Improved command line parsing

The first character after control character is now not required to be a letter

spec/help_spec.lua

@@ -23,12 +23,12 @@ describe("tests related to help message generation", function()
 
    it("uses custom help option", function()
       local parser = Parser "foo"
-         :add_help {aliases = {"\\?"}}
+         :add_help {name = "/?"}
       assert.equal(table.concat({
-         "Usage: foo [\\?]",
+         "Usage: foo [/?]",
          "",
          "Options: ",
-         "   \\?                    Show this help message and exit. "
+         "   /?                    Show this help message and exit. "
       }, "\r\n"), parser:prepare():get_help())
    end)
 

spec/options_spec.lua

@@ -16,6 +16,14 @@ describe("tests related to options", function()
          assert.same({server = "foo"}, args)
       end)
 
+      it("handles non-standard charset", function()
+         local parser = Parser()
+         parser:option "/s"
+         parser:flag "/?"
+         local args = parser:parse{"/s", "foo", "/?"}
+         assert.same({s = "foo", ["?"] = true}, args)
+      end)
+
       it("handles GNU-style long options", function()
          local parser = Parser()
          parser:option("-s", "--server")

src/argparse.lua

@@ -267,7 +267,11 @@ function Parser:prepare()
          end)
 
       if #self._help_option._aliases == 0 then
-         self._help_option "-h" "--help"
+         if self._help_option._name then
+            self._help_option._aliases[1] = self._help_option._name
+         else
+            self._help_option "-h" "--help"
+         end
       end
 
       if not self._help_option._description then
@@ -282,7 +286,7 @@ function Parser:prepare()
    end
 
    for _, command in ipairs(self._commands) do
-      command._target =command._target or command._name
+      command._target = command._target or command._name
       command._name = self._name .. " " .. command._name
    end
 
@@ -700,26 +704,11 @@ function Parser:_parse(args, errhandler)
             first = data:sub(1, 1)
             if charset[first] then
                if #data > 1 then
-                  if data:sub(2, 2):match "[a-zA-Z]" then
+                  plain = false
-                     plain = false
+                  if data:sub(2, 2) == first then
-
-                     for i = 2, #data do
-                        name = first .. data:sub(i, i)
-                        option = get_option(name)
-                        handle_option(name)
-
-                        if i ~= #data and option._minargs > 0 then
-                           handle_argument(data:sub(i+1))
-                           break
-                        end
-                     end
-                  elseif data:sub(2, 2) == first then
                      if #data == 2 then
-                        plain = false
                         handle_options = false
-                     elseif data:sub(3, 3):match "[a-zA-Z]" then
+                     else
-                        plain = false
-
                         local equal = data:find "="
                         if equal then
                            name = data:sub(1, equal-1)
@@ -733,6 +722,17 @@ function Parser:_parse(args, errhandler)
                            handle_option(data)
                         end
                      end
+                  else
+                     for i = 2, #data do
+                        name = first .. data:sub(i, i)
+                        option = get_option(name)
+                        handle_option(name)
+
+                        if i ~= #data and option._minargs > 0 then
+                           handle_argument(data:sub(i+1))
+                           break
+                        end
+                     end
                   end
                end
             end