From fe1c53bd2d76ce6a8196ec33929ddcc3af0331b7 Mon Sep 17 00:00:00 2001
From: Simon Giesecke <sgiesecke@mozilla.com>
Date: Wed, 16 Dec 2020 19:10:06 +0000
Subject: [PATCH] Bug 1679987 - Convert tokenizer specializations from classes
 to type aliases. r=xpcom-reviewers,nika,necko-reviewers

Currently, the tokenizer specializations are subclasses of the generic base
template nsTCharSeparatedTokenizer. This is unnecessary with C++11 type aliases,
as those subclasses only delegate to the base constructor.

NS_TokenizerIgnoreNothing is introduced to replace several functions with
the same effect across the codebase.

Differential Revision: https://phabricator.services.mozilla.com/D98306
---
 dom/indexedDB/KeyPath.cpp                     |  8 ++--
 dom/quota/ActorsParent.cpp                    |  5 +--
 .../antitracking/URLDecorationStripper.cpp    |  5 +--
 xpcom/ds/nsCharSeparatedTokenizer.h           | 38 +++++++++----------
 4 files changed, 25 insertions(+), 31 deletions(-)

diff --git a/dom/indexedDB/KeyPath.cpp b/dom/indexedDB/KeyPath.cpp
index bb26d7eaf068..819bd8abed4c 100644
--- a/dom/indexedDB/KeyPath.cpp
+++ b/dom/indexedDB/KeyPath.cpp
@@ -26,9 +26,8 @@ namespace mozilla::dom::indexedDB {
 
 namespace {
 
-inline bool IgnoreWhitespace(char16_t c) { return false; }
-
-typedef nsCharSeparatedTokenizerTemplate<IgnoreWhitespace> KeyPathTokenizer;
+using KeyPathTokenizer =
+    nsCharSeparatedTokenizerTemplate<NS_TokenizerIgnoreNothing>;
 
 bool IsValidKeyPathString(const nsAString& aKeyPath) {
   NS_ASSERTION(!aKeyPath.IsVoid(), "What?");
@@ -463,7 +462,8 @@ KeyPath KeyPath::DeserializeFromString(const nsAString& aString) {
     // We use a comma in the beginning to indicate that it's an array of
     // key paths. This is to be able to tell a string-keypath from an
     // array-keypath which contains only one item.
-    nsCharSeparatedTokenizerTemplate<IgnoreWhitespace> tokenizer(aString, ',');
+    nsCharSeparatedTokenizerTemplate<NS_TokenizerIgnoreNothing> tokenizer(
+        aString, ',');
     tokenizer.nextToken();
     while (tokenizer.hasMoreTokens()) {
       keyPath.mStrings.AppendElement(tokenizer.nextToken());
diff --git a/dom/quota/ActorsParent.cpp b/dom/quota/ActorsParent.cpp
index b48b84b8ab34..94a49a27b57c 100644
--- a/dom/quota/ActorsParent.cpp
+++ b/dom/quota/ActorsParent.cpp
@@ -2213,9 +2213,8 @@ class MOZ_STACK_CLASS OriginParser final {
   enum ResultType { InvalidOrigin, ObsoleteOrigin, ValidOrigin };
 
  private:
-  static bool IgnoreWhitespace(char16_t /* aChar */) { return false; }
-
-  typedef nsCCharSeparatedTokenizerTemplate<IgnoreWhitespace> Tokenizer;
+  using Tokenizer =
+      nsCCharSeparatedTokenizerTemplate<NS_TokenizerIgnoreNothing>;
 
   enum SchemeType { eNone, eFile, eAbout, eChrome };
 
diff --git a/toolkit/components/antitracking/URLDecorationStripper.cpp b/toolkit/components/antitracking/URLDecorationStripper.cpp
index 3c10458f7772..abf316c72226 100644
--- a/toolkit/components/antitracking/URLDecorationStripper.cpp
+++ b/toolkit/components/antitracking/URLDecorationStripper.cpp
@@ -16,8 +16,6 @@
 namespace {
 static const char* kPrefName =
     "privacy.restrict3rdpartystorage.url_decorations";
-
-inline bool IgnoreWhitespace(char16_t c) { return false; }
 }  // namespace
 
 namespace mozilla {
@@ -36,7 +34,8 @@ nsresult URLDecorationStripper::StripTrackingIdentifiers(nsIURI* aURI,
   int32_t queryBegins = path.FindChar('?');
   // Only positive values are valid since the path must begin with a '/'.
   if (queryBegins > 0) {
-    typedef nsCharSeparatedTokenizerTemplate<IgnoreWhitespace> Tokenizer;
+    typedef nsCharSeparatedTokenizerTemplate<NS_TokenizerIgnoreNothing>
+        Tokenizer;
 
     Tokenizer tokenizer(tokenList, ' ');
     nsAutoString token;
diff --git a/xpcom/ds/nsCharSeparatedTokenizer.h b/xpcom/ds/nsCharSeparatedTokenizer.h
index 7685fb7681c4..1cdfae1f0fd7 100644
--- a/xpcom/ds/nsCharSeparatedTokenizer.h
+++ b/xpcom/ds/nsCharSeparatedTokenizer.h
@@ -146,35 +146,31 @@ class nsTCharSeparatedTokenizer {
  private:
   mozilla::RangedPtr<const CharType> mIter;
   const mozilla::RangedPtr<const CharType> mEnd;
-  CharType mSeparatorChar;
+  const CharType mSeparatorChar;
   bool mWhitespaceBeforeFirstToken;
   bool mWhitespaceAfterCurrentToken;
   bool mSeparatorAfterCurrentToken;
   bool mSeparatorOptional;
 };
 
-template <bool IsWhitespace(char16_t) = NS_IsAsciiWhitespace>
-class nsCharSeparatedTokenizerTemplate
-    : public nsTCharSeparatedTokenizer<nsDependentSubstring, IsWhitespace> {
- public:
-  nsCharSeparatedTokenizerTemplate(const nsAString& aSource,
-                                   char16_t aSeparatorChar, uint32_t aFlags = 0)
-      : nsTCharSeparatedTokenizer<nsDependentSubstring, IsWhitespace>(
-            aSource, aSeparatorChar, aFlags) {}
-};
+constexpr bool NS_TokenizerIgnoreNothing(char16_t) { return false; }
 
-typedef nsCharSeparatedTokenizerTemplate<> nsCharSeparatedTokenizer;
+template <bool IsWhitespace(char16_t), typename CharType>
+using nsTCharSeparatedTokenizerTemplate =
+    nsTCharSeparatedTokenizer<nsTDependentSubstring<CharType>, IsWhitespace>;
 
-template <bool IsWhitespace(char16_t) = NS_IsAsciiWhitespace>
-class nsCCharSeparatedTokenizerTemplate
-    : public nsTCharSeparatedTokenizer<nsDependentCSubstring, IsWhitespace> {
- public:
-  nsCCharSeparatedTokenizerTemplate(const nsACString& aSource,
-                                    char aSeparatorChar, uint32_t aFlags = 0)
-      : nsTCharSeparatedTokenizer<nsDependentCSubstring, IsWhitespace>(
-            aSource, aSeparatorChar, aFlags) {}
-};
+template <bool IsWhitespace(char16_t)>
+using nsCharSeparatedTokenizerTemplate =
+    nsTCharSeparatedTokenizerTemplate<IsWhitespace, char16_t>;
 
-typedef nsCCharSeparatedTokenizerTemplate<> nsCCharSeparatedTokenizer;
+using nsCharSeparatedTokenizer =
+    nsCharSeparatedTokenizerTemplate<NS_IsAsciiWhitespace>;
+
+template <bool IsWhitespace(char16_t)>
+using nsCCharSeparatedTokenizerTemplate =
+    nsTCharSeparatedTokenizerTemplate<IsWhitespace, char>;
+
+using nsCCharSeparatedTokenizer =
+    nsCCharSeparatedTokenizerTemplate<NS_IsAsciiWhitespace>;
 
 #endif /* __nsCharSeparatedTokenizer_h */