Refactoring for a more convenient BigInt api

justfile

@@ -10,8 +10,8 @@ coverage:
 # Remove generated files
 clean:
 	cargo clean
-	rm cobertura.xml
-	rm coverage.html
+	rm -f cobertura.xml
+	rm -f coverage.html
 
 # Check code style
 lint:

src/bigint.rs

@@ -13,7 +13,7 @@ use core::convert::TryInto;
 use core::ops::{
     Add, AddAssign, Div, DivAssign, Mul, MulAssign, Neg, Not, Rem, RemAssign, Sub, SubAssign,
 };
-use core::usize;
+use core::prelude::v1::*;
 #[cfg(feature = "std")]
 use std::prelude::v1::*;
 
@@ -28,10 +28,10 @@ pub struct BigInt {
 #[macro_export]
 macro_rules! big_int {
     ($w:literal) => {
-        $crate::bigint::BigInt::from($w)
+        $crate::bigint::BigInt::new($w)
     };
     (- $x:literal) => {
-        $crate::bigint::BigInt::from(-$x)
+        $crate::bigint::BigInt::new(-$x)
     };
 }
 
@@ -55,25 +55,26 @@ impl From<usize> for BigInt {
 
 impl From<&str> for BigInt {
     fn from(s: &str) -> Self {
-        Self::from_str_radix(s, 10)
+        Self::from_str(s, 10)
     }
 }
 
 impl From<String> for BigInt {
     fn from(s: String) -> Self {
-        Self::from_str_radix(&s, 10)
+        Self::from_str(&s, 10)
     }
 }
 
 impl BigInt {
     /// Create a new Bigint, of value 0
     ///
-    /// The various `From` implementations are more useful in most cases
+    /// In most cases, you probably want to use [new](`BigInt::new`) instead
     #[must_use]
     pub fn zero() -> Self {
         Self::default()
     }
 
+    /// Create a new `BigInt` from an existing Rust primitive type
     pub fn new(initial: impl Into<BigInt>) -> Self {
         initial.into()
     }
@@ -130,7 +131,7 @@ impl BigInt {
 
     /// Convert a `&str` or a `String` representing a number in the specified radix to a Bigint.
     ///
-    /// For radix 10, use the `from` associated function instead.
+    /// For radix 10, use the `new` or `from` associated function instead.
     ///
     /// Radix must be between 1 and 36, inclusive, with radix higher
     /// than 11 represented by A-Z
@@ -141,7 +142,7 @@ impl BigInt {
     /// # Panics
     /// * If radix is not between 1 and 36 inclusive
     /// * Some branches are not yet implemented
-    pub fn from_str_radix<T: ToString + ?Sized>(s: &T, radix: usize) -> BigInt {
+    pub fn from_str<T: ToString + ?Sized>(s: &T, radix: usize) -> BigInt {
         // Two lines due to borrow checker complaints
         let input = s.to_string().to_ascii_uppercase();
         let input = input.trim();
@@ -162,12 +163,12 @@ impl BigInt {
                 }
             }
 
-            return BigInt::from(raw_digits.len());
+            return BigInt::new(raw_digits.len());
         }
 
         // If the number fits in a usize, try the easy way
         if let Ok(easy_res) = usize::from_str_radix(input, radix.try_into().unwrap()) {
-            return BigInt::from(easy_res);
+            return BigInt::new(easy_res);
         }
 
         // TODO: consider parsing out the error, to tell if the
@@ -289,7 +290,7 @@ impl Add for BigInt {
             if overflowed {
                 out.inner.push(res + carry);
                 carry = 1;
-            } else if res < core::usize::MAX {
+            } else if res < usize::MAX {
                 out.inner.push(res + carry);
                 carry = 0;
             } else {
@@ -339,7 +340,7 @@ impl Sub for BigInt {
                 // In base ten, this would be like:
                 // 15 - 8 = (9 - 8) + (5 + 1)
                 let rem = (a + 1) - borrow;
-                let res = (core::usize::MAX - b) + rem;
+                let res = (usize::MAX - b) + rem;
                 out.inner.push(res);
 
                 borrow = 1;
@@ -527,8 +528,7 @@ macro_rules! impl_from_larger {
             impl From<$s> for BigInt {
                 /// Create a `BigInt` from a signed integer primitive
                 fn from(n: $s) -> Self {
-                    use core::usize::MAX;
-                    let target_radix: $s = (MAX as $s) + 1;
+                    let target_radix: $s = (usize::MAX as $s) + 1;
                     let sign = if n < 0 { Sign::Negative } else { Sign::Positive };
                     let n = n.abs();
 
@@ -562,8 +562,7 @@ macro_rules! impl_from_larger {
             impl From<$u> for BigInt {
                 /// Create a `BigInt` from an unsigned integer primitive
                 fn from(n: $u) -> Self {
-                    use core::usize::MAX;
-                    let target_radix: $u = (MAX as $u) + 1;
+                    let target_radix: $u = (usize::MAX as $u) + 1;
 
                     let mut quotient = n / target_radix;
                     let mut rem = n % target_radix;
@@ -601,28 +600,28 @@ macro_rules! impl_ord_literal {
             impl PartialEq<$prim> for BigInt {
                 #[must_use]
                 fn eq(&self, other: &$prim) -> bool {
-                    self == &BigInt::from(*other)
+                    self == &BigInt::new(*other)
                 }
             }
 
             impl PartialEq<BigInt> for $prim {
                 #[must_use]
                 fn eq(&self, other: &BigInt) -> bool {
-                    &BigInt::from(*self) == other
+                    &BigInt::new(*self) == other
                 }
             }
 
             impl PartialOrd<$prim> for BigInt {
                 #[must_use]
                 fn partial_cmp(&self, other: &$prim) -> Option<Ordering> {
-                    self.partial_cmp(&BigInt::from(*other))
+                    self.partial_cmp(&BigInt::new(*other))
                 }
             }
 
             impl PartialOrd<BigInt> for $prim {
                 #[must_use]
                 fn partial_cmp(&self, other: &BigInt) -> Option<Ordering> {
-                    (&BigInt::from(*self)).partial_cmp(other)
+                    (&BigInt::new(*self)).partial_cmp(other)
                 }
             }
         )+
@@ -647,23 +646,23 @@ impl_ord_literal!(i8, u8, i16, u16, i32, u32, i64, u64, i128, u128);
 mod tests {
     use super::*;
 
-    const RADIX: u128 = core::usize::MAX as u128 + 1;
-    const I_RADIX: i128 = core::usize::MAX as i128 + 1;
+    const RADIX: u128 = usize::MAX as u128 + 1;
+    const I_RADIX: i128 = usize::MAX as i128 + 1;
 
     #[test]
     fn sanity_checks() {
-        let int = BigInt::from(45u8);
+        let int = BigInt::new(45u8);
         assert_eq!(int.inner[0], 45usize)
     }
 
     #[test]
     fn test_macro() {
         let a = big_int!(75);
-        let b = BigInt::from(75);
+        let b = BigInt::new(75);
         assert_eq!(a, b);
 
         let a = big_int!(-75);
-        let b = BigInt::from(-75);
+        let b = BigInt::new(-75);
         assert_eq!(a, b);
     }
 
@@ -676,7 +675,7 @@ mod tests {
 
         lots_of_leading.trim_zeros();
 
-        assert_eq!(BigInt::from(1), lots_of_leading);
+        assert_eq!(BigInt::new(1), lots_of_leading);
     }
 
     #[test]
@@ -685,32 +684,32 @@ mod tests {
         // so the sum should be
         // [MAX -1, 1]
         // Compare base 10: 9 + 9 = 18
-        let a = BigInt::from(core::usize::MAX);
-        let b = BigInt::from(core::usize::MAX);
+        let a = BigInt::new(usize::MAX);
+        let b = BigInt::new(usize::MAX);
 
         let sum = a + b;
 
         assert_eq!(
             sum.inner[0],
-            core::usize::MAX - 1,
+            usize::MAX - 1,
             "least significant place should be MAX - 1"
         );
         assert_eq!(sum.inner[1], 1usize, "most significant place should be 1");
 
-        let a = BigInt::from(core::usize::MAX);
-        let b = BigInt::from(1usize);
+        let a = BigInt::new(usize::MAX);
+        let b = BigInt::new(1usize);
         let sum = a + b;
         assert_eq!(sum.inner[0], 0_usize);
         assert_eq!(sum.inner[1], 1usize);
 
-        let a = BigInt::from(10);
-        let b = -BigInt::from(5);
+        let a = BigInt::new(10);
+        let b = -BigInt::new(5);
         let sum = a + b;
         assert_eq!(sum.inner[0], 5usize);
         assert_eq!(sum.sign, Positive);
 
-        let a = -BigInt::from(5);
-        let b = BigInt::from(10);
+        let a = -BigInt::new(5);
+        let b = BigInt::new(10);
         let sum = a + b;
         assert_eq!(sum.inner[0], 5usize);
         assert_eq!(sum.sign, Positive);
@@ -718,14 +717,14 @@ mod tests {
 
     #[test]
     fn test_add_assign() {
-        let mut a = BigInt::from(core::usize::MAX);
-        let b = BigInt::from(core::usize::MAX);
+        let mut a = BigInt::new(usize::MAX);
+        let b = BigInt::new(usize::MAX);
 
         a += b;
 
         assert_eq!(
             a.inner[0],
-            core::usize::MAX - 1,
+            usize::MAX - 1,
             "least significant place should be MAX - 1"
         );
         assert_eq!(a.inner[1], 1usize, "most significant place should be 1");
@@ -733,24 +732,24 @@ mod tests {
 
     #[test]
     fn test_sub() {
-        let a = BigInt::from(core::usize::MAX);
-        let b = BigInt::from(core::u16::MAX);
+        let a = BigInt::new(usize::MAX);
+        let b = BigInt::new(core::u16::MAX);
 
         let diff = a - b;
         assert_eq!(
             diff.clone().inner[0],
-            core::usize::MAX - core::u16::MAX as usize
+            usize::MAX - core::u16::MAX as usize
         );
         assert_eq!(diff.inner.len(), 1);
 
-        let a = BigInt::from(5);
-        let b = -BigInt::from(3);
+        let a = BigInt::new(5);
+        let b = -BigInt::new(3);
         let diff = a - b;
         assert_eq!(diff.sign, Positive);
         assert_eq!(diff.inner[0], 8usize);
 
-        let a = -BigInt::from(5);
-        let b = BigInt::from(3);
+        let a = -BigInt::new(5);
+        let b = BigInt::new(3);
         let diff = a - b;
         assert_eq!(diff.sign, Negative);
         assert_eq!(diff.inner[0], 8usize);
@@ -763,10 +762,10 @@ mod tests {
             sign: Positive,
         };
 
-        let b = BigInt::from(2);
+        let b = BigInt::new(2);
         let diff = a - b;
         assert_eq!(diff.clone().inner.len(), 1, "{:#?}", diff.clone());
-        assert_eq!(diff.inner[0], core::usize::MAX - 1);
+        assert_eq!(diff.inner[0], usize::MAX - 1);
     }
 
     #[test]
@@ -775,7 +774,7 @@ mod tests {
             inner: vec![1, 0, 1],
             sign: Positive,
         };
-        let b = BigInt::from(2);
+        let b = BigInt::new(2);
 
         a -= b;
 
@@ -784,8 +783,8 @@ mod tests {
 
     #[test]
     fn test_mul() {
-        let a = BigInt::from(65536);
-        let b = BigInt::from(4);
+        let a = BigInt::new(65536);
+        let b = BigInt::new(4);
 
         let product = a * b;
         assert_eq!(product.inner[0], 65536usize * 4);
@@ -793,26 +792,26 @@ mod tests {
 
     #[test]
     fn test_mul_signs() {
-        let a = BigInt::from(2);
-        let b = BigInt::from(-2);
+        let a = BigInt::new(2);
+        let b = BigInt::new(-2);
         let product = a * b;
         assert_eq!(product.inner[0], 4usize);
         assert_eq!(product.sign, Negative);
 
-        let a = -BigInt::from(2);
-        let b = BigInt::from(2);
+        let a = -BigInt::new(2);
+        let b = BigInt::new(2);
         let product = a * b;
         assert_eq!(product.inner[0], 4usize);
         assert_eq!(product.sign, Negative);
 
-        let a = BigInt::from(-2);
-        let b = BigInt::from(-2);
+        let a = BigInt::new(-2);
+        let b = BigInt::new(-2);
         let product = a * b;
         assert_eq!(product.inner[0], 4usize);
         assert_eq!(product.sign, Positive);
 
-        let a = BigInt::from(2);
-        let b = BigInt::from(2);
+        let a = BigInt::new(2);
+        let b = BigInt::new(2);
         let product = a * b;
         assert_eq!(product.inner[0], 4usize);
         assert_eq!(product.sign, Positive);
@@ -821,8 +820,8 @@ mod tests {
     #[test]
     #[should_panic]
     fn test_mul_overflow() {
-        let a = BigInt::from(core::usize::MAX);
-        let b = BigInt::from(5);
+        let a = BigInt::new(usize::MAX);
+        let b = BigInt::new(5);
 
         let _product = a * b;
     }
@@ -830,8 +829,8 @@ mod tests {
     #[test]
     #[should_panic]
     fn test_mul_assign_overflow() {
-        let mut a = BigInt::from(core::usize::MAX);
-        let b = BigInt::from(5);
+        let mut a = BigInt::new(usize::MAX);
+        let b = BigInt::new(5);
 
         a *= b;
     }
@@ -839,8 +838,8 @@ mod tests {
     #[test]
     #[should_panic]
     fn test_div() {
-        let a = BigInt::from(128);
-        let b = BigInt::from(32);
+        let a = BigInt::new(128);
+        let b = BigInt::new(32);
 
         let _quotient = a / b;
     }
@@ -848,8 +847,8 @@ mod tests {
     #[test]
     #[should_panic]
     fn test_div_assign() {
-        let mut a = BigInt::from(128);
-        let b = BigInt::from(32);
+        let mut a = BigInt::new(128);
+        let b = BigInt::new(32);
 
         a /= b;
     }
@@ -857,8 +856,8 @@ mod tests {
     #[test]
     #[should_panic]
     fn test_rem() {
-        let a = BigInt::from(5);
-        let b = BigInt::from(2);
+        let a = BigInt::new(5);
+        let b = BigInt::new(2);
 
         let _rem = a % b;
     }
@@ -866,8 +865,8 @@ mod tests {
     #[test]
     #[should_panic]
     fn test_rem_assign() {
-        let mut a = BigInt::from(5);
-        let b = BigInt::from(2);
+        let mut a = BigInt::new(5);
+        let b = BigInt::new(2);
 
         a %= b;
     }
@@ -888,16 +887,16 @@ mod tests {
 
     #[test]
     fn test_not() {
-        let a = BigInt::from(0_u8);
+        let a = BigInt::new(0_u8);
         let b = !a;
 
-        assert_eq!(b.inner[0], core::usize::MAX);
+        assert_eq!(b.inner[0], usize::MAX);
     }
 
     #[test]
     fn test_partial_eq() {
         let a = 12345_u16;
-        let b = BigInt::from(a);
+        let b = BigInt::new(a);
 
         assert!(a.eq(&b));
         assert!(b.eq(&a));
@@ -906,7 +905,7 @@ mod tests {
     #[test]
     fn test_partial_ord() {
         let a = 12345_u32;
-        let b = BigInt::from(a);
+        let b = BigInt::new(a);
         let c = 3_u8;
 
         assert_eq!(a.partial_cmp(&b), Some(Ordering::Equal));
@@ -922,16 +921,16 @@ mod tests {
     #[test]
     fn test_from() {
         // Signed numbers
-        assert_eq!(-BigInt::from(2), BigInt::from(-2));
+        assert_eq!(-BigInt::new(2), BigInt::new(-2));
 
         // Larger than usize
-        assert_eq!(BigInt::from(45_u128), BigInt::from(45_usize));
+        assert_eq!(BigInt::new(45_u128), BigInt::new(45_usize));
     }
 
     #[test]
     fn test_from_large_unsigned() {
         let big_num: u128 = 9 * RADIX + 8;
-        let res = BigInt::from(big_num);
+        let res = BigInt::new(big_num);
 
         assert_eq!(res.sign, Sign::Positive, "{:#?}", res);
         assert_eq!(res.inner[0], 8_usize, "{:#?}", res);
@@ -941,7 +940,7 @@ mod tests {
     #[test]
     fn test_from_large_signed() {
         let big_num: i128 = 2 * I_RADIX + 3;
-        let res = BigInt::from(-big_num);
+        let res = BigInt::new(-big_num);
 
         assert_eq!(res.sign, Sign::Negative, "{:#?}", res);
         assert_eq!(res.inner[0], 3_usize, "{:#?}", res);
@@ -952,13 +951,13 @@ mod tests {
     #[should_panic]
     fn test_from_str_large() {
         let str = "ZYXWVUTSRQPONMLKJIHGFEDCBA987654321";
-        let _ = BigInt::from(str);
+        let _ = BigInt::new(str);
     }
 
     #[test]
     fn test_from_str_small() {
         let str = "012345";
-        let num = BigInt::from(str);
+        let num = BigInt::new(str);
         assert_eq!(num.inner[0], 12345_usize);
     }
 
@@ -966,20 +965,20 @@ mod tests {
     #[should_panic]
     fn test_from_string_large() {
         let str = String::from("ZYXWVUTSRQPONMLKJIHGFEDCBA987654321");
-        let _ = BigInt::from(str);
+        let _ = BigInt::new(str);
     }
 
     #[test]
     fn test_from_string_small() {
         let str = String::from("012345");
-        let num = BigInt::from(str);
+        let num = BigInt::new(str);
         assert_eq!(num.inner[0], 12345_usize);
     }
 
     #[test]
     fn test_from_str_radix_1() {
         let s = "1".repeat(32);
-        let num = BigInt::from_str_radix(&s, 1);
+        let num = BigInt::from_str(&s, 1);
         assert_eq!(num.inner[0], 32_usize);
     }
 
@@ -989,25 +988,25 @@ mod tests {
         let zeroes = "0".repeat(24);
         let s = ones + &zeroes;
 
-        let num = BigInt::from_str_radix(&s, 1);
+        let num = BigInt::from_str(&s, 1);
         assert_eq!(num.inner[0], 32_usize);
     }
 
     #[test]
     #[should_panic]
     fn test_from_str_radix_invalid() {
-        let _ = BigInt::from_str_radix("foobar0", 50);
+        let _ = BigInt::from_str("foobar0", 50);
     }
 
     #[test]
     #[should_panic]
     fn test_from_str_radix_large() {
-        let _ = BigInt::from_str_radix("ZYXWVUTSRQPONMLKJIHGFEDCBA987654321", 36);
+        let _ = BigInt::from_str("ZYXWVUTSRQPONMLKJIHGFEDCBA987654321", 36);
     }
 
     #[test]
     fn test_from_str_radix_small() {
-        let num = BigInt::from_str_radix("FEDCBA", 16);
+        let num = BigInt::from_str("FEDCBA", 16);
         assert!(num.inner[0] > 0, "Number is not greater than 0");
         assert!(num.inner[0] < usize::MAX, "Result is larger than usize");
         assert_eq!(num.inner[0], 0xFEDCBA_usize);
@@ -1015,7 +1014,7 @@ mod tests {
 
     #[test]
     fn test_from_str_radix_lowercase() {
-        let num = BigInt::from_str_radix("fedcba", 16);
+        let num = BigInt::from_str("fedcba", 16);
         assert_eq!(num.inner[0], 0xFEDCBA_usize);
     }
 }