fix(tool-stub): keep env_with_path instead of rebuilding PATH

e2e/cli/test_tool_stub_preserves_caller_path_slow

@@ -0,0 +1,82 @@
+#!/usr/bin/env bash
+# shellcheck disable=SC2103
+#
+# tool-stub non-cached exec must:
+# 1. Keep project _.path dirs so sibling stubs remain LookPath-able
+# 2. Prefer the stub-selected tool version over an outer task's tool bins
+
+export MISE_GPG_VERIFY=false
+
+mkdir -p tool_stub_preserves_caller_path/bin
+cd tool_stub_preserves_caller_path
+
+# --- _.path sibling stubs remain visible ------------------------------------
+
+cat >mise.toml <<'EOF'
+[env]
+_.path = ["./bin"]
+
+[tasks.check]
+run = "dummy"
+EOF
+
+cat >bin/dummy <<'EOF'
+#!/usr/bin/env -S mise tool-stub
+tool = "dummy"
+version = "1.0.0"
+EOF
+chmod +x bin/dummy
+
+cat >bin/sibling <<'EOF'
+#!/usr/bin/env bash
+echo sibling-found
+EOF
+chmod +x bin/sibling
+
+# Install via stub (also writes tool-stub bin-path cache)
+assert_contains "mise run check" "This is Dummy"
+
+# Replace the installed binary with a PATH probe. Keep the tool installed so the
+# next stub run skips install but still hits execute_with_tool_request after the
+# bin-path cache is cleared (not the inherit-PATH short-circuit).
+DUMMY_BIN="$MISE_DATA_DIR/installs/dummy/1.0.0/bin/dummy"
+cat >"$DUMMY_BIN" <<'EOF'
+#!/usr/bin/env bash
+set -euo pipefail
+command -v sibling
+EOF
+chmod +x "$DUMMY_BIN"
+
+rm -rf "$MISE_CACHE_DIR/tool-stubs"
+
+assert_contains "mise run check" "sibling"
+
+# --- stub-selected version wins over outer toolset --------------------------
+
+mkdir -p ../tool_stub_no_shadow/bin
+cd ../tool_stub_no_shadow
+
+cat >mise.toml <<'EOF'
+[tools]
+dummy = "1.0.0"
+
+[env]
+_.path = ["./bin"]
+
+[tasks.check]
+run = "dummy"
+EOF
+
+cat >bin/dummy <<'EOF'
+#!/usr/bin/env -S mise tool-stub
+tool = "dummy"
+version = "2.0.0"
+EOF
+chmod +x bin/dummy
+
+mise install dummy@1.0.0 dummy@2.0.0
+rm -rf "$MISE_CACHE_DIR/tool-stubs"
+
+# Outer task activates dummy@1.0.0; stub selects 2.0.0 — must not resolve 1.0.0
+assert_contains "mise run check" "This is Dummy 2.0.0"
+assert_not_contains "mise run check" "This is Dummy 1.0.0"

src/cli/tool_stub.rs

@@ -566,25 +566,28 @@ async fn execute_with_tool_request(
     // Find the binary path using cache
     match find_cached_or_resolve_bin_path(&toolset, &*config, stub, stub_path).await? {
         Ok(bin_path) => {
-            // Get the environment with proper PATH from toolset
+            // env_with_path already has _.path and filters outer install dirs.
+            // Prepend backend dependency bins (e.g. node for npm); see #7777.
             let mut env = toolset.env_with_path(config).await?;
-            let mut path_env = crate::path_env::PathEnv::from_iter(crate::env::PATH.clone());
-            for p in toolset.list_paths(config).await {
-                path_env.add(p);
-            }
-
             if let Some((backend, _tv)) = toolset.list_current_installed_versions(config).first() {
-                let btp = backend
+                let dep_paths = backend
                     .dependency_toolset(config)
                     .await?
                     .list_paths(config)
                     .await;
-                for p in btp {
-                    path_env.add(p);
+                if !dep_paths.is_empty() {
+                    let path = env
+                        .get(crate::env::PATH_KEY.as_str())
+                        .cloned()
+                        .unwrap_or_default();
+                    let mut paths = dep_paths;
+                    paths.extend(std::env::split_paths(&path));
+                    env.insert(
+                        crate::env::PATH_KEY.to_string(),
+                        std::env::join_paths(paths)?.to_string_lossy().to_string(),
+                    );
                 }
             }
-            env.insert(crate::env::PATH_KEY.to_string(), path_env.to_string());
-
             crate::cli::exec::exec_program(bin_path, args, env, &Default::default(), false).await
         }
         Err(e) => match e {