feat(bb): add bb --version command (#2482)

This PR allows us to query the version of `bb` by calling `bb
--version`. This is needed by Nargo so that we can enforce that the user
is always speaking to the correct version of `bb`.

barretenberg/cpp/CMakeLists.txt

@@ -9,6 +9,13 @@ project(
     VERSION 0.7.10 # x-release-please-version
     LANGUAGES CXX C
 )
+# Insert version into `bb` config file
+configure_file(
+    ${CMAKE_CURRENT_SOURCE_DIR}/src/barretenberg/bb/config.hpp.in
+    ${CMAKE_CURRENT_SOURCE_DIR}/src/barretenberg/bb/config.hpp
+    @ONLY
+)
+
 
 option(DISABLE_ASM "Disable custom assembly" OFF)
 option(DISABLE_ADX "Disable ADX assembly variant" OFF)

barretenberg/cpp/src/barretenberg/bb/.gitignore

@@ -0,0 +1 @@
+config.hpp

barretenberg/cpp/src/barretenberg/bb/config.hpp.in

@@ -0,0 +1,6 @@
+#ifndef INCLUDE_GUARD
+#define INCLUDE_GUARD
+
+#define BB_VERSION "@CMAKE_PROJECT_VERSION@"
+
+#endif // INCLUDE_GUARD

barretenberg/cpp/src/barretenberg/bb/main.cpp

@@ -1,3 +1,4 @@
+#include "config.hpp"
 #include "get_bytecode.hpp"
 #include "get_crs.hpp"
 #include "get_witness.hpp"
@@ -334,7 +335,10 @@ int main(int argc, char* argv[])
         bool recursive = flagPresent(args, "-r") || flagPresent(args, "--recursive");
 
         // Skip CRS initialization for any command which doesn't require the CRS.
-        if (command == "info") {
+        if (command == "--version") {
+            writeStringToStdout(BB_VERSION);
+            return 0;
+        } else if (command == "info") {
             std::string output_path = getOption(args, "-o", "info.json");
             acvmInfo(output_path);
             return 0;