argparse/tests/argparse.c

#include "malunal/microtest.h"
#include "malunal/argparse.h"

#define PARSE(parser, result, ...)                                      \
  argparser_parse(                                                      \
    (parser),                                                           \
    (malunal_int32_t)(                                                  \
      sizeof((malunal_cstr_t[]){ __VA_ARGS__ }) / sizeof(malunal_str_t) \
    ),                                                                  \
    (malunal_cstr_t[]){ __VA_ARGS__ },                                  \
    (result)                                                            \
  )

static
malunal_bool_t
view_is(
  strview_t      view,
  malunal_cstr_t text
) {
  strview_t other = strview_from_cstr(text);
  return strview_equals(&view, &other);
}

/* -------------------------------------------------------------------------
 * Parser construction.
 * ---------------------------------------------------------------------- */

MICROTEST(argparser_add_option, accepts_flag_with_short_and_long) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);

  error_t err = argparser_add_option(&parser, &ARGOPTION_FLAG(
    .short_name = 'v',
    .long_name  = "verbose"
  ));
  MICROTEST_EXPECT_NULL(err.domain);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_option_without_names) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);

  error_t err = argparser_add_option(&parser, &ARGOPTION_FLAG(
    .value_type = ARGOPTION_TYPE_STRING
  ));
  MICROTEST_EXPECT_NOT_NULL(err.domain);
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_long_name_with_dashes) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);

  error_t err = argparser_add_option(&parser, &ARGOPTION_FLAG(
    .long_name = "--verbose"
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_duplicate_short_name) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(
    .short_name = 'v',
    .long_name  = "verbose"
  ));

  error_t err = argparser_add_option(&parser, &ARGOPTION_FLAG(
    .short_name = 'v',
    .long_name  = "version"
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_DUPLICATE_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_duplicate_long_name) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(
    .short_name = 'v',
    .long_name  = "verbose"
  ));

  error_t err = argparser_add_option(&parser, &ARGOPTION_FLAG(
    .long_name = "verbose"
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_DUPLICATE_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_conflict_with_builtin_help) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);

  error_t err = argparser_add_option(&parser, &ARGOPTION_FLAG(
    .short_name = 'h',
    .long_name  = "host"
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_DUPLICATE_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_positional_named_like_option) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(
    .long_name  = "input",
    .value_type = ARGOPTION_TYPE_STRING
  ));

  error_t err = argparser_add_option(&parser, &ARGOPTION_POSITIONAL(
    .long_name  = "input",
    .value_type = ARGOPTION_TYPE_STRING
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_DUPLICATE_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_required_flag) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);

  error_t err = argparser_add_option(&parser, &ARGOPTION_FLAG(
    .short_name = 'v',
    .required   = true
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_flag_typed_positional) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);

  error_t err = argparser_add_option(&parser, &ARGOPTION_POSITIONAL(
    .long_name  = "input",
    .value_type = ARGOPTION_TYPE_FLAG
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_positional_after_multiple) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(
    .long_name  = "files",
    .value_type = ARGOPTION_TYPE_STRING,
    .multiple   = true
  ));

  error_t err = argparser_add_option(&parser, &ARGOPTION_POSITIONAL(
    .long_name  = "extra",
    .value_type = ARGOPTION_TYPE_STRING
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_required_positional_after_optional) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(
    .long_name  = "first",
    .value_type = ARGOPTION_TYPE_STRING
  ));

  error_t err = argparser_add_option(&parser, &ARGOPTION_POSITIONAL(
    .long_name  = "second",
    .value_type = ARGOPTION_TYPE_STRING,
    .required   = true
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_unconvertible_default) {
  argparser_t parser;
  argparser_init("prog", null, null, &parser);

  error_t err = argparser_add_option(&parser, &ARGOPTION_FLAG(
    .long_name     = "jobs",
    .value_type    = ARGOPTION_TYPE_NUMBER,
    .default_value = "many"
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_option, rejects_positional_when_subcommands_exist) {
  argparser_t      parser;
  argparser_mptr_t sub;
  argparser_init("git", null, null, &parser);
  argparser_add_subcommand(&parser, "commit", null, &sub);

  error_t err = argparser_add_option(&parser, &ARGOPTION_POSITIONAL(
    .long_name  = "x",
    .value_type = ARGOPTION_TYPE_STRING
  ));
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_subcommand, rejects_when_positionals_exist) {
  argparser_t      parser;
  argparser_mptr_t sub;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(
    .long_name  = "x",
    .value_type = ARGOPTION_TYPE_STRING
  ));

  error_t err = argparser_add_subcommand(&parser, "sub", null, &sub);
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_DEFINITION);

  argparser_free(&parser);
}

MICROTEST(argparser_add_subcommand, rejects_duplicate_name) {
  argparser_t      parser;
  argparser_mptr_t first;
  argparser_mptr_t second;
  argparser_init("git", null, null, &parser);
  argparser_add_subcommand(&parser, "build", null, &first);

  error_t err = argparser_add_subcommand(&parser, "build", null, &second);
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_DUPLICATE_DEFINITION);

  argparser_free(&parser);
}


/* -------------------------------------------------------------------------
 * Parsing: flags.
 * ---------------------------------------------------------------------- */

MICROTEST(argparser_parse, short_and_long_flags_are_recognized) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'a', .long_name = "all"));
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'b', .long_name = "bold"));
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'c', .long_name = "color"));

  error_t err = PARSE(&parser, &result, "prog", "-a", "--bold");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_TRUE(argresult_has(&result, "all"));
  MICROTEST_EXPECT_TRUE(argresult_has(&result, "-b"));
  MICROTEST_EXPECT_TRUE(argresult_has(&result, "--bold"));
  MICROTEST_EXPECT_FALSE(argresult_has(&result, "color"));

  malunal_bool_t color = true;
  MICROTEST_EXPECT_NULL(argresult_get_boolean(&result, "color", &color).domain);
  MICROTEST_EXPECT_FALSE(color);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, flags_count_occurrences_and_cluster) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'v', .long_name = "verbose"));
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'q'));

  error_t err = PARSE(&parser, &result, "prog", "-vvq", "--verbose");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_EQ(argresult_count(&result, "verbose"), (malunal_size_t)3);
  MICROTEST_EXPECT_EQ(argresult_count(&result, "q"), (malunal_size_t)1);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, flag_with_inline_value_fails) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'v', .long_name = "verbose"));

  error_t err = PARSE(&parser, &result, "prog", "--verbose=yes");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_UNEXPECTED_VALUE);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, unknown_options_fail) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);

  error_t err = PARSE(&parser, &result, "prog", "--bogus");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_UNKNOWN_OPTION);
  argresult_free(&result);

  err = PARSE(&parser, &result, "prog", "-z");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_UNKNOWN_OPTION);
  argresult_free(&result);

  argparser_free(&parser);
}

MICROTEST(argparser_parse, help_flag_is_reported) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);

  error_t err = PARSE(&parser, &result, "prog", "-h");
  MICROTEST_EXPECT_NOT_NULL(err.domain);
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_HELP_REQUESTED);
  argresult_free(&result);

  err = PARSE(&parser, &result, "prog", "--help");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_HELP_REQUESTED);
  argresult_free(&result);

  argparser_free(&parser);
}


/* -------------------------------------------------------------------------
 * Parsing: value-bearing options.
 * ---------------------------------------------------------------------- */

MICROTEST(argparser_parse, string_option_accepts_every_spelling) {
  argparser_t parser;
  argresult_t result;
  strview_t   value;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(
    .short_name = 'o',
    .long_name  = "output",
    .value_type = ARGOPTION_TYPE_STRING
  ));

  malunal_cstr_t spellings[][3] = {
    { "-o", "out.txt", null },
    { "-oout.txt", null, null },
    { "-o=out.txt", null, null },
    { "--output", "out.txt", null },
    { "--output=out.txt", null, null },
  };

  malunal_size_t index;
  for (index = 0; index < sizeof(spellings) / sizeof(spellings[0]); index++) {
    malunal_cstr_t  argv[3] = { "prog", spellings[index][0], spellings[index][1] };
    malunal_int32_t argc    = spellings[index][1] != null ? 3 : 2;

    error_t err = argparser_parse(&parser, argc, argv, &result);
    MICROTEST_EXPECT_NULL(err.domain);
    MICROTEST_EXPECT_NULL(argresult_get_string(&result, "output", &value).domain);
    MICROTEST_EXPECT_TRUE(view_is(value, "out.txt"));
    argresult_free(&result);
  }

  argparser_free(&parser);
}

MICROTEST(argparser_parse, flag_cluster_ends_with_value_option) {
  argparser_t      parser;
  argparser_mptr_t commit;
  argresult_t      result;
  strview_t        message;
  argparser_init("git", null, null, &parser);
  argparser_add_subcommand(&parser, "commit", null, &commit);
  argparser_add_option(commit, &ARGOPTION_FLAG(.short_name = 'a', .long_name = "all"));
  argparser_add_option(commit, &ARGOPTION_FLAG(
    .short_name = 'm',
    .long_name  = "message",
    .value_type = ARGOPTION_TYPE_STRING,
    .required   = true
  ));

  error_t err = PARSE(&parser, &result, "git", "commit", "-am", "fix bug");
  MICROTEST_EXPECT_NULL(err.domain);

  argresult_iptr_t sub = argresult_subresult(&result);
  MICROTEST_EXPECT_TRUE(argresult_has(sub, "all"));
  MICROTEST_EXPECT_NULL(argresult_get_string(sub, "message", &message).domain);
  MICROTEST_EXPECT_TRUE(view_is(message, "fix bug"));

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, single_option_keeps_last_value) {
  argparser_t parser;
  argresult_t result;
  strview_t   value;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(
    .short_name = 'o',
    .value_type = ARGOPTION_TYPE_STRING
  ));

  error_t err = PARSE(&parser, &result, "prog", "-o", "first", "-o", "second");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_EQ(argresult_count(&result, "o"), (malunal_size_t)1);
  argresult_get_string(&result, "o", &value);
  MICROTEST_EXPECT_TRUE(view_is(value, "second"));

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, multiple_option_appends_values) {
  argparser_t    parser;
  argresult_t    result;
  strview_t      value;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(
    .short_name = 'I',
    .long_name  = "include",
    .value_type = ARGOPTION_TYPE_STRING,
    .multiple   = true
  ));

  error_t err = PARSE(&parser, &result, "prog", "-Ifoo", "--include", "bar", "--include=baz");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_EQ(argresult_count(&result, "include"), (malunal_size_t)3);

  argresult_get_string_at(&result, "include", 0, &value);
  MICROTEST_EXPECT_TRUE(view_is(value, "foo"));
  argresult_get_string_at(&result, "include", 1, &value);
  MICROTEST_EXPECT_TRUE(view_is(value, "bar"));
  argresult_get_string_at(&result, "include", 2, &value);
  MICROTEST_EXPECT_TRUE(view_is(value, "baz"));

  err = argresult_get_string_at(&result, "include", 3, &value);
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_OUT_OF_RANGE);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, typed_options_convert_values) {
  argparser_t      parser;
  argresult_t      result;
  malunal_int64_t  number   = 0;
  malunal_double_t floating = 0.0;
  malunal_bool_t   boolean  = false;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.long_name = "jobs", .value_type = ARGOPTION_TYPE_NUMBER));
  argparser_add_option(&parser, &ARGOPTION_FLAG(.long_name = "scale", .value_type = ARGOPTION_TYPE_FLOAT));
  argparser_add_option(&parser, &ARGOPTION_FLAG(.long_name = "color", .value_type = ARGOPTION_TYPE_BOOLEAN));

  error_t err = PARSE(&parser, &result, "prog", "--jobs", "-4", "--scale=2.5", "--color", "YES");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_NULL(argresult_get_number(&result, "jobs", &number).domain);
  MICROTEST_EXPECT_EQ(number, (malunal_int64_t)-4);
  MICROTEST_EXPECT_NULL(argresult_get_float(&result, "scale", &floating).domain);
  MICROTEST_EXPECT_TRUE(floating > 2.49 && floating < 2.51);
  MICROTEST_EXPECT_NULL(argresult_get_boolean(&result, "color", &boolean).domain);
  MICROTEST_EXPECT_TRUE(boolean);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, invalid_values_fail) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.long_name = "jobs", .value_type = ARGOPTION_TYPE_NUMBER));
  argparser_add_option(&parser, &ARGOPTION_FLAG(.long_name = "color", .value_type = ARGOPTION_TYPE_BOOLEAN));

  error_t err = PARSE(&parser, &result, "prog", "--jobs=abc");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_VALUE);
  argresult_free(&result);

  err = PARSE(&parser, &result, "prog", "--color=maybe");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_INVALID_VALUE);
  argresult_free(&result);

  argparser_free(&parser);
}

MICROTEST(argparser_parse, option_missing_value_fails) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'o', .value_type = ARGOPTION_TYPE_STRING));
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'v'));

  error_t err = PARSE(&parser, &result, "prog", "-o");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_MISSING_VALUE);
  argresult_free(&result);

  err = PARSE(&parser, &result, "prog", "-o", "-v");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_MISSING_VALUE);
  argresult_free(&result);

  argparser_free(&parser);
}

MICROTEST(argparser_parse, long_options_match_unique_prefixes) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.long_name = "verbose"));
  argparser_add_option(&parser, &ARGOPTION_FLAG(.long_name = "version"));
  argparser_add_option(&parser, &ARGOPTION_FLAG(.long_name = "quiet"));

  error_t err = PARSE(&parser, &result, "prog", "--q", "--verb");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_TRUE(argresult_has(&result, "quiet"));
  MICROTEST_EXPECT_TRUE(argresult_has(&result, "verbose"));
  argresult_free(&result);

  err = PARSE(&parser, &result, "prog", "--ver");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_AMBIGUOUS_OPTION);
  argresult_free(&result);

  argparser_free(&parser);
}

MICROTEST(argparser_parse, required_option_missing_fails) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(
    .long_name  = "jobs",
    .value_type = ARGOPTION_TYPE_NUMBER,
    .required   = true
  ));

  error_t err = PARSE(&parser, &result, "prog");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_MISSING_REQUIRED_OPTION);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, defaults_apply_when_absent) {
  argparser_t     parser;
  argresult_t     result;
  malunal_int64_t jobs = 0;
  strview_t       mode;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(
    .long_name     = "jobs",
    .value_type    = ARGOPTION_TYPE_NUMBER,
    .default_value = "8"
  ));
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(
    .long_name     = "mode",
    .value_type    = ARGOPTION_TYPE_STRING,
    .default_value = "debug"
  ));

  error_t err = PARSE(&parser, &result, "prog");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_FALSE(argresult_has(&result, "jobs"));
  MICROTEST_EXPECT_EQ(argresult_count(&result, "jobs"), (malunal_size_t)1);
  MICROTEST_EXPECT_NULL(argresult_get_number(&result, "jobs", &jobs).domain);
  MICROTEST_EXPECT_EQ(jobs, (malunal_int64_t)8);
  MICROTEST_EXPECT_NULL(argresult_get_string(&result, "mode", &mode).domain);
  MICROTEST_EXPECT_TRUE(view_is(mode, "debug"));
  argresult_free(&result);

  err = PARSE(&parser, &result, "prog", "--jobs", "2", "release");
  MICROTEST_EXPECT_NULL(err.domain);
  argresult_get_number(&result, "jobs", &jobs);
  MICROTEST_EXPECT_EQ(jobs, (malunal_int64_t)2);
  argresult_get_string(&result, "mode", &mode);
  MICROTEST_EXPECT_TRUE(view_is(mode, "release"));
  argresult_free(&result);

  argparser_free(&parser);
}


/* -------------------------------------------------------------------------
 * Parsing: positionals.
 * ---------------------------------------------------------------------- */

MICROTEST(argparser_parse, positionals_fill_in_order_around_options) {
  argparser_t parser;
  argresult_t result;
  strview_t   src;
  strview_t   dst;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'v'));
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(.long_name  = "src", .value_type = ARGOPTION_TYPE_STRING, .required = true));
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(.long_name  = "dst", .value_type = ARGOPTION_TYPE_STRING, .required = true));

  error_t err = PARSE(&parser, &result, "prog", "a.txt", "-v", "b.txt");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_TRUE(argresult_has(&result, "v"));
  argresult_get_string(&result, "src", &src);
  argresult_get_string(&result, "dst", &dst);
  MICROTEST_EXPECT_TRUE(view_is(src, "a.txt"));
  MICROTEST_EXPECT_TRUE(view_is(dst, "b.txt"));

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, multiple_positional_collects_remaining) {
  argparser_t parser;
  argresult_t result;
  strview_t   value;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(.long_name  = "cmd", .value_type = ARGOPTION_TYPE_STRING, .required = true));
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(.long_name  = "files", .value_type = ARGOPTION_TYPE_STRING, .multiple = true));

  error_t err = PARSE(&parser, &result, "prog", "cat", "a", "b", "c");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_EQ(argresult_count(&result, "files"), (malunal_size_t)3);
  argresult_get_string_at(&result, "files", 2, &value);
  MICROTEST_EXPECT_TRUE(view_is(value, "c"));

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, required_positional_missing_fails) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(.long_name  = "files", .value_type = ARGOPTION_TYPE_STRING, .required = true, .multiple = true));

  error_t err = PARSE(&parser, &result, "prog");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_MISSING_REQUIRED_POSITIONAL);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, extra_positional_fails) {
  argparser_t parser;
  argresult_t result;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(.long_name  = "only", .value_type = ARGOPTION_TYPE_STRING));

  error_t err = PARSE(&parser, &result, "prog", "one", "two");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_TOO_MANY_POSITIONALS);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, negative_numbers_are_values) {
  argparser_t      parser;
  argresult_t      result;
  malunal_double_t value = 0.0;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(.long_name  = "n", .value_type = ARGOPTION_TYPE_FLOAT, .required = true));

  error_t err = PARSE(&parser, &result, "prog", "-1.5");
  MICROTEST_EXPECT_NULL(err.domain);
  argresult_get_float(&result, "n", &value);
  MICROTEST_EXPECT_TRUE(value < -1.49 && value > -1.51);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, double_dash_ends_options) {
  argparser_t parser;
  argresult_t result;
  strview_t   value;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'v'));
  argparser_add_option(&parser, &ARGOPTION_POSITIONAL(.long_name  = "file", .value_type = ARGOPTION_TYPE_STRING, .required = true));

  error_t err = PARSE(&parser, &result, "prog", "-v", "--", "-v");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_EQ(argresult_count(&result, "v"), (malunal_size_t)1);
  argresult_get_string(&result, "file", &value);
  MICROTEST_EXPECT_TRUE(view_is(value, "-v"));

  argresult_free(&result);
  argparser_free(&parser);
}


/* -------------------------------------------------------------------------
 * Parsing: subcommands.
 * ---------------------------------------------------------------------- */

MICROTEST(argparser_parse, subcommand_is_dispatched_after_parent_options) {
  argparser_t      parser;
  argparser_mptr_t push;
  argparser_mptr_t commit;
  argresult_t      result;
  strview_t        remote;
  argparser_init("git", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'v'));
  argparser_add_subcommand(&parser, "commit", null, &commit);
  argparser_add_subcommand(&parser, "push", null, &push);
  argparser_add_option(push, &ARGOPTION_FLAG(.short_name = 'f', .long_name = "force"));
  argparser_add_option(push, &ARGOPTION_POSITIONAL(.long_name  = "remote", .value_type = ARGOPTION_TYPE_STRING));
  argparser_add_option(push, &ARGOPTION_POSITIONAL(.long_name  = "refs", .value_type = ARGOPTION_TYPE_STRING, .multiple = true));

  error_t err = PARSE(&parser, &result, "git", "-v", "push", "--force", "origin", "main", "dev");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_TRUE(argresult_has(&result, "v"));
  MICROTEST_EXPECT_TRUE(strcmp(argresult_subcommand(&result), "push") == 0);

  argresult_iptr_t sub = argresult_subresult(&result);
  MICROTEST_EXPECT_NOT_NULL(sub);
  MICROTEST_EXPECT_TRUE(argresult_has(sub, "force"));
  argresult_get_string(sub, "remote", &remote);
  MICROTEST_EXPECT_TRUE(view_is(remote, "origin"));
  MICROTEST_EXPECT_EQ(argresult_count(sub, "refs"), (malunal_size_t)2);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, no_subcommand_leaves_subresult_null) {
  argparser_t      parser;
  argparser_mptr_t commit;
  argresult_t      result;
  argparser_init("git", null, null, &parser);
  argparser_add_subcommand(&parser, "commit", null, &commit);

  error_t err = PARSE(&parser, &result, "git");
  MICROTEST_EXPECT_NULL(err.domain);
  MICROTEST_EXPECT_NULL(argresult_subcommand(&result));
  MICROTEST_EXPECT_NULL(argresult_subresult(&result));

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, unknown_subcommand_fails) {
  argparser_t      parser;
  argparser_mptr_t commit;
  argresult_t      result;
  argparser_init("git", null, null, &parser);
  argparser_add_subcommand(&parser, "commit", null, &commit);

  error_t err = PARSE(&parser, &result, "git", "bogus");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_UNKNOWN_SUBCOMMAND);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST(argparser_parse, sibling_subcommands_do_not_share_options) {
  argparser_t      parser;
  argparser_mptr_t commit;
  argparser_mptr_t push;
  argresult_t      result;
  argparser_init("git", null, null, &parser);
  argparser_add_subcommand(&parser, "commit", null, &commit);
  argparser_add_subcommand(&parser, "push", null, &push);
  argparser_add_option(commit, &ARGOPTION_FLAG(.short_name = 'm', .value_type = ARGOPTION_TYPE_STRING));

  error_t err = PARSE(&parser, &result, "git", "push", "-m", "nope");
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_UNKNOWN_OPTION);

  argresult_free(&result);
  argparser_free(&parser);
}


/* -------------------------------------------------------------------------
 * Reading results.
 * ---------------------------------------------------------------------- */

MICROTEST(argresult_get, reports_lookup_errors) {
  argparser_t     parser;
  argresult_t     result;
  malunal_int64_t number = 0;
  strview_t       value;
  argparser_init("prog", null, null, &parser);
  argparser_add_option(&parser, &ARGOPTION_FLAG(.short_name = 'o', .value_type = ARGOPTION_TYPE_STRING));

  error_t err = PARSE(&parser, &result, "prog");
  MICROTEST_EXPECT_NULL(err.domain);

  err = argresult_get_string(&result, "missing", &value);
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_UNKNOWN_NAME);
  err = argresult_get_number(&result, "o", &number);
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_TYPE_MISMATCH);
  err = argresult_get_string(&result, "o", &value);
  MICROTEST_EXPECT_EQ(err.code, ARGPARSE_ERROR_NOT_PRESENT);

  argresult_free(&result);
  argparser_free(&parser);
}

MICROTEST_MAIN()