Merge #643: call reduce0 from reduce1 and 2

5c48516 call reduce0 from reduce1 and 2 (Riccardo Casatta)

Pull request description:

  reduce code duplication by calling the function that provide the same check and side effects

ACKs for top commit:
  apoelstra:
    ACK 5c48516 neat!

Tree-SHA512: 7e37af561737e48dbe0d86d3bb86adc28d3a098155d6eb35f7686f7ff97597449de0b6356a9bae4dda943fb19f3cd9ff4f1b1bbca25cafc15f2b0eecb4dd27b3

src/miniscript/decode.rs

@@ -228,12 +228,7 @@ impl<Pk: MiniscriptKey, Ctx: ScriptContext> TerminalStack<Pk, Ctx> {
         let top = self.pop().unwrap();
         let wrapped_ms = wrap(Arc::new(top));
 
-        let ty = Type::type_check(&wrapped_ms)?;
-        let ext = ExtData::type_check(&wrapped_ms)?;
-        let ms = Miniscript { node: wrapped_ms, ty, ext, phantom: PhantomData };
-        Ctx::check_global_validity(&ms)?;
-        self.0.push(ms);
-        Ok(())
+        self.reduce0(wrapped_ms)
     }
 
     ///reduce, type check and push a 2-arg node
@@ -246,12 +241,7 @@ impl<Pk: MiniscriptKey, Ctx: ScriptContext> TerminalStack<Pk, Ctx> {
 
         let wrapped_ms = wrap(Arc::new(left), Arc::new(right));
 
-        let ty = Type::type_check(&wrapped_ms)?;
-        let ext = ExtData::type_check(&wrapped_ms)?;
-        let ms = Miniscript { node: wrapped_ms, ty, ext, phantom: PhantomData };
-        Ctx::check_global_validity(&ms)?;
-        self.0.push(ms);
-        Ok(())
+        self.reduce0(wrapped_ms)
     }
 }