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+TESTING INDENT SCRIPTS
+
+We'll use FILETYPE for the filetype name here.
+
+
+FORMAT OF THE FILETYPE.IN FILE
+
+First of all, create a FILETYPE.in file.  It should contain:
+
+- A modeline setting the 'filetype' and any other option values.
+  This must work like a comment for FILETYPE.  E.g. for vim:
+	" vim: set ft=vim sw=4 :
+
+- At least one block of lines to indent, prefixed with START_INDENT and
+  followed by END_INDENT.  These lines must also look like a comment for your
+  FILETYPE.  You would normally leave out all indent, so that the effect of
+  the indent command results in adding indent.  Example:
+
+	" START_INDENT
+	func Some()
+	let x = 1
+	endfunc
+	" END_INDENT
+
+- Optionally, a line with INDENT_EXE, followed by a Vim command.  This will be
+  executed before indenting the lines.  Example:
+
+	" START_INDENT
+	" INDENT_EXE let g:vim_indent_cont = 6
+	let cmd =
+	      \ 'some '
+	      \ 'string'
+	" END_INDENT
+
+  Note that the command is not undone, you may need to reverse the effect for
+  the next block of lines.
+
+- Alternatively to indenting all the lines between START_INDENT and
+  END_INDENT, use a INDENT_AT line, which specifies a pattern to find the line
+  to indent.  Example:
+
+	" START_INDENT
+	" INDENT_AT  this-line
+	func Some()
+	let f = x " this-line
+	endfunc
+	" END_INDENT
+
+  Alternatively you can use INDENT_NEXT to indent the line below the matching
+  pattern:
+
+	" START_INDENT
+	" INDENT_NEXT  next-line
+	func Some()
+	" next-line
+	let f = x
+	endfunc
+	" END_INDENT
+
+  Or use INDENT_PREV to indent the line above the matching pattern:
+
+	" START_INDENT
+	" INDENT_PREV  prev-line
+	func Some()
+      	let f = x
+	" prev-line
+	endfunc
+	" END_INDENT
+
+It's best to keep the whole file valid for FILETYPE, so that syntax
+highlighting works normally, and any indenting that depends on the syntax
+highlighting also works.
+
+
+RUNNING THE TEST
+
+Before running the test, create a FILETYPE.ok file.  You can leave it empty at
+first.
+
+Now run "make test".  After Vim has done the indenting you will see a
+FILETYPE.fail file.  This contains the actual result of indenting, and it's
+different from the FILETYPE.ok file.
+
+Check the contents of the FILETYPE.fail file.  If it is perfectly OK, then
+rename it to overwrite the FILETYPE.ok file. If you now run "make test" again,
+the test will pass and create a FILETYPE.out file, which is identical to the
+FILETYPE.ok file.
+
+If you try to run "make test" again you will notice that nothing happens,
+because the FILETYPE.out file already exists.  Delete it, or do "make clean",
+so that the text runs again.  If you edit the FILETYPE.in file, so that it's
+newer than the FILETYPE.out file, the test will also run.