subplotlib: Do not override environment entirely

As per the Python template, do not override the full environment

Signed-off-by: Daniel Silverstone <dsilvers@digital-scurf.org>

1 files changed, 7 insertions, 3 deletions

diff --git a/subplotlib/src/steplibrary/runcmd.rs b/subplotlib/src/steplibrary/runcmd.rs
index 7075b68..2bf8c56 100644
--- a/subplotlib/src/steplibrary/runcmd.rs
+++ b/subplotlib/src/steplibrary/runcmd.rs
@@ -46,8 +46,13 @@ impl ContextElement for Runcmd {
         self.env.drain();
         self.paths.drain(..);
         self.env.insert("SHELL".into(), "/bin/sh".into());
-        self.env
-            .insert("PATH".into(), env::join_paths(DEFAULT_PATHS.iter())?);
+        self.env.insert(
+            "PATH".into(),
+            env::var_os("PATH")
+                .map(Ok)
+                .unwrap_or_else(|| env::join_paths(DEFAULT_PATHS.iter()))?,
+        );
+
         // Having assembled the 'default' environment, override it with injected
         // content from the calling environment.
         for (k, v) in env::vars_os() {
@@ -125,7 +130,6 @@ pub fn try_to_run_in(context: &ScenarioContext, dirname: &str, argv0: &str, args
     let mut proc = Command::new(argv0);
     proc.args(&shell_words::split(args)?);
     proc.current_dir(&datadir);
-    proc.env_clear();
     proc.env("HOME", &datadir);
     proc.env("TMPDIR", &datadir);