From e09c1e4db92e28a332f55aa3c80ceb44f4b74287 Mon Sep 17 00:00:00 2001 From: tsepez Date: Mon, 11 Apr 2016 18:01:13 -0700 Subject: Make CFX_{Byte,Wide}String::Remove() no-touch if possible Don't try to copy the string until we are sure we need to change it. Review URL: https://codereview.chromium.org/1877993002 --- core/fxcrt/fx_basic_bstring_unittest.cpp | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'core/fxcrt/fx_basic_bstring_unittest.cpp') diff --git a/core/fxcrt/fx_basic_bstring_unittest.cpp b/core/fxcrt/fx_basic_bstring_unittest.cpp index 8c72b2a054..ea7e17f1f1 100644 --- a/core/fxcrt/fx_basic_bstring_unittest.cpp +++ b/core/fxcrt/fx_basic_bstring_unittest.cpp @@ -333,6 +333,35 @@ TEST(fxcrt, ByteStringRemove) { EXPECT_EQ("", empty); } +TEST(fxcrt, ByteStringRemoveCopies) { + CFX_ByteString freed("FREED"); + const FX_CHAR* old_buffer = freed.c_str(); + + // No change with single reference - no copy. + freed.Remove('Q'); + EXPECT_EQ("FREED", freed); + EXPECT_EQ(old_buffer, freed.c_str()); + + // Change with single reference - no copy. + freed.Remove('E'); + EXPECT_EQ("FRD", freed); + EXPECT_EQ(old_buffer, freed.c_str()); + + // No change with multiple references - no copy. + CFX_ByteString shared(freed); + freed.Remove('Q'); + EXPECT_EQ("FRD", freed); + EXPECT_EQ(old_buffer, freed.c_str()); + EXPECT_EQ(old_buffer, shared.c_str()); + + // Change with multiple references -- must copy. + freed.Remove('D'); + EXPECT_EQ("FR", freed); + EXPECT_NE(old_buffer, freed.c_str()); + EXPECT_EQ("FRD", shared); + EXPECT_EQ(old_buffer, shared.c_str()); +} + TEST(fxcrt, ByteStringReplace) { CFX_ByteString fred("FRED"); fred.Replace("FR", "BL"); -- cgit v1.2.3