Added lfs.dir_foreach() for allowing Find in Files to have a filter.

Also moved snapopen module into core as io.snapopen().

1 files changed, 97 insertions, 0 deletions

diff --git a/core/lfs_ext.lua b/core/lfs_ext.lua
new file mode 100644
index 00000000..d79800a4
--- /dev/null
+++ b/core/lfs_ext.lua
@@ -0,0 +1,97 @@
+-- Copyright 2007-2013 Mitchell mitchell.att.foicica.com. See LICENSE.
+
+--[[ This comment is for LuaDoc.
+---
+-- Extends the `lfs` library to find files in directories.
+module('lfs')]]
+
+---
+-- Filter table containing common binary file extensions and version control
+-- folders to exclude when iterating over files and directories using
+-- `dir_foreach` when its `exclude_FILTER` argument is `false`.
+-- @see dir_foreach
+-- @class table
+-- @name FILTER
+lfs.FILTER = {
+  extensions = {
+    'a', 'bmp', 'bz2', 'class', 'dll', 'exe', 'gif', 'gz', 'jar', 'jpeg', 'jpg',
+    'o', 'png', 'so', 'tar', 'tgz', 'tif', 'tiff', 'zip'
+  },
+  folders = {'%.bzr$', '%.git$', '%.hg$', '%.svn$', 'CVS$'}
+}
+
+-- Determines whether or not the given file matches the given filter.
+-- @param file The filename.
+-- @param filter The filter table.
+-- @return boolean `true` or `false`.
+local function exclude(file, filter)
+  if not filter then return false end
+  local ext = filter.extensions
+  if ext and ext[file:match('[^%.]+$')] then return true end
+  for i = 1, #filter do
+    local patt = filter[i]
+    if patt:sub(1, 1) ~= '!' then
+      if file:find(patt) then return true end
+    else
+      if not file:find(patt:sub(2)) then return true end
+    end
+  end
+  return false
+end
+
+---
+-- Iterates over all files and sub-directories in the UTF-8-encoded directory
+-- *utf8_dir*, calling function *f* on each file found.
+-- Files *f* is called on do not match any pattern in string or table *filter*,
+-- and, unless *exclude_FILTER* is `true`, `FILTER` as well. A filter table
+-- contains Lua patterns that match filenames to exclude, with patterns matching
+-- folders to exclude listed in a `folders` sub-table. Patterns starting with
+-- '!' exclude files and folders that do not match the pattern that follows. Use
+-- a table of raw file extensions assigned to an `extensions` key for fast
+-- filtering by extension. All strings must be encoded in `_G._CHARSET`, not
+-- UTF-8.
+-- @param utf8_dir A UTF-8-encoded directory path to iterate over.
+-- @param f Function to call with each full file path found. File paths are
+--   **not** encoded in UTF-8, but in `_G._CHARSET`. If *f* returns `false`
+--   explicitly, iteration ceases.
+-- @param filter Optional filter for files and folders to exclude.
+-- @param exclude_FILTER Optional flag indicating whether or not to exclude the
+--   default filter `FILTER` in the search. If `false`, adds `FILTER` to
+--   *filter*.
+--   The default value is `false` to include the default filter.
+-- @param recursing Utility flag indicating whether or not this function has
+--   been recursively called. This flag is used and set internally, and should
+--   not be set otherwise.
+-- @see FILTER
+-- @name dir_foreach
+function lfs.dir_foreach(utf8_dir, f, filter, exclude_FILTER, recursing)
+  if not recursing then
+    -- Convert filter to a table from nil or string arguments.
+    if not filter then filter = {} end
+    if type(filter) == 'string' then filter = {filter} end
+    -- Add FILTER to filter unless specified otherwise.
+    if not exclude_FILTER then
+      for k, v in pairs(lfs.FILTER) do
+        if not filter[k] then filter[k] = {} end
+        local filter_k = filter[k]
+        for i = 1, #v do filter_k[#filter_k + 1] = v[i] end
+      end
+    end
+    -- Create file extension filter hash table for quick lookups.
+    local ext = filter.extensions
+    if ext then for i = 1, #ext do ext[ext[i]] = true end end
+  end
+  local dir = utf8_dir:iconv(_CHARSET, 'UTF-8')
+  local lfs_attributes = lfs.attributes
+  for file in lfs.dir(dir) do
+    if not file:find('^%.%.?$') then -- ignore . and ..
+      file = dir..(not WIN32 and '/' or '\\')..file
+      local type = lfs_attributes(file, 'mode')
+      if type == 'directory' and not exclude(file, filter.folders) then
+        lfs.dir_foreach(file, f, filter, nil, true)
+      elseif type == 'file' and not exclude(file, filter) then
+        if f(file) == false then return end
+      end
+    end
+  end
+end