fix target dir test

Author: jyn514

crates/rust-analyzer/src/config.rs

@@ -3798,8 +3798,10 @@ mod tests {
         (config, _, _) = config.apply_change(change);
 
         assert_eq!(config.cargo_targetDir(None), &Some(TargetDirectory::UseSubdirectory(true)));
+        let target =
+            Utf8PathBuf::from(std::env::var("CARGO_TARGET_DIR").unwrap_or("target".to_string()));
         assert!(
-            matches!(config.flycheck(None), FlycheckConfig::CargoCommand { options, .. } if options.target_dir == Some(Utf8PathBuf::from("target/rust-analyzer")))
+            matches!(config.flycheck(None), FlycheckConfig::CargoCommand { options, .. } if options.target_dir == Some(target.join("rust-analyzer")))
         );
     }
 

crates/test-utils/src/lib.rs

@@ -396,12 +396,19 @@ pub fn skip_slow_tests() -> bool {
     if should_skip {
         eprintln!("ignoring slow test");
     } else {
-        let path = project_root().join("./target/.slow_tests_cookie");
+        let path = target_dir().join(".slow_tests_cookie");
         fs::write(path, ".").unwrap();
     }
     should_skip
 }
 
+pub fn target_dir() -> Utf8PathBuf {
+    match std::env::var("CARGO_TARGET_DIR") {
+        Ok(target) => Utf8PathBuf::from(target),
+        Err(_) => project_root().join("target"),
+    }
+}
+
 /// Returns the path to the root directory of `rust-analyzer` project.
 pub fn project_root() -> Utf8PathBuf {
     let dir = env!("CARGO_MANIFEST_DIR");