Merge pull request #12 from wscherphof/#6-selectors

#6 selectors: :not() and [attribute="value"] working

ElementNode.lua

@@ -17,9 +17,7 @@ function ElementNode:new(nameortext, node, descend, openstart, openend)
     deepernodes = Set:new(),
     deeperelements = {}, deeperattributes = {}, deeperids = {}, deeperclasses = {}
   }
-  if nameortext == "container" then
-    instance.root = node
-  elseif not node then
+  if not node then
     instance.name = "root"
     instance.root = instance
     instance._text = nameortext
@@ -90,48 +88,67 @@ function ElementNode:close(closestart, closeend)
 end
 
 local function select(self, s)
-  if not s or type(s) ~= "string" then return {} end
-  local subjects = Set:new({self})
-  local resultset
-  local childrenonly
+  if not s or type(s) ~= "string" or s == "" then return Set:new() end
+
+  local function match(t, w)
+    local sets = {
+      [""]  = self.deeperelements,
+      ["["] = self.deeperattributes,
+      ["#"] = self.deeperids,
+      ["."] = self.deeperclasses
+    }
+    local v
+    if t == "[" then
+      w, v = string.match(w, 
+        "([^=]+)" .. -- w = 1 or more characters up to a possible "="
+        "=?" ..      -- an optional uncaptured "="
+        "(.*)"      -- v = anything following the "=", or else ""
+      )
+    end
+    local matched = sets[t][w]
+    if v and v ~= "" then
+      v = string.sub(v, 2, #v - 1) -- strip quotes
+      for node in pairs(matched) do
+        if node.attributes[w] ~= v then
+          matched:remove(node)
+        end
+      end
+    end
+    return matched
+  end
+
+  local subjects, resultset, childrenonly = Set:new({self})
   for part in string.gmatch(s, "%S+") do
     if part == ">" then childrenonly = true goto nextpart end
     resultset = Set:new()
     for subject in pairs(subjects) do
-      local init = subject.deepernodes
-      if childrenonly then init = Set:new(subject.nodes) childrenonly = false end
-      resultset = resultset + init
+      local star = subject.deepernodes
+      if childrenonly then star = Set:new(subject.nodes) end
+      childrenonly = false
+      resultset = resultset + star
     end
     if part == "*" then goto nextpart end
-    for t, w in string.gmatch(part, "([%[#%.]?)([^%[%]#%.]+)") do
-      if t == "" then resultset = resultset * self.deeperelements[w]
-      elseif t == "[" then resultset = resultset * self.deeperattributes[w]
-      elseif t == "#" then resultset = resultset * self.deeperids[w]
-      elseif t == "." then resultset = resultset * self.deeperclasses[w]
+    local excludes, filter = Set:new()
+    for t, w in string.gmatch(part,
+      "([:%[#.]?)" ..        -- t = an optional :, [, #, or .
+      "([^:%(%[#.%]%)]+)" .. -- w = 1 or more of anything not :, (, [, #, ., ], or )
+      "%]?%)?"               -- followed by an uncaptured optional ] and/or )
+    ) do
+      if t == ":" then filter = w goto nextw end
+      local matched = match(t, w)
+      if filter == "not" then
+        excludes = excludes + matched
+      else
+        resultset = resultset * matched
       end
+      filter = nil
+      ::nextw::
     end
+    resultset = resultset - excludes
     subjects = Set:new(resultset)
     ::nextpart::
   end
-  -- construct a container node for the resultset, so that we can :select() on it
-  local ret = ElementNode:new("container", self)
-  for node in pairs(resultset) do
-    table.insert(ret.nodes, node)
-    ret.deepernodes = ret.deepernodes + node.deepernodes
-    for listname,list in pairs({
-      deeperelements = node.deeperelements,
-      deeperattributes = node.deeperattributes,
-      deeperids = node.deeperids,
-      deeperclasses = node.deeperclasses
-    }) do
-      local target = ret[listname]
-      for k,set in pairs(list) do
-        -- Set.__add will create an empty Set if not target[k]
-        target[k] = target[k] + set
-      end
-    end
-  end
-  return ret
+  return resultset
 end
 
 function ElementNode:select(s) return select(self, s) end

htmlparser.lua

@@ -9,7 +9,11 @@ local function parse(text)
   local node, descend, tpos, opentags = root, true, 1, {}
   while true do
     local openstart, name
-    openstart, tpos, name = string.find(root._text, "<(%w+)[^>]*>", tpos)
+    openstart, tpos, name = string.find(root._text, 
+      "<" ..     -- an uncaptured starting "<"
+      "(%w+)" .. -- name = the first word, directly following the "<"
+      "[^>]*>",  -- include, but not capture everything up to the next ">"
+    tpos)
     if not name then break end
     local tag = ElementNode:new(name, node, descend, openstart, tpos)
     node = tag
@@ -17,12 +21,17 @@ local function parse(text)
     local tagst, apos = tag:gettext(), 1
     while true do
       local start, k, eq, quote, v
-      start, apos, k, eq, quote = string.find(tagst, "%s+([^%s=]+)(=?)(['\"]?)", apos)
-      if not k then break end
+      start, apos, k, eq, quote = string.find(tagst, 
+        "%s+" ..       -- some uncaptured space
+        "([^%s=]+)" .. -- k = an unspaced string up to an optional "="
+        "(=?)" ..      -- eq = the optiona; "=", else ""
+        "(['\"]?)",    -- quote = an optional "'" or '"' following the "=", or ""
+      apos)
+      if not k or k == "/>" then break end
       if eq == "" then
         v = ""
       else
-        local pattern = "=([^%s'\">]*)"
+        local pattern = "=([^%s>]*)"
         if quote ~= '' then
           pattern = quote .. "([^" .. quote .. "]*)" .. quote
         end

test.html

@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="en" test1='val1' test2="val='2'" test3='val="3"' test4="val = 4" test5=val5>
+<html lang="en" test1='val1' test2="val='2'" test3='val="3"' test4="val = 4" test5=val5 test6=val""6>
 <head>
   <meta charset="utf-8" />
   <link rel="stylesheet" href="test.css" />

test.lua

@@ -10,11 +10,8 @@ local root = htmlparser.parse(text)
 local function p(n)
   local space = string.rep("  ", n.level)
   local s = space .. n.name
-  for i,v in ipairs(n.nodes) do
-    s = s .. " nodes[" .. i .. "]=" .. v.name
-  end
   for k,v in pairs(n.attributes) do
-    s = s .. " " .. k .. "=[" .. v .. "]"
+    s = s .. " " .. k .. "=[[" .. v .. "]]"
   end
   print(s)
   for i,v in ipairs(n.nodes) do
@@ -26,11 +23,11 @@ p(root)
 local function select( s )
   print ""
   print("->", s)
-  local tags = root:select(s)
-  for i,t in ipairs(tags.nodes) do
-    print(t.name)
+  local sel = root:select(s)
+  for element in pairs(sel) do
+    print(element.name)
   end
-  print(# tags.nodes)
+  print(sel:len())
 end
 select("*")
 select("link")
@@ -51,10 +48,22 @@ select("ul > *")
 select("body [class]")
 select("body > [class]")
 
+select(".contacts span:not(.firstname)")
+select(":not(a)[href]")
+select("[itemscope]:not([itemprop])")
+
+select("link[rel='alternate']")
+select("[test2=\"val='2'\"]")
+select("[test5='val5']")
+select("[test6='val\"\"6']")
+select("[itemscope='']")
+select("[itemscope=]")
+select("[itemscope]")
+
 print("\nchapters")
 local sel, chapters = root("ol.chapters > li"), {}
-for _,v in ipairs(sel.nodes) do
-  table.insert(chapters, v:getcontent())
+for e in pairs(sel) do
+  table.insert(chapters, e:getcontent())
 end
 -- print
 for i,v in ipairs(chapters) do
@@ -62,11 +71,11 @@ for i,v in ipairs(chapters) do
 end
 
 print("\ncontacts")
-local sel, contacts = root("ul.contacts > li")("span[class]"), {}
-for _,v in ipairs(sel.nodes) do
-  local id = v.parent.parent.id -- li > a > span
+local sel, contacts = root("ul.contacts span[class]"), {}
+for e in pairs(sel) do
+  local id = e.parent.parent.id -- li > a > span
   contacts[id] = contacts[id] or {}
-  contacts[id][v.classes[1]] = v:getcontent()
+  contacts[id][e.classes[1]] = e:getcontent()
 end
 -- print
 for k,v in pairs(contacts) do
@@ -78,7 +87,7 @@ end
 
 print("\nmicrodata")
 local sel, scopes = root("[itemprop]"), {}
-for _,prop in ipairs(sel.nodes) do
+for prop in pairs(sel) do
   if prop.attributes["itemscope"] then goto nextprop end
   local descendantscopes, scope = {}, prop
   while true do
@@ -113,4 +122,4 @@ local function printscope(node, table, level)
 end
 for node,table in pairs(scopes) do
   printscope(node, table)
-end
+end