Index: frontend/node_modules/estree-walker/src/estree-walker.js
===================================================================
--- frontend/node_modules/estree-walker/src/estree-walker.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
+++ frontend/node_modules/estree-walker/src/estree-walker.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
@@ -0,0 +1,125 @@
+function walk(ast, { enter, leave }) {
+	return visit(ast, null, enter, leave);
+}
+
+let should_skip = false;
+let should_remove = false;
+let replacement = null;
+const context = {
+	skip: () => should_skip = true,
+	remove: () => should_remove = true,
+	replace: (node) => replacement = node
+};
+
+function replace(parent, prop, index, node) {
+	if (parent) {
+		if (index !== null) {
+			parent[prop][index] = node;
+		} else {
+			parent[prop] = node;
+		}
+	}
+}
+
+function remove(parent, prop, index) {
+	if (parent) {
+		if (index !== null) {
+			parent[prop].splice(index, 1);
+		} else {
+			delete parent[prop];
+		}
+	}
+}
+
+function visit(
+	node,
+	parent,
+	enter,
+	leave,
+	prop,
+	index
+) {
+	if (node) {
+		if (enter) {
+			const _should_skip = should_skip;
+			const _should_remove = should_remove;
+			const _replacement = replacement;
+			should_skip = false;
+			should_remove = false;
+			replacement = null;
+
+			enter.call(context, node, parent, prop, index);
+
+			if (replacement) {
+				node = replacement;
+				replace(parent, prop, index, node);
+			}
+
+			if (should_remove) {
+				remove(parent, prop, index);
+			}
+
+			const skipped = should_skip;
+			const removed = should_remove;
+
+			should_skip = _should_skip;
+			should_remove = _should_remove;
+			replacement = _replacement;
+
+			if (skipped) return node;
+			if (removed) return null;
+		}
+
+		for (const key in node) {
+			const value = (node )[key];
+
+			if (typeof value !== 'object') {
+				continue;
+			}
+
+			else if (Array.isArray(value)) {
+				for (let j = 0, k = 0; j < value.length; j += 1, k += 1) {
+					if (value[j] !== null && typeof value[j].type === 'string') {
+						if (!visit(value[j], node, enter, leave, key, k)) {
+							// removed
+							j--;
+						}
+					}
+				}
+			}
+
+			else if (value !== null && typeof value.type === 'string') {
+				visit(value, node, enter, leave, key, null);
+			}
+		}
+
+		if (leave) {
+			const _replacement = replacement;
+			const _should_remove = should_remove;
+			replacement = null;
+			should_remove = false;
+
+			leave.call(context, node, parent, prop, index);
+
+			if (replacement) {
+				node = replacement;
+				replace(parent, prop, index, node);
+			}
+
+			if (should_remove) {
+				remove(parent, prop, index);
+			}
+
+			const removed = should_remove;
+
+			replacement = _replacement;
+			should_remove = _should_remove;
+
+			if (removed) return null;
+		}
+	}
+
+	return node;
+}
+
+export { walk };
Index: frontend/node_modules/estree-walker/src/index.ts
===================================================================
--- frontend/node_modules/estree-walker/src/index.ts	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
+++ frontend/node_modules/estree-walker/src/index.ts	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
@@ -0,0 +1,144 @@
+import { BaseNode } from "estree";
+
+type WalkerContext = {
+	skip: () => void;
+	remove: () => void;
+	replace: (node: BaseNode) => void;
+};
+
+type WalkerHandler = (
+	this: WalkerContext,
+	node: BaseNode,
+	parent: BaseNode,
+	key: string,
+	index: number
+) => void
+
+type Walker = {
+	enter?: WalkerHandler;
+	leave?: WalkerHandler;
+}
+
+export function walk(ast: BaseNode, { enter, leave }: Walker) {
+	return visit(ast, null, enter, leave);
+}
+
+let should_skip = false;
+let should_remove = false;
+let replacement: BaseNode = null;
+const context: WalkerContext = {
+	skip: () => should_skip = true,
+	remove: () => should_remove = true,
+	replace: (node: BaseNode) => replacement = node
+};
+
+function replace(parent: any, prop: string, index: number, node: BaseNode) {
+	if (parent) {
+		if (index !== null) {
+			parent[prop][index] = node;
+		} else {
+			parent[prop] = node;
+		}
+	}
+}
+
+function remove(parent: any, prop: string, index: number) {
+	if (parent) {
+		if (index !== null) {
+			parent[prop].splice(index, 1);
+		} else {
+			delete parent[prop];
+		}
+	}
+}
+
+function visit(
+	node: BaseNode,
+	parent: BaseNode,
+	enter: WalkerHandler,
+	leave: WalkerHandler,
+	prop?: string,
+	index?: number
+) {
+	if (node) {
+		if (enter) {
+			const _should_skip = should_skip;
+			const _should_remove = should_remove;
+			const _replacement = replacement;
+			should_skip = false;
+			should_remove = false;
+			replacement = null;
+
+			enter.call(context, node, parent, prop, index);
+
+			if (replacement) {
+				node = replacement;
+				replace(parent, prop, index, node);
+			}
+
+			if (should_remove) {
+				remove(parent, prop, index);
+			}
+
+			const skipped = should_skip;
+			const removed = should_remove;
+
+			should_skip = _should_skip;
+			should_remove = _should_remove;
+			replacement = _replacement;
+
+			if (skipped) return node;
+			if (removed) return null;
+		}
+
+		for (const key in node) {
+			const value = (node as any)[key];
+
+			if (typeof value !== 'object') {
+				continue;
+			}
+
+			else if (Array.isArray(value)) {
+				for (let j = 0, k = 0; j < value.length; j += 1, k += 1) {
+					if (value[j] !== null && typeof value[j].type === 'string') {
+						if (!visit(value[j], node, enter, leave, key, k)) {
+							// removed
+							j--;
+						}
+					}
+				}
+			}
+
+			else if (value !== null && typeof value.type === 'string') {
+				visit(value, node, enter, leave, key, null);
+			}
+		}
+
+		if (leave) {
+			const _replacement = replacement;
+			const _should_remove = should_remove;
+			replacement = null;
+			should_remove = false;
+
+			leave.call(context, node, parent, prop, index);
+
+			if (replacement) {
+				node = replacement;
+				replace(parent, prop, index, node);
+			}
+
+			if (should_remove) {
+				remove(parent, prop, index);
+			}
+
+			const removed = should_remove;
+
+			replacement = _replacement;
+			should_remove = _should_remove;
+
+			if (removed) return null;
+		}
+	}
+
+	return node;
+}