chore: add example script to generate a verifier contract

noir/Earthfile

@@ -44,6 +44,18 @@ test:
   COPY noir-repo/.rustfmt.toml noir-repo/.rustfmt.toml
   RUN ./scripts/test_native.sh
 
+examples:
+  FROM +nargo
+  ENV PATH="/usr/src/noir-repo/target/release:${PATH}"
+
+  COPY --dir noir-repo/examples noir-repo
+  COPY ../barretenberg/cpp/+preset-clang-assert/bin/bb /usr/src/barretenberg/cpp/build/bin/bb
+
+  ENV BACKEND=/usr/src/barretenberg/cpp/build/bin/bb
+
+  WORKDIR noir-repo/examples/codegen-verifier
+  RUN ./test.sh
+
 format:
   FROM +nargo
   ENV PATH=$PATH:/usr/src/noir-repo/target/release

noir/noir-repo/examples/codegen-verifier/Nargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "hello_world"
+type = "bin"
+authors = [""]
+compiler_version = ">=0.29.0"
+
+[dependencies]

noir/noir-repo/examples/codegen-verifier/codegen_verifier.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+set -eu
+
+BACKEND=${BACKEND:-bb}
+
+nargo compile
+
+# TODO: backend should automatically generate vk if necessary.
+$BACKEND write_vk -b ./target/hello_world.json
+$BACKEND contract -v ./target/vk

noir/noir-repo/examples/codegen-verifier/src/main.nr

@@ -0,0 +1,3 @@
+fn main(x: Field, y: pub Field) {
+    assert(x != y);
+}

noir/noir-repo/examples/codegen-verifier/test.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+set -eu
+
+# This file is used for Noir CI and is not required.
+
+BACKEND=${BACKEND:-bb}
+
+./codegen_verifier.sh
+
+if ! [ -f ./target/contract.sol ]; then 
+    printf '%s\n' "Contract not written to file" >&2
+    exit 1
+fi