fix(plugins): enforce rustc compatibility

BREAKING CHANGE: API v4+ plugin packages must declare the exact rustc version used to build the binary.

Refs #901

crates/ocs_plugin_api/ARCHITECTURE.md

@@ -54,7 +54,7 @@ The runtime enforces three gates:
 
 1. `ocs_plugin_api_version()` exported by the cdylib must be within `[API_VERSION_MIN_SUPPORTED, effective_max_api_version()]`.
 2. For v4+, `acadrust_sources_compatible(host_acadrust_source(), plugin_acadrust_source)` must be true.
-3. For v4+, when the plugin declares `rustc_version`, `rustc_versions_compatible(host_rustc_version(), plugin_rustc_version)` must be true.
+3. For v4+, the plugin must declare `rustc_version`, and `rustc_versions_compatible(host_rustc_version(), plugin_rustc_version)` must be true.
 
 ---
 

crates/ocs_plugin_api/build.rs

@@ -384,7 +384,8 @@ fn generate_version_info(out_dir: &Path) {
         .find(|p| p.name.as_str() == "acadrust")
         .expect("acadrust package in Cargo.lock");
 
-    let rustc_version = Command::new("rustc")
+    let rustc = env::var_os("RUSTC").unwrap_or_else(|| "rustc".into());
+    let rustc_version = Command::new(rustc)
         .arg("--version")
         .output()
         .ok()

docs/plugin-architecture.md

@@ -99,10 +99,10 @@ affect whether a prebuilt plugin can safely be loaded:
 - `rustc_version` — the output of `rustc --version` for the compiler that built
   the host.
 
-A plugin's `plugin.toml` may declare the same values under `[opencad]`. When
-either is declared, the host refuses to load the plugin unless it matches the
-host exactly. This turns the current silent runner crash into a one-line
-diagnosis such as:
+A plugin's `plugin.toml` declares the same values under `[opencad]`. For API v4
+and later, `rustc_version` is required and the host refuses to load the plugin
+unless it matches exactly. This turns the current silent runner crash into a
+one-line diagnosis such as:
 
 ```
 Plugin built with rustc 1.96.0, host requires 1.98.0 - rebuild required
@@ -229,12 +229,12 @@ version = "0.1.0"
 description = "…"
 
 [opencad]
-api_version = 3
+api_version = 4
 ribbon_order = 50
 command_prefixes = ["EX_"]
 xdata_apps = []
-# For API v4+, also record the exact rustc used to build the release asset.
-# rustc_version = "rustc 1.98.0 (hash date)"
+# Filled with the exact compiler output while staging the release asset.
+rustc_version = "rustc 1.98.0 (hash date)"
 ```
 
 The full, buildable scaffold is in [`docs/plugin-template/`](plugin-template);

docs/plugin-template/.github/workflows/release.yml

@@ -36,7 +36,7 @@ jobs:
         run: |
           mkdir -p dist
           cp target/release/*.${{ matrix.ext }} "dist/${{ matrix.asset }}"
-          cp plugin.toml dist/plugin.toml
+          sed "s|__RUSTC_VERSION__|$(rustc --version)|" plugin.toml > dist/plugin.toml
       - uses: softprops/action-gh-release@v2
         with:
           files: |

docs/plugin-template/README.md

@@ -28,7 +28,8 @@ folder into a new repo and rename the placeholders.
 cargo build --release
 mkdir -p "<config>/OpenCADStudio/plugins/opencad.my_plugin"
 cp target/release/*my_plugin*.so "<config>/OpenCADStudio/plugins/opencad.my_plugin/"
-cp plugin.toml                    "<config>/OpenCADStudio/plugins/opencad.my_plugin/"
+sed "s|__RUSTC_VERSION__|$(rustc --version)|" plugin.toml > \
+  "<config>/OpenCADStudio/plugins/opencad.my_plugin/plugin.toml"
 ```
 
 Restart Open CAD Studio: the ribbon tab appears and `MP_` commands route to your

docs/plugin-template/plugin.toml

@@ -8,7 +8,8 @@ license = "GPL-3.0-only"
 repository = "your-account/your-plugin-repo"
 
 [opencad]
-api_version = 3
+api_version = 4
+rustc_version = "__RUSTC_VERSION__"
 ribbon_order = 60
 command_prefixes = ["MP_"]
 xdata_apps = ["MYPLUGIN_RECORD"]

src/plugin/external.rs

@@ -100,9 +100,6 @@ impl ExternalPlugin {
         if !ocs_plugin_api::version_info::uses_acadrust_gate(self.api_version) {
             return true;
         }
-        if !self.rustc_declared {
-            return true;
-        }
         match self.rustc_version.as_deref() {
             None | Some("") => false,
             Some(version) => ocs_plugin_api::version_info::rustc_versions_compatible(
@@ -534,7 +531,7 @@ xdata_apps = ["MYPLUGIN_RECORD"]
     }
 
     #[test]
-    fn undeclared_rustc_falls_back_to_api_gate() {
+    fn undeclared_rustc_is_incompatible() {
         let toml = r#"
 [plugin]
 id = "opencad.test"
@@ -545,7 +542,8 @@ api_version = 4
         let p = parse_plugin_toml(toml).expect("parsed");
         assert!(!p.rustc_declared);
         assert!(p.rustc_version.is_none());
-        assert!(p.rustc_compatible(), "undeclared rustc is treated as compatible");
+        assert!(!p.rustc_compatible());
+        assert!(!p.loadable());
     }
 
     #[test]

src/plugin/marketplace.rs

@@ -242,8 +242,6 @@ pub fn fetch_release_info(repo: &str) -> Result<Vec<ReleaseInfo>, String> {
                 manifest.api_version,
             ) {
                 true
-            } else if !rustc_declared {
-                true
             } else {
                 match rustc_version.as_deref() {
                     None | Some("") => false,
@@ -281,17 +279,6 @@ pub fn fetch_release_info(repo: &str) -> Result<Vec<ReleaseInfo>, String> {
             }
         }
     }
-    let any_rustc_declared = info.iter().any(|r| r.rustc_declared);
-    if any_rustc_declared {
-        for r in &mut info {
-            if !r.rustc_declared
-                && ocs_plugin_api::version_info::uses_acadrust_gate(r.api_version)
-            {
-                r.rustc_compatible = false;
-            }
-        }
-    }
-
     if info.is_empty() {
         Err(last_error.unwrap_or_else(|| "no installable releases found".to_string()))
     } else {
@@ -391,18 +378,12 @@ pub fn install(release: &Release, repository: &str) -> Result<String, String> {
         }
     }
 
-    if ocs_plugin_api::version_info::uses_acadrust_gate(manifest.api_version)
-        && manifest.rustc_declared
-    {
+    if ocs_plugin_api::version_info::uses_acadrust_gate(manifest.api_version) {
         let Some(version) = manifest.rustc_version.as_deref() else {
-            return Err(
-                "Release declares rustc metadata but has no version; cannot verify ABI compatibility".to_string(),
-            );
+            return Err("Release has no rustc version; cannot verify ABI compatibility".to_string());
         };
         if version.is_empty() {
-            return Err(
-                "Release declares rustc metadata but has no version; cannot verify ABI compatibility".to_string(),
-            );
+            return Err("Release has no rustc version; cannot verify ABI compatibility".to_string());
         }
         if !ocs_plugin_api::version_info::rustc_versions_compatible(
             version,

src/ui/window/plugin_manager.rs

@@ -226,7 +226,8 @@ fn external_card<'a>(
 ) -> Element<'a, Message> {
     let failed_old_api = load_error.is_some() && !p.api_compatible();
     let acadrust_mismatch = p.acadrust_declared && !p.acadrust_compatible();
-    let rustc_mismatch = p.rustc_declared && !p.rustc_compatible();
+    let rustc_mismatch = ocs_plugin_api::version_info::uses_acadrust_gate(p.api_version)
+        && !p.rustc_compatible();
     let (status, kind) = if loaded && disabled {
         (t!("Disabled"), StatusKind::Muted)
     } else if loaded {