[regexp] Escape newlines when setting [[OriginalSource]]

This escapes LineTerminator characters in a regexp pattern when
creating the string that will be stored in the [[OriginalSource]] slot.

As an example, the source property for all following objects will equal
"\n" (a '\' character followed by 'n'):

  /\n/
  new RegExp("\n")
  new RegExp("\\n")

Bug: v8:1982, chromium:855009
Change-Id: I3b539497a0697e3d51ec969cae49308b0b312a19
Reviewed-on: https://chromium-review.googlesource.com/c/1384316
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Mathias Bynens <mathias@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58387}

src/objects.cc

@@ -16752,33 +16752,52 @@ Handle<JSRegExp> JSRegExp::Copy(Handle<JSRegExp> regexp) {
   return Handle<JSRegExp>::cast(isolate->factory()->CopyJSObject(regexp));
 }
 
+namespace {
 
 template <typename Char>
-inline int CountRequiredEscapes(Handle<String> source) {
+int CountRequiredEscapes(Handle<String> source) {
   DisallowHeapAllocation no_gc;
   int escapes = 0;
   Vector<const Char> src = source->GetCharVector<Char>(no_gc);
   for (int i = 0; i < src.length(); i++) {
-    if (src[i] == '\\') {
+    const Char c = src[i];
+    if (c == '\\') {
       // Escape. Skip next character;
       i++;
-    } else if (src[i] == '/') {
+    } else if (c == '/') {
       // Not escaped forward-slash needs escape.
       escapes++;
+    } else if (c == '\n') {
+      escapes++;
+    } else if (c == '\r') {
+      escapes++;
+    } else if (static_cast<int>(c) == 0x2028) {
+      escapes += std::strlen("\\u2028") - 1;
+    } else if (static_cast<int>(c) == 0x2029) {
+      escapes += std::strlen("\\u2029") - 1;
+    } else {
+      DCHECK(!unibrow::IsLineTerminator(static_cast<unibrow::uchar>(c)));
     }
   }
   return escapes;
 }
 
+template <typename Char>
+void WriteStringToCharVector(Vector<Char> v, int* d, const char* string) {
+  int s = 0;
+  while (string[s] != '\0') v[(*d)++] = string[s++];
+}
 
 template <typename Char, typename StringType>
-inline Handle<StringType> WriteEscapedRegExpSource(Handle<String> source,
-                                                   Handle<StringType> result) {
+Handle<StringType> WriteEscapedRegExpSource(Handle<String> source,
+                                            Handle<StringType> result) {
   DisallowHeapAllocation no_gc;
   Vector<const Char> src = source->GetCharVector<Char>(no_gc);
   Vector<Char> dst(result->GetChars(no_gc), result->length());
   int s = 0;
   int d = 0;
+  // TODO(v8:1982): Fully implement
+  // https://tc39.github.io/ecma262/#sec-escaperegexppattern
   while (s < src.length()) {
     if (src[s] == '\\') {
       // Escape. Copy this and next character.
@@ -16787,6 +16806,22 @@ inline Handle<StringType> WriteEscapedRegExpSource(Handle<String> source,
     } else if (src[s] == '/') {
       // Not escaped forward-slash needs escape.
       dst[d++] = '\\';
+    } else if (src[s] == '\n') {
+      WriteStringToCharVector(dst, &d, "\\n");
+      s++;
+      continue;
+    } else if (src[s] == '\r') {
+      WriteStringToCharVector(dst, &d, "\\r");
+      s++;
+      continue;
+    } else if (static_cast<int>(src[s]) == 0x2028) {
+      WriteStringToCharVector(dst, &d, "\\u2028");
+      s++;
+      continue;
+    } else if (static_cast<int>(src[s]) == 0x2029) {
+      WriteStringToCharVector(dst, &d, "\\u2029");
+      s++;
+      continue;
     }
     dst[d++] = src[s++];
   }
@@ -16794,7 +16829,6 @@ inline Handle<StringType> WriteEscapedRegExpSource(Handle<String> source,
   return result;
 }
 
-
 MaybeHandle<String> EscapeRegExpSource(Isolate* isolate,
                                        Handle<String> source) {
   DCHECK(source->IsFlat());
@@ -16819,6 +16853,7 @@ MaybeHandle<String> EscapeRegExpSource(Isolate* isolate,
   }
 }
 
+}  // namespace
 
 // static
 MaybeHandle<JSRegExp> JSRegExp::Initialize(Handle<JSRegExp> regexp,

test/mjsunit/regexp.js

@@ -808,3 +808,19 @@ assertFalse(/^[\d-X-Z]*$/.test("234-XYZ-432"));
 
 assertFalse(/\uDB88|\uDBEC|aa/.test(""));
 assertFalse(/\uDB88|\uDBEC|aa/u.test(""));
+
+// EscapeRegExpPattern
+assertEquals("\\n", /\n/.source);
+assertEquals("\\n", new RegExp("\n").source);
+assertEquals("\\n", new RegExp("\\n").source);
+assertEquals("\\\\n", /\\n/.source);
+assertEquals("\\r", /\r/.source);
+assertEquals("\\r", new RegExp("\r").source);
+assertEquals("\\r", new RegExp("\\r").source);
+assertEquals("\\\\r", /\\r/.source);
+assertEquals("\\u2028", /\u2028/.source);
+assertEquals("\\u2028", new RegExp("\u2028").source);
+assertEquals("\\u2028", new RegExp("\\u2028").source);
+assertEquals("\\u2029", /\u2029/.source);
+assertEquals("\\u2029", new RegExp("\u2029").source);
+assertEquals("\\u2029", new RegExp("\\u2029").source);

test/test262/test262.status

@@ -479,9 +479,6 @@
   'built-ins/TypedArrayConstructors/internals/Set/key-is-out-of-bounds': [FAIL],
   'built-ins/TypedArrayConstructors/internals/Set/BigInt/key-is-out-of-bounds': [FAIL],
 
-  # https://bugs.chromium.org/p/v8/issues/detail?id=5329
-  'built-ins/RegExp/prototype/source/value-line-terminator': [FAIL],
-
   # https://bugs.chromium.org/p/v8/issues/detail?id=5112
   'annexB/language/eval-code/direct/func-block-decl-eval-func-no-skip-try': [FAIL],
   'annexB/language/eval-code/direct/func-if-decl-else-decl-a-eval-func-no-skip-try': [FAIL],

test/webkit/fast/regex/toString-expected.txt

@@ -43,13 +43,13 @@ PASS testForwardSlash("x/x/x", "x\/x\/x"); is true
 PASS testForwardSlash("x\/x/x", "x\/x\/x"); is true
 PASS testForwardSlash("x/x\/x", "x\/x\/x"); is true
 PASS testForwardSlash("x\/x\/x", "x\/x\/x"); is true
-FAIL testLineTerminator("\n"); should be false. Was true.
+PASS testLineTerminator("\n"); is false
 PASS testLineTerminator("\\n"); is false
-FAIL testLineTerminator("\r"); should be false. Was true.
+PASS testLineTerminator("\r"); is false
 PASS testLineTerminator("\\r"); is false
-FAIL testLineTerminator("\u2028"); should be false. Was true.
+PASS testLineTerminator("\u2028"); is false
 PASS testLineTerminator("\\u2028"); is false
-FAIL testLineTerminator("\u2029"); should be false. Was true.
+PASS testLineTerminator("\u2029"); is false
 PASS testLineTerminator("\\u2029"); is false
 FAIL RegExp('[/]').source should be [/]. Was [\/].
 PASS RegExp('\\[/]').source is '\\[\\/]'