From 288d5750468064e0f998b30c27e266f3cc97a417 Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Wed, 11 Aug 2021 18:15:17 +0800
Subject: [PATCH] Add log10 for Decimal.

---
 CHANGELOG.md               |  2 ++
 Cargo.toml                 |  2 +-
 src/packages/math_basic.rs | 19 +++++++++++++++++--
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 013025aa..8b8e8aac 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,8 @@ Enhancements
 * Added a number of constants to `Dynamic`.
 * Added a number of constants and `fromXXX` constant methods to `Dynamic`.
 * `parse_float()`, `PI()` and `E()` now defer to `Decimal` under `no_float` if `decimal` is turned on.
+* Added `log10()` for `Decimal`.
+* `ln` for `Decimal` is now checked and won't panic.
 
 
 Version 1.0.2
diff --git a/Cargo.toml b/Cargo.toml
index 701fdd60..cd52b2c9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -92,7 +92,7 @@ default-features = false
 optional = true
 
 [dependencies.rust_decimal]
-version = "1.14.2"
+version = "1.15"
 default-features = false
 features = ["maths"]
 optional = true
diff --git a/src/packages/math_basic.rs b/src/packages/math_basic.rs
index 53c0431b..f3c9c5ea 100644
--- a/src/packages/math_basic.rs
+++ b/src/packages/math_basic.rs
@@ -339,8 +339,23 @@ mod decimal_functions {
             Ok(x.exp())
         }
     }
-    pub fn ln(x: Decimal) -> Decimal {
-        x.ln()
+    #[rhai_fn(return_raw)]
+    pub fn ln(x: Decimal) -> Result<Decimal, Box<EvalAltResult>> {
+        if cfg!(not(feature = "unchecked")) {
+            x.checked_ln()
+                .ok_or_else(|| make_err(format!("Error taking the natural log of {}", x)))
+        } else {
+            Ok(x.ln())
+        }
+    }
+    #[rhai_fn(name = "log", return_raw)]
+    pub fn log10(x: Decimal) -> Result<Decimal, Box<EvalAltResult>> {
+        if cfg!(not(feature = "unchecked")) {
+            x.checked_log10()
+                .ok_or_else(|| make_err(format!("Error taking the log of {}", x)))
+        } else {
+            Ok(x.log10())
+        }
     }
     #[rhai_fn(name = "floor", get = "floor")]
     pub fn floor(x: Decimal) -> Decimal {