Add recursive pattern matching for subfolders in file_enumerator.

base/files/file_enumerator.h

Index: base/files/file_enumerator.h
diff --git a/base/files/file_enumerator.h b/base/files/file_enumerator.h
index 7cac8dd9d457f86366ea54adc1688d36f9121ed9..4f3ee57a8c555c70fac5d6e2bde900137ba9101e 100644
--- a/base/files/file_enumerator.h
+++ b/base/files/file_enumerator.h
@@ -84,6 +84,17 @@ class BASE_EXPORT FileEnumerator {
 #endif
   };
 
+  // Search policy for intermediate folders.
+  enum class FolderSearchPolicy {
+    // Recursive search will pass through folders whose names match the
+    // pattern. Inside each one, all files will be returned. Folders with names
+    // that do not match the pattern will be ignored within their interior.
+    MATCH_ONLY,
+    // Recursive search will pass through every folder and perform pattern
+    // matching inside each one.
+    ALL,
+  };
+
   // |root_path| is the starting directory to search for. It may or may not end
   // in a slash.
   //
@@ -101,9 +112,6 @@ class BASE_EXPORT FileEnumerator {
   // since the underlying code uses OS-specific matching routines.  In general,
   // Windows matching is less featureful than others, so test there first.
   // If unspecified, this will match all files.
-  // NOTE: the pattern only matches the contents of root_path, not files in
-  // recursive subdirectories.
-  // TODO(erikkay): Fix the pattern matching to work at all levels.
   FileEnumerator(const FilePath& root_path,
                  bool recursive,
                  int file_type);
@@ -111,6 +119,11 @@ class BASE_EXPORT FileEnumerator {
                  bool recursive,
                  int file_type,
                  const FilePath::StringType& pattern);
+  FileEnumerator(const FilePath& root_path,
+                 bool recursive,
+                 int file_type,
+                 const FilePath::StringType& pattern,
+                 FolderSearchPolicy folder_search_policy);
   ~FileEnumerator();
 
   // Returns the next file or an empty string if there are no more results.
@@ -127,28 +140,27 @@ class BASE_EXPORT FileEnumerator {
   // Returns true if the given path should be skipped in enumeration.
   bool ShouldSkip(const FilePath& path);
 
+  bool IsTypeMatched(bool is_dir) const;
+
+  bool IsPatternMatched(const FilePath& src) const;
+
 #if defined(OS_WIN)
   // True when find_data_ is valid.
-  bool has_find_data_;
+  bool has_find_data_ = false;
   WIN32_FIND_DATA find_data_;
-  HANDLE find_handle_;
+  HANDLE find_handle_ = INVALID_HANDLE_VALUE;
 #elif defined(OS_POSIX)
-
-  // Read the filenames in source into the vector of DirectoryEntryInfo's
-  static bool ReadDirectory(std::vector<FileInfo>* entries,
-                            const FilePath& source, bool show_links);
-
   // The files in the current directory
   std::vector<FileInfo> directory_entries_;
 
   // The next entry to use from the directory_entries_ vector
   size_t current_directory_entry_;
 #endif
-
   FilePath root_path_;
-  bool recursive_;
-  int file_type_;
-  FilePath::StringType pattern_;  // Empty when we want to find everything.
+  const bool recursive_;
+  const int file_type_;
+  FilePath::StringType pattern_;
+  const FolderSearchPolicy folder_search_policy_;
 
   // A stack that keeps track of which subdirectories we still need to
   // enumerate in the breadth-first search.