copilot: Install pants lazily (#3253)

Signed-off-by: Ryan Northey <[email protected]>
Co-authored-by: copilot-swe-agent[bot] <[email protected]>

Author: Copilot

.github/workflows/copilot-setup-steps.yml

@@ -90,6 +90,7 @@ jobs:
         python-version: "3.12"
     - name: Pants
       run: |
-        ./get-pants.sh
+        # Install the pants wrapper script that auto-installs pants if needed
+        sudo cp pants-wrapper.sh /usr/local/bin/pants
+        sudo chmod +x /usr/local/bin/pants
         echo "PANTS_CA_CERTS_PATH=/etc/ssl/certs/ca-certificates.crt" >> $GITHUB_ENV
-        pants --version

pants-wrapper.sh

@@ -0,0 +1,56 @@
+#!/usr/bin/env bash
+# Pants wrapper script that auto-installs pants if not already available
+#
+# This wrapper is installed to /usr/local/bin/pants during Copilot setup.
+# It allows users to just run "pants" without worrying about installation.
+#
+# How it works:
+# 1. Check if pants is already installed in ~/.local/bin (default install location)
+# 2. If not, automatically run get-pants.sh to install it
+# 3. Then execute pants with all arguments passed through
+#
+# This means users can always run "pants <args>" and it will "just work"
+
+set -euo pipefail
+
+GET_PANTS="${GET_PANTS:-}"
+
+
+run_pants () {
+    if [[ -x "$HOME/.local/bin/pants" ]]; then
+        exec "$HOME/.local/bin/pants" "$@"
+        exit 0
+    fi
+}
+
+find_get_pants () {
+    if [[ -z "$GET_PANTS" ]]; then
+        # Try to find get-pants.sh
+        if [[ -f "get-pants.sh" ]]; then
+            GET_PANTS="$(realpath ./get-pants.sh)"
+        elif [[ -f "../get-pants.sh" ]]; then
+            GET_PANTS="$(realpath ../get-pants.sh)"
+        elif [[ -f "/home/runner/work/toolshed/toolshed/get-pants.sh" ]]; then
+            GET_PANTS="/home/runner/work/toolshed/toolshed/get-pants.sh"
+        else
+            echo "Error: Cannot find get-pants.sh. Please set GET_PANTS or run from repository directory." >&2
+            exit 1
+        fi
+    fi
+    if [[ ! -f "$GET_PANTS" ]]; then
+        echo "Error: Cannot find get-pants.sh (${GET_PANTS})." >&2
+    fi
+}
+
+install_pants () {
+    echo "Pants not found. Installing pants..." >&2
+    find_get_pants
+    echo "Running get-pants.sh from $GET_PANTS..." >&2
+    "${GET_PANTS}"
+}
+
+run_pants "${@}"
+install_pants
+run_pants "${@}"
+echo "Error: pants installation failed" >&2
+exit 1