Fixes #5377 : Split packager on single @ regardless of escaped @@s. (#5379)

AUTHORS

@@ -300,3 +300,4 @@ a license to everyone to use it as detailed in LICENSE.)
 * Nikolay Zapolnov <zapolnov@gmail.com>
 * Nazar Mokrynskyi <nazar@mokrynskyi.com>
 * Yury Delendik <ydelendik@mozilla.com> (copyright owned by Mozilla Foundation)
+* Kenneth Perry <thothonegan@gmail.com>

tests/test_browser.py

@@ -138,6 +138,9 @@ If manually bisecting:
     absolute_src_path2 = os.path.join(self.get_dir(), '.somefile.txt').replace('\\', '/')
     open(absolute_src_path2, 'w').write('''load me right before running the code please''')
     
+    absolute_src_path3 = os.path.join(self.get_dir(), 'some@file.txt').replace('\\', '/')
+    open(absolute_src_path3, 'w').write('''load me right before running the code please''')
+    
     def make_main(path):
       print 'make main at', path
       path = path.replace('\\', '\\\\').replace('"', '\\"') # Escape tricky path name for use inside a C string.
@@ -174,7 +177,9 @@ If manually bisecting:
       (absolute_src_path + "@/", "somefile.txt"),
       ("somefile.txt@/directory/file.txt", "/directory/file.txt"),
       ("somefile.txt@/directory/file.txt", "directory/file.txt"),
-      (absolute_src_path + "@/directory/file.txt", "directory/file.txt")]
+      (absolute_src_path + "@/directory/file.txt", "directory/file.txt"),
+      ("some@@file.txt@other.txt", "other.txt"),
+      ("some@@file.txt@some@@otherfile.txt", "some@otherfile.txt")]
 
     for test in test_cases:
       (srcpath, dstpath) = test

tools/file_packager.py

@@ -164,12 +164,14 @@ for arg in sys.argv[2:]:
     leading = ''
   elif leading == 'preload' or leading == 'embed':
     mode = leading
-    uses_at_notation = '@' in arg.replace('@@', '') # '@@' in input string means there is an actual @ character, a single '@' means the 'src@dst' notation.
-    arg = arg.replace('@@', '@')
+    at_position = arg.replace('@@', '__').find('@') # position of @ if we're doing 'src@dst'. '__' is used to keep the index same with the original if they escaped with '@@'.
+    uses_at_notation = (at_position != -1) # '@@' in input string means there is an actual @ character, a single '@' means the 'src@dst' notation.
+    
     if uses_at_notation:
-      srcpath, dstpath = arg.split('@') # User is specifying destination filename explicitly.
+      srcpath = arg[0:at_position].replace('@@', '@') # split around the @
+      dstpath = arg[at_position+1:].replace('@@', '@')
     else:
-      srcpath = dstpath = arg # Use source path as destination path.
+      srcpath = dstpath = arg.replace('@@', '@') # Use source path as destination path.
     if os.path.isfile(srcpath) or os.path.isdir(srcpath):
       data_files.append({ 'srcpath': srcpath, 'dstpath': dstpath, 'mode': mode, 'explicit_dst_path': uses_at_notation })
     else: