project.lua

-- The __common.project__ module tries to figure out the project root directory
-- for a given file. If you have a directory structure
-- like
--     code
--       project1
--         src
--           file1.lua
--       project2
--         src
-- the function __root__ returns *project1* for `file1.lua`
-- if `code` is part of the `common.project.DIRS` table.
-- If the project root is not found in `DIRS` the file's directory is returned.

module('_m.common.project', package.seeall)

-- ## Fields

-- This `DIRS` field can be overwritten or added to in your `init.lua` after
-- the _common_ module has been loaded, for example:
--     _m.common.project.DIRS = { _USERHOME..'/modules',
--                                '/home/username/code',
--                                '/home/username/projects' }
-- The default value contains Textadept's directory and the user's
-- modules directory.
DIRS = { _HOME, _USERHOME..'/modules' }

-- ## Commands

-- Match a file's path with project root directories and try to return the
-- project root.  If the project root is not found the file's directory
-- is returned.
function root()
  local filename = buffer.filename
  local project_root
  if filename then
    for i=1, #DIRS do
      project_root = filename:match('('..DIRS[i]..'[/\\][^/\\]+)[/\\].+')
      if project_root then
        break
      end
    end
  end
  return project_root or buffer.filename:match('(.+)[/\\]')
end