Canonicalize the host path passed to --mapdir

lib/cli-compiler/src/utils.rs

@@ -1,7 +1,7 @@
 //! Utility functions for the WebAssembly module
-use anyhow::{bail, Result};
-use std::env;
+use anyhow::{bail, Context, Result};
 use std::path::PathBuf;
+use std::{env, path::Path};
 
 /// Whether or not Wasmer should print with color
 pub fn wasmer_should_print_color() -> bool {
@@ -12,14 +12,18 @@ pub fn wasmer_should_print_color() -> bool {
 }
 
 fn retrieve_alias_pathbuf(alias: &str, real_dir: &str) -> Result<(String, PathBuf)> {
-    let pb = PathBuf::from(&real_dir);
+    let pb = Path::new(real_dir)
+        .canonicalize()
+        .with_context(|| format!("Unable to get the absolute path for \"{real_dir}\""))?;
+
     if let Ok(pb_metadata) = pb.metadata() {
         if !pb_metadata.is_dir() {
-            bail!("\"{}\" exists, but it is not a directory", &real_dir);
+            bail!("\"{real_dir}\" exists, but it is not a directory");
         }
     } else {
-        bail!("Directory \"{}\" does not exist", &real_dir);
+        bail!("Directory \"{real_dir}\" does not exist");
     }
+
     Ok((alias.to_string(), pb))
 }
 

lib/wasix/src/runners/mod.rs

@@ -23,7 +23,10 @@ use crate::runtime::{
 /// instance (the "guest").
 #[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 pub struct MappedDirectory {
+    /// The absolute path for a directory on the host filesystem.
     pub host: std::path::PathBuf,
+    /// The absolute path specifying where the host directory should be mounted
+    /// inside the guest.
     pub guest: String,
 }
 

tests/integration/cli/tests/run_unstable.rs

@@ -1,7 +1,3 @@
-//! Integration tests for `wasmer run2`.
-//!
-//! Note that you will need to manually compile the `wasmer` CLI in release mode
-//! before running any of these tests.
 use std::{
     io::{ErrorKind, Read},
     process::Stdio,
@@ -34,10 +30,10 @@ fn wasmer_run_unstable() -> std::process::Command {
     cmd.arg("run")
         .arg("--quiet")
         .arg("--package=wasmer-cli")
-        .arg("--features=singlepass,cranelift")
+        .arg("--features=singlepass,cranelift,compiler")
         .arg("--color=never")
         .arg("--")
-        .arg("run-unstable");
+        .arg("run");
     cmd.env("RUST_LOG", &*RUST_LOG);
     cmd
 }
@@ -61,6 +57,23 @@ mod webc_on_disk {
         assert.success().stdout(contains("Hello, World!"));
     }
 
+    /// See <https://github.com/wasmerio/wasmer/issues/4010> for more.
+    #[test]
+    fn wasi_runner_mount_using_relative_directory_on_the_host() {
+        let temp = TempDir::new_in(env!("CARGO_TARGET_TMPDIR")).unwrap();
+        std::fs::write(temp.path().join("main.py"), "print('Hello, World!')").unwrap();
+
+        let assert = wasmer_run_unstable()
+            .arg(fixtures::python())
+            .arg("--mapdir=/app:.")
+            .arg("--")
+            .arg("/app/main.py")
+            .current_dir(temp.path())
+            .assert();
+
+        assert.success().stdout(contains("Hello, World!"));
+    }
+
     #[test]
     #[cfg_attr(
         all(target_env = "musl", target_os = "linux"),