test: add recursive property accessor test

Author: LiviaMedeiros

test/parallel/test-module-property-accessors.mjs

@@ -0,0 +1,94 @@
+// Flags: --no-warnings
+import '../common/index.mjs';
+import { builtinModules } from 'node:module';
+
+// This test recursively checks all properties on builtin modules and ensures that accessing them
+// does not throw. The only valid reason for property accessor to throw is "invalid this" error
+// when property must be not accessible directly on the prototype.
+
+// Normally we don't have properties nested too deep
+const MAX_NESTING_DEPTH = 16;
+
+// Some properties can be present or absent depending on the environment
+const knownExceptions = {
+  module: [
+    // The _cache and _pathCache are populated with local paths
+    // Also, trying to access _cache.<common/index.js>.exports.then would throw
+    /^\{module\}(?:\.Module|\.default|)\.(?:_cache|_pathCache)\./,
+  ],
+};
+
+function isValid({ key, moduleName, path, propName, value, obj, fullPath }) {
+  if (knownExceptions[moduleName])
+    for (const skipRegex of knownExceptions[moduleName])
+      if (skipRegex.test(fullPath))
+        return false;
+
+  return true;
+}
+
+async function buildList(obj, moduleName, path = [], visited = new WeakMap()) {
+  if (!obj || (typeof obj !== 'object' && typeof obj !== 'function')) return [];
+
+  if (path.length > MAX_NESTING_DEPTH) {
+    throw new Error(`Too deeply nested property in ${moduleName}: ${path.join('.')}`);
+  }
+
+  // Exclude circular references
+  // Don't use plain Set, because same object can be exposed under different paths
+  if (visited.has(obj)) {
+    const visitedPaths = visited.get(obj);
+    if (visitedPaths.some((prev) => prev.length <= path.length && prev.every((seg, i) => seg === path[i]))) {
+      return [];
+    }
+    visitedPaths.push(path);
+  } else {
+    visited.set(obj, [path]);
+  }
+
+  const paths = [];
+  const deeperCalls = [];
+
+  for (const key of Reflect.ownKeys(obj)) {
+    const propName = typeof key === 'symbol' ? `[${key.description}]` : key;
+    const fullPath = `{${moduleName}}.${path.join('.')}${path.length ? '.' : ''}${propName}`;
+
+    if (!isValid({ key, moduleName, path, propName, obj, fullPath })) {
+      continue;
+    }
+
+    let value;
+    try {
+      value = await obj[key];
+    } catch (cause) {
+      // Accessing some properties directly on the prototype may throw or reject
+      // Throw informative errors if access failed anywhere/anyhow else
+      if (cause.name !== 'TypeError') {
+        throw new Error(`Access to ${fullPath} failed with name=${cause.name}`, { cause });
+      }
+      if (cause.code !== 'ERR_INVALID_THIS' && cause.code !== undefined) {
+        throw new Error(`Access to ${fullPath} failed with code=${cause.code}`, { cause });
+      }
+      if (path.at(-1) !== 'prototype') {
+        throw new Error(`Access to ${fullPath} failed but it's not on prototype`, { cause });
+      }
+    }
+    paths.push(fullPath);
+
+    if ((typeof value === 'object' || typeof value === 'function') && value !== obj) {
+      deeperCalls.push(buildList(value, moduleName, [...path, propName], visited));
+    }
+  }
+
+  return [...paths, ...(await Promise.all(deeperCalls)).flat()];
+}
+
+let total = 0;
+
+await Promise.all(builtinModules.map(async (moduleName) => {
+  const module = await import(moduleName);
+  const { length } = await buildList(module, moduleName);
+  total += length;
+}));
+
+console.log(`Checked ${total} properties across ${builtinModules.length} modules.`);