style: add config for symlink arrow

src/display.rs

@@ -286,7 +286,7 @@ fn get_output<'a>(
                         ANSIStrings(&[
                             meta.name.render(colors, icons, &display_option),
                             meta.indicator.render(&flags),
-                            meta.symlink.render(colors),
+                            meta.symlink.render(colors, &flags.styles),
                         ])
                         .to_string()
                     };

src/flags.rs

@@ -33,6 +33,7 @@ pub use sorting::SortColumn;
 pub use sorting::SortOrder;
 pub use sorting::Sorting;
 pub use symlinks::NoSymlink;
+pub use symlinks::SymlinkArrow;
 pub use total_size::TotalSize;
 
 use crate::config_file::Config;
@@ -59,6 +60,13 @@ pub struct Flags {
     pub size: SizeFlag,
     pub sorting: Sorting,
     pub total_size: TotalSize,
+    pub styles: Styles,
+}
+
+/// A struct to hold the style flags for the application.
+#[derive(Clone, Debug, Default)]
+pub struct Styles {
+    pub symlink_arrow: SymlinkArrow,
 }
 
 impl Flags {
@@ -84,6 +92,9 @@ impl Flags {
             recursion: Recursion::configure_from(matches, config)?,
             sorting: Sorting::configure_from(matches, config),
             total_size: TotalSize::configure_from(matches, config),
+            styles: Styles {
+                symlink_arrow: SymlinkArrow::configure_from(matches, config),
+            },
         })
     }
 }

src/flags/symlinks.rs

@@ -46,6 +46,53 @@ impl Configurable<Self> for NoSymlink {
     }
 }
 
+/// The flag showing how to display symbolic arrow.
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct SymlinkArrow(String);
+
+impl Configurable<Self> for SymlinkArrow {
+    /// `SymlinkArrow` can not be configured by [ArgMatches]
+    ///
+    /// Return `None`
+    fn from_arg_matches(_: &ArgMatches) -> Option<Self> {
+        None
+    }
+    /// Get a potential `SymlinkArrow` value from a [Config].
+    ///
+    /// If the Config's [Yaml] contains the [String](Yaml::String) value pointed to by
+    /// "symlink-arrow", this returns its value as the value of the `SymlinkArrow`, in a [Some].
+    /// Otherwise this returns [None].
+    fn from_config(config: &Config) -> Option<Self> {
+        if let Some(yaml) = &config.yaml {
+            match &yaml["styles"]["symlink-arrow"] {
+                Yaml::BadValue => None,
+                Yaml::String(value) => Some(SymlinkArrow(value.to_string())),
+                _ => {
+                    config.print_wrong_type_warning("symlink-arrow", "string");
+                    None
+                }
+            }
+        } else {
+            None
+        }
+    }
+}
+
+/// The default value for the `SymlinkArrow` is `\u{21d2}(⇒)`
+impl Default for SymlinkArrow {
+    fn default() -> Self {
+        Self(String::from("\u{21d2}")) // ⇒
+    }
+}
+
+use std::fmt;
+impl fmt::Display for SymlinkArrow {
+    // This trait requires `fmt` with this exact signature.
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
+
 #[cfg(test)]
 mod test {
     use super::NoSymlink;
@@ -101,4 +148,16 @@ mod test {
             NoSymlink::from_config(&Config::with_yaml(yaml))
         );
     }
+
+    use super::SymlinkArrow;
+    #[test]
+    fn test_from_config_arrow_utf8() {
+        let yaml_string = "styles:
+  symlink-arrow: ↹";
+        let yaml = YamlLoader::load_from_str(yaml_string).unwrap()[0].clone();
+        assert_eq!(
+            Some(SymlinkArrow(String::from("\u{21B9}"))),
+            SymlinkArrow::from_config(&Config::with_yaml(yaml))
+        );
+    }
 }

src/meta/symlink.rs

@@ -1,4 +1,5 @@
 use crate::color::{ColoredString, Colors, Elem};
+use crate::flags::Styles;
 use ansi_term::{ANSIString, ANSIStrings};
 use std::fs::read_link;
 use std::path::Path;
@@ -51,7 +52,7 @@ impl SymLink {
         }
     }
 
-    pub fn render(&self, colors: &Colors) -> ColoredString {
+    pub fn render(&self, colors: &Colors, styles: &Styles) -> ColoredString {
         if let Some(target_string) = self.symlink_string() {
             let elem = if self.valid {
                 &Elem::SymLink
@@ -60,7 +61,7 @@ impl SymLink {
             };
 
             let strings: &[ColoredString] = &[
-                ColoredString::from(" \u{21d2} "), // ⇒
+                ColoredString::from(format!(" {} ", styles.symlink_arrow)), // ⇒ \u{21d2}
                 colors.colorize(target_string, elem),
             ];