From ebe6ace9cee3acf9f482f5921f3e4538e80d0bae Mon Sep 17 00:00:00 2001
From: Steven Roose <steven@stevenroose.org>
Date: Wed, 29 May 2019 12:34:54 +0100
Subject: [PATCH] Add human-readable serde for OutPoint as `<txid>:<vout>`

---
 src/blockdata/transaction.rs |   2 +-
 src/internal_macros.rs       | 164 +++++++++++++++++++++++++++++++++++
 2 files changed, 165 insertions(+), 1 deletion(-)

diff --git a/src/blockdata/transaction.rs b/src/blockdata/transaction.rs
index dbe1b11173..4af85d7eda 100644
--- a/src/blockdata/transaction.rs
+++ b/src/blockdata/transaction.rs
@@ -45,7 +45,7 @@ pub struct OutPoint {
     /// The index of the referenced output in its transaction's vout
     pub vout: u32,
 }
-serde_struct_impl!(OutPoint, txid, vout);
+serde_struct_human_string_impl!(OutPoint, "an OutPoint", txid, vout);
 
 impl OutPoint {
     /// Creates a "null" `OutPoint`.
diff --git a/src/internal_macros.rs b/src/internal_macros.rs
index 056d905e77..648a134cad 100644
--- a/src/internal_macros.rs
+++ b/src/internal_macros.rs
@@ -459,6 +459,170 @@ macro_rules! serde_string_impl {
     };
 }
 
+/// A combination of serde_struct_impl and serde_string_impl where string is
+/// used for human-readable serialization and struct is used for
+/// non-human-readable serialization.
+macro_rules! serde_struct_human_string_impl {
+    ($name:ident, $expecting:expr, $($fe:ident),*) => (
+        #[cfg(feature = "serde")]
+        impl<'de> $crate::serde::Deserialize<'de> for $name {
+            fn deserialize<D>(deserializer: D) -> Result<$name, D::Error>
+            where
+                D: $crate::serde::de::Deserializer<'de>,
+            {
+                if deserializer.is_human_readable() {
+                    use std::fmt::{self, Formatter};
+                    use std::str::FromStr;
+
+                    struct Visitor;
+                    impl<'de> $crate::serde::de::Visitor<'de> for Visitor {
+                        type Value = $name;
+
+                        fn expecting(&self, formatter: &mut Formatter) -> fmt::Result {
+                            formatter.write_str($expecting)
+                        }
+
+                        fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+                        where
+                            E: $crate::serde::de::Error,
+                        {
+                            $name::from_str(v).map_err(E::custom)
+                        }
+
+                        fn visit_borrowed_str<E>(self, v: &'de str) -> Result<Self::Value, E>
+                        where
+                            E: $crate::serde::de::Error,
+                        {
+                            self.visit_str(v)
+                        }
+
+                        fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
+                        where
+                            E: $crate::serde::de::Error,
+                        {
+                            self.visit_str(&v)
+                        }
+                    }
+
+                    deserializer.deserialize_str(Visitor)
+                } else {
+                    use $crate::std::fmt::{self, Formatter};
+                    use $crate::serde::de::IgnoredAny;
+
+                    #[allow(non_camel_case_types)]
+                    enum Enum { Unknown__Field, $($fe),* }
+
+                    struct EnumVisitor;
+                    impl<'de> $crate::serde::de::Visitor<'de> for EnumVisitor {
+                        type Value = Enum;
+
+                        fn expecting(&self, formatter: &mut Formatter) -> fmt::Result {
+                            formatter.write_str("a field name")
+                        }
+
+                        fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+                        where
+                            E: $crate::serde::de::Error,
+                        {
+                            match v {
+                                $(
+                                stringify!($fe) => Ok(Enum::$fe)
+                                ),*,
+                                _ => Ok(Enum::Unknown__Field)
+                            }
+                        }
+                    }
+
+                    impl<'de> $crate::serde::Deserialize<'de> for Enum {
+                        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+                        where
+                            D: $crate::serde::de::Deserializer<'de>,
+                        {
+                            deserializer.deserialize_str(EnumVisitor)
+                        }
+                    }
+
+                    struct Visitor;
+
+                    impl<'de> $crate::serde::de::Visitor<'de> for Visitor {
+                        type Value = $name;
+
+                        fn expecting(&self, formatter: &mut Formatter) -> fmt::Result {
+                            formatter.write_str("a struct")
+                        }
+
+                        fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
+                        where
+                            A: $crate::serde::de::MapAccess<'de>,
+                        {
+                            use $crate::serde::de::Error;
+
+                            $(let mut $fe = None;)*
+
+                            loop {
+                                match map.next_key::<Enum>()? {
+                                    Some(Enum::Unknown__Field) => {
+                                        map.next_value::<IgnoredAny>()?;
+                                    }
+                                    $(
+                                        Some(Enum::$fe) => {
+                                            $fe = Some(map.next_value()?);
+                                        }
+                                    )*
+                                    None => { break; }
+                                }
+                            }
+
+                            $(
+                                let $fe = match $fe {
+                                    Some(x) => x,
+                                    None => return Err(A::Error::missing_field(stringify!($fe))),
+                                };
+                            )*
+
+                            let ret = $name {
+                                $($fe: $fe),*
+                            };
+
+                            Ok(ret)
+                        }
+                    }
+                    // end type defs
+
+                    static FIELDS: &'static [&'static str] = &[$(stringify!($fe)),*];
+
+                    deserializer.deserialize_struct(stringify!($name), FIELDS, Visitor)
+                }
+            }
+        }
+
+        #[cfg(feature = "serde")]
+        impl<'de> $crate::serde::Serialize for $name {
+            fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+            where
+                S: $crate::serde::Serializer,
+            {
+                if serializer.is_human_readable() {
+                    serializer.serialize_str(&self.to_string())
+                } else {
+                    use $crate::serde::ser::SerializeStruct;
+
+                    // Only used to get the struct length.
+                    static FIELDS: &'static [&'static str] = &[$(stringify!($fe)),*];
+
+                    let mut st = serializer.serialize_struct(stringify!($name), FIELDS.len())?;
+
+                    $(
+                        st.serialize_field(stringify!($fe), &self.$fe)?;
+                    )*
+
+                    st.end()
+                }
+            }
+        }
+    )
+}
+
 macro_rules! user_enum {
     (
         $(#[$attr:meta])*