url.lua: separate remove_dot_components() from absolute_path(); also use in _M.absolute() even when not merging

1 files changed, 34 insertions, 17 deletions

diff --git a/src/url.lua b/src/url.lua
index 29b6734..a354ab5 100644
--- a/src/url.lua
+++ b/src/url.lua
@@ -77,24 +77,19 @@ function _M.unescape(s)
 end
 
 -----------------------------------------------------------------------------
--- Builds a path from a base path and a relative path
+-- Removes '..' and '.' components appropriately from a path.
 -- Input
---   base_path
---   relative_path
+--   path
 -- Returns
---   corresponding absolute path
------------------------------------------------------------------------------
-local function absolute_path(base_path, relative_path)
-    if string.sub(relative_path, 1, 1) == "/" then return relative_path end
-    local path = string.gsub(base_path, "[^/]*$", "")
-    path = path .. relative_path
+--   dot-normalized path
+local function remove_dot_components(path)
     repeat
-      local was = path
-      path = path:gsub('/%./', '/')
+        local was = path
+        path = path:gsub('/%./', '/')
     until path == was
     repeat
-      local was = path
-      path = path:gsub('[^/]+/%.%./([^/]+)', '%1')
+        local was = path
+        path = path:gsub('[^/]+/%.%./([^/]+)', '%1')
     until path == was
     path = path:gsub('[^/]+/%.%./*$', '')
     path = path:gsub('/%.%.$', '/')
@@ -104,6 +99,23 @@ local function absolute_path(base_path, relative_path)
 end
 
 -----------------------------------------------------------------------------
+-- Builds a path from a base path and a relative path
+-- Input
+--   base_path
+--   relative_path
+-- Returns
+--   corresponding absolute path
+-----------------------------------------------------------------------------
+local function absolute_path(base_path, relative_path)
+    if string.sub(relative_path, 1, 1) == "/" then
+      return remove_dot_components(relative_path) end
+    base_path = base_path:gsub("[^/]*$", "")
+    local path = base_path .. relative_path
+    path = remove_dot_components(path)
+    return path
+end
+
+-----------------------------------------------------------------------------
 -- Parses a url and returns a table with all its parts according to RFC 2396
 -- The following grammar describes the names given to the URL parts
 -- <url> ::= <scheme>://<authority>/<path>;<params>?<query>#<fragment>
@@ -225,10 +237,14 @@ function _M.absolute(base_url, relative_url)
     else
         base_parsed = _M.parse(base_url)
     end
+    local result
     local relative_parsed = _M.parse(relative_url)
-    if not base_parsed then return relative_url
-    elseif not relative_parsed then return base_url
-    elseif relative_parsed.scheme then return relative_url
+    if not base_parsed then
+        result = relative_url
+    elseif not relative_parsed then
+        result = base_url
+    elseif relative_parsed.scheme then
+        result = relative_url
     else
         relative_parsed.scheme = base_parsed.scheme
         if not relative_parsed.authority then
@@ -246,8 +262,9 @@ function _M.absolute(base_url, relative_url)
                     relative_parsed.path)
             end
         end
-        return _M.build(relative_parsed)
+        result = _M.build(relative_parsed)
     end
+    return remove_dot_components(result)
 end
 
 -----------------------------------------------------------------------------