From 39dcd647f23b3b626711981c3800e17057795a79 Mon Sep 17 00:00:00 2001
From: Hexa Dust <hxd@hexadust.net>
Date: Fri, 18 Jul 2025 21:19:30 +0100
Subject: [PATCH] optional ufmt::uDebug impl

---
 Cargo.lock  | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 Cargo.toml  |  4 ++++
 src/calc.rs | 18 +++++++++++++++
 src/lib.rs  | 18 +++++++++++++++
 4 files changed, 103 insertions(+)

diff --git a/Cargo.lock b/Cargo.lock
index 42484f5..a4ef948 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -20,6 +20,7 @@ version = "0.1.0"
 dependencies = [
  "arrayvec",
  "num-traits",
+ "ufmt",
 ]
 
 [[package]]
@@ -30,3 +31,65 @@ checksum = "071dfc062690e90b734c0b2273ce72ad0ffa95f0c74596bc250dcfd960262841"
 dependencies = [
  "autocfg",
 ]
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.95"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "02b3e5e68a3a1a02aad3ec490a98007cbc13c37cbe84a3cd7b8e406d76e7f778"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.40"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1885c039570dc00dcb4ff087a89e185fd56bae234ddc7f056a945bf36467248d"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "syn"
+version = "1.0.109"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72b64191b275b66ffe2469e8af2c1cfe3bafa67b529ead792a6d0160888b4237"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "ufmt"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1a64846ec02b57e9108d6469d98d1648782ad6bb150a95a9baac26900bbeab9d"
+dependencies = [
+ "ufmt-macros",
+ "ufmt-write",
+]
+
+[[package]]
+name = "ufmt-macros"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d337d3be617449165cb4633c8dece429afd83f84051024079f97ad32a9663716"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "ufmt-write"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e87a2ed6b42ec5e28cc3b94c09982969e9227600b2e3dcbc1db927a84c06bd69"
+
+[[package]]
+name = "unicode-ident"
+version = "1.0.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5a5f39404a5da50712a4c1eecf25e90dd62b613502b7e925fd4e4d19b5c96512"
diff --git a/Cargo.toml b/Cargo.toml
index cabf607..3bda35a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,6 +5,10 @@ edition = "2021"
 
 [dependencies]
 num-traits = { version = "0.2.19", default-features = false }
+ufmt = { version = "0.2.0", optional = true }
 
 [dev-dependencies]
 arrayvec = { version = "0.7.6", default-features = false }
+
+[features]
+ufmt = ["dep:ufmt"]
diff --git a/src/calc.rs b/src/calc.rs
index d224178..b80a724 100644
--- a/src/calc.rs
+++ b/src/calc.rs
@@ -1,10 +1,13 @@
 use core::{convert::Infallible, fmt::Display, marker::PhantomData};
 
 use num_traits::{float::FloatCore, PrimInt, Unsigned};
+#[cfg(feature = "ufmt")]
+use ufmt::derive::uDebug;
 
 use crate::{Decimal, DecimalError};
 
 #[derive(Debug)]
+#[cfg_attr(feature = "ufmt", derive(uDebug))]
 pub enum StackCalcError {
     StackOverflow,
     StackUnderflow,
@@ -28,6 +31,21 @@ pub struct StackCalc<F: FloatCore, const STACK: usize = 2, const DSIZE: usize =
     phantom: PhantomData<F>,
 }
 
+#[cfg(feature = "ufmt")]
+impl<F: FloatCore + ufmt::uDebug, const STACK: usize, const DSIZE: usize, EXP: ufmt::uDebug>
+    ufmt::uDebug for StackCalc<F, STACK, DSIZE, EXP>
+{
+    fn fmt<W>(&self, f: &mut ufmt::Formatter<'_, W>) -> Result<(), W::Error>
+    where
+        W: ufmt::uWrite + ?Sized,
+    {
+        f.debug_struct("StackCalc")?
+            .field("stack", &self.stack.as_slice())?
+            .field("index", &self.index)?
+            .finish()
+    }
+}
+
 impl<F: FloatCore, const STACK: usize, const DSIZE: usize, EXP: PrimInt> Default
     for StackCalc<F, STACK, DSIZE, EXP>
 {
diff --git a/src/lib.rs b/src/lib.rs
index de2e8c4..9d263bd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,8 +5,11 @@ pub mod calc;
 use core::fmt::Display;
 use num_traits::float::FloatCore;
 use num_traits::{one, zero, PrimInt, Unsigned};
+#[cfg(feature = "ufmt")]
+use ufmt::derive::uDebug;
 
 #[derive(Debug)]
+#[cfg_attr(feature = "ufmt", derive(uDebug))]
 pub enum DecimalError {
     ExponentOverflow,
     NotANumber,
@@ -29,6 +32,21 @@ pub struct Decimal<const SIZE: usize = 5, EXP = u16> {
     exponent: EXP,
 }
 
+#[cfg(feature = "ufmt")]
+impl<const SIZE: usize, EXP: ufmt::uDebug> ufmt::uDebug for Decimal<SIZE, EXP> {
+    fn fmt<W>(&self, f: &mut ufmt::Formatter<'_, W>) -> Result<(), W::Error>
+    where
+        W: ufmt::uWrite + ?Sized,
+    {
+        f.debug_struct("Decimal")?
+            .field("minus", &self.minus)?
+            .field("significant", &self.significant.as_slice())?
+            .field("minus_exponent", &self.minus_exponent)?
+            .field("exponent", &self.exponent)?
+            .finish()
+    }
+}
+
 impl<const SIZE: usize, EXP: PrimInt + Unsigned> Decimal<SIZE, EXP> {
     pub fn new(minus: bool, significant: [u8; SIZE], minus_exponent: bool, exponent: EXP) -> Self {
         for s in significant {