fix(copilot-cli): use semver sort for prerelease tag resolution (#1657)

* Initial plan

* fix(copilot-cli): use semver sort for prerelease tag resolution

* refactor(copilot-cli): extract resolve_prerelease_version function and add test

Extract the prerelease tag resolution logic into a standalone
resolve_prerelease_version() function that can read from stdin for
testing. Add a scenario test that validates version sorting with mock
git ls-remote data to prevent regressions.

* fix(copilot-cli): make repo_url mandatory in resolve_prerelease_version

Remove the stdin/cat fallback and use ${1:?} to error if no URL is
provided. Update the test to mock git via PATH instead of piping stdin.

* Add tests as per review comments without git ls and separate test for prerelease tag

* Further changes in the test and code cleanup

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Kaniska <kaniska244@github.com>

Author: Copilot

src/copilot-cli/devcontainer-feature.json

@@ -1,6 +1,6 @@
 {
     "id": "copilot-cli",
-    "version": "1.1.2",
+    "version": "1.1.3",
     "name": "GitHub Copilot CLI",
     "documentationURL": "https://github.com/devcontainers/features/tree/main/src/copilot-cli",
     "description": "Installs the GitHub Copilot CLI.",

src/copilot-cli/install.sh

@@ -31,6 +31,14 @@ check_packages() {
     fi
 }
 
+resolve_prerelease_version() {
+    local repo_versions="${1:?resolve_prerelease_version requires the copilot-cli repo tags as input}"
+    printf '%s\n' "${repo_versions}" \
+      | awk '{print $2}' | sed 's|refs/tags/||' \
+      | grep -E '^v[0-9]+\.[0-9]+\.[0-9]+(-[0-9]+)?$' \
+      | sort -V | tail -n1
+}
+
 download_from_github() {
     local release_url=$1
     echo "Downloading GitHub Copilot CLI from ${release_url}..."
@@ -63,8 +71,10 @@ install_using_github() {
     if [ "${CLI_VERSION}" = "latest" ]; then
         download_from_github "https://github.com/github/copilot-cli/releases/latest/download/${cli_filename}"
     elif [ "${CLI_VERSION}" = "prerelease" ]; then
-        prerelease_version="$(git ls-remote --tags https://github.com/github/copilot-cli | tail -1 | awk -F/ '{print $NF}')"
+
+        prerelease_version="$(resolve_prerelease_version "$(git ls-remote --tags https://github.com/github/copilot-cli)")"
         download_from_github "https://github.com/github/copilot-cli/releases/download/${prerelease_version}/${cli_filename}"
+        
     else
         # Install specific version
         # Add leading v to version if it doesn't start with v

test/copilot-cli/install_prerelease.sh

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+set -e
+
+# Optional: Import test library
+source dev-container-features-test-lib
+
+# End-to-end check that the "prerelease" channel actually resolves a tag and
+# installs the binary. Regression guard for the inline pipeline in
+# src/copilot-cli/install.sh.
+
+check "copilot binary is on PATH" which copilot
+check "copilot reports a version" bash -c "copilot -v"
+
+# Auto-update flag file must exist for prerelease channel.
+check "auto-update flag created for prerelease" test -f /etc/devcontainer-copilot-cli/auto-update
+
+# Report result
+reportResults

test/copilot-cli/resolve_prerelease_version.sh

@@ -0,0 +1,32 @@
+#!/bin/bash
+
+set -e
+
+# Optional: Import test library
+source dev-container-features-test-lib
+
+resolve_prerelease_version() {
+    local repo_versions="${1:?resolve_prerelease_version requires the copilot-cli repo tags as input}"
+    printf '%s\n' "${repo_versions}" \
+      | awk '{print $2}' | sed 's|refs/tags/||' \
+      | grep -E '^v[0-9]+\.[0-9]+\.[0-9]+(-[0-9]+)?$' \
+      | sort -V | tail -n1
+}
+
+# Tests the tag-resolution pipeline used by src/copilot-cli/install.sh for the
+# "prerelease" channel. 
+
+check "copilot binary is on PATH" which copilot
+check "copilot reports a version" bash -c "copilot -v"
+
+result1="$(resolve_prerelease_version $'abc1234\trefs/tags/v1.0.1\ndef5678\trefs/tags/v1.0.9\nghi9012\trefs/tags/v1.0.10\njkl3456\trefs/tags/v1.0.45\nmno7890\trefs/tags/v1.0.2\n')"
+check "picks highest version (v1.0.45)" bash -c "[ '${result1}' = 'v1.0.45' ]"
+
+result2="$(resolve_prerelease_version $'abc1234\trefs/tags/v1.0.44\ndef5678\trefs/tags/v1.0.45-1\nghi9012\trefs/tags/v1.0.45-10\njkl3456\trefs/tags/v1.0.45-2\nmno7890\trefs/tags/v1.0.45\n')"
+check "picks highest prerelease (v1.0.45-10)" bash -c "[ '${result2}' = 'v1.0.45-10' ]"
+
+result3="$(resolve_prerelease_version $'abc1234\trefs/tags/latest\ndef5678\trefs/tags/v1.0.3\nghi9012\trefs/tags/nightly\njkl3456\trefs/tags/v1.0.20\n')"
+check "picks highest version ignoring non-version tags (v1.0.20)" bash -c "[ '${result3}' = 'v1.0.20' ]"
+
+# Report result
+reportResults

test/copilot-cli/scenarios.json

@@ -0,0 +1,18 @@
+{
+  "resolve_prerelease_version": {
+    "image": "ubuntu:noble",
+    "features": {
+      "copilot-cli": {
+        "version": "latest"
+      }
+    }
+  },
+  "install_prerelease": {
+    "image": "ubuntu:noble",
+    "features": {
+      "copilot-cli": {
+        "version": "prerelease"
+      }
+    }
+  }
+}