Define custom String type with complete macro

Separate `uniffi::custom_type` and `impl_string_custom_typedef`
calls were made to define uniffi String types. This combines them
into one macro.

Author: DanGould

src/lib.rs

@@ -330,9 +330,7 @@ impl From<bitcoin::Network> for Network {
     }
 }
 
-uniffi::custom_type!(Txid, String);
-impl_string_custom_typedef!(Txid);
-uniffi::custom_type!(BlockHash, String);
-impl_string_custom_typedef!(BlockHash);
+define_custom_string_type!(Txid);
+define_custom_string_type!(BlockHash);
 
 uniffi::setup_scaffolding!("bitcoin");

src/macros.rs

@@ -18,8 +18,10 @@ macro_rules! impl_from_ffi_type {
     };
 }
 
-macro_rules! impl_string_custom_typedef {
+macro_rules! define_custom_string_type {
     ($ffi_type:ident) => {
+        uniffi::custom_type!($ffi_type, String);
+
         impl UniffiCustomTypeConverter for $ffi_type {
             type Builtin = String;
             fn into_custom(val: Self::Builtin) -> uniffi::Result<Self> {