refactor: moves code for ergonomics

src/errors.rs

@@ -11,6 +11,7 @@ pub type ClapResult<T> = Result<T, ClapError>;
 #[doc(hidden)]
 #[allow(non_snake_case)]
 pub mod error_builder {
+    use suggestions;
     use super::ClapError;
     use super::ClapErrorType as cet;
     use fmt::Format;
@@ -48,19 +49,29 @@ pub mod error_builder {
                            Format::Warning(arg.as_ref()),
                            usage.as_ref(),
                            Format::Good("--help")),
-            error_type: cet::InvalidValue,
+            error_type: cet::EmptyValue,
         }
     }
 
     /// Error occurs when some possible values were set, but clap found unexpected value
     pub fn InvalidValue<S>(bad_val: S,
+                           good_vals: &[S],
                            arg: S,
-                           valid_vals: S,
-                           did_you_mean: S,
                            usage: S)
                            -> ClapError
         where S: AsRef<str>
     {
+        let suffix = suggestions::did_you_mean_suffix(arg.as_ref(),
+                                                      good_vals.iter(),
+                                                      suggestions::DidYouMeanMessageStyle::EnumValue);
+
+        let mut sorted = vec![];
+        for v in good_vals {
+            sorted.push(v.as_ref());
+        }
+        sorted.sort();
+        let valid_values = sorted.iter()
+                                 .fold(String::new(), |a, name| a + &format!( " {}", name)[..]);
         ClapError {
             error: format!("{} '{}' isn't a valid value for '{}'\n\t\
                             [valid values:{}]\n\
@@ -70,8 +81,8 @@ pub mod error_builder {
                            Format::Error("error:"),
                            Format::Warning(bad_val.as_ref()),
                            Format::Warning(arg.as_ref()),
-                           valid_vals.as_ref(),
+                           valid_values,
-                           did_you_mean.as_ref(),
+                           suffix.0,
                            usage.as_ref(),
                            Format::Good("--help")),
             error_type: cet::InvalidValue,
@@ -280,7 +291,6 @@ pub mod error_builder {
             error_type: cet::UnexpectedMultipleUsage,
         }
     }
-
 }
 
 /// Command line argument parser error types

src/lib.rs

@@ -671,8 +671,9 @@ extern crate vec_map;
 #[cfg(feature = "yaml")]
 pub use yaml_rust::YamlLoader;
 pub use args::{Arg, ArgGroup, ArgMatches, SubCommand};
-pub use app::{App, AppSettings, ClapError, ClapErrorType};
+pub use app::{App, AppSettings};
 pub use fmt::Format;
+pub use errors::{ClapError, ClapErrorType};
 
 #[macro_use]
 mod macros;
@@ -680,3 +681,5 @@ mod app;
 mod args;
 mod usageparser;
 mod fmt;
+mod suggestions;
+mod errors;

src/suggestions.rs

@@ -1,6 +1,8 @@
 #[cfg(feature = "suggestions")]
 use strsim;
 
+use fmt::Format;
+
 /// Produces a string from a given list of possible values which is similar to
 /// the passed in value `v` with a certain confidence.
 /// Thus in a list of possible values like ["foo", "bar"], the value "fop" will yield
@@ -34,6 +36,34 @@ pub fn did_you_mean<'a, T, I>(_: &str, _: I) -> Option<&'a str>
     None
 }
 
+/// Returns a suffix that can be empty, or is the standard 'did you mean phrase
+#[cfg_attr(feature = "lints", allow(needless_lifetimes))]
+pub fn did_you_mean_suffix<'z, T, I>(arg: &str,
+                                 values: I,
+                                 style: DidYouMeanMessageStyle)
+                                 -> (String, Option<&'z str>)
+    where T: AsRef<str> + 'z,
+          I: IntoIterator<Item = &'z T>
+{
+    match did_you_mean(arg, values) {
+        Some(candidate) => {
+            let mut suffix = "\n\tDid you mean ".to_owned();
+            match style {
+                DidYouMeanMessageStyle::LongFlag =>
+                    suffix.push_str(&*format!("{}", Format::Good("--"))),
+                DidYouMeanMessageStyle::EnumValue => suffix.push('\''),
+            }
+            suffix.push_str(&Format::Good(candidate).to_string()[..]);
+            if let DidYouMeanMessageStyle::EnumValue = style {
+                suffix.push('\'');
+            }
+            suffix.push_str(" ?");
+            (suffix, Some(candidate))
+        }
+        None => (String::new(), None),
+    }
+}
+
 /// A helper to determine message formatting
 pub enum DidYouMeanMessageStyle {
     /// Suggested value is a long flag