Merge pull request #2820 from epage/option

fix(derive): Support SubcommandsNegateReqs

clap_derive/src/attrs.rs

@@ -717,9 +717,6 @@ impl Attrs {
                         if let Some(m) = res.find_method("default_value") {
                             abort!(m.name, "default_value is meaningless for Option")
                         }
-                        if let Some(m) = res.find_method("required") {
-                            abort!(m.name, "required is meaningless for Option")
-                        }
                     }
                     Ty::OptionOption => {
                         if res.is_positional() {

clap_derive/tests/options.rs

@@ -298,3 +298,42 @@ fn two_optional_vecs() {
 
     assert_eq!(Opt { arg: None, b: None }, Opt::parse_from(&["test"]));
 }
+
+#[test]
+fn required_option_type() {
+    #[derive(Debug, PartialEq, Eq, Clap)]
+    #[clap(setting(clap::AppSettings::SubcommandsNegateReqs))]
+    struct Opt {
+        #[clap(required = true)]
+        req_str: Option<String>,
+
+        #[clap(subcommand)]
+        cmd: Option<SubCommands>,
+    }
+
+    #[derive(Debug, PartialEq, Eq, Clap)]
+    enum SubCommands {
+        ExSub {
+            #[clap(short, long, parse(from_occurrences))]
+            verbose: u8,
+        },
+    }
+
+    assert_eq!(
+        Opt {
+            req_str: Some(("arg").into()),
+            cmd: None,
+        },
+        Opt::parse_from(&["test", "arg"])
+    );
+
+    assert_eq!(
+        Opt {
+            req_str: None,
+            cmd: Some(SubCommands::ExSub { verbose: 1 }),
+        },
+        Opt::parse_from(&["test", "ex-sub", "-v"])
+    );
+
+    assert!(Opt::try_parse_from(&["test"]).is_err());
+}

clap_derive/tests/ui/option_required.rs

@@ -1,21 +0,0 @@
-// Copyright 2018 Guillaume Pinot (@TeXitoi) <texitoi@texitoi.eu>
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-use clap::Clap;
-
-#[derive(Clap, Debug)]
-#[clap(name = "basic")]
-struct Opt {
-    #[clap(short, required = true)]
-    n: Option<u32>,
-}
-
-fn main() {
-    let opt = Opt::parse();
-    println!("{:?}", opt);
-}

clap_derive/tests/ui/option_required.stderr

@@ -1,5 +0,0 @@
-error: required is meaningless for Option
-  --> $DIR/option_required.rs:14:19
-   |
-14 |     #[clap(short, required = true)]
-   |                   ^^^^^^^^