Reintroduce public reexports as deprecated replacement modules & types.

Due to limitations described in
rust-lang/rust#30827, we can't just deprecate
the `pub use` stanzas; instead, we have to replace reexports with
new (deprecated) modules and public types which then internally reexport
the module internals or alias the reexported types, respectively.

components/zcash_address/CHANGELOG.md

@@ -7,6 +7,9 @@ and this library adheres to Rust's notion of
 
 ## [Unreleased]
 
+### Deprecated
+- `zcash_address::Network` (use `zcash_protocol::consensus::NetworkType` instead).
+
 ## [0.6.2] - 2024-12-13
 ### Fixed
 - Migrated to `f4jumble 0.1.1` to fix `no-std` support.

components/zcash_address/src/lib.rs

@@ -137,8 +137,6 @@ extern crate alloc;
 #[cfg(feature = "std")]
 extern crate std;
 
-use alloc::string::String;
-
 mod convert;
 mod encoding;
 mod kind;
@@ -151,8 +149,14 @@ pub use convert::{
 };
 pub use encoding::ParseError;
 pub use kind::unified;
+
+use alloc::string::String;
+
 use kind::unified::Receiver;
-//pub use zcash_protocol::consensus::NetworkType as Network;
+
+#[deprecated(note = "use ::zcash_protocol::consensus::NetworkType instead")]
+pub type Network = zcash_protocol::consensus::NetworkType;
+
 use zcash_protocol::{consensus::NetworkType, PoolType};
 
 /// A Zcash address.

zcash_client_backend/CHANGELOG.md

@@ -10,6 +10,14 @@ and this library adheres to Rust's notion of
 ### Changed
 - Migrated to `nonempty 0.11`
 
+### Deprecated
+- `zcash_client_backend::address` (use `zcash_keys::address` instead)
+- `zcash_client_backend::encoding` (use `zcash_keys::encoding` instead)
+- `zcash_client_backend::keys` (use `zcash_keys::keys` instead)
+- `zcash_client_backend::zip321` (use the `zip321` crate instead)
+- `zcash_client_backend::PoolType` (use `zcash_protocol::PoolType` instead)
+- `zcash_client_backend::ShieldedProtocol` (use `zcash_protocol::ShieldedProtocol` instead)
+
 ## [0.16.0] - 2024-12-16
 
 ### Added

zcash_client_backend/src/lib.rs

@@ -61,18 +61,14 @@
 // Temporary until we have addressed all Result<T, ()> cases.
 #![allow(clippy::result_unit_err)]
 
-//pub use zcash_keys::address;
 pub mod data_api;
 mod decrypt;
-//pub use zcash_keys::encoding;
 pub mod fees;
-//pub use zcash_keys::keys;
 pub mod proposal;
 pub mod proto;
 pub mod scan;
 pub mod scanning;
 pub mod wallet;
-//pub use zip321;
 
 #[cfg(feature = "sync")]
 pub mod sync;
@@ -84,7 +80,27 @@ pub mod serialization;
 pub mod tor;
 
 pub use decrypt::{decrypt_transaction, DecryptedOutput, TransferType};
-//pub use zcash_protocol::{PoolType, ShieldedProtocol};
+
+#[deprecated(note = "This module is deprecated; use `::zcash_keys::address` instead.")]
+pub mod address {
+    pub use zcash_keys::address::*;
+}
+#[deprecated(note = "This module is deprecated; use `::zcash_keys::encoding` instead.")]
+pub mod encoding {
+    pub use zcash_keys::encoding::*;
+}
+#[deprecated(note = "This module is deprecated; use `::zcash_keys::keys` instead.")]
+pub mod keys {
+    pub use zcash_keys::keys::*;
+}
+#[deprecated(note = "use ::zcash_protocol::PoolType instead")]
+pub type PoolType = zcash_protocol::PoolType;
+#[deprecated(note = "use ::zcash_protocol::ShieldedProtocol instead")]
+pub type ShieldedProtocol = zcash_protocol::ShieldedProtocol;
+#[deprecated(note = "This module is deprecated; use the `zip321` crate instead.")]
+pub mod zip321 {
+    pub use zip321::*;
+}
 
 #[cfg(test)]
 #[macro_use]