fix some doc and error strings (#899)

Update some doc strings and error output for clarity

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

README.md

@@ -24,6 +24,8 @@ set with a simple and intuitive interface.
 
 ## Table of Contents
 
+- [CLI11: Command line parser for C++11](#cli11-command-line-parser-for-c11)
+  - [Table of Contents](#table-of-contents)
   - [Background](#background)
     - [Introduction](#introduction)
     - [Why write another CLI parser?](#why-write-another-cli-parser)
@@ -40,21 +42,23 @@ set with a simple and intuitive interface.
         - [Validator operations](#validator-operations)
         - [Custom Validators](#custom-validators)
         - [Querying Validators](#querying-validators)
-      - [Getting Results](#getting-results)
+      - [Getting results](#getting-results)
     - [Subcommands](#subcommands)
       - [Subcommand options](#subcommand-options)
-    - [Option groups](#option-groups)
       - [Callbacks](#callbacks)
+      - [Option groups](#option-groups)
     - [Configuration file](#configuration-file)
     - [Inheriting defaults](#inheriting-defaults)
     - [Formatting](#formatting)
     - [Subclassing](#subclassing)
     - [How it works](#how-it-works)
+      - [Example](#example-1)
     - [Unicode support](#unicode-support)
+      - [Note on using Unicode paths](#note-on-using-unicode-paths)
     - [Utilities](#utilities)
     - [Other libraries](#other-libraries)
   - [API](#api)
-- [Examples](#Examples)
+  - [Examples](#examples)
   - [Contribute](#contribute)
   - [License](#license)
 
@@ -224,7 +228,7 @@ include(FetchContent)
 FetchContent_Declare(
   cli11
   GIT_REPOSITORY https://github.com/CLIUtils/CLI11
-  GIT_TAG        v2.2.0
+  GIT_TAG        v2.3.2
 )
 
 FetchContent_MakeAvailable(cli11)
@@ -265,6 +269,10 @@ In some cases certain clang compilations may require linking against `libc++fs`.
 These situations have not been encountered so the specific situations requiring
 them are unknown yet.
 
+If building with WASI it is necessary to add the flag
+`-lc-printscan-long-double` to the build to allow long double support. See #841
+for more details.
+
 </p></details>
 </br>
 
@@ -287,6 +295,9 @@ int main() {
 }
 ```
 
+The 🚧 `CLI11_PARSE(app)` is only available in main currently and not in a
+release.
+
 <details><summary>Note: If you don't like macros, this is what that macro expands to: (click to expand)</summary><p>
 
 ```cpp
@@ -309,7 +320,8 @@ interfere.
 <details><summary>Note: Why are argc and argv not used? (click to expand)</summary><p>
 
 `argc` and `argv` may contain incorrect information on Windows when unicode text
-is passed in. Check out a section on [unicode support](#unicode-support) below.
+is passed in. Check out a section on [unicode support](#unicode-support)🚧
+below.
 
 If this is not a concern, you can explicitly pass `argc` and `argv` from main or
 from an external preprocessor of CLI arguments to `parse`:
@@ -514,8 +526,8 @@ Before parsing, you can set the following options:
 - `->envname(name)`: Gets the value from the environment if present and not
   passed on the command line.
 - `->group(name)`: The help group to put the option in. No effect for positional
-  options. Defaults to `"Options"`. `""` will not show up in the help print
+  options. Defaults to `"Options"`. Options given an empty string will not show
-  (hidden).
+  up in the help print (hidden).
 - `->ignore_case()`: Ignore the case on the command line (also works on
   subcommands, does not affect arguments).
 - `->ignore_underscore()`: Ignore any underscores in the options names (also
@@ -901,12 +913,15 @@ not used in performance critical code:
 
 ### Subcommands
 
-Subcommands are supported, and can be nested infinitely. To add a subcommand,
+Subcommands are keywords that invoke a new set of options and features. For
-call the `add_subcommand` method with a name and an optional description. This
+example, the `git` command has a long series of subcommands, like `add` and
-gives a pointer to an `App` that behaves just like the main app, and can take
+`commit`. Each can have its own options and implementations. Subcommands are
-options or further subcommands. Add `->ignore_case()` to a subcommand to allow
+supported in CLI11, and can be nested infinitely. To add a subcommand, call the
-any variation of caps to also be accepted. `->ignore_underscore()` is similar,
+`add_subcommand` method with a name and an optional description. This gives a
-but for underscores. Children inherit the current setting from the parent. You
+pointer to an `App` that behaves just like the main app, and can take options or
+further subcommands. Add `->ignore_case()` to a subcommand to allow any
+variation of caps to also be accepted. `->ignore_underscore()` is similar, but
+for underscores. Children inherit the current setting from the parent. You
 cannot add multiple matching subcommand names at the same level (including
 `ignore_case` and `ignore_underscore`).
 
@@ -1109,8 +1124,8 @@ option_groups. These are:
   returns a pointer to the created option. Expands subcommands.
 - `.failure_message(func)`: Set the failure message function. Two provided:
   `CLI::FailureMessage::help` and `CLI::FailureMessage::simple` (the default).
-- `.group(name)`: Set a group name, defaults to `"Subcommands"`. Setting `""`
+- `.group(name)`: Set a group name, defaults to `"Subcommands"`. Setting an
-  will be hide the subcommand.
+  empty string for the name will be hide the subcommand.
 - `[option_name]`: retrieve a const pointer to an option given by `option_name`
   for Example `app["--flag1"]` will get a pointer to the option for the
   "--flag1" value, `app["--flag1"]->as<bool>()` will get the results of the

book/chapters/options.md

@@ -215,7 +215,7 @@ that to add option modifiers. A full listing of the option modifiers:
 | `->needs(opt)`                                          | This option requires another option to also be present, opt is an `Option` pointer or a string with the name of the option. Can be removed with `->remove_needs(opt)`                                                                                                                                                                                                                                                                                     |
 | `->excludes(opt)`                                       | This option cannot be given with `opt` present, opt is an `Option` pointer or a string with the name of the option. Can be removed with `->remove_excludes(opt)`                                                                                                                                                                                                                                                                                          |
 | `->envname(name)`                                       | Gets the value from the environment if present and not passed on the command line.                                                                                                                                                                                                                                                                                                                                                                        |
-| `->group(name)`                                         | The help group to put the option in. No effect for positional options. Defaults to `"Options"`. `"Hidden"` will not show up in the help print.                                                                                                                                                                                                                                                                                                            |
+| `->group(name)`                                         | The help group to put the option in. No effect for positional options. Defaults to `"Options"`. Options given an empty string for the group name will not show up in the help print.                                                                                                                                                                                                                                                                      |
 | `->description(string)`                                 | Set/change the description                                                                                                                                                                                                                                                                                                                                                                                                                                |
 | `->ignore_case()`                                       | Ignore the case on the command line (also works on subcommands, does not affect arguments).                                                                                                                                                                                                                                                                                                                                                               |
 | `->ignore_underscore()`                                 | Ignore any underscores on the command line (also works on subcommands, does not affect arguments).                                                                                                                                                                                                                                                                                                                                                        |

include/CLI/Error.hpp

@@ -123,6 +123,9 @@ class BadNameString : public ConstructionError {
     CLI11_ERROR_DEF(ConstructionError, BadNameString)
     CLI11_ERROR_SIMPLE(BadNameString)
     static BadNameString OneCharName(std::string name) { return BadNameString("Invalid one char name: " + name); }
+    static BadNameString MissingDash(std::string name) {
+        return BadNameString("Long names strings require 2 dashes " + name);
+    }
     static BadNameString BadLongName(std::string name) { return BadNameString("Bad long name: " + name); }
     static BadNameString DashesOnly(std::string name) {
         return BadNameString("Must have a name, not just dashes: " + name);

include/CLI/impl/Split_inl.hpp

@@ -114,6 +114,8 @@ get_names(const std::vector<std::string> &input) {
         if(name.length() > 1 && name[0] == '-' && name[1] != '-') {
             if(name.length() == 2 && valid_first_char(name[1]))
                 short_names.emplace_back(1, name[1]);
+            else if(name.length() > 2)
+                throw BadNameString::MissingDash(name);
             else
                 throw BadNameString::OneCharName(name);
         } else if(name.length() > 2 && name.substr(0, 2) == "--") {

tests/AppTest.cpp

@@ -641,6 +641,28 @@ TEST_CASE_METHOD(TApp, "StrangeOptionNames", "[app]") {
     CHECK(app["--{}"]->as<int>() == 5);
 }
 
+TEST_CASE_METHOD(TApp, "singledash", "[app]") {
+    app.add_option("-t");
+    try {
+        app.add_option("-test");
+    } catch(const CLI::BadNameString &e) {
+        std::string str = e.what();
+        CHECK_THAT(str, Contains("2 dashes"));
+        CHECK_THAT(str, Contains("-test"));
+    } catch(...) {
+        CHECK(false);
+    }
+    try {
+        app.add_option("-!");
+    } catch(const CLI::BadNameString &e) {
+        std::string str = e.what();
+        CHECK_THAT(str, Contains("one char"));
+        CHECK_THAT(str, Contains("-!"));
+    } catch(...) {
+        CHECK(false);
+    }
+}
+
 TEST_CASE_METHOD(TApp, "FlagLikeOption", "[app]") {
     bool val{false};
     auto *opt = app.add_option("--flag", val)->type_size(0)->default_str("true");