summaryrefslogtreecommitdiff
path: root/node_modules/regenerator-transform/src/meta.js
diff options
context:
space:
mode:
Diffstat (limited to 'node_modules/regenerator-transform/src/meta.js')
-rw-r--r--node_modules/regenerator-transform/src/meta.js110
1 files changed, 0 insertions, 110 deletions
diff --git a/node_modules/regenerator-transform/src/meta.js b/node_modules/regenerator-transform/src/meta.js
deleted file mode 100644
index dea4c6be..00000000
--- a/node_modules/regenerator-transform/src/meta.js
+++ /dev/null
@@ -1,110 +0,0 @@
-/**
- * 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.
- */
-
-import assert from "assert";
-import { getTypes } from "./util.js";
-
-const mMap = new WeakMap();
-function m(node) {
- if (!mMap.has(node)) {
- mMap.set(node, {});
- }
- return mMap.get(node);
-}
-
-const hasOwn = Object.prototype.hasOwnProperty;
-
-function makePredicate(propertyName, knownTypes) {
- function onlyChildren(node) {
- const t = getTypes();
- t.assertNode(node);
-
- // Assume no side effects until we find out otherwise.
- let result = false;
-
- function check(child) {
- if (result) {
- // Do nothing.
- } else if (Array.isArray(child)) {
- child.some(check);
- } else if (t.isNode(child)) {
- assert.strictEqual(result, false);
- result = predicate(child);
- }
- return result;
- }
-
- let keys = t.VISITOR_KEYS[node.type];
- if (keys) {
- for (let i = 0; i < keys.length; i++) {
- let key = keys[i];
- let child = node[key];
- check(child);
- }
- }
-
- return result;
- }
-
- function predicate(node) {
- getTypes().assertNode(node);
-
- let 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;
-}
-
-let opaqueTypes = {
- FunctionExpression: true,
- ArrowFunctionExpression: true
-};
-
-// These types potentially have side effects regardless of what side
-// effects their subexpressions have.
-let 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.
-let leapTypes = {
- YieldExpression: true,
- BreakStatement: true,
- ContinueStatement: true,
- ReturnStatement: true,
- ThrowStatement: true
-};
-
-// All leap types are also side effect types.
-for (let type in leapTypes) {
- if (hasOwn.call(leapTypes, type)) {
- sideEffectTypes[type] = leapTypes[type];
- }
-}
-
-exports.hasSideEffects = makePredicate("hasSideEffects", sideEffectTypes);
-exports.containsLeap = makePredicate("containsLeap", leapTypes);