Support core::fmt::Display and alternative formats. (#2)

svartalf · Dec 29, 2019 · 0f0916a · 0f0916a
1 parent 16784c4
commit 0f0916a
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Showing 5 changed files with 83 additions and 54 deletions.
diff --git a/src/addr.rs b/src/addr.rs
@@ -1,8 +1,8 @@
 #[cfg(feature = "std")]
-use ::std::str::FromStr;
+use std::{fmt, str::FromStr};
 
 #[cfg(not(feature = "std"))]
-use core::str::FromStr;
+use core::{fmt, str::FromStr};
 
 use crate::{parser, MacAddr6, MacAddr8, ParseError};
 
@@ -101,3 +101,12 @@ impl From<[u8; 8]> for MacAddr {
         MacAddr::V8(MacAddr8::from(bytes))
     }
 }
+
+impl fmt::Display for MacAddr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            MacAddr::V6(v6) => fmt::Display::fmt(v6, f),
+            MacAddr::V8(v8) => fmt::Display::fmt(v8, f),
+        }
+    }
+}
diff --git a/src/addr6.rs b/src/addr6.rs
@@ -1,18 +1,15 @@
 #[cfg(feature = "std")]
-use ::std::str::FromStr;
+use std::{fmt, str::FromStr};
 
 #[cfg(not(feature = "std"))]
-use core::str::FromStr;
-
-#[cfg(feature = "serde")]
-use serde::{Deserialize, Serialize};
+use core::{fmt, str::FromStr};
 
 use crate::parser;
 
 /// MAC address in *EUI-48* format.
 #[repr(C)]
 #[derive(Debug, Default, Hash, Eq, PartialEq, Ord, PartialOrd, Copy, Clone)]
-#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct MacAddr6([u8; 6]);
 
 impl MacAddr6 {
@@ -200,24 +197,37 @@ impl AsMut<[u8]> for MacAddr6 {
     }
 }
 
-#[cfg(feature = "std")]
-mod std {
-    use std::fmt;
-
-    use super::MacAddr6;
-
-    impl fmt::Display for MacAddr6 {
-        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+/// `MacAddr6` can be displayed in different formats.
+///
+/// # Example
+///
+/// ```
+/// # use macaddr::MacAddr6;
+/// let addr = MacAddr6::new(0xab, 0x0d, 0xef, 0x12, 0x34, 0x56);
+///
+/// assert_eq!(&format!("{}",    addr), "AB:0D:EF:12:34:56");
+/// assert_eq!(&format!("{:-}",  addr), "AB-0D-EF-12-34-56");
+/// assert_eq!(&format!("{:#}",  addr), "AB0.DEF.123.456");
+/// ```
+impl fmt::Display for MacAddr6 {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        if f.sign_minus() {
+            f.write_fmt(format_args!(
+                "{:02X}-{:02X}-{:02X}-{:02X}-{:02X}-{:02X}",
+                self.0[0], self.0[1], self.0[2], self.0[3], self.0[4], self.0[5],
+            ))
+        } else if f.alternate() {
+            let p1 = u16::from(self.0[0]) * 16 + u16::from(self.0[1] / 16);
+            let p2 = u16::from(self.0[1] % 16) * 256 + u16::from(self.0[2]);
+            let p3 = u16::from(self.0[3]) * 16 + u16::from(self.0[4] / 16);
+            let p4 = u16::from(self.0[4] % 16) * 256 + u16::from(self.0[5]);
+
+            f.write_fmt(format_args!("{:03X}.{:03X}.{:03X}.{:03X}", p1, p2, p3, p4,))
+        } else {
             f.write_fmt(format_args!(
-                    // Canonical form
-                    "{:02X}-{:02X}-{:02X}-{:02X}-{:02X}-{:02X}",
-                    self.0[0],
-                    self.0[1],
-                    self.0[2],
-                    self.0[3],
-                    self.0[4],
-                    self.0[5],
-                ))
+                "{:02X}:{:02X}:{:02X}:{:02X}:{:02X}:{:02X}",
+                self.0[0], self.0[1], self.0[2], self.0[3], self.0[4], self.0[5],
+            ))
         }
     }
 }
diff --git a/src/addr8.rs b/src/addr8.rs
@@ -1,18 +1,15 @@
 #[cfg(feature = "std")]
-use ::std::str::FromStr;
+use std::{fmt, str::FromStr};
 
 #[cfg(not(feature = "std"))]
-use core::str::FromStr;
-
-#[cfg(feature = "serde")]
-use serde::{Deserialize, Serialize};
+use core::{fmt, str::FromStr};
 
 use crate::parser;
 
 /// MAC address in *EUI-64* format.
 #[repr(C)]
 #[derive(Debug, Default, Hash, Eq, PartialEq, Ord, PartialOrd, Copy, Clone)]
-#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct MacAddr8([u8; 8]);
 
 impl MacAddr8 {
@@ -200,26 +197,35 @@ impl AsMut<[u8]> for MacAddr8 {
     }
 }
 
-#[cfg(feature = "std")]
-mod std {
-    use std::fmt;
-
-    use super::MacAddr8;
-
-    impl fmt::Display for MacAddr8 {
-        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+/// `MacAddr8` can be displayed in different formats.
+///
+/// # Example
+///
+/// ```
+/// # use macaddr::MacAddr8;
+/// let addr = MacAddr8::new(0xab, 0x0d, 0xef, 0x12, 0x34, 0x56, 0x78, 0x9A);
+///
+/// assert_eq!(&format!("{}",    addr), "AB:0D:EF:12:34:56:78:9A");
+/// assert_eq!(&format!("{:-}",  addr), "AB-0D-EF-12-34-56-78-9A");
+/// assert_eq!(&format!("{:#}",  addr), "AB0D.EF12.3456.789A");
+/// ```
+impl fmt::Display for MacAddr8 {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        if f.sign_minus() {
+            f.write_fmt(format_args!(
+                "{:02X}-{:02X}-{:02X}-{:02X}-{:02X}-{:02X}-{:02X}-{:02X}",
+                self.0[0], self.0[1], self.0[2], self.0[3], self.0[4], self.0[5], self.0[6], self.0[7],
+            ))
+        } else if f.alternate() {
+            f.write_fmt(format_args!(
+                "{:02X}{:02X}.{:02X}{:02X}.{:02X}{:02X}.{:02X}{:02X}",
+                self.0[0], self.0[1], self.0[2], self.0[3], self.0[4], self.0[5], self.0[6], self.0[7],
+            ))
+        } else {
             f.write_fmt(format_args!(
-                    // Canonical form
-                    "{:02X}-{:02X}-{:02X}-{:02X}-{:02X}-{:02X}-{:02X}-{:02X}",
-                    self.0[0],
-                    self.0[1],
-                    self.0[2],
-                    self.0[3],
-                    self.0[4],
-                    self.0[5],
-                    self.0[6],
-                    self.0[7],
-                ))
+                "{:02X}:{:02X}:{:02X}:{:02X}:{:02X}:{:02X}:{:02X}:{:02X}",
+                self.0[0], self.0[1], self.0[2], self.0[3], self.0[4], self.0[5], self.0[6], self.0[7],
+            ))
         }
     }
 }
diff --git a/src/parser/mod.rs b/src/parser/mod.rs
@@ -1,7 +1,8 @@
 #[cfg(feature = "std")]
-use std::error::Error;
-#[cfg(feature = "std")]
-use std::fmt;
+use std::{error::Error, fmt};
+
+#[cfg(not(feature = "std"))]
+use core::fmt;
 
 use crate::{MacAddr, MacAddr6, MacAddr8};
 
@@ -31,7 +32,6 @@ pub enum ParseError {
     InvalidCharacter(char, usize),
 }
 
-#[cfg(feature = "std")]
 impl fmt::Display for ParseError {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match self {

diff --git a/src/parser/tests.rs b/src/parser/tests.rs
@@ -1,5 +1,9 @@
+#[cfg(feature = "std")]
 use std::str::FromStr;
 
+#[cfg(not(feature = "std"))]
+use core::str::FromStr;
+
 use assert_matches::assert_matches;
 
 use crate::{MacAddr, MacAddr6, MacAddr8};