Allow unrecognized options to be ignored

src/parsing.jl

@@ -814,6 +814,19 @@ function parse1_optarg!(state::ParserState, settings::ArgParseSettings, f::ArgPa
     return
 end
 
+# Ignore arguments until next option is reached
+function skip_to_next_opt!(state::ParserState, settings::ArgParseSettings)
+    while !isempty(state.args_list)
+        if looks_like_an_option(state.args_list[1], settings)
+            break
+        end
+        popfirst!(state.args_list)
+    end
+    state.arg_consumed = true
+    state.command = nothing
+    return
+end
+
 # parse long opts
 function parse_long_opt!(state::ParserState, settings::ArgParseSettings)
     opt_name = state.token
@@ -838,7 +851,15 @@ function parse_long_opt!(state::ParserState, settings::ArgParseSettings)
         end
         exact_match && break
     end
-    nfound == 0 && argparse_error("unrecognized option --$opt_name")
+    if nfound == 0
+        if settings.ignore_unrecognized_opts
+            # Consume and skip any arguments after the option
+            skip_to_next_opt!(state, settings)
+            return
+        else
+            argparse_error("unrecognized option --$opt_name")
+        end
+    end
     nfound > 1 && argparse_error("long option --$opt_name is ambiguous ($nfound partial matches)")
 
     opt_name = fln
@@ -881,7 +902,15 @@ function parse_short_opt!(state::ParserState, settings::ArgParseSettings)
             found |= any(sn->sn==opt_name, f.short_opt_name)
             found && break
         end
-        found || argparse_error("unrecognized option -$opt_name")
+        if !found
+            if settings.ignore_unrecognized_opts
+                # Consume and skip any arguments after the option
+                skip_to_next_opt!(state, settings)
+                break
+            else
+                argparse_error("unrecognized option -$opt_name")
+            end
+        end
         if is_flag(f)
             parse1_flag!(state, settings, f, next_is_eq, "-"*opt_name)
         else

src/settings.jl

@@ -184,6 +184,10 @@ This is the list of general settings currently available:
   invoked from a script or in an interactive environment (e.g. REPL/IJulia). In non-interactive
   (script) mode, it calls `ArgParse.cmdline_handler`, which prints the error text and the usage
   screen on standard error and exits Julia with error code 1:
+* `ignore_unrecognized_opts` (default = `false`): if `true`, unrecognized options will be skipped.
+  `ignore_unrecognized_opts=true` cannot be used when there are any positional arguments, because it
+  is potentially ambiguous whether values after the unrecoginized option are supposed to be handled
+  by the option or by the positional argument.
 
   ```julia
   function cmdline_handler(settings::ArgParseSettings, err, err_code::Int = 1)
@@ -252,6 +256,7 @@ mutable struct ArgParseSettings
     preformatted_description::Bool
     preformatted_epilog::Bool
     exit_after_help::Bool
+    ignore_unrecognized_opts::Bool
 
     function ArgParseSettings(;prog::AbstractString = Base.source_path() ≢ nothing ?
                                                           basename(Base.source_path()) :
@@ -271,7 +276,8 @@ mutable struct ArgParseSettings
                                exc_handler::Function = default_handler,
                                preformatted_description::Bool = false,
                                preformatted_epilog::Bool = false,
-                               exit_after_help::Bool = !isinteractive()
+                               exit_after_help::Bool = !isinteractive(),
+                               ignore_unrecognized_opts::Bool = false
                                )
         fromfile_prefix_chars = check_prefix_chars(fromfile_prefix_chars)
         return new(
@@ -280,7 +286,7 @@ mutable struct ArgParseSettings
             suppress_warnings, allow_ambiguous_opts, commands_are_required,
             copy(std_groups), "", ArgParseTable(), exc_handler,
             preformatted_description, preformatted_epilog,
-            exit_after_help
+            exit_after_help, ignore_unrecognized_opts
             )
     end
 end
@@ -356,6 +362,12 @@ function check_nargs_and_action(nargs::ArgConsumerType, action::Symbol)
     return true
 end
 
+function check_ignore_unrecognized_opts(settings::ArgParseSettings, is_opt::Bool)
+    !is_opt && settings.ignore_unrecognized_opts &&
+        error("cannot use ignore_unrecognized_opts=true with positional arguments")
+    return true
+end
+
 function check_long_opt_name(name::AbstractString, settings::ArgParseSettings)
     '=' ∈ name            && error("illegal option name: $name (contains '=')")
     occursin(r"\s", name) && error("illegal option name: $name (contains whitespace)")
@@ -920,6 +932,8 @@ function add_arg_field!(settings::ArgParseSettings, name::ArgName; desc...)
 
     check_nargs_and_action(nargs, action)
 
+    check_ignore_unrecognized_opts(settings, is_opt)
+
     new_arg = ArgParseField()
 
     is_flag = is_flag_action(action)

test/argparse_test02.jl

@@ -262,6 +262,10 @@ for s = [ap_settings2(), ap_settings2b(), ap_settings2c(), ap_settings2d(), ap_s
     @ap_test_throws ap_test2(["--opt="])
     @ap_test_throws ap_test2(["--opt", "", "X", "Y"])
     @ap_test_throws ap_test2(["--opt", "1e-2", "X", "Y"])
+    @ap_test_throws ap_test2(["X", "Y", "-z"])
+    @ap_test_throws ap_test2(["X", "Y", "-z", "a b c"])
+    @ap_test_throws ap_test2(["X", "Y", "--zzz"])
+    @ap_test_throws ap_test2(["X", "Y", "--zzz", "a b c"])
 
     @ee_test_throws @add_arg_table!(s, "required_arg_after_optional_args", required = true)
     # wrong default

test/argparse_test03.jl

@@ -14,10 +14,7 @@ end
 Base.show(io::IO, ::Type{CustomType}) = print(io, "CustomType")
 Base.show(io::IO, c::CustomType) = print(io, "CustomType()")
 
-function ap_settings3()
-
-    s = ArgParseSettings("Test 3 for ArgParse.jl",
-                         exc_handler = ArgParse.debug_handler)
+function ap_add_table3!(s::ArgParseSettings)
 
     @add_arg_table! s begin
         "--opt1"
@@ -72,11 +69,30 @@ function ap_settings3()
             help = "either X or Y; all XY's are " *
                    "stored in chunks"
     end
+end
+
+function ap_settings3()
+
+    s = ArgParseSettings("Test 3 for ArgParse.jl",
+                         exc_handler = ArgParse.debug_handler)
+
+    ap_add_table3!(s)
 
     return s
 end
 
-let s = ap_settings3()
+function ap_settings3b()
+
+    s = ArgParseSettings("Test 3 for ArgParse.jl",
+                         exc_handler = ArgParse.debug_handler,
+                         ignore_unrecognized_opts = true)
+
+    ap_add_table3!(s)
+
+    return s
+end
+
+function runtest(s, ignore)
     ap_test3(args) = parse_args(args, s)
 
     ## ugly workaround for the change of printing Vectors in julia 1.6,
@@ -127,6 +143,17 @@ let s = ap_settings3()
     @ap_test_throws ap_test3(["--custom", "default"])
     @ap_test_throws ap_test3(["--oddint", "0"])
     @ap_test_throws ap_test3(["--collect", "0.5"])
+    if ignore
+        ap_test3(["--foobar"])
+        @test ap_test3(["--foobar"]) == Dict{String,Any}("O_stack"=>String[], "k"=>0, "u"=>0, "array"=>[7, 3, 2], "custom"=>CustomType(), "oddint"=>1, "collect"=>[], "awk"=>Any[Any["X"]])
+        @test ap_test3(["--foobar", "1"]) == Dict{String,Any}("O_stack"=>String[], "k"=>0, "u"=>0, "array"=>[7, 3, 2], "custom"=>CustomType(), "oddint"=>1, "collect"=>[], "awk"=>Any[Any["X"]])
+        @test ap_test3(["--foobar", "a b c", "--opt1", "--awk", "X", "X", "--opt2", "--opt2", "-k", "--coll", "5", "-u", "--array=[4]", "--custom", "custom", "--collect", "3", "--awkward-option=Y", "X", "--opt1", "--oddint", "-1"]) ==
+        Dict{String,Any}("O_stack"=>String["O1", "O2", "O2", "O1"], "k"=>42, "u"=>42.0, "array"=>[4], "custom"=>CustomType(), "oddint"=>-1, "collect"=>[5, 3], "awk"=>Any[Any["X"], Any["X", "X"], Any["Y", "X"]])
+    else
+        @ap_test_throws ap_test3(["--foobar"])
+        @ap_test_throws ap_test3(["--foobar", "1"])
+        @ap_test_throws ap_test3(["--foobar", "a b c", "--opt1", "--awk", "X", "X", "--opt2", "--opt2", "-k", "--coll", "5", "-u", "--array=[4]", "--custom", "custom", "--collect", "3", "--awkward-option=Y", "X", "--opt1", "--oddint", "-1"])
+    end
 
     # invalid option name
     @ee_test_throws @add_arg_table!(s, "-2", action = :store_true)
@@ -163,4 +190,8 @@ let s = ap_settings3()
 
 end
 
+for (s, ignore) = [(ap_settings3(), false), (ap_settings3b(), true)]
+    runtest(s, ignore)
+end
+
 end

test/argparse_test13.jl

@@ -0,0 +1,19 @@
+# test 13: setting ignore_unrecognized_opts with positional arguments is an error
+
+@testset "test 13" begin
+s = ArgParseSettings(description = "Test 13 for ArgParse.jl",
+                     epilog = "Have fun!",
+                     version = "Version 1.0",
+                     add_version = true,
+                     exc_handler = ArgParse.debug_handler,
+                     ignore_unrecognized_opts = true)
+
+@ee_test_throws @add_arg_table! s begin
+    "arg1"
+        nargs = 2                        # eats up two arguments; puts the result in a Vector
+        help = "first argument, two " *
+               "entries at once"
+        required = true
+end
+
+end

test/runtests.jl

@@ -2,7 +2,7 @@ module ArgParseTests
 
 include("common.jl")
 
-for i = 1:12
+for i = 1:13
     try
         s_i = lpad(string(i), 2, "0")
         include("argparse_test$s_i.jl")