From 5f2a0d2714c200f1bd7ad7d19c5848822153022e Mon Sep 17 00:00:00 2001
From: maciektr <maciej.tratnowiecki@swmansion.com>
Date: Mon, 29 Jan 2024 11:21:12 +0100
Subject: [PATCH] Create shared proc-macro primitives lib

commit-id:4d5003fc
---
 Cargo.lock                                    | 11 +++++
 Cargo.toml                                    |  1 +
 scarb/Cargo.toml                              |  1 +
 utils/scarb-proc-macro-interface/Cargo.toml   | 19 ++++++++
 utils/scarb-proc-macro-interface/README.md    |  1 +
 utils/scarb-proc-macro-interface/src/lib.rs   |  2 +
 .../scarb-proc-macro-interface/src/plugin.rs  | 46 +++++++++++++++++++
 .../scarb-proc-macro-interface/src/shared.rs  | 17 +++++++
 8 files changed, 98 insertions(+)
 create mode 100644 utils/scarb-proc-macro-interface/Cargo.toml
 create mode 100644 utils/scarb-proc-macro-interface/README.md
 create mode 100644 utils/scarb-proc-macro-interface/src/lib.rs
 create mode 100644 utils/scarb-proc-macro-interface/src/plugin.rs
 create mode 100644 utils/scarb-proc-macro-interface/src/shared.rs

diff --git a/Cargo.lock b/Cargo.lock
index b57eb001f..9256f9b38 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4487,6 +4487,7 @@ dependencies = [
  "reqwest",
  "scarb-build-metadata",
  "scarb-metadata 1.11.0",
+ "scarb-proc-macro-interface",
  "scarb-test-support",
  "scarb-ui",
  "semver",
@@ -4607,6 +4608,16 @@ dependencies = [
  "thiserror",
 ]
 
+[[package]]
+name = "scarb-proc-macro-interface"
+version = "0.0.1"
+dependencies = [
+ "anyhow",
+ "libc",
+ "serde",
+ "serde_json",
+]
+
 [[package]]
 name = "scarb-snforge-test-collector"
 version = "2.5.3"
diff --git a/Cargo.toml b/Cargo.toml
index c33aea1e1..f4f11c292 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,6 +8,7 @@ members = [
     "extensions/scarb-snforge-test-collector",
     "utils/create-output-dir",
     "utils/scarb-build-metadata",
+    "utils/scarb-proc-macro-interface",
     "utils/scarb-test-support",
     "utils/scarb-ui",
     "utils/test-for-each-example",
diff --git a/scarb/Cargo.toml b/scarb/Cargo.toml
index b120ab443..f1d0fb029 100644
--- a/scarb/Cargo.toml
+++ b/scarb/Cargo.toml
@@ -78,6 +78,7 @@ windows-sys.workspace = true
 xxhash-rust.workspace = true
 zip.workspace = true
 zstd.workspace = true
+scarb-proc-macro-interface = { path = "../utils/scarb-proc-macro-interface" }
 
 [target.'cfg(not(target_os = "linux"))'.dependencies]
 reqwest = { workspace = true, default-features = true}
diff --git a/utils/scarb-proc-macro-interface/Cargo.toml b/utils/scarb-proc-macro-interface/Cargo.toml
new file mode 100644
index 000000000..aab014566
--- /dev/null
+++ b/utils/scarb-proc-macro-interface/Cargo.toml
@@ -0,0 +1,19 @@
+[package]
+name = "scarb-proc-macro-interface"
+version = "0.0.1"
+edition.workspace = true
+
+authors.workspace = true
+categories = ["development-tools"]
+description = "Cariro procedural macro interface primitives."
+homepage.workspace = true
+keywords = ["scarb"]
+license.workspace = true
+readme = "README.md"
+repository.workspace = true
+
+[dependencies]
+anyhow.workspace = true
+serde.workspace = true
+serde_json.workspace = true
+libc.workspace = true
diff --git a/utils/scarb-proc-macro-interface/README.md b/utils/scarb-proc-macro-interface/README.md
new file mode 100644
index 000000000..406164e33
--- /dev/null
+++ b/utils/scarb-proc-macro-interface/README.md
@@ -0,0 +1 @@
+# scarb-proc-macro-interface
diff --git a/utils/scarb-proc-macro-interface/src/lib.rs b/utils/scarb-proc-macro-interface/src/lib.rs
new file mode 100644
index 000000000..14f5e881e
--- /dev/null
+++ b/utils/scarb-proc-macro-interface/src/lib.rs
@@ -0,0 +1,2 @@
+pub mod plugin;
+pub mod shared;
diff --git a/utils/scarb-proc-macro-interface/src/plugin.rs b/utils/scarb-proc-macro-interface/src/plugin.rs
new file mode 100644
index 000000000..58c78b546
--- /dev/null
+++ b/utils/scarb-proc-macro-interface/src/plugin.rs
@@ -0,0 +1,46 @@
+use crate::shared::{FfiProcMacroResult, FfiTokenStream};
+use std::ffi::CString;
+
+#[derive(Debug)]
+#[allow(dead_code)]
+pub enum ProcMacroResult {
+    /// Plugin has not taken any action.
+    Leave,
+    /// Plugin generated TokenStream replacement.
+    Replace(TokenStream),
+    /// Plugin ordered item removal.
+    Remove,
+}
+
+#[derive(Debug, Default, Clone)]
+pub struct TokenStream(String);
+
+impl FfiTokenStream {
+    /// # Safety
+    pub unsafe fn to_string(&self) -> String {
+        if self.0.is_null() {
+            String::default()
+        } else {
+            let cstr = CString::from_raw(self.0);
+            cstr.to_string_lossy().to_string()
+        }
+    }
+}
+
+impl TokenStream {
+    /// # Safety
+    pub unsafe fn to_ffi(&self) -> FfiTokenStream {
+        FfiTokenStream(CString::new(self.0.clone()).unwrap().into_raw())
+    }
+}
+
+impl ProcMacroResult {
+    /// # Safety
+    pub unsafe fn to_ffi(&self) -> FfiProcMacroResult {
+        match self {
+            Self::Leave => FfiProcMacroResult::Leave,
+            Self::Remove => FfiProcMacroResult::Remove,
+            Self::Replace(token_stream) => FfiProcMacroResult::Replace(token_stream.to_ffi()),
+        }
+    }
+}
diff --git a/utils/scarb-proc-macro-interface/src/shared.rs b/utils/scarb-proc-macro-interface/src/shared.rs
new file mode 100644
index 000000000..c78625296
--- /dev/null
+++ b/utils/scarb-proc-macro-interface/src/shared.rs
@@ -0,0 +1,17 @@
+use std::os::raw::c_char;
+
+#[repr(C)]
+#[derive(Debug)]
+#[allow(dead_code)]
+pub enum FfiProcMacroResult {
+    /// Plugin has not taken any action.
+    Leave,
+    /// Plugin generated TokenStream replacement.
+    Replace(FfiTokenStream),
+    /// Plugin ordered item removal.
+    Remove,
+}
+
+#[repr(C)]
+#[derive(Debug)]
+pub struct FfiTokenStream(pub *mut c_char);