Introduced from float API for Monero quantities

Cargo.lock

@@ -2885,10 +2885,11 @@ dependencies = [
 
 [[package]]
 name = "rust_decimal"
-version = "1.9.0"
+version = "1.10.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a5c739ba050709eae138f053356d27ff818d71fe54ce5a8d9f4c7a660bfb6684"
+checksum = "e3e5a94e2006dd60c603d8481c65b665b4b6694f78d23e15869ad10eb883e36e"
 dependencies = [
+ "arrayvec",
  "num-traits",
  "serde",
 ]

swap/Cargo.toml

@@ -40,7 +40,7 @@ pem = "0.8"
 prettytable-rs = "0.8"
 rand = "0.7"
 reqwest = { version = "0.11", default-features = false }
-rust_decimal = "1.8"
+rust_decimal = "1.10"
 serde = { version = "1", features = ["derive"] }
 serde_cbor = "0.11"
 serde_derive = "1.0"

swap/src/monero.rs

@@ -15,6 +15,7 @@ use rust_decimal::{
 };
 use serde::{Deserialize, Serialize};
 use std::{
+    convert::TryFrom,
     fmt::Display,
     ops::{Add, Mul, Sub},
     str::FromStr,
@@ -88,13 +89,22 @@ impl Amount {
         self.0
     }
 
+    pub fn from_monero(amount: f64) -> Result<Self> {
+        let decimal = Decimal::try_from(amount)?;
+        Self::from_decimal(decimal)
+    }
+
     pub fn parse_monero(amount: &str) -> Result<Self> {
         let decimal = Decimal::from_str(amount)?;
+        Self::from_decimal(decimal)
+    }
+
+    fn from_decimal(amount: Decimal) -> Result<Self> {
         let piconeros_dec =
-            decimal.mul(Decimal::from_u64(PICONERO_OFFSET).expect("constant to fit into u64"));
+            amount.mul(Decimal::from_u64(PICONERO_OFFSET).expect("constant to fit into u64"));
         let piconeros = piconeros_dec
             .to_u64()
-            .ok_or_else(|| OverflowError(amount.to_owned()))?;
+            .ok_or_else(|| OverflowError(amount.to_string()))?;
         Ok(Amount(piconeros))
     }
 }