Parse decimals as BigDecimal (#2644)

Use implicit serde from BigDecimal crate

crates/nu-parser/src/parse.rs

@@ -15,6 +15,7 @@ use num_bigint::BigInt;
 use crate::lite_parse::{lite_parse, LiteBlock, LiteCommand, LitePipeline};
 use crate::path::expand_path;
 use crate::signature::SignatureRegistry;
+use bigdecimal::BigDecimal;
 
 /// Parses a simple column path, one without a variable (implied or explicit) at the head
 fn parse_simple_column_path(lite_arg: &Spanned<String>) -> (SpannedExpression, Option<ParseError>) {
@@ -740,15 +741,11 @@ fn parse_arg(
                     SpannedExpression::new(Expression::integer(x), lite_arg.span),
                     None,
                 )
-            } else if let Ok(x) = lite_arg.item.parse::<f64>() {
-                if let Ok(x) = Expression::decimal(x) {
-                    (SpannedExpression::new(x, lite_arg.span), None)
-                } else {
+            } else if let Ok(x) = lite_arg.item.parse::<BigDecimal>() {
                 (
-                        garbage(lite_arg.span),
-                        Some(ParseError::mismatch("number", lite_arg.clone())),
+                    SpannedExpression::new(Expression::decimal(x), lite_arg.span),
+                    None,
                 )
-                }
             } else {
                 (
                     garbage(lite_arg.span),
@@ -765,7 +762,7 @@ fn parse_arg(
             } else {
                 (
                     garbage(lite_arg.span),
-                    Some(ParseError::mismatch("number", lite_arg.clone())),
+                    Some(ParseError::mismatch("int", lite_arg.clone())),
                 )
             }
         }
@@ -951,43 +948,59 @@ mod test {
 
     #[test]
     fn parse_number() -> Result<(), ParseError> {
+        let registry = MockRegistry::new();
+
         let raw = "-32.2".to_string();
         let input = raw.clone().spanned(Span::new(0, raw.len()));
-        let registry = MockRegistry::new();
         let result = parse_arg(SyntaxShape::Number, &registry, &input);
         assert_eq!(result.1, None);
-        assert_eq!(result.0.expr, Expression::decimal(-32.2)?);
+        assert_eq!(
+            result.0.expr,
+            Expression::decimal(BigDecimal::new(BigInt::from(-322), 1))
+        );
 
         let raw = "32.2".to_string();
         let input = raw.clone().spanned(Span::new(0, raw.len()));
-        let registry = MockRegistry::new();
         let result = parse_arg(SyntaxShape::Number, &registry, &input);
         assert_eq!(result.1, None);
-        assert_eq!(result.0.expr, Expression::decimal(32.2)?);
+        assert_eq!(
+            result.0.expr,
+            Expression::decimal(BigDecimal::new(BigInt::from(322), 1))
+        );
+
+        let raw = "36893488147419103232.54".to_string();
+        let input = raw.clone().spanned(Span::new(0, raw.len()));
+        let result = parse_arg(SyntaxShape::Number, &registry, &input);
+        assert_eq!(result.1, None);
+        assert_eq!(
+            result.0.expr,
+            Expression::decimal(BigDecimal::new(
+                BigInt::from(3689348814741910323254 as i128),
+                2
+            ))
+        );
 
         let raw = "-34".to_string();
         let input = raw.clone().spanned(Span::new(0, raw.len()));
-        let registry = MockRegistry::new();
         let result = parse_arg(SyntaxShape::Number, &registry, &input);
         assert_eq!(result.1, None);
         assert_eq!(result.0.expr, Expression::integer(BigInt::from(-34)));
 
         let raw = "34".to_string();
         let input = raw.clone().spanned(Span::new(0, raw.len()));
-        let registry = MockRegistry::new();
         let result = parse_arg(SyntaxShape::Number, &registry, &input);
         assert_eq!(result.1, None);
         assert_eq!(result.0.expr, Expression::integer(BigInt::from(34)));
 
         let raw = "36893488147419103232".to_string();
         let input = raw.clone().spanned(Span::new(0, raw.len()));
-        let registry = MockRegistry::new();
         let result = parse_arg(SyntaxShape::Number, &registry, &input);
         assert_eq!(result.1, None);
         assert_eq!(
             result.0.expr,
             Expression::integer(BigInt::from(36893488147419103232 as u128))
         );
+
         Ok(())
     }
 }

crates/nu-protocol/src/hir.rs

@@ -1099,18 +1099,8 @@ impl Expression {
         Expression::Literal(Literal::Number(Number::Int(i)))
     }
 
-    pub fn decimal(f: f64) -> Result<Expression, ParseError> {
-        let dec = BigDecimal::from_f64(f);
-
-        let dec = match dec {
-            Some(x) => Ok(x),
-            None => Err(ParseError::internal_error(
-                "Can not convert f64 to big decimal"
-                    .to_string()
-                    .spanned_unknown(),
-            )),
-        }?;
-        Ok(Expression::Literal(Literal::Number(Number::Decimal(dec))))
+    pub fn decimal(dec: BigDecimal) -> Expression {
+        Expression::Literal(Literal::Number(Number::Decimal(dec)))
     }
 
     pub fn string(s: String) -> Expression {

crates/nu-protocol/src/value.rs

@@ -7,7 +7,6 @@ pub mod evaluate;
 pub mod iter;
 pub mod primitive;
 pub mod range;
-mod serde_bigdecimal;
 
 use crate::hir;
 use crate::type_name::{ShellTypeName, SpannedTypeName};

crates/nu-protocol/src/value/primitive.rs

@@ -1,7 +1,6 @@
 use crate::type_name::ShellTypeName;
 use crate::value::column_path::ColumnPath;
 use crate::value::range::{Range, RangeInclusion};
-use crate::value::serde_bigdecimal;
 use bigdecimal::BigDecimal;
 use chrono::{DateTime, Utc};
 use nu_errors::{ExpectedRange, ShellError};
@@ -27,7 +26,6 @@ pub enum Primitive {
     /// A "big int", an integer with arbitrarily large size (aka not limited to 64-bit)
     Int(BigInt),
     /// A "big decimal", an decimal number with arbitrarily large size (aka not limited to 64-bit)
-    #[serde(with = "serde_bigdecimal")]
     Decimal(BigDecimal),
     /// A count in the number of bytes, used as a filesize
     Filesize(u64),

crates/nu-protocol/src/value/serde_bigdecimal.rs

@@ -1,26 +0,0 @@
-use bigdecimal::BigDecimal;
-use num_traits::cast::FromPrimitive;
-use num_traits::cast::ToPrimitive;
-
-/// Enable big decimal serialization by providing a `serialize` function
-pub fn serialize<S>(big_decimal: &BigDecimal, serializer: S) -> Result<S::Ok, S::Error>
-where
-    S: serde::Serializer,
-{
-    serde::Serialize::serialize(
-        &big_decimal
-            .to_f64()
-            .ok_or_else(|| serde::ser::Error::custom("expected a f64-sized bignum"))?,
-        serializer,
-    )
-}
-
-/// Enable big decimal deserialization by providing a `deserialize` function
-pub fn deserialize<'de, D>(deserializer: D) -> Result<BigDecimal, D::Error>
-where
-    D: serde::Deserializer<'de>,
-{
-    let x: f64 = serde::Deserialize::deserialize(deserializer)?;
-    Ok(BigDecimal::from_f64(x)
-        .ok_or_else(|| serde::de::Error::custom("expected a f64-sized bigdecimal"))?)
-}