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+To: vim_dev@googlegroups.com
+Subject: Patch 7.3.392
+Fcc: outbox
+From: Bram Moolenaar <Bram@moolenaar.net>
+Mime-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+------------
+
+Patch 7.3.392
+Problem:    When setting 'undofile' while the file is already loaded but
+	    unchanged, try reading the undo file. (Andy Wokula)
+Solution:   Compute a checksum of the text when 'undofile' is set. (Christian
+	    Brabandt)
+Files:	    src/option.c, src/testdir/test72.in, src/testdir/test72.ok
+
+
+*** ../vim-7.3.391/src/option.c	2011-11-30 11:31:25.000000000 +0100
+--- src/option.c	2012-01-04 19:34:11.000000000 +0100
+***************
+*** 7516,7521 ****
+--- 7516,7545 ----
+  	compatible_set();
+      }
+  
++ #ifdef FEAT_PERSISTENT_UNDO
++     /* 'undofile' */
++     else if ((int *)varp == &curbuf->b_p_udf || (int *)varp == &p_udf)
++     {
++ 	char_u	hash[UNDO_HASH_SIZE];
++ 	buf_T	*save_curbuf = curbuf;
++ 
++ 	for (curbuf = firstbuf; curbuf != NULL; curbuf = curbuf->b_next)
++ 	{
++ 	    /* When 'undofile' is set globally: for every buffer, otherwise
++ 	     * only for the current buffer: Try to read in the undofile, if
++ 	     * one exists and the buffer wasn't changed. */
++ 	    if ((curbuf == save_curbuf
++ 				|| (opt_flags & OPT_GLOBAL) || opt_flags == 0)
++ 		    && !curbufIsChanged())
++ 	    {
++ 		u_compute_hash(hash);
++ 		u_read_undo(NULL, hash, curbuf->b_fname);
++ 	    }
++ 	}
++ 	curbuf = save_curbuf;
++     }
++ #endif
++ 
+      /* 'list', 'number' */
+      else if ((int *)varp == &curwin->w_p_list
+  	  || (int *)varp == &curwin->w_p_nu
+*** ../vim-7.3.391/src/testdir/test72.in	2010-08-15 21:57:29.000000000 +0200
+--- src/testdir/test72.in	2012-01-04 19:04:17.000000000 +0100
+***************
+*** 51,56 ****
+--- 51,62 ----
+  :e Xtestfile
+  uuu:w >>test.out
+  :"
++ :" Test that reading the undofiles when setting undofile works
++ :set noundofile ul=0
++ i
++ u:e! Xtestfile
++ :set undofile ul=100
++ uuuuuu:w >>test.out
+  :" And now with encryption, cryptmethod=zip
+  :e! Xtestfile
+  :set undofile cm=zip
+*** ../vim-7.3.391/src/testdir/test72.ok	2010-08-15 21:57:29.000000000 +0200
+--- src/testdir/test72.ok	2012-01-04 19:04:17.000000000 +0100
+***************
+*** 7,12 ****
+--- 7,22 ----
+  eight
+  nine
+  ten
++ one
++ two
++ three
++ four
++ five
++ six
++ seven
++ eight
++ nine
++ ten
+  monday
+  wednesday
+  thursday
+*** ../vim-7.3.391/src/version.c	2012-01-04 14:35:31.000000000 +0100
+--- src/version.c	2012-01-04 19:33:41.000000000 +0100
+***************
+*** 716,717 ****
+--- 716,719 ----
+  {   /* Add new patch number below this line */
++ /**/
++     392,
+  /**/
+
+-- 
+BROTHER MAYNARD: Armaments Chapter Two Verses Nine to Twenty One.
+ANOTHER MONK:    And St.  Attila raised his hand grenade up on high saying "O
+                 Lord bless this thy hand grenade that with it thou mayest
+                 blow thine enemies to tiny bits, in thy mercy. "and the Lord
+                 did grin and people did feast upon the lambs and sloths and
+                 carp and anchovies and orang-utans and breakfast cereals and
+                 fruit bats and...
+BROTHER MAYNARD: Skip a bit brother ...
+                 "Monty Python and the Holy Grail" PYTHON (MONTY) PICTURES LTD
+
+ /// Bram Moolenaar -- Bram@Moolenaar.net -- http://www.Moolenaar.net   \\\
+///        sponsor Vim, vote for features -- http://www.Vim.org/sponsor/ \\\
+\\\  an exciting new programming language -- http://www.Zimbu.org        ///
+ \\\            help me help AIDS victims -- http://ICCF-Holland.org    ///