From 54ef63baced8160ac3396966b60941ceab1dbb3f Mon Sep 17 00:00:00 2001
From: Jack Grigg <jack@z.cash>
Date: Wed, 12 Jun 2019 17:36:09 +0100
Subject: [PATCH] Place zcash_proofs::prover::LocalTxProver behind a feature
 flag

This enables zcash_proofs to be compiled to WASM, which the directories
crate doesn't support.
---
 zcash_proofs/Cargo.toml | 6 +++++-
 zcash_proofs/src/lib.rs | 8 ++++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/zcash_proofs/Cargo.toml b/zcash_proofs/Cargo.toml
index 9e989fa..598e013 100644
--- a/zcash_proofs/Cargo.toml
+++ b/zcash_proofs/Cargo.toml
@@ -9,9 +9,13 @@ authors = [
 bellman = { path = "../bellman" }
 blake2b_simd = "0.5"
 byteorder = "1"
-directories = "1"
+directories = { version = "1", optional = true }
 ff = { path = "../ff" }
 pairing = { path = "../pairing" }
 rand_os = "0.2"
 sapling-crypto = { path = "../sapling-crypto" }
 zcash_primitives = { path = "../zcash_primitives" }
+
+[features]
+default = ["local-prover"]
+local-prover = ["directories"]
diff --git a/zcash_proofs/src/lib.rs b/zcash_proofs/src/lib.rs
index 26aa2f1..d2dc877 100644
--- a/zcash_proofs/src/lib.rs
+++ b/zcash_proofs/src/lib.rs
@@ -1,13 +1,15 @@
 extern crate bellman;
 extern crate blake2b_simd;
 extern crate byteorder;
-extern crate directories;
 extern crate ff;
 extern crate pairing;
 extern crate rand_os;
 extern crate sapling_crypto;
 extern crate zcash_primitives;
 
+#[cfg(feature = "local-prover")]
+extern crate directories;
+
 use bellman::groth16::{prepare_verifying_key, Parameters, PreparedVerifyingKey, VerifyingKey};
 use pairing::bls12_381::Bls12;
 use std::fs::File;
@@ -15,9 +17,11 @@ use std::io::{self, BufReader};
 use std::path::Path;
 
 mod hashreader;
-pub mod prover;
 pub mod sapling;
 
+#[cfg(feature = "local-prover")]
+pub mod prover;
+
 pub fn load_parameters(
     spend_path: &Path,
     spend_hash: &str,