Write new Starts/EndsWith and convert FilePath functions to StringPiece.
When I moved StartsWith and EndsWith to the base namespace it became apparent that the bool parameter was frequently a source of confusion, and that the second argument is almost always a constant that we then convert to a string.
This adds new versions of StartsWith/EndsWith that takes an enum for case sensitivity and string pieces for the string inputs.
The existing functions used a locale-dependent case insensitive comparison that is marked with an old bug number that such comparisons are probably wrong. With this change, I moved the case insensitive comparisons to ASCII ones.
Only callers in base are updated. The rest of the calls go through a compatibility layer.
The compatibility layer keeps the local-dependent compares for the 16-bit string comparisons to avoid breaking things subtly. There are relatively few calls to the 16-bit version, and most use constants for the prefix/suffix (which wouldn't be affected by the locale), so there should be few callers to audit in a later pass to go to pure ASCII comparisons.
The 8-bit versions now always use the ASCII case-insensitive comparisons. This should be the only change in this patch that can affect the behavior of the program. Code doing locale-dependent 8-bit tolower() calls (what the old code ended up doing) is almost certainly wrong. UTF-8 strings will be mangled. The only 8-bit non-UTF-8 strings we have are typically Posix file paths and Posix file paths are case-sensitive. I'm not very concerned about regressions from this change.
Use StringPiece in FilePath for input arguments. This wasn't done before because we had no StringPiece16 until more recently. Constants are frequently passed as input to some of the functions, especially Append, so this will save some string allocations. Unfortunately, this is more likely to affect unit tests that the real browser. This is combined with the StartsWith/EndsWith changes because I started changing FilePath when updating its use of StartsWith.
The FilePath changes should have no observable effect on the product.
BUG=24917
Review URL: https://codereview.chromium.org/1182453004
Cr-Commit-Position: refs/heads/master@{#334555}
CrOS-Libchrome-Original-Commit: 89365dc80aa9ea343cea0fe48fdeb702b23726a2
diff --git a/base/files/file_path.h b/base/files/file_path.h
index 0c84af6..25b8391 100644
--- a/base/files/file_path.h
+++ b/base/files/file_path.h
@@ -112,7 +112,7 @@
#include "base/compiler_specific.h"
#include "base/containers/hash_tables.h"
#include "base/strings/string16.h"
-#include "base/strings/string_piece.h" // For implicit conversions.
+#include "base/strings/string_piece.h"
#include "build/build_config.h"
// Windows-style drive letter support and pathname separator characters can be
@@ -144,6 +144,7 @@
typedef std::wstring StringType;
#endif // OS_WIN
+ typedef BasicStringPiece<StringType> StringPieceType;
typedef StringType::value_type CharType;
// Null-terminated array of separators used to separate components in
@@ -166,7 +167,7 @@
FilePath();
FilePath(const FilePath& that);
- explicit FilePath(const StringType& path);
+ explicit FilePath(StringPieceType path);
~FilePath();
FilePath& operator=(const FilePath& that);
@@ -268,25 +269,23 @@
// path == "C:\pics\jojo" suffix == " (1)", returns "C:\pics\jojo (1)"
// path == "C:\pics.old\jojo" suffix == " (1)", returns "C:\pics.old\jojo (1)"
FilePath InsertBeforeExtension(
- const StringType& suffix) const WARN_UNUSED_RESULT;
+ StringPieceType suffix) const WARN_UNUSED_RESULT;
FilePath InsertBeforeExtensionASCII(
- const base::StringPiece& suffix) const WARN_UNUSED_RESULT;
+ StringPiece suffix) const WARN_UNUSED_RESULT;
// Adds |extension| to |file_name|. Returns the current FilePath if
// |extension| is empty. Returns "" if BaseName() == "." or "..".
- FilePath AddExtension(
- const StringType& extension) const WARN_UNUSED_RESULT;
+ FilePath AddExtension(StringPieceType extension) const WARN_UNUSED_RESULT;
// Replaces the extension of |file_name| with |extension|. If |file_name|
// does not have an extension, then |extension| is added. If |extension| is
// empty, then the extension is removed from |file_name|.
// Returns "" if BaseName() == "." or "..".
- FilePath ReplaceExtension(
- const StringType& extension) const WARN_UNUSED_RESULT;
+ FilePath ReplaceExtension(StringPieceType extension) const WARN_UNUSED_RESULT;
// Returns true if the file path matches the specified extension. The test is
// case insensitive. Don't forget the leading period if appropriate.
- bool MatchesExtension(const StringType& extension) const;
+ bool MatchesExtension(StringPieceType extension) const;
// Returns a FilePath by appending a separator and the supplied path
// component to this object's path. Append takes care to avoid adding
@@ -294,7 +293,7 @@
// If this object's path is kCurrentDirectory, a new FilePath corresponding
// only to |component| is returned. |component| must be a relative path;
// it is an error to pass an absolute path.
- FilePath Append(const StringType& component) const WARN_UNUSED_RESULT;
+ FilePath Append(StringPieceType component) const WARN_UNUSED_RESULT;
FilePath Append(const FilePath& component) const WARN_UNUSED_RESULT;
// Although Windows StringType is std::wstring, since the encoding it uses for
@@ -303,8 +302,7 @@
// On Linux, although it can use any 8-bit encoding for paths, we assume that
// ASCII is a valid subset, regardless of the encoding, since many operating
// system paths will always be ASCII.
- FilePath AppendASCII(const base::StringPiece& component)
- const WARN_UNUSED_RESULT;
+ FilePath AppendASCII(StringPiece component) const WARN_UNUSED_RESULT;
// Returns true if this FilePath contains an absolute path. On Windows, an
// absolute path begins with either a drive letter specification followed by
@@ -388,14 +386,14 @@
// on parts of a file path, e.g., just the extension.
// CompareIgnoreCase() returns -1, 0 or 1 for less-than, equal-to and
// greater-than respectively.
- static int CompareIgnoreCase(const StringType& string1,
- const StringType& string2);
- static bool CompareEqualIgnoreCase(const StringType& string1,
- const StringType& string2) {
+ static int CompareIgnoreCase(StringPieceType string1,
+ StringPieceType string2);
+ static bool CompareEqualIgnoreCase(StringPieceType string1,
+ StringPieceType string2) {
return CompareIgnoreCase(string1, string2) == 0;
}
- static bool CompareLessIgnoreCase(const StringType& string1,
- const StringType& string2) {
+ static bool CompareLessIgnoreCase(StringPieceType string1,
+ StringPieceType string2) {
return CompareIgnoreCase(string1, string2) < 0;
}
@@ -405,14 +403,14 @@
// http://developer.apple.com/mac/library/technotes/tn/tn1150.html#UnicodeSubtleties
// for further comments.
// Returns the epmty string if the conversion failed.
- static StringType GetHFSDecomposedForm(const FilePath::StringType& string);
+ static StringType GetHFSDecomposedForm(StringPieceType string);
// Special UTF-8 version of FastUnicodeCompare. Cf:
// http://developer.apple.com/mac/library/technotes/tn/tn1150.html#StringComparisonAlgorithm
// IMPORTANT: The input strings must be in the special HFS decomposed form!
// (cf. above GetHFSDecomposedForm method)
- static int HFSFastUnicodeCompare(const StringType& string1,
- const StringType& string2);
+ static int HFSFastUnicodeCompare(StringPieceType string1,
+ StringPieceType string2);
#endif
#if defined(OS_ANDROID)