Use argparse for command line argument parsing

Supports main options and init and lint commands

7 files changed, 209 insertions, 432 deletions

diff --git a/src/bin/luarocks b/src/bin/luarocks
index d982530c..f277b348 100755
--- a/src/bin/luarocks
+++ b/src/bin/luarocks
@@ -33,4 +33,4 @@ local commands = {
    test = "luarocks.cmd.test",
 }
 
-cmd.run_command(description, commands, "luarocks.cmd.external", ...)
+cmd.run_command("luarocks", description, commands, "luarocks.cmd.external", ...)
diff --git a/src/bin/luarocks-admin b/src/bin/luarocks-admin
index 71e17b55..ddbe0f48 100755
--- a/src/bin/luarocks-admin
+++ b/src/bin/luarocks-admin
@@ -16,4 +16,4 @@ local commands = {
    refresh_cache = "luarocks.admin.cmd.refresh_cache",
 }
 
-cmd.run_command(description, commands, "luarocks.admin.cmd.external", ...)
+cmd.run_command("luarocks-admin", description, commands, "luarocks.admin.cmd.external", ...)
diff --git a/src/luarocks/cmd.lua b/src/luarocks/cmd.lua
index 1ead6c4b..23ca023a 100644
--- a/src/luarocks/cmd.lua
+++ b/src/luarocks/cmd.lua
@@ -2,16 +2,14 @@
 --- Functions for command-line scripts.
 local cmd = {}
 
-local unpack = unpack or table.unpack
-
 local loader = require("luarocks.loader")
 local util = require("luarocks.util")
 local path = require("luarocks.path")
-local deps = require("luarocks.deps")
 local cfg = require("luarocks.core.cfg")
 local dir = require("luarocks.dir")
 local fun = require("luarocks.fun")
 local fs = require("luarocks.fs")
+local argparse = require("argparse")
 
 local hc_ok, hardcoded = pcall(require, "luarocks.core.hardcoded")
 if not hc_ok then
@@ -91,8 +89,8 @@ do
          else
             replace_tree(flags, cfg.home_tree)
          end
-      elseif flags["project-tree"] then
-         local tree = flags["project-tree"]
+      elseif flags["project_tree"] then
+         local tree = flags["project_tree"]
          table.insert(cfg.rocks_trees, 1, { name = "project", root = tree } )
          loader.load_rocks_trees()
          path.use_tree(tree)
@@ -131,14 +129,14 @@ local function process_server_flags(flags)
       cfg.rocks_servers = fun.concat(dev_servers, cfg.rocks_servers)
    end
 
-   if flags["only-server"] then
+   if flags["only_server"] then
       if flags["dev"] then
          return nil, "--only-server cannot be used with --dev"
       end
       if flags["server"] then
          return nil, "--only-server cannot be used with --server"
       end
-      cfg.rocks_servers = { flags["only-server"] }
+      cfg.rocks_servers = { flags["only_server"] }
    end
 
    return true
@@ -231,12 +229,12 @@ do
       end
    
       local function detect_lua_via_flags(flags, project_dir)
-         local lua_version = flags["lua-version"]
+         local lua_version = flags["lua_version"]
                              or find_default_lua_version(flags, project_dir)
                              or (project_dir and find_version_from_config(project_dir))
       
-         if flags["lua-dir"] then
-            local detected, err = util.find_lua(flags["lua-dir"], lua_version)
+         if flags["lua_dir"] then
+            local detected, err = util.find_lua(flags["lua_dir"], lua_version)
             if not detected then
                die(err)
             end
@@ -265,13 +263,13 @@ do
       end
       
       detect_config_via_flags = function(flags)
-         local project_dir, given = find_project_dir(flags["project-tree"])
+         local project_dir, given = find_project_dir(flags["project_tree"])
          local detected = detect_lua_via_flags(flags, project_dir)
-         if flags["lua-version"] then
-            detected.given_lua_version = flags["lua-version"]
+         if flags["lua_version"] then
+            detected.given_lua_version = flags["lua_version"]
          end
-         if flags["lua-dir"] then
-            detected.given_lua_dir = flags["lua-dir"]
+         if flags["lua_dir"] then
+            detected.given_lua_dir = flags["lua_dir"]
          end
          if given then
             detected.given_project_dir = project_dir
@@ -306,6 +304,103 @@ do
    end
 end
 
+local function get_status(status)
+   return status and "ok" or "not found"
+end
+
+local function get_config_text()
+   local buf = "Configuration:\n   Lua version: "..cfg.lua_version.."\n"
+   if cfg.luajit_version then
+      buf = buf.."   LuaJIT version: "..cfg.luajit_version.."\n"
+   end
+   buf = buf.."\n   Configuration files:\n"
+   local conf = cfg.config_files
+   buf = buf.."      System  : "..fs.absolute_name(conf.system.file).." ("..get_status(conf.system.found)..")\n"
+   if conf.user.file then
+      buf = buf.."      User    : "..fs.absolute_name(conf.user.file).." ("..get_status(conf.user.found)..")\n"
+   else
+      buf = buf.."      User    : disabled in this LuaRocks installation.\n"
+   end
+   if conf.project then
+      buf = buf.."      Project : "..fs.absolute_name(conf.project.file).." ("..get_status(conf.project.found)..")\n"
+   end
+   buf = buf.."\n   Rocks trees in use: \n"
+   for _, tree in ipairs(cfg.rocks_trees) do
+      if type(tree) == "string" then
+         buf = buf.."      "..fs.absolute_name(tree)
+      else
+         local name = tree.name and " (\""..tree.name.."\")" or ""
+         buf = buf.."      "..fs.absolute_name(tree.root)..name
+      end
+   end
+
+   return buf.."\n"
+end
+
+local function get_parser(program_name, description, cmd_modules)
+   local epilog = [[
+Variables:
+   Variables from the "variables" table of the configuration file can be
+   overridden with VAR=VALUE assignments.
+
+]]..get_config_text()
+
+   local parser = argparse(
+      program_name, "LuaRocks "..cfg.program_version..", the Lua package manager\n\n"..
+      program.." - "..description, epilog)
+      :help_max_width(80)
+      :add_help("--help")
+      :add_help_command({add_help = false})
+      :command_target("command")
+      :require_command(false)
+
+   parser:flag("--version", "Show version info and exit.")
+      :action(function()
+         util.printout(program.." "..cfg.program_version)
+         util.printout(description)
+         util.printout()
+         os.exit(cmd.errorcodes.OK)
+      end)
+   parser:flag("--dev", "Enable the sub-repositories in rocks servers for "..
+      "rockspecs of in-development versions.")
+   parser:option("--server", "Fetch rocks/rockspecs from this server "..
+      "(takes priority over config file).")
+   parser:option("--only-server", "Fetch rocks/rockspecs from this server only "..
+      "(overrides any entries in the config file).")
+      :argname("<server>")
+   parser:option("--only-sources", "Restrict downloads to paths matching the given URL.")
+      :argname("<url>")
+   parser:option("--lua-dir", "Which Lua installation to use.")
+      :argname("<prefix>")
+   parser:option("--lua-version", "Which Lua version to use.")
+      :argname("<ver>")
+   parser:option("--tree", "Which tree to operate on.")
+   parser:option("--project-tree"):hidden(true)  -- TODO: Description?
+   parser:flag("--local", "Use the tree in the user's home directory.\n"..
+      "To enable it, see '"..program.." help path'.")
+   parser:flag("--global", "Use the system tree when `local_by_default` is `true`.")
+   parser:flag("--verbose", "Display verbose output of commands executed.")
+   parser:option("--timeout", "Timeout on network operations, in seconds.\n"..
+      "0 means no timeout (wait forever). Default is "..
+      tostring(cfg.connection_timeout)..".")
+      :argname("<seconds>")
+      :convert(tonumber)
+
+   -- Compatibility for old names of some options
+   parser:option("--to"):target("tree"):hidden(true)
+   parser:option("--from"):target("server"):hidden(true)
+   parser:option("--only-from"):target("only_server"):hidden(true)
+   parser:option("--only-sources-from"):target("only_sources"):hidden(true)
+
+   for _, module in util.sortedpairs(cmd_modules) do
+      if module.add_to_parser then -- TODO: Remove this check.
+         module.add_to_parser(parser)
+      end
+   end
+
+   return parser
+end
+
 --- Main command-line processor.
 -- Parses input arguments and calls the appropriate driver function
 -- to execute the action requested on the command-line, forwarding
@@ -314,11 +409,24 @@ end
 -- @param commands table: contains the loaded modules representing commands.
 -- @param external_namespace string: where to look for external commands.
 -- @param ... string: Arguments given on the command-line.
-function cmd.run_command(description, commands, external_namespace, ...)
+function cmd.run_command(program_name, description, commands, external_namespace, ...)
 
    check_popen()
 
-   local function process_arguments(...)
+   fs.init()
+
+   for _, module_name in ipairs(fs.modules(external_namespace)) do
+      if not commands[module_name] then
+         commands[module_name] = external_namespace.."."..module_name
+      end
+   end
+
+   local cmd_modules = {}
+   for name, module in pairs(commands) do
+      cmd_modules[name] = require(module)
+   end
+
+   local function process_cmdline_vars(...)
       local args = {...}
       local cmdline_vars = {}
       local last = #args
@@ -340,69 +448,38 @@ function cmd.run_command(description, commands, external_namespace, ...)
             end
          end
       end
-      local nonflags = { util.parse_flags(unpack(args)) }
-      local flags = table.remove(nonflags, 1)
-      if flags.ERROR then
-         die(flags.ERROR.." See --help.")
-      end
 
-      -- Compatibility for old names of some flags
-      if flags["to"] then flags["tree"] = flags["to"] end
-      if flags["from"] then flags["server"] = flags["from"] end
-      if flags["nodeps"] then flags["deps-mode"] = "none" end
-      if flags["only-from"] then flags["only-server"] = flags["only-from"] end
-      if flags["only-sources-from"] then flags["only-sources"] = flags["only-sources-from"] end
-
-      return flags, nonflags, cmdline_vars
+      return args, cmdline_vars
    end
 
-   local flags, nonflags, cmdline_vars = process_arguments(...)
+   local args, cmdline_vars = process_cmdline_vars(...)
+   local parser = get_parser(program_name, description, cmd_modules)
+   args = parser:parse(args)
 
-   if flags["timeout"] then   -- setting it in the config file will kick-in earlier in the process
-      local timeout = tonumber(flags["timeout"])
-      if timeout then
-         cfg.connection_timeout = timeout
-      else
-         die "Argument error: --timeout expects a numeric argument."
-      end
+   if not args.command then
+      util.printout(parser:get_help())
+      os.exit(cmd.errorcodes.OK)
    end
 
-   local command
-   if flags["help"] or #nonflags == 0 then
-      command = "help"
-   else
-      command = table.remove(nonflags, 1)
+   if args.timeout then -- setting it in the config file will kick-in earlier in the process
+      cfg.connection_timeout = args.timeout
    end
-   command = command:gsub("-", "_")
 
-   if command == "config" then
-      if nonflags[1] == "lua_version" and nonflags[2] then
-         flags["lua-version"] = nonflags[2]
-      elseif nonflags[1] == "lua_dir" and nonflags[2] then
-         flags["lua-dir"] = nonflags[2]
+   if args.command == "config" then
+      if args.key == "lua_version" and args.value then
+         args.lua_version = args.value
+      elseif args.key == "lua_dir" and args.value then
+         args.lua_dir = args.value
       end
    end
-
-   if flags["deps-mode"] and not deps.check_deps_mode_flag(flags["deps-mode"]) then
-      die("Invalid entry for --deps-mode.")
-   end
    
    -----------------------------------------------------------------------------
-   local lua_found, err = init_config(flags)
+   local lua_found, err = init_config(args)
    if err then
       die(err)
    end
    -----------------------------------------------------------------------------
 
-   if flags["version"] then
-      util.printout(program.." "..cfg.program_version)
-      util.printout(description)
-      util.printout()
-      os.exit(cmd.errorcodes.OK)
-   end
-
-   fs.init()
-
    -- if the Lua interpreter wasn't explicitly found before cfg.init,
    -- try again now.
    if not lua_found then
@@ -423,13 +500,7 @@ function cmd.run_command(description, commands, external_namespace, ...)
       cfg.project_dir = fs.absolute_name(cfg.project_dir)
    end
 
-   for _, module_name in ipairs(fs.modules(external_namespace)) do
-      if not commands[module_name] then
-         commands[module_name] = external_namespace.."."..module_name
-      end
-   end
-
-   if flags["verbose"] then
+   if args.verbose then
       cfg.verbose = true
       fs.verbose()
    end
@@ -438,24 +509,22 @@ function cmd.run_command(description, commands, external_namespace, ...)
       die("Current directory does not exist. Please run LuaRocks from an existing directory.")
    end
 
-   ok, err = process_tree_flags(flags, cfg.project_dir)
+   local ok, err = process_tree_flags(args, cfg.project_dir)
    if not ok then
       die(err)
    end
 
-   ok, err = process_server_flags(flags)
+   ok, err = process_server_flags(args)
    if not ok then
       die(err)
    end
 
-   if flags["only-sources"] then
-      cfg.only_sources_from = flags["only-sources"]
+   if args.only_sources then
+      cfg.only_sources_from = args.only_sources
    end
 
-   if command ~= "help" then
-      for k, v in pairs(cmdline_vars) do
-         cfg.variables[k] = v
-      end
+   for k, v in pairs(cmdline_vars) do
+      cfg.variables[k] = v
    end
 
    -- if running as superuser, use system cache dir
@@ -463,22 +532,15 @@ function cmd.run_command(description, commands, external_namespace, ...)
       cfg.local_cache = dir.path(fs.system_cache_dir(), "luarocks")
    end
 
-   if commands[command] then
-      local cmd_mod = require(commands[command])
-      local call_ok, ok, err, exitcode = xpcall(function()
-         if command == "help" then
-            return cmd_mod.command(description, commands, unpack(nonflags))
-         else
-            return cmd_mod.command(flags, unpack(nonflags))
-         end
-      end, error_handler)
-      if not call_ok then
-         die(ok, cmd.errorcodes.CRASH)
-      elseif not ok then
-         die(err, exitcode)
-      end
-   else
-      die("Unknown command: "..command)
+   local cmd_mod = cmd_modules[args.command]
+   local call_ok, ok, err, exitcode = xpcall(function()
+      return cmd_mod.command(args)
+   end, error_handler)
+
+   if not call_ok then
+      die(ok, cmd.errorcodes.CRASH)
+   elseif not ok then
+      die(err, exitcode)
    end
    util.run_scheduled_functions()
 end
diff --git a/src/luarocks/cmd/help.lua b/src/luarocks/cmd/help.lua
deleted file mode 100644
index b3d937e1..00000000
--- a/src/luarocks/cmd/help.lua
+++ /dev/null
@@ -1,139 +0,0 @@
-
---- Module implementing the LuaRocks "help" command.
--- This is a generic help display module, which
--- uses a global table called "commands" to find commands
--- to show help for; each command should be represented by a
--- table containing "help" and "help_summary" fields.
-local help = {}
-
-local util = require("luarocks.util")
-local cfg = require("luarocks.core.cfg")
-local dir = require("luarocks.dir")
-local fs = require("luarocks.fs")
-
-local program = util.this_program("luarocks")
-
-help.help_summary = "Help on commands. Type '"..program.." help <command>' for more."
-
-help.help_arguments = "[<command>]"
-help.help = [[
-<command> is the command to show help for.
-]]
-
-local function print_banner()
-   util.printout("\nLuaRocks "..cfg.program_version..", the Lua package manager")
-end
-
-local function print_section(section)
-   util.printout("\n"..section)
-end
-
-local function get_status(status)
-   if status then
-      return "ok"
-   else
-      return "not found"
-   end
-end
-
---- Driver function for the "help" command.
--- @param command string or nil: command to show help for; if not
--- given, help summaries for all commands are shown.
--- @return boolean or (nil, string): true if there were no errors
--- or nil and an error message if an invalid command was requested.
-function help.command(description, commands, command)
-   assert(type(description) == "string")
-   assert(type(commands) == "table")
-
-   if not command then
-      print_banner()
-      print_section("NAME")
-      util.printout("\t"..program..[[ - ]]..description)
-      print_section("SYNOPSIS")
-      util.printout("\t"..program..[[ [<flags...>] [VAR=VALUE]... <command> [<argument>] ]])
-      print_section("GENERAL OPTIONS")
-      util.printout([[
-        These apply to all commands, as appropriate:
-
-        --dev                  Enable the sub-repositories in rocks servers
-                               for rockspecs of in-development versions
-        --server=<server>      Fetch rocks/rockspecs from this server
-                               (takes priority over config file)
-        --only-server=<server> Fetch rocks/rockspecs from this server only
-                               (overrides any entries in the config file)
-        --only-sources=<url>   Restrict downloads to paths matching the
-                               given URL.
-        --lua-dir=<prefix>     Which Lua installation to use.
-        --lua-version=<ver>    Which Lua version to use.
-        --tree=<tree>          Which tree to operate on.
-        --local                Use the tree in the user's home directory.
-                               To enable it, see ']]..program..[[ help path'.
-        --global               Use the system tree when `local_by_default` is `true`.
-        --verbose              Display verbose output of commands executed.
-        --timeout=<seconds>    Timeout on network operations, in seconds.
-                               0 means no timeout (wait forever).
-                               Default is ]]..tostring(cfg.connection_timeout)..[[.]])
-      print_section("VARIABLES")
-      util.printout([[
-        Variables from the "variables" table of the configuration file
-        can be overridden with VAR=VALUE assignments.]])
-      print_section("COMMANDS")
-      for name, modname in util.sortedpairs(commands) do
-         local cmd = require(modname)
-         util.printout("", name)
-         util.printout("\t", cmd.help_summary)
-      end
-      print_section("CONFIGURATION")
-      util.printout("\tLua version: " .. cfg.lua_version)
-      local ljv = util.get_luajit_version()
-      if ljv then
-         util.printout("\tLuaJIT version: " .. ljv)
-      end
-      util.printout()
-      util.printout("\tConfiguration files:")
-      local conf = cfg.config_files
-      util.printout("\t\tSystem  : ".. fs.absolute_name(conf.system.file) .. " (" .. get_status(conf.system.found) ..")")
-      if conf.user.file then
-         util.printout("\t\tUser    : ".. fs.absolute_name(conf.user.file) .. " (" .. get_status(conf.user.found) ..")")
-      else
-         util.printout("\t\tUser    : disabled in this LuaRocks installation.")
-      end
-      if conf.project then
-         util.printout("\t\tProject : ".. fs.absolute_name(conf.project.file) .. " (" .. get_status(conf.project.found) ..")")
-      end
-      util.printout()
-      util.printout("\tRocks trees in use: ")
-      for _, tree in ipairs(cfg.rocks_trees) do
-         if type(tree) == "string" then
-            util.printout("\t\t"..fs.absolute_name(tree))
-         else
-            local name = tree.name and " (\""..tree.name.."\")" or ""
-            util.printout("\t\t"..fs.absolute_name(tree.root)..name)
-         end
-      end
-      util.printout()
-   else
-      command = command:gsub("-", "_")
-      local cmd = commands[command] and require(commands[command])
-      if cmd then
-         local arguments = cmd.help_arguments or "<argument>"
-         print_banner()
-         print_section("NAME")
-         util.printout("\t"..program.." "..command.." - "..cmd.help_summary)
-         print_section("SYNOPSIS")
-         util.printout("\t"..program.." "..command.." "..arguments)
-         print_section("DESCRIPTION")
-         util.printout("",(cmd.help:gsub("\n","\n\t"):gsub("\n\t$","")))
-         print_section("SEE ALSO")
-         if cmd.help_see_also then
-            util.printout(cmd.help_see_also)
-         end
-         util.printout("","'"..program.." help' for general options and configuration.\n")
-      else
-         return nil, "Unknown command: "..command
-      end
-   end
-   return true
-end
-
-return help
diff --git a/src/luarocks/cmd/init.lua b/src/luarocks/cmd/init.lua
index 60aa4f82..fc14baf6 100644
--- a/src/luarocks/cmd/init.lua
+++ b/src/luarocks/cmd/init.lua
@@ -10,27 +10,30 @@ local util = require("luarocks.util")
 local persist = require("luarocks.persist")
 local write_rockspec = require("luarocks.cmd.write_rockspec")
 
-init.help_summary = "Initialize a directory for a Lua project using LuaRocks."
-init.help_arguments = "[<name> [<version>]]"
-init.help = [[
-<name> is the project name.
-<version> is an optional project version.
-
---reset                  Delete .luarocks/config-5.x.lua and ./lua
-                         and generate new ones.
-
-Options for specifying rockspec data:
-
---license="<string>"     A license string, such as "MIT/X11" or "GNU GPL v3".
---summary="<txt>"        A short one-line description summary.
---detailed="<txt>"       A longer description string.
---homepage=<url>         Project homepage.
---lua-versions=<ver>     Supported Lua versions. Accepted values are "5.1", "5.2",
-                         "5.3", "5.1,5.2", "5.2,5.3", or "5.1,5.2,5.3".
---rockspec-format=<ver>  Rockspec format version, such as "1.0" or "1.1".
---lib=<lib>[,<lib>]      A comma-separated list of libraries that C files need to
-                         link to.
-]]
+function init.add_to_parser(parser)
+   local cmd = parser:command("init", "Initialize a directory for a Lua project using LuaRocks.", util.see_also())
+      :add_help(false)
+
+   cmd:argument("name", "The project name."):args("?")
+   cmd:argument("version", "An optional project version."):args("?")
+   cmd:flag("--reset", "Delete .luarocks/config-5.x.lua and ./lua and generate new ones.")
+
+   cmd:group("Options for specifying rockspec data",
+      cmd:option("--license", 'A license string, such as "MIT/X11" or "GNU GPL v3".')
+         :argname("<string>"),
+      cmd:option("--summary", "A short one-line description summary.")
+         :argname("<txt>"),
+      cmd:option("--detailed", "A longer description string.")
+         :argname("<txt>"),
+      cmd:option("--homepage", "Project homepage.")
+         :argname("<url>"),
+      cmd:option("--lua-versions", "Supported Lua versions. Accepted values are "..
+         '"5.1", "5.2", "5.3", "5.1,5.2", "5.2,5.3", or "5.1,5.2,5.3".'),
+      cmd:option("--rockspec-format", 'Rockspec format version, such as "1.0" or "1.1".')
+         :argname("<ver>"),
+      cmd:option("--lib", "A comma-separated list of libraries that C files need to link to.")
+         :argname("<libs>"))
+end
 
 local function write_gitignore(entries)
    local gitignore = ""
@@ -53,10 +56,11 @@ end
 
 --- Driver function for "init" command.
 -- @return boolean: True if succeeded, nil on errors.
-function init.command(flags, name, version)
+function init.command(args)
 
    local pwd = fs.current_dir()
 
+   local name = args.name
    if not name then
       name = dir.base_name(pwd)
       if name == "/" then
@@ -84,7 +88,7 @@ function init.command(flags, name, version)
    end
 
    if not has_rockspec then
-      local ok, err = write_rockspec.command(flags, name, version or "dev", pwd)
+      local ok, err = write_rockspec.command(args, name, args.version or "dev", pwd)
       if not ok then
          util.printerr(err)
       end
@@ -101,7 +105,7 @@ function init.command(flags, name, version)
    fs.make_dir(".luarocks")
    local config_file = ".luarocks/config-" .. cfg.lua_version .. ".lua"
 
-   if flags["reset"] then
+   if args.reset then
       fs.delete(lua_wrapper)
       fs.delete(config_file)
    end
diff --git a/src/luarocks/cmd/lint.lua b/src/luarocks/cmd/lint.lua
index c9ea45ea..433eed84 100644
--- a/src/luarocks/cmd/lint.lua
+++ b/src/luarocks/cmd/lint.lua
@@ -7,24 +7,22 @@ local util = require("luarocks.util")
 local download = require("luarocks.download")
 local fetch = require("luarocks.fetch")
 
-lint.help_summary = "Check syntax of a rockspec."
-lint.help_arguments = "<rockspec>"
-lint.help = [[
-This is a utility function that checks the syntax of a rockspec.
-
-It returns success or failure if the text of a rockspec is
-syntactically correct.
-]]
-
-function lint.command(flags, input)
-   if not input then
-      return nil, "Argument missing. "..util.see_help("lint")
-   end
-   
-   local filename = input
-   if not input:match(".rockspec$") then
+function lint.add_to_parser(parser)
+   local cmd = parser:command("lint", "Check syntax of a rockspec.\n\n"..
+      "Returns success if the text of the rockspec is syntactically correct, else failure.",
+      util.see_also())
+      :summary("Check syntax of a rockspec.")
+      :add_help(false)
+
+   cmd:argument("rockspec", "The rockspec to check.")
+end
+
+function lint.command(args)
+
+   local filename = args.rockspec
+   if not filename:match(".rockspec$") then
       local err
-      filename, err = download.download("rockspec", input:lower())
+      filename, err = download.download("rockspec", filename:lower())
       if not filename then
          return nil, err
       end
diff --git a/src/luarocks/util.lua b/src/luarocks/util.lua
index 6caba8cd..60cfb3d8 100644
--- a/src/luarocks/util.lua
+++ b/src/luarocks/util.lua
@@ -77,162 +77,6 @@ function util.matchquote(s)
    return (s:gsub("[?%-+*%[%].%%()$^]","%%%1"))
 end
 
---- List of supported arguments.
--- Arguments that take no parameters are marked with the boolean true.
--- Arguments that take a parameter are marked with a descriptive string.
--- Arguments that may take an empty string are described in quotes,
--- (as in the value for --detailed="<text>").
--- For all other string values, it means the parameter is mandatory.
-local supported_flags = {
-   ["all"] = true,
-   ["api-key"] = "<key>",
-   ["append"] = true,
-   ["arch"] = "<arch>",
-   ["bin"] = true,
-   ["binary"] = true,
-   ["branch"] = "<branch-name>",
-   ["build-deps"] = true,
-   ["debug"] = true,
-   ["deps"] = true,
-   ["deps-mode"] = "<mode>",
-   ["detailed"] = "\"<text>\"",
-   ["dev"] = true,
-   ["dir"] = "<path>",
-   ["force"] = true,
-   ["force-fast"] = true,
-   ["from"] = "<server>",
-   ["global"] = true,
-   ["help"] = true,
-   ["home"] = true,
-   ["homepage"] = "\"<url>\"",
-   ["index"] = true,
-   ["issues"] = true,
-   ["json"] = true,
-   ["keep"] = true,
-   ["labels"] = true,
-   ["lib"] = "<library>",
-   ["license"] = "\"<text>\"",
-   ["list"] = true,
-   ["local"] = true,
-   ["local-tree"] = true,
-   ["lr-bin"] = true,
-   ["lr-cpath"] = true,
-   ["lr-path"] = true,
-   ["lua-dir"] = "<path>",
-   ["lua-version"] = "<vers>",
-   ["lua-versions"] = "<versions>",
-   ["lua-ver"] = true,
-   ["lua-incdir"] = true,
-   ["lua-libdir"] = true,
-   ["modules"] = true,
-   ["mversion"] = true,
-   ["namespace"] = "<namespace>",
-   ["no-bin"] = true,
-   ["no-doc"] = true,
-   ["no-refresh"] = true,
-   ["nodeps"] = true,
-   ["old-versions"] = true,
-   ["only-deps"] = true,
-   ["only-from"] = "<server>",
-   ["only-server"] = "<server>",
-   ["only-sources"] = "<url>",
-   ["only-sources-from"] = "<url>",
-   ["outdated"] = true,
-   ["output"] = "<file>",
-   ["pack-binary-rock"] = true,
-   ["porcelain"] = true,
-   ["project-tree"] = "<tree>",
-   ["quick"] = true,
-   ["reset"] = true,
-   ["rock-dir"] = true,
-   ["rock-license"] = true,
-   ["rock-namespace"] = true,
-   ["rock-tree"] = true,
-   ["rock-trees"] = true,
-   ["rockspec"] = true,
-   ["rockspec-format"] = "<ver>",
-   ["scope"] = "<system|user|project>",
-   ["server"] = "<server>",
-   ["sign"] = true,
-   ["skip-pack"] = true,
-   ["source"] = true,
-   ["summary"] = "\"<text>\"",
-   ["system-config"] = true,
-   ["tag"] = "<tag>",
-   ["test-type"] = "<type>",
-   ["temp-key"] = "<key>",
-   ["timeout"] = "<seconds>",
-   ["to"] = "<path>",
-   ["tree"] = "<path>",
-   ["unset"] = true,
-   ["user-config"] = true,
-   ["verbose"] = true,
-   ["verify"] = true,
-   ["version"] = true,
-}
-
---- Extract flags from an arguments list.
--- Given string arguments, extract flag arguments into a flags set.
--- For example, given "foo", "--tux=beep", "--bla", "bar", "--baz",
--- it would return the following:
--- {["bla"] = true, ["tux"] = "beep", ["baz"] = true}, "foo", "bar".
-function util.parse_flags(...)
-   local args = {...}
-   local flags = {}
-   local i = 1
-   local out = {}
-   local state = "initial"
-   while i <= #args do
-      local flag = args[i]:match("^%-%-(.*)")
-      if state == "initial" and flag == "" then
-         state = "ignore_flags"
-      elseif state == "initial" and flag then
-         local var,val = flag:match("([a-z_%-]*)=(.*)")
-         if val then
-            local vartype = supported_flags[var]
-            if type(vartype) == "string" then
-               if val == "" and vartype:sub(1,1) ~= '"' then
-                  return { ERROR = "Invalid argument: parameter to flag --"..var.."="..vartype.." cannot be empty." }
-               end
-               flags[var] = val
-            else
-               if vartype then
-                  return { ERROR = "Invalid argument: flag --"..var.." does not take an parameter." }
-               else
-                  return { ERROR = "Invalid argument: unknown flag --"..var.."." }
-               end
-            end
-         else
-            local var = flag
-            local vartype = supported_flags[var]
-            if type(vartype) == "string" then
-               i = i + 1
-               local val = args[i]
-               if not val then
-                  return { ERROR = "Invalid argument: flag --"..var.."="..vartype.." expects a parameter." }
-               end
-               if val:match("^%-%-.*") then
-                  return { ERROR = "Invalid argument: flag --"..var.."="..vartype.." expects a parameter (if you really want to pass "..val.." as an argument to --"..var..", use --"..var.."="..val..")." }
-               else
-                  if val == "" and vartype:sub(1,1) ~= '"' then
-                     return { ERROR = "Invalid argument: parameter to flag --"..var.."="..vartype.." cannot be empty." }
-                  end
-                  flags[var] = val
-               end
-            elseif vartype == true then
-               flags[var] = true
-            else
-               return { ERROR = "Invalid argument: unknown flag --"..var.."." }
-            end
-         end
-      elseif state == "ignore_flags" or (state == "initial" and not flag) then
-         table.insert(out, args[i])
-      end
-      i = i + 1
-   end
-   return flags, unpack(out)
-end
-
 local var_format_pattern = "%$%((%a[%a%d_]+)%)"
 
 -- Check if a set of needed variables are referenced
@@ -394,6 +238,14 @@ function util.see_help(command, program)
    return "See '"..util.this_program(program or "luarocks")..' help'..(command and " "..command or "").."'."
 end
 
+function util.see_also(text)
+   local see_also = "See also:\n"
+   if text then
+      see_also = see_also..text.."\n"
+   end
+   return see_also.."   '"..util.this_program("luarocks").." help' for general options and configuration."
+end
+
 function util.announce_install(rockspec)
    local cfg = require("luarocks.core.cfg")
    local path = require("luarocks.path")