Move MathNumber into the library.

While this will be used for the OwnedLiterals since they must always exhibit the original DustJS behavior, I am going to keep exposing separate math functions for ContextElement instead of simply requiring them to implement Into<MathNumber> since people might want to implement math in unusual ways with unusual types.

src/bin.rs

@@ -5,13 +5,13 @@ use parser::Filter;
 use parser::OwnedLiteral;
 use parser::Template;
 use renderer::compile_template;
-use renderer::math_ints;
 use renderer::CompileError;
 use renderer::ContextElement;
 use renderer::DustRenderer;
 use renderer::IceResult;
 use renderer::IntoContextElement;
 use renderer::Loopable;
+use renderer::MathNumber;
 use renderer::RenderError;
 use renderer::Renderable;
 use renderer::Truthiness;
@@ -22,7 +22,6 @@ use std::convert::TryInto;
 use std::env;
 use std::fs;
 use std::io::{self, Read};
-use std::ops::Add;
 use std::path::Path;
 
 mod parser;
@@ -561,13 +560,6 @@ where
     }
 }
 
-#[derive(Debug)]
-enum MathNumber {
-    Integer(i128),
-    Decimal(f64),
-    Failure,
-}
-
 impl From<&serde_json::Value> for MathNumber {
     fn from(original: &serde_json::Value) -> Self {
         match original {
@@ -611,41 +603,6 @@ impl From<&serde_json::Number> for MathNumber {
     }
 }
 
-impl From<&OwnedLiteral> for MathNumber {
-    fn from(original: &OwnedLiteral) -> Self {
-        match original {
-            OwnedLiteral::LString(_) => panic!("Strings should not be cast to numbers for math"),
-            OwnedLiteral::LPositiveInteger(num) => {
-                return MathNumber::Integer((*num).try_into().unwrap())
-            }
-            OwnedLiteral::LNegativeInteger(num) => return MathNumber::Integer((*num).into()),
-            OwnedLiteral::LFloat(num) => return MathNumber::Decimal(*num),
-        }
-    }
-}
-
-impl Add<MathNumber> for MathNumber {
-    type Output = Option<OwnedLiteral>;
-
-    fn add(self, other: MathNumber) -> Self::Output {
-        match (self, other) {
-            (MathNumber::Failure, _) | (_, MathNumber::Failure) => None,
-            (MathNumber::Integer(self_num), MathNumber::Integer(other_num)) => {
-                math_ints(self_num, other_num, std::ops::Add::add)
-            }
-            (MathNumber::Decimal(self_num), MathNumber::Decimal(other_num)) => {
-                Some(OwnedLiteral::LFloat(self_num + other_num))
-            }
-            (MathNumber::Integer(self_num), MathNumber::Decimal(other_num)) => {
-                Some(OwnedLiteral::LFloat((self_num as f64) + other_num))
-            }
-            (MathNumber::Decimal(self_num), MathNumber::Integer(other_num)) => {
-                Some(OwnedLiteral::LFloat(self_num + (other_num as f64)))
-            }
-        }
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;