry);
+      self.tryEntries.push(tryEntry);
+      self.updateContextPrevLoc(tryEntry.firstLoc);
+      self.leapManager.withEntry(tryEntry, function () {
+        self.explodeStatement(path.get("block"));
+
+        if (catchLoc) {
+          if (finallyLoc) {
+            // If we have both a catch block and a finally block, then
+            // because we emit the catch block first, we need to jump over
+            // it to the finally block.
+            self.jump(finallyLoc);
+          } else {
+            // If there is no finally block, then we need to jump over the
+            // catch block to the fall-through location.
+            self.jump(after);
+          }
+
+          self.updateContextPrevLoc(self.mark(catchLoc));
+          var bodyPath = path.get("handler.body");
+          var safeParam = self.makeTempVar();
+          self.clearPendingException(tryEntry.firstLoc, safeParam);
+          bodyPath.traverse(catchParamVisitor, {
+            getSafeParam: function getSafeParam() {
+              return t.cloneDeep(safeParam);
+            },
+            catchParamName: handler.param.name
+          });
+          self.leapManager.withEntry(catchEntry, function () {
+            self.explodeStatement(bodyPath);
+          });
+        }
+
+        if (finallyLoc) {
+          self.updateContextPrevLoc(self.mark(finallyLoc));
+          self.leapManager.withEntry(finallyEntry, function () {
+            self.explodeStatement(path.get("finalizer"));
+          });
+          self.emit(t.returnStatement(t.callExpression(self.contextProperty("finish"), [finallyEntry.firstLoc])));
+        }
+      });
+      self.mark(after);
+      break;
+
+    case "ThrowStatement":
+      self.emit(t.throwStatement(self.explodeExpression(path.get("argument"))));
+      break;
+
+    default:
+      throw new Error("unknown Statement of type " + JSON.stringify(stmt.type));
+  }
+};
+
+var catchParamVisitor = {
+  Identifier: function Identifier(path, state) {
+    if (path.node.name === state.catchParamName && util.isReference(path)) {
+      util.replaceWithOrRemove(path, state.getSafeParam());
+    }
+  },
+  Scope: function Scope(path, state) {
+    if (path.scope.hasOwnBinding(state.catchParamName)) {
+      // Don't descend into nested scopes that shadow the catch
+      // parameter with their own declarations.
+      path.skip();
+    }
+  }
+};
+
+Ep.emitAbruptCompletion = function (record) {
+  if (!isValidCompletion(record)) {
+    _assert["default"].ok(false, "invalid completion record: " + JSON.stringify(record));
+  }
+
+  _assert["default"].notStrictEqual(record.type, "normal", "normal completions are not abrupt");
+
+  var t = util.getTypes();
+  var abruptArgs = [t.stringLiteral(record.type)];
+
+  if (record.type === "break" || record.type === "continue") {
+    t.assertLiteral(record.target);
+    abruptArgs[1] = this.insertedLocs.has(record.target) ? record.target : t.cloneDeep(record.target);
+  } else if (record.type === "return" || record.type === "throw") {
+    if (record.value) {
+      t.assertExpression(record.value);
+      abruptArgs[1] = this.insertedLocs.has(record.value) ? record.value : t.cloneDeep(record.value);
+    }
+  }
+
+  this.emit(t.returnStatement(t.callExpression(this.contextProperty("abrupt"), abruptArgs)));
+};
+
+function isValidCompletion(record) {
+  var type = record.type;
+
+  if (type === "normal") {
+    return !hasOwn.call(record, "target");
+  }
+
+  if (type === "break" || type === "continue") {
+    return !hasOwn.call(record, "value") && util.getTypes().isLiteral(record.target);
+  }
+
+  if (type === "return" || type === "throw") {
+    return hasOwn.call(record, "value") && !hasOwn.call(record, "target");
+  }
+
+  return false;
+} // Not all offsets into emitter.listing are potential jump targets. For
+// example, execution typically falls into the beginning of a try block
+// without jumping directly there. This method returns the current offset
+// without marking it, so that a switch case will not necessarily be
+// generated for this offset (I say "not necessarily" because the same
+// location might end up being marked in the process of emitting other
+// statements). There's no logical harm in marking such locations as jump
+// targets, but minimizing the number of switch cases keeps the generated
+// code shorter.
+
+
+Ep.getUnmarkedCurrentLoc = function () {
+  return util.getTypes().numericLiteral(this.listing.length);
+}; // The context.prev property takes the value of context.next whenever we
+// evaluate the switch statement discriminant, which is generally good
+// enough for tracking the last location we jumped to, but sometimes
+// context.prev needs to be more precise, such as when we fall
+// successfully out of a try block and into a finally block without
+// jumping. This method exists to update context.prev to the freshest
+// available location. If we were implementing a full interpreter, we
+// would know the location of the current instruction with complete
+// precision at all times, but we don't have that luxury here, as it would
+// be costly and verbose to set context.prev before every statement.
+
+
+Ep.updateContextPrevLoc = function (loc) {
+  var t = util.getTypes();
+
+  if (loc) {
+    t.assertLiteral(loc);
+
+    if (loc.value === -1) {
+      // If an uninitialized location literal was passed in, set its value
+      // to the current this.listing.length.
+      loc.value = this.listing.length;
+    } else {
+      // Otherwise assert that the location matches the current offset.
+      _assert["default"].strictEqual(loc.value, this.listing.length);
+    }
+  } else {
+    loc = this.getUnmarkedCurrentLoc();
+  } // Make sure context.prev is up to date in case we fell into this try
+  // statement without jumping to it. TODO Consider avoiding this
+  // assignment when we know control must have jumped here.
+
+
+  this.emitAssign(this.contextProperty("prev"), loc);
+};
+
+Ep.explodeExpression = function (path, ignoreResult) {
+  var t = util.getTypes();
+  var expr = path.node;
+
+  if (expr) {
+    t.assertExpression(expr);
+  } else {
+    return expr;
+  }
+
+  var self = this;
+  var result; // Used optionally by several cases below.
+
+  var after;
+
+  function finish(expr) {
+    t.assertExpression(expr);
+
+    if (ignoreResult) {
+      self.emit(expr);
+    } else {
+      return expr;
+    }
+  } // If the expression does not contain a leap, then we either emit the
+  // expression as a standalone statement or return it whole.
+
+
+  if (!meta.containsLeap(expr)) {
+    return finish(expr);
+  } // If any child contains a leap (such as a yield or labeled continue or
+  // break statement), then any sibling subexpressions will almost
+  // certainly have to be exploded in order to maintain the order of their
+  // side effects relative to the leaping child(ren).
+
+
+  var hasLeapingChildren = meta.containsLeap.onlyChildren(expr); // In order to save the rest of explodeExpression from a combinatorial
+  // trainwreck of special cases, explodeViaTempVar is responsible for
+  // deciding when a subexpression needs to be "exploded," which is my
+  // very technical term for emitting the subexpression as an assignment
+  // to a temporary variable and the substituting the temporary variable
+  // for the original subexpression. Think of exploded view diagrams, not
+  // Michael Bay movies. The point of exploding subexpressions is to
+  // control the precise order in which the generated code realizes the
+  // side effects of those subexpressions.
+
+  function explodeViaTempVar(tempVar, childPath, ignoreChildResult) {
+    _assert["default"].ok(!ignoreChildResult || !tempVar, "Ignoring the result of a child expression but forcing it to " + "be assigned to a temporary variable?");
+
+    var result = self.explodeExpression(childPath, ignoreChildResult);
+
+    if (ignoreChildResult) {// Side effects already emitted above.
+    } else if (tempVar || hasLeapingChildren && !t.isLiteral(result)) {
+      // If tempVar was provided, then the result will always be assigned
+      // to it, even if the result does not otherwise need to be assigned
+      // to a temporary variable.  When no tempVar is provided, we have
+      // the flexibility to decide whether a temporary variable is really
+      // necessary.  Unfortunately, in general, a temporary variable is
+      // required whenever any child contains a yield expression, since it
+      // is difficult to prove (at all, let alone efficiently) whether
+      // this result would evaluate to the same value before and after the
+      // yield (see #206).  One narrow case where we can prove it doesn't
+      // matter (and thus we do not need a temporary variable) is when the
+      // result in question is a Literal value.
+      result = self.emitAssign(tempVar || self.makeTempVar(), result);
+    }
+
+    return result;
+  } // If ignoreResult is true, then we must take full responsibility for
+  // emitting the expression with all its side effects, and we should not
+  // return a result.
+
+
+  switch (expr.type) {
+    case "MemberExpression":
+      return finish(t.memberExpression(self.explodeExpression(path.get("object")), expr.computed ? explodeViaTempVar(null, path.get("property")) : expr.property, expr.computed));
+
+    case "CallExpression":
+      var calleePath = path.get("callee");
+      var argsPath = path.get("arguments");
+      var newCallee;
+      var newArgs;
+      var hasLeapingArgs = argsPath.some(function (argPath) {
+        return meta.containsLeap(argPath.node);
+      });
+      var injectFirstArg = null;
+
+      if (t.isMemberExpression(calleePath.node)) {
+        if (hasLeapingArgs) {
+          // If the arguments of the CallExpression contained any yield
+          // expressions, then we need to be sure to evaluate the callee
+          // before evaluating the arguments, but if the callee was a member
+          // expression, then we must be careful that the object of the
+          // member expression still gets bound to `this` for the call.
+          var newObject = explodeViaTempVar( // Assign the exploded callee.object expression to a temporary
+          // variable so that we can use it twice without reevaluating it.
+          self.makeTempVar(), calleePath.get("object"));
+          var newProperty = calleePath.node.computed ? explodeViaTempVar(null, calleePath.get("property")) : calleePath.node.property;
+          injectFirstArg = newObject;
+          newCallee = t.memberExpression(t.memberExpression(t.cloneDeep(newObject), newProperty, calleePath.node.computed), t.identifier("call"), false);
+        } else {
+          newCallee = self.explodeExpression(calleePath);
+        }
+      } else {
+        newCallee = explodeViaTempVar(null, calleePath);
+
+        if (t.isMemberExpression(newCallee)) {
+          // If the callee was not previously a MemberExpression, then the
+          // CallExpression was "unqualified," meaning its `this` object
+          // should be the global object. If the exploded expression has
+          // become a MemberExpression (e.g. a context property, probably a
+          // temporary variable), then we need to force it to be unqualified
+          // by using the (0, object.property)(...) trick; otherwise, it
+          // will receive the object of the MemberExpression as its `this`
+          // object.
+          newCallee = t.sequenceExpression([t.numericLiteral(0), t.cloneDeep(newCallee)]);
+        }
+      }
+
+      if (hasLeapingArgs) {
+        newArgs = argsPath.map(function (argPath) {
+          return explodeViaTempVar(null, argPath);
+        });
+        if (injectFirstArg) newArgs.unshift(injectFirstArg);
+        newArgs = newArgs.map(function (arg) {
+          return t.cloneDeep(arg);
+        });
+      } else {
+        newArgs = path.node.arguments;
+      }
+
+      return finish(t.callExpression(newCallee, newArgs));
+
+    case "NewExpression":
+      return finish(t.newExpression(explodeViaTempVar(null, path.get("callee")), path.get("arguments").map(function (argPath) {
+        return explodeViaTempVar(null, argPath);
+      })));
+
+    case "ObjectExpression":
+      return finish(t.objectExpression(path.get("properties").map(function (propPath) {
+        if (propPath.isObjectProperty()) {
+          return t.objectProperty(propPath.node.key, explodeViaTempVar(null, propPath.get("value")), propPath.node.computed);
+        } else {
+          return propPath.node;
+        }
+      })));
+
+    case "ArrayExpression":
+      return finish(t.arrayExpression(path.get("elements").map(function (elemPath) {
+        if (elemPath.isSpreadElement()) {
+          return t.spreadElement(explodeViaTempVar(null, elemPath.get("argument")));
+        } else {
+          return explodeViaTempVar(null, elemPath);
+        }
+      })));
+
+    case "SequenceExpression":
+      var lastIndex = expr.expressions.length - 1;
+      path.get("expressions").forEach(function (exprPath) {
+        if (exprPath.key === lastIndex) {
+          result = self.explodeExpression(exprPath, ignoreResult);
+        } else {
+          self.explodeExpression(exprPath, true);
+        }
+      });
+      return result;
+
+    case "LogicalExpression":
+      after = this.loc();
+
+      if (!ignoreResult) {
+        result = self.makeTempVar();
+      }
+
+      var left = explodeViaTempVar(result, path.get("left"));
+
+      if (expr.operator === "&&") {
+        self.jumpIfNot(left, after);
+      } else {
+        _assert["default"].strictEqual(expr.operator, "||");
+
+        self.jumpIf(left, after);
+      }
+
+      explodeViaTempVar(result, path.get("right"), ignoreResult);
+      self.mark(after);
+      return result;
+
+    case "ConditionalExpression":
+      var elseLoc = this.loc();
+      after = this.loc();
+      var test = self.explodeExpression(path.get("test"));
+      self.jumpIfNot(test, elseLoc);
+
+      if (!ignoreResult) {
+        result = self.makeTempVar();
+      }
+
+      explodeViaTempVar(result, path.get("consequent"), ignoreResult);
+      self.jump(after);
+      self.mark(elseLoc);
+      explodeViaTempVar(result, path.get("alternate"), ignoreResult);
+      self.mark(after);
+      return result;
+
+    case "UnaryExpression":
+      return finish(t.unaryExpression(expr.operator, // Can't (and don't need to) break up the syntax of the argument.
+      // Think about delete a[b].
+      self.explodeExpression(path.get("argument")), !!expr.prefix));
+
+    case "BinaryExpression":
+      return finish(t.binaryExpression(expr.operator, explodeViaTempVar(null, path.get("left")), explodeViaTempVar(null, path.get("right"))));
+
+    case "AssignmentExpression":
+      if (expr.operator === "=") {
+        // If this is a simple assignment, the left hand side does not need
+        // to be read before the right hand side is evaluated, so we can
+        // avoid the more complicated logic below.
+        return finish(t.assignmentExpression(expr.operator, self.explodeExpression(path.get("left")), self.explodeExpression(path.get("right"))));
+      }
+
+      var lhs = self.explodeExpression(path.get("left"));
+      var temp = self.emitAssign(self.makeTempVar(), lhs); // For example,
+      //
+      //   x += yield y
+      //
+      // becomes
+      //
+      //   context.t0 = x
+      //   x = context.t0 += yield y
+      //
+      // so that the left-hand side expression is read before the yield.
+      // Fixes https://github.com/facebook/regenerator/issues/345.
+
+      return finish(t.assignmentExpression("=", t.cloneDeep(lhs), t.assignmentExpression(expr.operator, t.cloneDeep(temp), self.explodeExpression(path.get("right")))));
+
+    case "UpdateExpression":
+      return finish(t.updateExpression(expr.operator, self.explodeExpression(path.get("argument")), expr.prefix));
+
+    case "YieldExpression":
+      after = this.loc();
+      var arg = expr.argument && self.explodeExpression(path.get("argument"));
+
+      if (arg && expr.delegate) {
+        var _result = self.makeTempVar();
+
+        var _ret = t.returnStatement(t.callExpression(self.contextProperty("delegateYield"), [arg, t.stringLiteral(_result.property.name), after]));
+
+        _ret.loc = expr.loc;
+        self.emit(_ret);
+        self.mark(after);
+        return _result;
+      }
+
+      self.emitAssign(self.contextProperty("next"), after);
+      var ret = t.returnStatement(t.cloneDeep(arg) || null); // Preserve the `yield` location so that source mappings for the statements
+      // link back to the yield properly.
+
+      ret.loc = expr.loc;
+      self.emit(ret);
+      self.mark(after);
+      return self.contextProperty("sent");
+
+    default:
+      throw new Error("unknown Expression of type " + JSON.stringify(expr.type));
+  }
+};

web/node_modules/regenerator-transform/lib/hoist.js

@@ -0,0 +1,136 @@
+"use strict";
+
+var _interopRequireWildcard = require("@babel/runtime/helpers/interopRequireWildcard");
+
+var util = _interopRequireWildcard(require("./util"));
+
+/**
+ * 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);
+};

web/node_modules/regenerator-transform/lib/index.js

@@ -0,0 +1,29 @@
+"use strict";
+
+exports.__esModule = true;
+exports["default"] = _default;
+
+var _visit = require("./visit");
+
+/**
+ * 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.
+ */
+function _default(context) {
+  var plugin = {
+    visitor: (0, _visit.getVisitor)(context)
+  }; // Some presets manually call child presets, but fail to pass along the
+  // context object. Out of an abundance of caution, we verify that it
+  // exists first to avoid causing unnecessary breaking changes.
+
+  var version = context && context.version; // The "name" property is not allowed in older versions of Babel (6.x)
+  // and will cause the plugin validator to throw an exception.
+
+  if (version && parseInt(version, 10) >= 7) {
+    plugin.name = "regenerator-transform";
+  }
+
+  return plugin;
+}

web/node_modules/regenerator-transform/lib/leap.js

@@ -0,0 +1,178 @@
+"use strict";
+
+var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
+
+var _assert = _interopRequireDefault(require("assert"));
+
+var _emit = require("./emit");
+
+var _util = require("util");
+
+var _util2 = require("./util");
+
+/**
+ * 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.
+ */
+function Entry() {
+  _assert["default"].ok(this instanceof Entry);
+}
+
+function FunctionEntry(returnLoc) {
+  Entry.call(this);
+  (0, _util2.getTypes)().assertLiteral(returnLoc);
+  this.returnLoc = returnLoc;
+}
+
+(0, _util.inherits)(FunctionEntry, Entry);
+exports.FunctionEntry = FunctionEntry;
+
+function LoopEntry(breakLoc, continueLoc, label) {
+  Entry.call(this);
+  var t = (0, _util2.getTypes)();
+  t.assertLiteral(breakLoc);
+  t.assertLiteral(continueLoc);
+
+  if (label) {
+    t.assertIdentifier(label);
+  } else {
+    label = null;
+  }
+
+  this.breakLoc = breakLoc;
+  this.continueLoc = continueLoc;
+  this.label = label;
+}
+
+(0, _util.inherits)(LoopEntry, Entry);
+exports.LoopEntry = LoopEntry;
+
+function SwitchEntry(breakLoc) {
+  Entry.call(this);
+  (0, _util2.getTypes)().assertLiteral(breakLoc);
+  this.breakLoc = breakLoc;
+}
+
+(0, _util.inherits)(SwitchEntry, Entry);
+exports.SwitchEntry = SwitchEntry;
+
+function TryEntry(firstLoc, catchEntry, finallyEntry) {
+  Entry.call(this);
+  var t = (0, _util2.getTypes)();
+  t.assertLiteral(firstLoc);
+
+  if (catchEntry) {
+    _assert["default"].ok(catchEntry instanceof CatchEntry);
+  } else {
+    catchEntry = null;
+  }
+
+  if (finallyEntry) {
+    _assert["default"].ok(finallyEntry instanceof FinallyEntry);
+  } else {
+    finallyEntry = null;
+  } // Have to have one or the other (or both).
+
+
+  _assert["default"].ok(catchEntry || finallyEntry);
+
+  this.firstLoc = firstLoc;
+  this.catchEntry = catchEntry;
+  this.finallyEntry = finallyEntry;
+}
+
+(0, _util.inherits)(TryEntry, Entry);
+exports.TryEntry = TryEntry;
+
+function CatchEntry(firstLoc, paramId) {
+  Entry.call(this);
+  var t = (0, _util2.getTypes)();
+  t.assertLiteral(firstLoc);
+  t.assertIdentifier(paramId);
+  this.firstLoc = firstLoc;
+  this.paramId = paramId;
+}
+
+(0, _util.inherits)(CatchEntry, Entry);
+exports.CatchEntry = CatchEntry;
+
+function FinallyEntry(firstLoc, afterLoc) {
+  Entry.call(this);
+  var t = (0, _util2.getTypes)();
+  t.assertLiteral(firstLoc);
+  t.assertLiteral(afterLoc);
+  this.firstLoc = firstLoc;
+  this.afterLoc = afterLoc;
+}
+
+(0, _util.inherits)(FinallyEntry, Entry);
+exports.FinallyEntry = FinallyEntry;
+
+function LabeledEntry(breakLoc, label) {
+  Entry.call(this);
+  var t = (0, _util2.getTypes)();
+  t.assertLiteral(breakLoc);
+  t.assertIdentifier(label);
+  this.breakLoc = breakLoc;
+  this.label = label;
+}
+
+(0, _util.inherits)(LabeledEntry, Entry);
+exports.LabeledEntry = LabeledEntry;
+
+function LeapManager(emitter) {
+  _assert["default"].ok(this instanceof LeapManager);
+
+  _assert["default"].ok(emitter instanceof _emit.Emitter);
+
+  this.emitter = emitter;
+  this.entryStack = [new FunctionEntry(emitter.finalLoc)];
+}
+
+var LMp = LeapManager.prototype;
+exports.LeapManager = LeapManager;
+
+LMp.withEntry = function (entry, callback) {
+  _assert["default"].ok(entry instanceof Entry);
+
+  this.entryStack.push(entry);
+
+  try {
+    callback.call(this.emitter);
+  } finally {
+    var popped = this.entryStack.pop();
+
+    _assert["default"].strictEqual(popped, entry);
+  }
+};
+
+LMp._findLeapLocation = function (property, label) {
+  for (var i = this.entryStack.length - 1; i >= 0; --i) {
+    var entry = this.entryStack[i];
+    var loc = entry[property];
+
+    if (loc) {
+      if (label) {
+        if (entry.label && entry.label.name === label.name) {
+          return loc;
+        }
+      } else if (entry instanceof LabeledEntry) {// Ignore LabeledEntry entries unless we are actually breaking to
+        // a label.
+      } else {
+        return loc;
+      }
+    }
+  }
+
+  return null;
+};
+
+LMp.getBreakLoc = function (label) {
+  return this._findLeapLocation("breakLoc", label);
+};
+
+LMp.getContinueLoc = function (label) {
+  return this._findLeapLocation("continueLoc", label);
+};

web/node_modules/regenerator-transform/lib/meta.js

@@ -0,0 +1,113 @@
+"use strict";
+
+var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
+
+var _assert = _interopRequireDefault(require("assert"));
+
+var _util = require("./util.js");
+
+/**
+ * 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 mMap = new WeakMap();
+
+function m(node) {
+  if (!mMap.has(node)) {
+    mMap.set(node, {});
+  }
+
+  return mMap.get(node);
+}
+
+var hasOwn = Object.prototype.hasOwnProperty;
+
+function makePredicate(propertyName, knownTypes) {
+  function onlyChildren(node) {
+    var t = (0, _util.getTypes)();
+    t.assertNode(node); // Assume no side effects until we find out otherwise.
+
+    var result = false;
+
+    function check(child) {
+      if (result) {// Do nothing.
+      } else if (Array.isArray(child)) {
+        child.some(check);
+      } else if (t.isNode(child)) {
+        _assert["default"].strictEqual(result, false);
+
+        result = predicate(child);
+      }
+
+      return result;
+    }
+
+    var keys = t.VISITOR_KEYS[node.type];
+
+    if (keys) {
+      for (var i = 0; i < keys.length; i++) {
+        var key = keys[i];
+        var child = node[key];
+        check(child);
+      }
+    }
+
+    return result;
+  }
+
+  function predicate(node) {
+    (0, _util.getTypes)().assertNode(node);
+    var meta = m(node);
+    if (hasOwn.call(meta, propertyName)) return meta[propertyName]; // Certain types are "opaque," which means they have no side
+    // effects or leaps and we don't care about their subexpressions.
+
+    if (hasOwn.call(opaqueTypes, node.type)) return meta[propertyName] = false;
+    if (hasOwn.call(knownTypes, node.type)) return meta[propertyName] = true;
+    return meta[propertyName] = onlyChildren(node);
+  }
+
+  predicate.onlyChildren = onlyChildren;
+  return predicate;
+}
+
+var opaqueTypes = {
+  FunctionExpression: true,
+  ArrowFunctionExpression: true
+}; // These types potentially have side effects regardless of what side
+// effects their subexpressions have.
+
+var sideEffectTypes = {
+  CallExpression: true,
+  // Anything could happen!
+  ForInStatement: true,
+  // Modifies the key variable.
+  UnaryExpression: true,
+  // Think delete.
+  BinaryExpression: true,
+  // Might invoke .toString() or .valueOf().
+  AssignmentExpression: true,
+  // Side-effecting by definition.
+  UpdateExpression: true,
+  // Updates are essentially assignments.
+  NewExpression: true // Similar to CallExpression.
+
+}; // These types are the direct cause of all leaps in control flow.
+
+var leapTypes = {
+  YieldExpression: true,
+  BreakStatement: true,
+  ContinueStatement: true,
+  ReturnStatement: true,
+  ThrowStatement: true
+}; // All leap types are also side effect types.
+
+for (var type in leapTypes) {
+  if (hasOwn.call(leapTypes, type)) {
+    sideEffectTypes[type] = leapTypes[type];
+  }
+}
+
+exports.hasSideEffects = makePredicate("hasSideEffects", sideEffectTypes);
+exports.containsLeap = makePredicate("containsLeap", leapTypes);

web/node_modules/regenerator-transform/lib/replaceShorthandObjectMethod.js

@@ -0,0 +1,79 @@
+"use strict";
+
+var _interopRequireWildcard = require("@babel/runtime/helpers/interopRequireWildcard");
+
+exports.__esModule = true;
+exports["default"] = replaceShorthandObjectMethod;
+
+var util = _interopRequireWildcard(require("./util"));
+
+/**
+ * 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.
+ */
+// this function converts a shorthand object generator method into a normal
+// (non-shorthand) object property which is a generator function expression. for
+// example, this:
+//
+//  var foo = {
+//    *bar(baz) { return 5; }
+//  }
+//
+// should be replaced with:
+//
+//  var foo = {
+//    bar: function*(baz) { return 5; }
+//  }
+//
+// to do this, it clones the parameter array and the body of the object generator
+// method into a new FunctionExpression.
+//
+// this method can be passed any Function AST node path, and it will return
+// either:
+//   a) the path that was passed in (iff the path did not need to be replaced) or
+//   b) the path of the new FunctionExpression that was created as a replacement
+//     (iff the path did need to be replaced)
+//
+// In either case, though, the caller can count on the fact that the return value
+// is a Function AST node path.
+//
+// If this function is called with an AST node path that is not a Function (or with an
+// argument that isn't an AST node path), it will throw an error.
+function replaceShorthandObjectMethod(path) {
+  var t = util.getTypes();
+
+  if (!path.node || !t.isFunction(path.node)) {
+    throw new Error("replaceShorthandObjectMethod can only be called on Function AST node paths.");
+  } // this function only replaces shorthand object methods (called ObjectMethod
+  // in Babel-speak).
+
+
+  if (!t.isObjectMethod(path.node)) {
+    return path;
+  } // this function only replaces generators.
+
+
+  if (!path.node.generator) {
+    return path;
+  }
+
+  var parameters = path.node.params.map(function (param) {
+    return t.cloneDeep(param);
+  });
+  var functionExpression = t.functionExpression(null, // id
+  parameters, // params
+  t.cloneDeep(path.node.body), // body
+  path.node.generator, path.node.async);
+  util.replaceWithOrRemove(path, t.objectProperty(t.cloneDeep(path.node.key), // key
+  functionExpression, //value
+  path.node.computed, // computed
+  false // shorthand
+  )); // path now refers to the ObjectProperty AST node path, but we want to return a
+  // Function AST node path for the function expression we created. we know that
+  // the FunctionExpression we just created is the value of the ObjectProperty,
+  // so return the "value" path off of this path.
+
+  return path.get("value");
+}

web/node_modules/regenerator-transform/lib/util.js

@@ -0,0 +1,56 @@
+"use strict";
+
+exports.__esModule = true;
+exports.wrapWithTypes = wrapWithTypes;
+exports.getTypes = getTypes;
+exports.runtimeProperty = runtimeProperty;
+exports.isReference = isReference;
+exports.replaceWithOrRemove = replaceWithOrRemove;
+
+/**
+ * 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 currentTypes = null;
+
+function wrapWithTypes(types, fn) {
+  return function () {
+    var oldTypes = currentTypes;
+    currentTypes = types;
+
+    try {
+      for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
+        args[_key] = arguments[_key];
+      }
+
+      return fn.apply(this, args);
+    } finally {
+      currentTypes = oldTypes;
+    }
+  };
+}
+
+function getTypes() {
+  return currentTypes;
+}
+
+function runtimeProperty(name) {
+  var t = getTypes();
+  return t.memberExpression(t.identifier("regeneratorRuntime"), t.identifier(name), false);
+}
+
+function isReference(path) {
+  return path.isReferenced() || path.parentPath.isAssignmentExpression({
+    left: path.node
+  });
+}
+
+function replaceWithOrRemove(path, replacement) {
+  if (replacement) {
+    path.replaceWith(replacement);
+  } else {
+    path.remove();
+  }
+}

web/node_modules/regenerator-transform/lib/visit.js

@@ -0,0 +1,326 @@
+/**
+ * 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"));
+
+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 markInfo = new WeakMap();
+
+function getMarkInfo(node) {
+  if (!markInfo.has(node)) {
+    markInfo.set(node, {});
+  }
+
+  return markInfo.get(node);
+}
+
+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));
+  }
+};