Better name inference

spec/integrity_spec.lua

@@ -5,7 +5,7 @@ describe("tests related to CLI behaviour #unsafe", function()
       it("generates correct error message without arguments", function()
          local handler = io.popen("./spec/script 2>&1", "r")
          assert.equal(table.concat({
-            "Usage: test [-v] [-h] <input> [<command>] ...",
+            "Usage: ./spec/script [-v] [-h] <input> [<command>] ...",
             "",
             "Error: too few arguments",
             ""
@@ -16,7 +16,7 @@ describe("tests related to CLI behaviour #unsafe", function()
       it("generates correct error message with too many arguments", function()
          local handler = io.popen("./spec/script foo bar 2>&1", "r")
          assert.equal(table.concat({
-            "Usage: test [-v] [-h] <input> [<command>] ...",
+            "Usage: ./spec/script [-v] [-h] <input> [<command>] ...",
             "",
             "Error: unknown command 'bar'",
             ""
@@ -27,7 +27,7 @@ describe("tests related to CLI behaviour #unsafe", function()
       it("generates correct error message with unexpected argument", function()
          local handler = io.popen("./spec/script --verbose=true 2>&1", "r")
          assert.equal(table.concat({
-            "Usage: test [-v] [-h] <input> [<command>] ...",
+            "Usage: ./spec/script [-v] [-h] <input> [<command>] ...",
             "",
             "Error: option '--verbose' does not take arguments",
             ""
@@ -38,7 +38,7 @@ describe("tests related to CLI behaviour #unsafe", function()
       it("generates correct error message with unexpected option", function()
          local handler = io.popen("./spec/script -vq 2>&1", "r")
          assert.equal(table.concat({
-            "Usage: test [-v] [-h] <input> [<command>] ...",
+            "Usage: ./spec/script [-v] [-h] <input> [<command>] ...",
             "",
             "Error: unknown option '-q'",
             "Did you mean one of these: '-h' '-v'?",
@@ -50,7 +50,7 @@ describe("tests related to CLI behaviour #unsafe", function()
       it("generates correct error message and tip with unexpected command", function()
          local handler = io.popen("./spec/script foo nstall 2>&1", "r")
          assert.equal(table.concat({
-            "Usage: test [-v] [-h] <input> [<command>] ...",
+            "Usage: ./spec/script [-v] [-h] <input> [<command>] ...",
             "",
             "Error: unknown command 'nstall'",
             "Did you mean 'install'?",
@@ -62,7 +62,7 @@ describe("tests related to CLI behaviour #unsafe", function()
       it("generates correct error message without arguments in command", function()
          local handler = io.popen("./spec/script foo install 2>&1", "r")
          assert.equal(table.concat({
-            "Usage: test install [-f <server>] [-h] <rock> [<version>]",
+            "Usage: ./spec/script install [-f <server>] [-h] <rock> [<version>]",
             "",
             "Error: too few arguments",
             ""
@@ -73,7 +73,7 @@ describe("tests related to CLI behaviour #unsafe", function()
       it("generates correct error message and tip in command", function()
          local handler = io.popen("./spec/script foo install bar --form=there 2>&1", "r")
          assert.equal(table.concat({
-            "Usage: test install [-f <server>] [-h] <rock> [<version>]",
+            "Usage: ./spec/script install [-f <server>] [-h] <rock> [<version>]",
             "",
             "Error: unknown option '--form'",
             "Did you mean '--from'?",
@@ -87,7 +87,7 @@ describe("tests related to CLI behaviour #unsafe", function()
       it("generates correct help message", function()
          local handler = io.popen("./spec/script --help 2>&1", "r")
          assert.equal(table.concat({
-            "Usage: test [-v] [-h] <input> [<command>] ...",
+            "Usage: ./spec/script [-v] [-h] <input> [<command>] ...",
             "",
             "A testing program. ",
             "",
@@ -108,7 +108,7 @@ describe("tests related to CLI behaviour #unsafe", function()
       it("generates correct help message for command", function()
          local handler = io.popen("./spec/script foo install --help 2>&1", "r")
          assert.equal(table.concat({
-            "Usage: test install [-f <server>] [-h] <rock> [<version>]",
+            "Usage: ./spec/script install [-f <server>] [-h] <rock> [<version>]",
             "",
             "Install a rock. ",
             "",

spec/script

@@ -1,7 +1,7 @@
 #!/usr/bin/env lua
 local Parser = require "argparse"
 
-local parser = Parser "test"
+local parser = Parser()
    :description "A testing program. "
    :require_command(false)
 
@@ -26,6 +26,8 @@ install:option "-f" "--from"
    :description "Fetch the rock from this server. "
    :target "server"
 
+local usage = parser:get_usage()
+local help = parser:get_help()
 local args = parser:parse()
 
 print(args.input)

src/argparse.lua

@@ -27,7 +27,7 @@ do -- Create classes with setters
                   table.insert(self._aliases, name_or_options)
                end
 
-               if not self._name then
+               if not self._aliases or not self._name then
                   self._name = name_or_options
                end
             elseif type(name_or_options) == "table" then
@@ -576,13 +576,6 @@ end
 
 function Parser:_parse(args, errhandler)
    args = args or arg
-   local noname
-
-   if not self._name then
-      noname = true
-      self._name = args[0]
-   end
-
    local parser
    local charset
    local options = {}
@@ -889,10 +882,6 @@ function Parser:_parse(args, errhandler)
       end
    end
 
-   if noname then
-      self._name = nil
-   end
-
    return result
 end
 
@@ -927,5 +916,5 @@ function Parser:pparse(args)
 end
 
 return function(...)
-   return Parser():add_help(true)(...)
+   return Parser(arg[0]):add_help(true)(...)
 end