Auto merge of #159 - anchovieshat:master, r=cuviper

Add Binary, Octal to BigUint. Add UpperHex, LowerHex, Binary, Octal to BigInt

Is the testing for these enough? Any suggestions to improve them?

src/bigint.rs

@@ -255,6 +255,18 @@ impl fmt::UpperHex for BigUint {
     }
 }
 
+impl fmt::Binary for BigUint {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.to_str_radix(2))
+    }
+}
+
+impl fmt::Octal for BigUint {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.to_str_radix(8))
+    }
+}
+
 impl FromStr for BigUint {
     type Err = ParseBigIntError;
 
@@ -1838,6 +1850,30 @@ impl fmt::Display for BigInt {
     }
 }
 
+impl fmt::Binary for BigInt {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.to_str_radix(2))
+    }
+}
+
+impl fmt::Octal for BigInt {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.to_str_radix(8))
+    }
+}
+
+impl fmt::LowerHex for BigInt {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.to_str_radix(16))
+    }
+}
+
+impl fmt::UpperHex for BigInt {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.to_str_radix(16).to_ascii_uppercase())
+    }
+}
+
 impl FromStr for BigInt {
     type Err = ParseBigIntError;
 
@@ -3741,6 +3777,24 @@ mod biguint_tests {
         assert_eq!(format!("{:X}", hello), "48656C6C6F20776F726C6421");
     }
 
+    #[test]
+    fn test_binary() {
+        let a = BigUint::parse_bytes(b"A", 16).unwrap();
+        let hello = BigUint::parse_bytes("224055342307539".as_bytes(), 10).unwrap();
+
+        assert_eq!(format!("{:b}", a), "1010");
+        assert_eq!(format!("{:b}", hello), "110010111100011011110011000101101001100011010011");
+    }
+
+    #[test]
+    fn test_octal() {
+        let a = BigUint::parse_bytes(b"A", 16).unwrap();
+        let hello = BigUint::parse_bytes("22405534230753963835153736737".as_bytes(), 10).unwrap();
+
+        assert_eq!(format!("{:o}", a), "12");
+        assert_eq!(format!("{:o}", hello), "22062554330674403566756233062041");
+    }
+
     #[test]
     fn test_factor() {
         fn factor(n: usize) -> BigUint {
@@ -4027,6 +4081,7 @@ mod bigint_tests {
         }
     }
 
+
     #[test]
     fn test_hash() {
         let a = BigInt::new(NoSign, vec!());
@@ -4704,6 +4759,42 @@ mod bigint_tests {
         let _y = x.to_string();
     }
 
+    #[test]
+    fn test_lower_hex() {
+        let a = BigInt::parse_bytes(b"A", 16).unwrap();
+        let hello = BigInt::parse_bytes("-22405534230753963835153736737".as_bytes(), 10).unwrap();
+
+        assert_eq!(format!("{:x}", a), "a");
+        assert_eq!(format!("{:x}", hello), "-48656c6c6f20776f726c6421");
+    }
+
+    #[test]
+    fn test_upper_hex() {
+        let a = BigInt::parse_bytes(b"A", 16).unwrap();
+        let hello = BigInt::parse_bytes("-22405534230753963835153736737".as_bytes(), 10).unwrap();
+
+        assert_eq!(format!("{:X}", a), "A");
+        assert_eq!(format!("{:X}", hello), "-48656C6C6F20776F726C6421");
+    }
+
+    #[test]
+    fn test_binary() {
+        let a = BigInt::parse_bytes(b"A", 16).unwrap();
+        let hello = BigInt::parse_bytes("-224055342307539".as_bytes(), 10).unwrap();
+
+        assert_eq!(format!("{:b}", a), "1010");
+        assert_eq!(format!("{:b}", hello), "-110010111100011011110011000101101001100011010011");
+    }
+
+    #[test]
+    fn test_octal() {
+        let a = BigInt::parse_bytes(b"A", 16).unwrap();
+        let hello = BigInt::parse_bytes("-22405534230753963835153736737".as_bytes(), 10).unwrap();
+
+        assert_eq!(format!("{:o}", a), "12");
+        assert_eq!(format!("{:o}", hello), "-22062554330674403566756233062041");
+    }
+
     #[test]
     fn test_neg() {
         assert!(-BigInt::new(Plus,  vec!(1, 1, 1)) ==