support RTX_ADD_PATH

This is an env var that poetry/pipenv use to add VIRTUAL_ENV/bin to PATH
while not also creating shims for everything in there.

See #897

Author: jdx

src/cli/direnv/envrc.rs

@@ -41,12 +41,16 @@ impl Envrc {
             writeln!(file, "watch_file {}", cf.to_string_lossy())?;
         }
         for (k, v) in ts.env(&config) {
-            writeln!(
-                file,
-                "export {}={}",
-                shell_escape::unix::escape(k.into()),
-                shell_escape::unix::escape(v.into()),
-            )?;
+            if k == "PATH" {
+                writeln!(file, "PATH_add {}", v)?;
+            } else {
+                writeln!(
+                    file,
+                    "export {}={}",
+                    shell_escape::unix::escape(k.into()),
+                    shell_escape::unix::escape(v.into()),
+                )?;
+            }
         }
         for path in ts.list_paths(&config).into_iter().rev() {
             writeln!(file, "PATH_add {}", path.to_string_lossy())?;

src/cli/hook_env.rs

@@ -1,5 +1,5 @@
 use std::cmp::max;
-use std::env::join_paths;
+use std::env::{join_paths, split_paths};
 use std::ops::Deref;
 use std::path::PathBuf;
 
@@ -41,12 +41,16 @@ impl HookEnv {
             .build(&mut config)?;
         let shell = get_shell(self.shell).expect("no shell provided, use `--shell=zsh`");
         out.stdout.write(hook_env::clear_old_env(&*shell));
-        let env = ts.env(&config);
+        let mut env = ts.env(&config);
+        let env_path = env.remove("PATH");
         let mut diff = EnvDiff::new(&env::PRISTINE_ENV, env);
         let mut patches = diff.to_patches();
 
         let mut paths = config.path_dirs.clone();
         paths.extend(ts.list_paths(&config)); // load the active runtime paths
+        if let Some(p) = env_path {
+            paths.extend(split_paths(&p).collect_vec());
+        }
         diff.path = paths.clone(); // update __RTX_DIFF with the new paths for the next run
 
         patches.extend(self.build_path_operations(&paths, &__RTX_DIFF.path)?);

src/toolset/mod.rs

@@ -287,12 +287,15 @@ impl Toolset {
     }
     pub fn env_with_path(&self, config: &Config) -> BTreeMap<String, String> {
         let mut env = self.env(config);
-        let path_env = self.path_env(config);
+        let mut path_env = self.path_env(config);
+        if let Some(path) = env.get("PATH") {
+            path_env = format!("{}:{}", path, path_env);
+        }
         env.insert("PATH".to_string(), path_env);
         env
     }
     pub fn env(&self, config: &Config) -> BTreeMap<String, String> {
-        let mut entries: BTreeMap<String, String> = self
+        let entries = self
             .list_current_installed_versions(config)
             .into_par_iter()
             .flat_map(|(p, tv)| match p.exec_env(config, self, &tv) {
@@ -302,12 +305,21 @@ impl Toolset {
                     Vec::new()
                 }
             })
-            .collect::<Vec<(String, String)>>()
+            .collect::<Vec<(String, String)>>();
+        let add_paths = entries
+            .iter()
+            .filter(|(k, _)| k == "RTX_ADD_PATH")
+            .map(|(_, v)| v)
+            .join(":");
+        let mut entries: BTreeMap<String, String> = entries
             .into_iter()
             .filter(|(k, _)| k != "RTX_ADD_PATH")
             .filter(|(k, _)| !k.starts_with("RTX_TOOL_OPTS__"))
             .rev()
             .collect();
+        if !add_paths.is_empty() {
+            entries.insert("PATH".to_string(), add_paths);
+        }
         entries.extend(config.env.clone());
         entries
     }