Merged dev to master.

data/core/common.lua

@@ -230,6 +230,12 @@ function common.basename(path)
 end
 
 
+-- can return nil if there is no directory part in the path
+function common.dirname(path)
+  return path:match("(.+)[\\/][^\\/]+$")
+end
+
+
 function common.home_encode(text)
   if HOME and string.find(text, HOME, 1, true) == 1 then
     local dir_pos = #HOME + 1
@@ -279,8 +285,27 @@ local function split_on_slash(s, sep_pattern)
 end
 
 
+function common.normalize_path(filename)
+  if PATHSEP == '\\' then
+    filename = filename:gsub('[/\\]', '\\')
+    local drive, rem = filename:match('^([a-zA-Z])(:.*)')
+    filename = drive and drive:upper() .. rem or filename
+  end
+  local parts = split_on_slash(filename, PATHSEP)
+  local accu = {}
+  for _, part in ipairs(parts) do
+    if part == '..' then
+      table.remove(accu)
+    elseif part ~= '.' then
+      table.insert(accu, part)
+    end
+  end
+  return table.concat(accu, PATHSEP)
+end
+
+
 function common.path_belongs_to(filename, path)
-  return filename and string.find(filename, path .. PATHSEP, 1, true) == 1
+  return string.find(filename, path .. PATHSEP, 1, true) == 1
 end