Capture the rustc environment and project it into run (#4421)

packages/cli/src/build/builder.rs

@@ -1,6 +1,6 @@
 use crate::{
     serve::WebServer, BuildArtifacts, BuildRequest, BuildStage, BuilderUpdate, Platform,
-    ProgressRx, ProgressTx, Result, StructuredOutput,
+    ProgressRx, ProgressTx, Result, RustcArgs, StructuredOutput,
 };
 use anyhow::{bail, Context};
 use dioxus_cli_opt::process_file_to;
@@ -429,41 +429,50 @@ impl AppBuilder {
     }
 
     /// Create a list of environment variables that the child process will use
+    ///
+    /// We try to emulate running under `cargo` as much as possible, carrying over vars like `CARGO_MANIFEST_DIR`.
+    /// Previously, we didn't want to emulate this behavior, but now we do in order to be a good
+    /// citizen of the Rust ecosystem and allow users to use `cargo` features like `CARGO_MANIFEST_DIR`.
+    ///
+    /// Note that Dioxus apps *should not* rely on this vars being set, but libraries like Bevy do.
     pub(crate) fn child_environment_variables(
         &mut self,
         devserver_ip: Option<SocketAddr>,
         start_fullstack_on_address: Option<SocketAddr>,
         always_on_top: bool,
         build_id: BuildId,
-    ) -> Vec<(&'static str, String)> {
+    ) -> Vec<(String, String)> {
         let krate = &self.build;
 
         // Set the env vars that the clients will expect
         // These need to be stable within a release version (ie 0.6.0)
-        let mut envs = vec![
+        let mut envs: Vec<(String, String)> = vec![
-            (dioxus_cli_config::CLI_ENABLED_ENV, "true".to_string()),
             (
-                dioxus_cli_config::APP_TITLE_ENV,
+                dioxus_cli_config::CLI_ENABLED_ENV.into(),
+                "true".to_string(),
+            ),
+            (
+                dioxus_cli_config::APP_TITLE_ENV.into(),
                 krate.config.web.app.title.clone(),
             ),
             (
-                dioxus_cli_config::SESSION_CACHE_DIR,
+                dioxus_cli_config::SESSION_CACHE_DIR.into(),
                 self.build.session_cache_dir().display().to_string(),
             ),
-            (dioxus_cli_config::BUILD_ID, build_id.0.to_string()),
+            (dioxus_cli_config::BUILD_ID.into(), build_id.0.to_string()),
             (
-                dioxus_cli_config::ALWAYS_ON_TOP_ENV,
+                dioxus_cli_config::ALWAYS_ON_TOP_ENV.into(),
                 always_on_top.to_string(),
             ),
         ];
 
         if let Some(devserver_ip) = devserver_ip {
             envs.push((
-                dioxus_cli_config::DEVSERVER_IP_ENV,
+                dioxus_cli_config::DEVSERVER_IP_ENV.into(),
                 devserver_ip.ip().to_string(),
             ));
             envs.push((
-                dioxus_cli_config::DEVSERVER_PORT_ENV,
+                dioxus_cli_config::DEVSERVER_PORT_ENV.into(),
                 devserver_ip.port().to_string(),
             ));
         }
@@ -473,22 +482,42 @@ impl AppBuilder {
             .map(|f| f.verbose)
             .unwrap_or_default()
         {
-            envs.push(("RUST_BACKTRACE", "1".to_string()));
+            envs.push(("RUST_BACKTRACE".into(), "1".to_string()));
         }
 
         if let Some(base_path) = krate.base_path() {
-            envs.push((dioxus_cli_config::ASSET_ROOT_ENV, base_path.to_string()));
+            envs.push((
+                dioxus_cli_config::ASSET_ROOT_ENV.into(),
+                base_path.to_string(),
+            ));
         }
 
         if let Some(env_filter) = env::var_os("RUST_LOG").and_then(|e| e.into_string().ok()) {
-            envs.push(("RUST_LOG", env_filter));
+            envs.push(("RUST_LOG".into(), env_filter));
         }
 
         // Launch the server if we were given an address to start it on, and the build includes a server. After we
         // start the server, consume its stdout/stderr.
         if let Some(addr) = start_fullstack_on_address {
-            envs.push((dioxus_cli_config::SERVER_IP_ENV, addr.ip().to_string()));
+            envs.push((
-            envs.push((dioxus_cli_config::SERVER_PORT_ENV, addr.port().to_string()));
+                dioxus_cli_config::SERVER_IP_ENV.into(),
+                addr.ip().to_string(),
+            ));
+            envs.push((
+                dioxus_cli_config::SERVER_PORT_ENV.into(),
+                addr.port().to_string(),
+            ));
+        }
+
+        // If there's any CARGO vars in the rustc_wrapper files, push those too
+        if let Ok(res) = std::fs::read_to_string(self.build.rustc_wrapper_args_file.path()) {
+            if let Ok(res) = serde_json::from_str::<RustcArgs>(&res) {
+                for (key, value) in res.envs {
+                    if key.starts_with("CARGO_") {
+                        envs.push((key, value));
+                    }
+                }
+            }
         }
 
         envs
@@ -794,7 +823,7 @@ impl AppBuilder {
     /// paths right now, but they will when we start to enable things like swift integration.
     ///
     /// Server/liveview/desktop are all basically the same, though
-    fn open_with_main_exe(&mut self, envs: Vec<(&str, String)>, args: &[String]) -> Result<()> {
+    fn open_with_main_exe(&mut self, envs: Vec<(String, String)>, args: &[String]) -> Result<()> {
         let main_exe = self.app_exe();
 
         tracing::debug!("Opening app with main exe: {main_exe:?}");
@@ -802,7 +831,6 @@ impl AppBuilder {
         let mut child = Command::new(main_exe)
             .args(args)
             .envs(envs)
-            .env_remove("CARGO_MANIFEST_DIR") // running under `dx` shouldn't expose cargo-only :
             .stderr(Stdio::piped())
             .stdout(Stdio::piped())
             .kill_on_drop(true)
@@ -839,7 +867,7 @@ impl AppBuilder {
     ///
     /// TODO(jon): we should probably check if there's a simulator running before trying to install,
     /// and open the simulator if we have to.
-    async fn open_ios_sim(&mut self, envs: Vec<(&str, String)>) -> Result<()> {
+    async fn open_ios_sim(&mut self, envs: Vec<(String, String)>) -> Result<()> {
         tracing::debug!("Installing app to simulator {:?}", self.build.root_dir());
 
         let res = Command::new("xcrun")
@@ -865,7 +893,6 @@ impl AppBuilder {
             .arg("booted")
             .arg(self.build.bundle_identifier())
             .envs(ios_envs)
-            .env_remove("CARGO_MANIFEST_DIR")
             .stderr(Stdio::piped())
             .stdout(Stdio::piped())
             .kill_on_drop(true)
@@ -1209,7 +1236,7 @@ We checked the folders:
         &self,
         root: bool,
         devserver_socket: SocketAddr,
-        envs: Vec<(&'static str, String)>,
+        envs: Vec<(String, String)>,
     ) -> Result<()> {
         let apk_path = self.build.debug_apk_path();
         let session_cache = self.build.session_cache_dir();

packages/cli/src/build/request.rs

@@ -415,7 +415,11 @@ pub(crate) struct BuildRequest {
 #[derive(Clone, Debug, PartialEq)]
 pub enum BuildMode {
     /// A normal build generated using `cargo rustc`
-    Base,
+    ///
+    /// "run" indicates whether this build is intended to be run immediately after building.
+    /// This means we try to capture the build environment, saving vars like `CARGO_MANIFEST_DIR`
+    /// for the running executable.
+    Base { run: bool },
 
     /// A "Fat" build generated with cargo rustc and dx as a custom linker without -Wl,-dead-strip
     Fat,
@@ -810,7 +814,7 @@ impl BuildRequest {
                     .await?;
             }
 
-            BuildMode::Base | BuildMode::Fat => {
+            BuildMode::Base { .. } | BuildMode::Fat => {
                 ctx.status_start_bundle();
 
                 self.write_executable(ctx, &artifacts.exe, &mut artifacts.assets)
@@ -2165,7 +2169,7 @@ impl BuildRequest {
                     .args(args)
                     .envs(env.iter().map(|(k, v)| (k.as_ref(), v)));
 
-                if ctx.mode == BuildMode::Fat {
+                if matches!(ctx.mode, BuildMode::Fat | BuildMode::Base { run: true }) {
                     cmd.env(
                         DX_RUSTC_WRAPPER_ENV_VAR,
                         dunce::canonicalize(self.rustc_wrapper_args_file.path())
@@ -4166,7 +4170,7 @@ __wbg_init({{module_or_path: "/{}/{wasm_path}"}}).then((wasm) => {{
     ///
     /// This might stop working if/when cargo stabilizes contents-based fingerprinting.
     fn bust_fingerprint(&self, ctx: &BuildContext) -> Result<()> {
-        if matches!(ctx.mode, BuildMode::Fat) {
+        if matches!(ctx.mode, BuildMode::Fat | BuildMode::Base { run: true }) {
             // `dx` compiles everything with `--target` which ends up with a structure like:
             // target/<triple>/<profile>/.fingerprint/<package_name>-<hash>
             //

packages/cli/src/cli/build.rs

@@ -70,7 +70,7 @@ impl CommandWithPlatformOverrides<BuildArgs> {
         let ssg = self.shared.ssg;
         let targets = self.into_targets().await?;
 
-        AppBuilder::started(&targets.client, BuildMode::Base)?
+        AppBuilder::started(&targets.client, BuildMode::Base { run: false })?
             .finish_build()
             .await?;
 
@@ -78,7 +78,7 @@ impl CommandWithPlatformOverrides<BuildArgs> {
 
         if let Some(server) = targets.server.as_ref() {
             // If the server is present, we need to build it as well
-            let mut server_build = AppBuilder::started(server, BuildMode::Base)?;
+            let mut server_build = AppBuilder::started(server, BuildMode::Base { run: false })?;
             server_build.finish_build().await?;
 
             // Run SSG and cache static routes

packages/cli/src/cli/bundle.rs

@@ -39,7 +39,7 @@ impl Bundle {
 
         let BuildTargets { client, server } = self.args.into_targets().await?;
 
-        AppBuilder::started(&client, BuildMode::Base)?
+        AppBuilder::started(&client, BuildMode::Base { run: false })?
             .finish_build()
             .await?;
 
@@ -47,7 +47,7 @@ impl Bundle {
 
         if let Some(server) = server.as_ref() {
             // If the server is present, we need to build it as well
-            AppBuilder::started(server, BuildMode::Base)?
+            AppBuilder::started(server, BuildMode::Base { run: false })?
                 .finish_build()
                 .await?;
 

packages/cli/src/serve/mod.rs

@@ -198,7 +198,7 @@ pub(crate) async fn serve_all(args: ServeArgs, tracer: &mut TraceController) ->
                                 }
                             }
                         }
-                        BuildMode::Base | BuildMode::Fat => {
+                        BuildMode::Base { .. } | BuildMode::Fat => {
                             _ = builder
                                 .open(&bundle, &mut devserver)
                                 .await

packages/cli/src/serve/runner.rs

@@ -227,7 +227,7 @@ impl AppServer {
     pub(crate) fn initialize(&mut self) {
         let build_mode = match self.use_hotpatch_engine {
             true => BuildMode::Fat,
-            false => BuildMode::Base,
+            false => BuildMode::Base { run: true },
         };
 
         self.client.start(build_mode.clone());
@@ -495,9 +495,9 @@ impl AppServer {
                 self.clear_cached_rsx();
                 server.send_patch_start().await;
             } else {
-                self.client.start_rebuild(BuildMode::Base);
+                self.client.start_rebuild(BuildMode::Base { run: true });
                 if let Some(server) = self.server.as_mut() {
-                    server.start_rebuild(BuildMode::Base);
+                    server.start_rebuild(BuildMode::Base { run: true });
                 }
                 self.clear_hot_reload_changes();
                 self.clear_cached_rsx();
@@ -680,7 +680,7 @@ impl AppServer {
     pub(crate) async fn full_rebuild(&mut self) {
         let build_mode = match self.use_hotpatch_engine {
             true => BuildMode::Fat,
-            false => BuildMode::Base,
+            false => BuildMode::Base { run: true },
         };
 
         self.client.start_rebuild(build_mode.clone());