Perf: reduce operations in normalizeDomain

Build/lib/normalize-domain.ts

@@ -6,28 +6,28 @@ import { normalizeTldtsOpt } from '../constants/loose-tldts-opt';
 
 type TldTsParsed = ReturnType<typeof tldts.parse>;
 
+/**
+ * Skipped the input non-empty check, the `domain` should not be empty.
+ */
+export function fastNormalizeDomain(domain: string, parsed: TldTsParsed = tldts.parse(domain, normalizeTldtsOpt)) {
+  if (parsed.isIp) return null;
+  // Private invalid domain (things like .tor, .dn42, etc)
+  if (!parsed.isIcann && !parsed.isPrivate) return null;
+
+  return parsed.hostname;
+}
+
 export function normalizeDomain(domain: string, parsed: TldTsParsed | null = null) {
   if (domain.length === 0) return null;
 
   parsed ??= tldts.parse(domain, normalizeTldtsOpt);
 
   if (parsed.isIp) return null;
-
-  let h = parsed.hostname;
-  if (h === null) return null;
   // Private invalid domain (things like .tor, .dn42, etc)
   if (!parsed.isIcann && !parsed.isPrivate) return null;
 
-  let sliceStart = 0;
+  // const h = parsed.hostname;
-  let sliceEnd = 0;
+  // if (h === null) return null;
 
-  if (h[0] === '.') sliceStart = 1;
+  return parsed.hostname;
-  // eslint-disable-next-line sukka/string/prefer-string-starts-ends-with -- performance
-  if (h[h.length - 1] === '.') sliceEnd = -1;
-
-  if (sliceStart !== 0 || sliceEnd !== 0) {
-    h = h.slice(sliceStart, sliceEnd);
-  }
-
-  return h.length > 0 ? h : null;
 }

Build/lib/parse-filter/domainlists.ts

@@ -1,5 +1,5 @@
 import picocolors from 'picocolors';
-import { normalizeDomain } from '../normalize-domain';
+import { fastNormalizeDomain } from '../normalize-domain';
 import { processLine } from '../process-line';
 import { onBlackFound } from './shared';
 import { fetchAssetsWithout304 } from '../fetch-assets';
@@ -9,7 +9,7 @@ function domainListLineCb(l: string, set: string[], includeAllSubDomain: boolean
   const line = processLine(l);
   if (!line) return;
 
-  const domain = normalizeDomain(line);
+  const domain = fastNormalizeDomain(line);
   if (!domain) return;
   if (domain !== line) {
     console.log(

Build/lib/parse-filter/filters.ts

@@ -3,7 +3,7 @@ import type { Span } from '../../trace';
 import { fetchAssetsWithout304 } from '../fetch-assets';
 import { onBlackFound, onWhiteFound } from './shared';
 import { createRetrieKeywordFilter as createKeywordFilter } from 'foxts/retrie';
-import { normalizeDomain } from '../normalize-domain';
+import { fastNormalizeDomain } from '../normalize-domain';
 import { looseTldtsOpt } from '../../constants/loose-tldts-opt';
 import tldts from 'tldts-experimental';
 import { NetworkFilter } from '@ghostery/adblocker';
@@ -227,7 +227,7 @@ export function parse($line: string, result: [string, ParseType], allowThirdPart
       && filter.isPlain() // isPlain() === !isRegex()
       && (!filter.isFullRegex())
     ) {
-      const hostname = normalizeDomain(filter.hostname);
+      const hostname = fastNormalizeDomain(filter.hostname);
       if (!hostname) {
         result[1] = ParseType.Null;
         return result;
@@ -421,6 +421,11 @@ export function parse($line: string, result: [string, ParseType], allowThirdPart
   }
 
   const sliced = (sliceStart > 0 || sliceEnd < 0) ? line.slice(sliceStart, sliceEnd === 0 ? undefined : sliceEnd) : line;
+  if (sliced.length === 0) {
+    result[1] = ParseType.Null;
+    return result;
+  }
+
   if (sliced.charCodeAt(0) === 45 /* - */) {
     // line.startsWith('-') is not a valid domain
     result[1] = ParseType.ErrorMessage;
@@ -437,7 +442,7 @@ export function parse($line: string, result: [string, ParseType], allowThirdPart
     return result;
   }
 
-  const domain = normalizeDomain(sliced);
+  const domain = fastNormalizeDomain(sliced);
 
   if (domain && domain === sliced) {
     result[0] = domain;

Build/lib/parse-filter/hosts.ts

@@ -1,6 +1,6 @@
 import type { Span } from '../../trace';
 import { fetchAssetsWithout304 } from '../fetch-assets';
-import { normalizeDomain } from '../normalize-domain';
+import { fastNormalizeDomain } from '../normalize-domain';
 import { processLine } from '../process-line';
 import { onBlackFound } from './shared';
 
@@ -14,7 +14,7 @@ function hostsLineCb(l: string, set: string[], includeAllSubDomain: boolean, met
   if (!_domain) {
     return;
   }
-  const domain = normalizeDomain(_domain);
+  const domain = fastNormalizeDomain(_domain);
   if (!domain) {
     return;
   }

Build/validate-gfwlist.ts

@@ -1,5 +1,5 @@
 import { processLine } from './lib/process-line';
-import { normalizeDomain } from './lib/normalize-domain';
+import { fastNormalizeDomain } from './lib/normalize-domain';
 import { HostnameSmolTrie } from './lib/trie';
 // import { Readable } from 'stream';
 import { parse } from 'csv-parse/sync';
@@ -54,7 +54,7 @@ export async function parseGfwList() {
       trie.add(line);
       continue;
     }
-    const d = normalizeDomain(line);
+    const d = fastNormalizeDomain(line);
     if (d) {
       trie.add(d);
       continue;

Source/stream.ts

@@ -879,7 +879,7 @@ export const HK: StreamService[] = [
   NOW_E,
   VIUTV,
   MYTV_SUPER,
-  HBO_ASIA,
+  HBO_ASIA
   // BILIBILI_INTL
 ];