feat(wasm-builder): remap paths to hide username in debug builds (#2865)

utils/wasm-builder/Cargo.toml

@@ -20,6 +20,7 @@ log.workspace = true
 pathdiff.workspace = true
 which.workspace = true
 colored.workspace = true
+dirs.workspace = true
 gmeta.workspace = true
 gear-core.workspace = true
 gear-wasm-instrument.workspace = true

utils/wasm-builder/src/cargo_command.rs

@@ -31,6 +31,7 @@ pub struct CargoCommand {
     target_dir: PathBuf,
     features: Vec<String>,
     toolchain: Toolchain,
+    paths_to_remap: Vec<(PathBuf, &'static str)>,
 }
 
 impl CargoCommand {
@@ -44,6 +45,7 @@ impl CargoCommand {
             target_dir: "target".into(),
             features: vec![],
             toolchain: Toolchain::nightly(),
+            paths_to_remap: vec![],
         }
     }
 
@@ -74,6 +76,13 @@ impl CargoCommand {
         self.toolchain = toolchain;
     }
 
+    /// Set paths to remap.
+    ///
+    /// Used to hide the username from the panic message.
+    pub fn set_paths_to_remap(&mut self, paths_to_remap: &[(PathBuf, &'static str)]) {
+        self.paths_to_remap = paths_to_remap.into();
+    }
+
     /// Execute the `cargo` command with invoking supplied arguments.
     pub fn run(&self) -> Result<()> {
         let mut cargo = Command::new(&self.path);
@@ -101,6 +110,22 @@ impl CargoCommand {
 
         self.remove_cargo_encoded_rustflags(&mut cargo);
 
+        if !self.paths_to_remap.is_empty() {
+            // `--remap-path-prefix` is used to remove username from panic messages
+            // https://doc.rust-lang.org/rustc/command-line-arguments.html#--remap-path-prefix-remap-source-names-in-output
+            let global_encoded_rustflags = self
+                .paths_to_remap
+                .iter()
+                .map(|(from, to)| format!("--remap-path-prefix={from}={to}", from = from.display()))
+                .collect::<Vec<_>>()
+                .join("\x1f");
+
+            // The environment variable `CARGO_ENCODED_RUSTFLAGS` is used to globally remap path prefix.
+            // It is also separated by `\x1f` to support folders with spaces or any unusual characters.
+            // Unlike `cargo rust`, this is useful for passing flags to all dependencies (i.e. globally).
+            cargo.env("CARGO_ENCODED_RUSTFLAGS", global_encoded_rustflags);
+        }
+
         let status = cargo.status().context("unable to execute cargo command")?;
         ensure!(
             status.success(),

utils/wasm-builder/src/lib.rs

@@ -17,10 +17,14 @@
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
 use crate::{cargo_command::CargoCommand, cargo_toolchain::Toolchain, wasm_project::WasmProject};
-use anyhow::Result;
+use anyhow::{Context, Result};
 use gmeta::{Metadata, MetadataRepr};
 use regex::Regex;
-use std::{env, path::Path, process};
+use std::{
+    env,
+    path::{Path, PathBuf},
+    process,
+};
 use wasm_project::ProjectType;
 
 mod builder_error;
@@ -103,6 +107,9 @@ impl WasmBuilder {
         let profile = if profile == "debug" { "dev" } else { profile };
         self.cargo.set_profile(profile.to_string());
         self.cargo.set_features(&self.enabled_features()?);
+        if profile != "dev" {
+            self.cargo.set_paths_to_remap(&self.paths_to_remap()?);
+        }
 
         self.cargo.run()?;
         self.wasm_project.postprocess()
@@ -159,6 +166,25 @@ impl WasmBuilder {
         }
         Ok(matched_features)
     }
+
+    fn paths_to_remap(&self) -> Result<Vec<(PathBuf, &'static str)>> {
+        let home_dir = dirs::home_dir().context("unable to get home directory")?;
+
+        let project_dir = self.wasm_project.original_dir();
+
+        let cargo_dir = std::env::var_os("CARGO_HOME")
+            .map(PathBuf::from)
+            .context("unable to get cargo home directory")?;
+
+        let cargo_checkouts_dir = cargo_dir.join("git").join("checkouts");
+
+        Ok(vec![
+            (home_dir, "/home"),
+            (project_dir, "/code"),
+            (cargo_dir, "/cargo"),
+            (cargo_checkouts_dir, "/deps"),
+        ])
+    }
 }
 
 impl Default for WasmBuilder {

utils/wasm-builder/src/wasm_project.rs

@@ -120,6 +120,11 @@ impl WasmProject {
         self.out_dir.join("Cargo.toml")
     }
 
+    /// Return the path to the original project directory.
+    pub fn original_dir(&self) -> PathBuf {
+        self.original_dir.clone()
+    }
+
     /// Return the path to the target directory.
     pub fn target_dir(&self) -> PathBuf {
         self.target_dir.clone()