Merge rust-bitcoin/rust-bitcoin#1623: Improve string parsing

090dad770f Improve string parsing (Tobin C. Harding)

Pull request description:

  Currently we implement string parsing for height/time from the `absolute` module but not the `relative` module.

  Improve the macros used to implement string parsing and use the new versions to implement string parsing for the height and time types in `relative`.

  Done while reviewing data structures in relation to `serde`.

ACKs for top commit:
  apoelstra:
    ACK 090dad770f
  Kixunil:
    ACK 090dad770f

Tree-SHA512: bfa88efbaf5dc35755eb46df373a08e223f112860e8a65f58db9fdd77e2c01dc9377da735b33ef58940004fe5fe11690ac09be19591fded2c9fd04cd7d2bdf73

bitcoin/src/blockdata/fee_rate.rs

@@ -2,6 +2,8 @@
 
 use core::fmt;
 use core::ops::{Mul, Div};
+
+use crate::prelude::*;
 use crate::Amount;
 use super::Weight;
 
@@ -133,4 +135,4 @@ impl Div<Weight> for Amount {
     }
 }
 
-crate::parse::impl_parse_str_through_int!(FeeRate);
+crate::parse::impl_parse_str_from_int_infallible!(FeeRate, u64, from_sat_per_kwu);

bitcoin/src/blockdata/locktime/absolute.rs

@@ -9,8 +9,6 @@
 
 use core::{mem, fmt};
 use core::cmp::{PartialOrd, Ordering};
-use core::convert::TryFrom;
-use core::str::FromStr;
 
 use bitcoin_internals::write_err;
 
@@ -20,8 +18,8 @@ use mutagen::mutate;
 use crate::consensus::encode::{self, Decodable, Encodable};
 use crate::error::ParseIntError;
 use crate::io::{self, Read, Write};
+use crate::parse::{impl_parse_str_from_int_infallible, impl_parse_str_from_int_fallible};
 use crate::prelude::*;
-use crate::parse::{self, impl_parse_str_through_int};
 use crate::string::FromHexStr;
 
 #[cfg(doc)]
@@ -276,7 +274,7 @@ impl LockTime {
     }
 }
 
-impl_parse_str_through_int!(LockTime, from_consensus);
+impl_parse_str_from_int_infallible!(LockTime, u32, from_consensus);
 
 impl From<Height> for LockTime {
     #[inline]
@@ -451,6 +449,8 @@ impl Height {
     }
 }
 
+impl_parse_str_from_int_fallible!(Height, u32, from_consensus, Error);
+
 impl fmt::Display for Height {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         fmt::Display::fmt(&self.0, f)
@@ -467,37 +467,6 @@ impl FromHexStr for Height {
     }
 }
 
-
-impl FromStr for Height {
-    type Err = Error;
-
-    #[inline]
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
-        let n = parse::int(s)?;
-        Height::from_consensus(n)
-    }
-}
-
-impl TryFrom<&str> for Height {
-    type Error = Error;
-
-    #[inline]
-    fn try_from(s: &str) -> Result<Self, Self::Error> {
-        let n = parse::int(s)?;
-        Height::from_consensus(n)
-    }
-}
-
-impl TryFrom<String> for Height {
-    type Error = Error;
-
-    #[inline]
-    fn try_from(s: String) -> Result<Self, Self::Error> {
-        let n = parse::int(s)?;
-        Height::from_consensus(n)
-    }
-}
-
 /// A UNIX timestamp, seconds since epoch, guaranteed to always contain a valid time value.
 ///
 /// Note that there is no manipulation of the inner value during construction or when using
@@ -564,6 +533,8 @@ impl Time {
     }
 }
 
+impl_parse_str_from_int_fallible!(Time, u32, from_consensus, Error);
+
 impl fmt::Display for Time {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         fmt::Display::fmt(&self.0, f)
@@ -580,36 +551,6 @@ impl FromHexStr for Time {
     }
 }
 
-impl FromStr for Time {
-    type Err = Error;
-
-    #[inline]
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
-        let n = parse::int(s)?;
-        Time::from_consensus(n)
-    }
-}
-
-impl TryFrom<&str> for Time {
-    type Error = Error;
-
-    #[inline]
-    fn try_from(s: &str) -> Result<Self, Self::Error> {
-        let n = parse::int(s)?;
-        Time::from_consensus(n)
-    }
-}
-
-impl TryFrom<String> for Time {
-    type Error = Error;
-
-    #[inline]
-    fn try_from(s: String) -> Result<Self, Self::Error> {
-        let n = parse::int(s)?;
-        Time::from_consensus(n)
-    }
-}
-
 /// Returns true if `n` is a block height i.e., less than 500,000,000.
 fn is_block_height(n: u32) -> bool {
     n < LOCK_TIME_THRESHOLD

bitcoin/src/blockdata/locktime/relative.rs

@@ -13,6 +13,9 @@ use core::convert::TryFrom;
 #[cfg(all(test, mutate))]
 use mutagen::mutate;
 
+use crate::parse::impl_parse_str_from_int_infallible;
+use crate::prelude::*;
+
 #[cfg(doc)]
 use crate::relative;
 
@@ -236,6 +239,8 @@ impl From<u16> for Height {
     }
 }
 
+impl_parse_str_from_int_infallible!(Height, u16, from);
+
 impl fmt::Display for Height {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         fmt::Display::fmt(&self.0, f)
@@ -300,6 +305,8 @@ impl Time {
     }
 }
 
+impl_parse_str_from_int_infallible!(Time, u16, from_512_second_intervals);
+
 impl fmt::Display for Time {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         fmt::Display::fmt(&self.0, f)

bitcoin/src/blockdata/transaction.rs

@@ -34,7 +34,7 @@ use crate::crypto::sighash::LegacySighash;
 use crate::hash_types::{Txid, Wtxid};
 use crate::VarInt;
 use crate::internal_macros::impl_consensus_encoding;
-use crate::parse::impl_parse_str_through_int;
+use crate::parse::impl_parse_str_from_int_infallible;
 use super::Weight;
 
 #[cfg(doc)]
@@ -500,7 +500,7 @@ impl fmt::UpperHex for Sequence {
     }
 }
 
-impl_parse_str_through_int!(Sequence);
+impl_parse_str_from_int_infallible!(Sequence, u32, from_consensus);
 
 /// Bitcoin transaction output.
 ///

bitcoin/src/blockdata/weight.rs

@@ -3,6 +3,8 @@
 use core::fmt;
 use core::ops::{Add, AddAssign, Sub, SubAssign, Mul, MulAssign, Div, DivAssign};
 
+use crate::prelude::*;
+
 /// Represents block weight - the weight of a transaction or block.
 ///
 /// This is an integer newtype representing weigth in `wu`. It provides protection against mixing
@@ -195,4 +197,4 @@ impl<'a> core::iter::Sum<&'a Weight> for Weight {
     }
 }
 
-crate::parse::impl_parse_str_through_int!(Weight);
+crate::parse::impl_parse_str_from_int_infallible!(Weight, u64, from_wu);

bitcoin/src/parse.rs

@@ -95,37 +95,78 @@ pub(crate) fn hex_u32<S: AsRef<str> + Into<String>>(s: S) -> Result<u32, ParseIn
 
 impl_std_error!(ParseIntError, source);
 
-/// Implements `TryFrom<$from> for $to` using `parse::int`, mapping the output using `fn`
-macro_rules! impl_tryfrom_str_through_int_single {
-    ($($from:ty, $to:ident $(, $fn:ident)?);*) => {
+/// Implements `TryFrom<$from> for $to` using `parse::int`, mapping the output using infallible
+/// conversion function `fn`.
+macro_rules! impl_tryfrom_str_from_int_infallible {
+    ($($from:ty, $to:ident, $inner:ident, $fn:ident);*) => {
         $(
         impl core::convert::TryFrom<$from> for $to {
             type Error = $crate::error::ParseIntError;
 
             fn try_from(s: $from) -> Result<Self, Self::Error> {
-                $crate::parse::int(s).map($to $(:: $fn)?)
+                $crate::parse::int::<$inner, $from>(s).map($to::$fn)
             }
         }
         )*
     }
 }
-pub(crate) use impl_tryfrom_str_through_int_single;
+pub(crate) use impl_tryfrom_str_from_int_infallible;
 
-/// Implements `FromStr` and `TryFrom<{&str, String, Box<str>}> for $to` using `parse::int`, mapping the output using `fn`
+/// Implements `FromStr` and `TryFrom<{&str, String, Box<str>}> for $to` using `parse::int`, mapping
+/// the output using infallible conversion function `fn`.
 ///
 /// The `Error` type is `ParseIntError`
-macro_rules! impl_parse_str_through_int {
-    ($to:ident $(, $fn:ident)?) => {
-        $crate::parse::impl_tryfrom_str_through_int_single!(&str, $to $(, $fn)?; alloc::string::String, $to $(, $fn)?; alloc::boxed::Box<str>, $to $(, $fn)?);
+macro_rules! impl_parse_str_from_int_infallible {
+    ($to:ident, $inner:ident, $fn:ident) => {
+        $crate::parse::impl_tryfrom_str_from_int_infallible!(&str, $to, $inner, $fn; String, $to, $inner, $fn; Box<str>, $to, $inner, $fn);
 
         impl core::str::FromStr for $to {
             type Err = $crate::error::ParseIntError;
 
             fn from_str(s: &str) -> Result<Self, Self::Err> {
-                $crate::parse::int(s).map($to $(:: $fn)?)
+                $crate::parse::int::<$inner, &str>(s).map($to::$fn)
             }
         }
 
     }
 }
-pub(crate) use impl_parse_str_through_int;
+pub(crate) use impl_parse_str_from_int_infallible;
+
+/// Implements `TryFrom<$from> for $to` using `parse::int`, mapping the output using fallible
+/// conversion function `fn`.
+macro_rules! impl_tryfrom_str_from_int_fallible {
+    ($($from:ty, $to:ident, $inner:ident, $fn:ident, $err:ident);*) => {
+        $(
+        impl core::convert::TryFrom<$from> for $to {
+            type Error = $err;
+
+            fn try_from(s: $from) -> Result<Self, Self::Error> {
+                let u = $crate::parse::int::<$inner, $from>(s)?;
+                $to::$fn(u)
+            }
+        }
+        )*
+    }
+}
+pub(crate) use impl_tryfrom_str_from_int_fallible;
+
+/// Implements `FromStr` and `TryFrom<{&str, String, Box<str>}> for $to` using `parse::int`, mapping
+/// the output using fallible conversion function `fn`.
+///
+/// The `Error` type is `ParseIntError`
+macro_rules! impl_parse_str_from_int_fallible {
+    ($to:ident, $inner:ident, $fn:ident, $err:ident) => {
+        $crate::parse::impl_tryfrom_str_from_int_fallible!(&str, $to, $inner, $fn, $err; String, $to, $inner, $fn, $err; Box<str>, $to, $inner, $fn, $err);
+
+        impl core::str::FromStr for $to {
+            type Err = $err;
+
+            fn from_str(s: &str) -> Result<Self, Self::Err> {
+                let u = $crate::parse::int::<$inner, &str>(s)?;
+                $to::$fn(u)
+            }
+        }
+
+    }
+}
+pub(crate) use impl_parse_str_from_int_fallible;