Merge rust-bitcoin/rust-miniscript#325: Constructing descriptors from inner types

5dad2d8db1c55c8c2c08d4f81fbf466ea332b8d4 Constructing descriptors from inner types (Dr Maxim Orlovsky)

Pull request description:

ACKs for top commit:
  sanket1729:
    utACK 5dad2d8db1c55c8c2c08d4f81fbf466ea332b8d4. Would it make sense to add utility methods rust-bitcoin/rust-secp256k1#428 ? I always find the `From` annoying to use.
  apoelstra:
    ACK 5dad2d8db1c55c8c2c08d4f81fbf466ea332b8d4

Tree-SHA512: 4487395342a5fedd1918380d69e1eb8b868931a1e0c3dd95e23ce351b79b4ff21fa80bab52482058a06c38750eba95460328c649605a58bfaca4330d39a33171

Author: heap-coder

src/descriptor/mod.rs

@@ -190,6 +190,48 @@ pub enum Descriptor<Pk: MiniscriptKey> {
     Tr(Tr<Pk>),
 }
 
+impl<Pk: MiniscriptKey> From<Bare<Pk>> for Descriptor<Pk> {
+    #[inline]
+    fn from(inner: Bare<Pk>) -> Self {
+        Descriptor::Bare(inner)
+    }
+}
+
+impl<Pk: MiniscriptKey> From<Pkh<Pk>> for Descriptor<Pk> {
+    #[inline]
+    fn from(inner: Pkh<Pk>) -> Self {
+        Descriptor::Pkh(inner)
+    }
+}
+
+impl<Pk: MiniscriptKey> From<Wpkh<Pk>> for Descriptor<Pk> {
+    #[inline]
+    fn from(inner: Wpkh<Pk>) -> Self {
+        Descriptor::Wpkh(inner)
+    }
+}
+
+impl<Pk: MiniscriptKey> From<Sh<Pk>> for Descriptor<Pk> {
+    #[inline]
+    fn from(inner: Sh<Pk>) -> Self {
+        Descriptor::Sh(inner)
+    }
+}
+
+impl<Pk: MiniscriptKey> From<Wsh<Pk>> for Descriptor<Pk> {
+    #[inline]
+    fn from(inner: Wsh<Pk>) -> Self {
+        Descriptor::Wsh(inner)
+    }
+}
+
+impl<Pk: MiniscriptKey> From<Tr<Pk>> for Descriptor<Pk> {
+    #[inline]
+    fn from(inner: Tr<Pk>) -> Self {
+        Descriptor::Tr(inner)
+    }
+}
+
 /// Descriptor Type of the descriptor
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
 pub enum DescriptorType {