Improve BigDecimal parsing from Float with ryu crate (#1176)

Author: tyranron

juniper/Cargo.toml

@@ -31,7 +31,7 @@ default = [
     "url",
     "uuid",
 ]
-bigdecimal = ["dep:bigdecimal"]
+bigdecimal = ["dep:bigdecimal", "dep:ryu"]
 bson = ["dep:bson"]
 chrono = ["dep:chrono"]
 chrono-clock = ["chrono", "chrono/clock"]
@@ -59,6 +59,7 @@ graphql-parser = { version = "0.4", optional = true }
 indexmap = { version = "2.0", features = ["serde"] }
 juniper_codegen = { version = "0.16.0-dev", path = "../juniper_codegen" }
 rust_decimal = { version = "1.20", default-features = false, optional = true }
+ryu = { version = "1.0", optional = true }
 serde = { version = "1.0.122", features = ["derive"] }
 serde_json = { version = "1.0.18", default-features = false, optional = true }
 smartstring = "1.0"

juniper/src/integrations/bigdecimal.rs

@@ -44,7 +44,8 @@ mod bigdecimal_scalar {
         } else if let Some(f) = v.as_float_value() {
             // See akubera/bigdecimal-rs#103 for details:
             // https://github.com/akubera/bigdecimal-rs/issues/103
-            BigDecimal::from_str(&f.to_string())
+            let mut buf = ryu::Buffer::new();
+            BigDecimal::from_str(buf.format(f))
                 .map_err(|e| format!("Failed to parse `BigDecimal` from `Float`: {e}"))
         } else {
             v.as_string_value()