1 files changed, 124 insertions, 0 deletions
diff --git a/vanilla/node_modules/undici/lib/util/runtime-features.js b/vanilla/node_modules/undici/lib/util/runtime-features.js
new file mode 100644
index 0000000..3e62dc0
--- /dev/null
+++ b/vanilla/node_modules/undici/lib/util/runtime-features.js
@@ -0,0 +1,124 @@
+'use strict'
+
+/** @typedef {`node:${string}`} NodeModuleName */
+
+/** @type {Record<NodeModuleName, () => any>} */
+const lazyLoaders = {
+  __proto__: null,
+  'node:crypto': () => require('node:crypto'),
+  'node:sqlite': () => require('node:sqlite'),
+  'node:worker_threads': () => require('node:worker_threads'),
+  'node:zlib': () => require('node:zlib')
+}
+
+/**
+ * @param {NodeModuleName} moduleName
+ * @returns {boolean}
+ */
+function detectRuntimeFeatureByNodeModule (moduleName) {
+  try {
+    lazyLoaders[moduleName]()
+    return true
+  } catch (err) {
+    if (err.code !== 'ERR_UNKNOWN_BUILTIN_MODULE' && err.code !== 'ERR_NO_CRYPTO') {
+      throw err
+    }
+    return false
+  }
+}
+
+/**
+ * @param {NodeModuleName} moduleName
+ * @param {string} property
+ * @returns {boolean}
+ */
+function detectRuntimeFeatureByExportedProperty (moduleName, property) {
+  const module = lazyLoaders[moduleName]()
+  return typeof module[property] !== 'undefined'
+}
+
+const runtimeFeaturesByExportedProperty = /** @type {const} */ (['markAsUncloneable', 'zstd'])
+
+/** @type {Record<RuntimeFeatureByExportedProperty, [NodeModuleName, string]>} */
+const exportedPropertyLookup = {
+  markAsUncloneable: ['node:worker_threads', 'markAsUncloneable'],
+  zstd: ['node:zlib', 'createZstdDecompress']
+}
+
+/** @typedef {typeof runtimeFeaturesByExportedProperty[number]} RuntimeFeatureByExportedProperty */
+
+const runtimeFeaturesAsNodeModule = /** @type {const} */ (['crypto', 'sqlite'])
+/** @typedef {typeof runtimeFeaturesAsNodeModule[number]} RuntimeFeatureByNodeModule */
+
+const features = /** @type {const} */ ([
+  ...runtimeFeaturesAsNodeModule,
+  ...runtimeFeaturesByExportedProperty
+])
+
+/** @typedef {typeof features[number]} Feature */
+
+/**
+ * @param {Feature} feature
+ * @returns {boolean}
+ */
+function detectRuntimeFeature (feature) {
+  if (runtimeFeaturesAsNodeModule.includes(/** @type {RuntimeFeatureByNodeModule} */ (feature))) {
+    return detectRuntimeFeatureByNodeModule(`node:${feature}`)
+  } else if (runtimeFeaturesByExportedProperty.includes(/** @type {RuntimeFeatureByExportedProperty} */ (feature))) {
+    const [moduleName, property] = exportedPropertyLookup[feature]
+    return detectRuntimeFeatureByExportedProperty(moduleName, property)
+  }
+  throw new TypeError(`unknown feature: ${feature}`)
+}
+
+/**
+ * @class
+ * @name RuntimeFeatures
+ */
+class RuntimeFeatures {
+  /** @type {Map<Feature, boolean>} */
+  #map = new Map()
+
+  /**
+   * Clears all cached feature detections.
+   */
+  clear () {
+    this.#map.clear()
+  }
+
+  /**
+   * @param {Feature} feature
+   * @returns {boolean}
+   */
+  has (feature) {
+    return (
+      this.#map.get(feature) ?? this.#detectRuntimeFeature(feature)
+    )
+  }
+
+  /**
+   * @param {Feature} feature
+   * @param {boolean} value
+   */
+  set (feature, value) {
+    if (features.includes(feature) === false) {
+      throw new TypeError(`unknown feature: ${feature}`)
+    }
+    this.#map.set(feature, value)
+  }
+
+  /**
+   * @param {Feature} feature
+   * @returns {boolean}
+   */
+  #detectRuntimeFeature (feature) {
+    const result = detectRuntimeFeature(feature)
+    this.#map.set(feature, result)
+    return result
+  }
+}
+
+const instance = new RuntimeFeatures()
+
+module.exports.runtimeFeatures = instance
+module.exports.default = instance