fix(schemaproxy.js): reuse previously proxied subschemas to fix max c…

…all stack size exceeded error

Solution proposed by @bmaranville in
#252 (comment). Updated to work with
7.1.1.

fix #252

lib/schemaProxy.js

@@ -34,7 +34,7 @@ function loadExamples(file, num = 1) {
 }
 
 const handler = ({
- root = '', fullpath = null, filename = '.', schemas, parent = null, slugger,
+ root = '', fullpath = null, filename = '.', schemas, subschemas, parent = null, slugger,
 }) => {
  const meta = {};
 
@@ -162,14 +162,23 @@ const handler = ({
  }
 
  // console.log('making new proxy from', target, prop, 'receiver', receiver[symbols.id]);
- const subschema = new Proxy(retval, handler({
- root: `${root}/${prop}`,
- parent: receiver,
- fullpath,
- filename,
- schemas,
- slugger,
- }));
+ let subschema;
+ if (subschemas.has(retval)) {
+ subschema = subschemas.get(retval);
+ }
+ else {
+ subschema = new Proxy(retval, handler({
+ root: `${root}/${prop}`,
+ parent: receiver,
+ fullpath,
+ filename,
+ schemas,
+ subschemas,
+ slugger,
+ }));
+
+ subschemas.set(retval, subschema);
+ }
 
  if (subschema[keyword`$id`]) {
  // stow away the schema for lookup
@@ -190,14 +199,16 @@ export default function loader() {
  files: {},
  };
 
+ const subschemas = new Map();
+
  const slugger = new GhSlugger();
 
  return (/** @type {string} */ name, /** @type {any} */ schema) => {
  // console.log('loading', name);
  const filename = path.basename(name);
  const fullpath = name === filename ? undefined : name;
  const proxied = new Proxy(schema, handler({
- filename, fullpath, schemas, slugger,
+ filename, fullpath, schemas, subschemas, slugger,
  }));
  schemas.loaded.push(proxied);
  if (proxied[keyword`$id`]) {