cxx experiment

Cargo.toml

@@ -3,9 +3,9 @@
 members = [
     "taskchampion/taskchampion",
     "taskchampion/sync-server",
-    "taskchampion/lib",
-    "taskchampion/integration-tests",
-    "taskchampion/xtask",
+    "src/tc",
+    #"taskchampion/integration-tests",
+    #"taskchampion/xtask",
 ]
 
 resolver = "2"

src/tc/CMakeLists.txt

@@ -13,6 +13,11 @@ corrosion_import_crate(
   LOCKED
   CRATES "taskchampion-lib")
 
+corrosion_add_cxxbridge(taskchampion-cpp
+        CRATE taskchampion-lib
+        FILES src/lib.rs
+)
+
 include_directories (${CMAKE_SOURCE_DIR}
                      ${CMAKE_SOURCE_DIR}/src
                      ${CMAKE_SOURCE_DIR}/src/tc
@@ -29,4 +34,4 @@ set (tc_SRCS
   Task.cpp Task.h)
 
 add_library (tc STATIC ${tc_SRCS})
-target_link_libraries(tc taskchampion-lib)
+target_link_libraries(tc taskchampion-lib taskchampion-cpp)

src/tc/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "taskchampion-lib"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[lib]
+crate-type = ["staticlib"]
+
+[dependencies]
+taskchampion = { path = "../../taskchampion/taskchampion", features = ["server-sync"] }
+cxx = "1.0"
+
+[build-dependencies]
+cxx-build = "1.0"

src/tc/build.rs

@@ -0,0 +1,6 @@
+#[allow(unused_must_use)]
+fn main() {
+    cxx_build::bridge("src/lib.rs");
+    println!("cargo:rerun-if-changed=build.rs");
+    println!("cargo:rerun-if-changed=src/lib.rs");
+}

src/tc/src/lib.rs

@@ -0,0 +1,17 @@
+use taskchampion::{Replica as RealReplica, StorageConfig};
+
+#[cxx::bridge(namespace = "tc")]
+mod ffi {
+    // Rust types and signatures exposed to C++.
+    extern "Rust" {
+        type Replica;
+        fn new_replica() -> Box<Replica>;
+    }
+}
+
+struct Replica(RealReplica);
+
+fn new_replica() -> Box<Replica> {
+    let storage = StorageConfig::InMemory.into_storage().unwrap();
+    Box::new(Replica(RealReplica::new(storage)))
+}

src/tc/src/main.cpp

@@ -0,0 +1,5 @@
+#include "lib.rs.h"
+
+int main() {
+    auto replica = tc::new_replica();
+}