Ticket #3068 (new enhancement)

Opened 11 years ago

Last modified 11 years ago

Vim's modeline support / tabulation settings per-file

Reported by: twasilczyk Owned by:
Priority: major Milestone: Future Releases
Component: mcedit Version: master
Keywords: tabstop softtabstop expandtab Cc:
Blocked By: Blocking:
Branch state: no branch Votes for changeset:

Description

Vim have useful feature, to set indentation related configuration per-file. It's done by adding a comment to the source file (usually at the end), for example:

/* vim: set tabstop=8 softtabstop=4 shiftwidth=4 noexpandtab: */

The above config means in mc:

  • Fake half tabs enabled
  • Fill tabs with spaces disabled
  • Tab spacing 8

I think having such feature in mc would be a nice step forward. I also think it should use the same namespace as vim, despite being totally distinct project.

Attachments

mcedit-vim-modeline-1.patch (9.8 KB) - added by twasilczyk 11 years ago.
Added vim's modeline support - initial implementation
mcedit-vim-modeline-2.patch (18.8 KB) - added by twasilczyk 11 years ago.
Added vim's modeline support - with "tabstop" mapped to tab spacing
mcedit-vim-modeline-3.patch (18.8 KB) - added by twasilczyk 11 years ago.
Small bugfix (backspace at line beginning created spaces)
mcedit-vim-modeline-4.patch (19.4 KB) - added by twasilczyk 11 years ago.
Various comment types supported

Change History

Changed 11 years ago by twasilczyk

Added vim's modeline support - initial implementation

comment:1 follow-up: ↓ 2 Changed 11 years ago by twasilczyk

I did initial implementation for this, however, it needs some work:

  • mc_findinfile should be placed somewhere else (maybe vfs.h?) and maybe named somehow better
  • vim's tabstop parameter isn't mapped to mc's tab spacing (it's easy to implement, I'll do it later)
  • currently, only C comments are supported; we should discuss other comment types that should be supported (C++ //, Python's #, others?)
  • I guess there should be some max size limit, to not look for config in 1MB+ files
  • mc depends on glib (which version?) so the scan could take advantage of it (regexp?)
  • there should be a warning in config file, if the global settings are overriden by local ones
  • if using fake half tabs with no tab-to-space filling, there is a possibility to create "bad" indentations (<tab><4xspace><tab><tab><4xspace>) - they should be converted (when editing a specific indentation) to standard ones (<tab><tab><tab><4xspace>)
Version 0, edited 11 years ago by twasilczyk (next)

comment:2 in reply to: ↑ 1 ; follow-up: ↓ 3 Changed 11 years ago by andrew_b

Replying to twasilczyk:

I did initial implementation for this, however, it needs some work:

Thanks!

Some remarks:

  • this option should be optional
  • I guess there should be some max size limit, to not look for config in 1MB+ files
  • scanning modeline in editor buffer after (or even during) file load is better than scanning directly in file because we scan file only once. mcedit supports file of any size.
  • mc depends on glib (which version?) so the scan could take advantage of it (regexp?)
  • glib >= 2.12 is required, but mc already has own regexp-based search engine (see lib/search, lib/search.h)

comment:3 in reply to: ↑ 2 Changed 11 years ago by twasilczyk

Replying to andrew_b:
If we scan for modeline during file load, there will be no necessity to omit 1MB+ files, as it won't affect performance.

Changed 11 years ago by twasilczyk

Added vim's modeline support - with "tabstop" mapped to tab spacing

Changed 11 years ago by twasilczyk

Small bugfix (backspace at line beginning created spaces)

Changed 11 years ago by twasilczyk

Various comment types supported

comment:4 Changed 11 years ago by angel_il

so... scan_modeline try scan all file, potentially this could take a long time...
for example file size is 4gb, without '\n'

comment:5 Changed 11 years ago by twasilczyk

As far, as I understand, file is scanned anyway (for example, to find out the number of lines). Thus, adding another check into that loop won't affect performance that much.

Am I right?

comment:6 Changed 11 years ago by angel_il

i think, need scan first ~2000b

Last edited 11 years ago by angel_il (previous) (diff)

comment:7 Changed 11 years ago by ossi

maybe also the last - some files have the modeline at the bottom.

there is also an entirely different approach to the matter: http://kate-editor.org/2006/02/09/kateconfig-files/

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