refactor: create extractFilter function

Author: sapphi-red

packages/vite/src/node/plugins/index.ts

@@ -187,26 +187,19 @@ export function getCachedFilterForPlugin<
   let filter: PluginFilter | TransformHookFilter | undefined
   switch (hookName) {
     case 'resolveId': {
-      const rawFilter =
-        typeof plugin.resolveId === 'object'
-          ? plugin.resolveId.filter?.id
-          : undefined
+      const rawFilter = extractFilter(plugin.resolveId)?.id
       filters.resolveId = createIdFilter(rawFilter)
       filter = filters.resolveId
       break
     }
     case 'load': {
-      const rawFilter =
-        typeof plugin.load === 'object' ? plugin.load.filter?.id : undefined
+      const rawFilter = extractFilter(plugin.load)?.id
       filters.load = createIdFilter(rawFilter)
       filter = filters.load
       break
     }
     case 'transform': {
-      const rawFilters =
-        typeof plugin.transform === 'object'
-          ? plugin.transform.filter
-          : undefined
+      const rawFilters = extractFilter(plugin.transform)
       filters.transform = createFilterForTransform(
         rawFilters?.id,
         rawFilters?.code,
@@ -218,6 +211,12 @@ export function getCachedFilterForPlugin<
   return filter as FilterForPluginValue[H] | undefined
 }
 
+function extractFilter<T extends Function, F>(
+  hook: ObjectHook<T, { filter?: F }> | undefined,
+) {
+  return hook && 'filter' in hook && hook.filter ? hook.filter : undefined
+}
+
 // Same as `@rollup/plugin-alias` default resolver, but we attach additional meta
 // if we can't resolve to something, which will error in `importAnalysis`
 export const viteAliasCustomResolver: ResolverFunction = async function (