From 175776812e32e93ec9c85efb5576e4b10663aadf Mon Sep 17 00:00:00 2001
From: Myk Taylor <myk.taylor@gmail.com>
Date: Tue, 3 Nov 2020 16:19:50 -0800
Subject: [PATCH] implement a nice API wrapper for getopt

---
 library/lua/utils.lua | 49 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/library/lua/utils.lua b/library/lua/utils.lua
index 43dcdcd60..ee2cadd29 100644
--- a/library/lua/utils.lua
+++ b/library/lua/utils.lua
@@ -613,6 +613,55 @@ function processArgs(args, validArgs)
     return result
 end
 
+-- processes commandline options according to optionActions and returns all
+-- argument strings that are not options.
+--
+-- optionActions is a vector with elements in the following format:
+-- {shortOptionName, longOptionAlias, hasArg=boolean, handler=fn}
+-- shortOptionName and handler are required. If the option takes an argument,
+-- it will be passed to the handler function.
+-- longOptionAlias is optional.
+-- hasArgument defaults to false.
+--
+-- example usage:
+--
+-- local filename = nil
+-- local open_readonly = false
+-- local nonoptions = processArgs2(args, {
+--   {'r', handler=function() open_readonly = true end},
+--   {'f', 'filename', hasArg=true,
+--    handler=function(optarg) filename = optarg end}
+-- })
+--
+-- when args is {'first', '-f', 'fname', 'second'}
+-- then filename will be fname and nonoptions will contain {'first', 'second'}
+function processArgs2(args, optionActions)
+    local sh_opts, long_opts = '', {}
+    local handlers = {}
+    for _,optionAction in ipairs(optionActions) do
+        local sh_opt,long_opt = optionAction[1], optionAction[2]
+        if not sh_opt or type(sh_opt) ~= 'string' or #sh_opt ~= 1 then
+            qerror('optionAction missing option letter at index 1')
+        end
+        if not optionAction.handler then
+            qerror(string.format('handler missing for option "%s"', sh_opt))
+        end
+        sh_opts = sh_opts .. sh_opt
+        if optionAction.hasArg then sh_opts = sh_opts .. ':' end
+        handlers[sh_opt] = optionAction.handler
+        if long_opt then
+            long_opts[long_opt] = sh_opt
+            handlers[long_opt] = optionAction.handler
+        end
+    end
+    local getopt = require('3rdparty.alt_getopt').get_ordered_opts
+    local opts, optargs, nonoptions = getopt(args, sh_opts, long_opts)
+    for i,v in ipairs(opts) do
+        handlers[v](optargs[i])
+    end
+    return nonoptions
+end
+
 function fillTable(table1,table2)
     for k,v in pairs(table2) do
         table1[k] = v