From b74b4eaf7acf6becd0f98ab25d0d5ccde3affebe Mon Sep 17 00:00:00 2001
From: Tom French <15848336+TomAFrench@users.noreply.github.com>
Date: Thu, 7 Nov 2024 14:09:13 +0000
Subject: [PATCH] chore: update example to show how to split public inputs in
 bash (#6472)

---
 examples/codegen_verifier/codegen_verifier.sh | 13 +++++++++----
 examples/codegen_verifier/src/main.nr         |  4 ++--
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/examples/codegen_verifier/codegen_verifier.sh b/examples/codegen_verifier/codegen_verifier.sh
index fabd6235a67..f224f74168f 100755
--- a/examples/codegen_verifier/codegen_verifier.sh
+++ b/examples/codegen_verifier/codegen_verifier.sh
@@ -16,11 +16,17 @@ nargo execute witness
 PROOF_PATH=./target/proof
 $BACKEND prove -b ./target/hello_world.json -w ./target/witness.gz -o $PROOF_PATH
 
-NUM_PUBLIC_INPUTS=1
+# Sanity check that proof is valid.
+$BACKEND verify -k ./target/vk -p ./target/proof
+
+NUM_PUBLIC_INPUTS=2
 PUBLIC_INPUT_BYTES=$((32 * $NUM_PUBLIC_INPUTS))
 HEX_PUBLIC_INPUTS=$(head -c $PUBLIC_INPUT_BYTES $PROOF_PATH | od -An -v -t x1 | tr -d $' \n')
 HEX_PROOF=$(tail -c +$(($PUBLIC_INPUT_BYTES + 1)) $PROOF_PATH | od -An -v -t x1 | tr -d $' \n')
 
+# Split public inputs into strings where each string represents a `bytes32`.
+SPLIT_HEX_PUBLIC_INPUTS=$(sed -e 's/.\{64\}/0x&,/g' <<< $HEX_PUBLIC_INPUTS)
+
 # Spin up an anvil node to deploy the contract to
 anvil &
 
@@ -31,8 +37,7 @@ DEPLOY_INFO=$(forge create UltraVerifier \
 VERIFIER_ADDRESS=$(echo $DEPLOY_INFO | jq -r '.deployedTo')
 
 # Call the verifier contract with our proof.
-# Note that we haven't needed to split up `HEX_PUBLIC_INPUTS` as there's only a single public input
-cast call $VERIFIER_ADDRESS "verify(bytes, bytes32[])(bool)" "0x$HEX_PROOF" "[0x$HEX_PUBLIC_INPUTS]"
+cast call $VERIFIER_ADDRESS "verify(bytes, bytes32[])(bool)" "0x$HEX_PROOF" "[$SPLIT_HEX_PUBLIC_INPUTS]"
 
 # Stop anvil node again
-kill %-
\ No newline at end of file
+kill %-
diff --git a/examples/codegen_verifier/src/main.nr b/examples/codegen_verifier/src/main.nr
index baef0c3786a..93531797744 100644
--- a/examples/codegen_verifier/src/main.nr
+++ b/examples/codegen_verifier/src/main.nr
@@ -1,3 +1,3 @@
-fn main(x: Field, y: pub Field) {
+fn main(x: pub Field, y: pub Field) {
     assert(x != y);
-}
\ No newline at end of file
+}