Add -k <query> to checkout PR by search query

build_pr_changes.py

@@ -571,6 +571,33 @@ def add_compiler_to_specs(specs_to_check, args) -> List[str]:
     return specs_to_check
 
 
+def checkout_pr_by_search_query(args: argparse.Namespace) -> ExitCode:
+    """Checkout the PR branch by searching for the PR number."""
+    if not args.checkout:
+        return Success
+
+    # Find the PR number from the PR query:
+    query = f"gh pr list --limit 1 -S '{args.checkout}' --json number -q.[].number"
+    print("Querying for the PR to check out, please wait a second or so:")
+    exitcode, number = subprocess.getstatusoutput(query)
+    if exitcode != 0 or not number:
+        print(f"Failed to find the PR by querying for '{args.checkout}'\n" + number)
+        return exitcode or 1
+    # View the information about the PR:
+    exitcode, output = subprocess.getstatusoutput(f"gh pr view {number}")
+    if exitcode != 0:
+        print("Failed to view the PR:", output)
+        return exitcode
+    print(f'Found PR for "{args.checkout}":')
+    print(output)
+    # Checkout the PR branch:
+    exitcode, output = subprocess.getstatusoutput(f"gh pr checkout {number}")
+    if exitcode != 0:
+        print("Failed to checkout the PR branch:", output)
+        return exitcode
+    return Success
+
+
 def parse_args() -> argparse.Namespace:
     """Run spack install on recipes changed in the current branch from develop."""
     basicConfig(format="%(message)s", level=INFO)
@@ -605,6 +632,12 @@ def parse_args() -> argparse.Namespace:
         "--dependencies",
         help="Additional dependency specs for the packages.",
     )
+    argparser.add_argument(
+        "-k",
+        "--checkout",
+        help="Checkout the PR branch (find it by PR query) to check the changes.",
+        type=str,
+    )
     argparser.add_argument(
         "-l", "--label-success", action="store_true", help="Label the PR on success."
     )
@@ -634,6 +667,10 @@ def main(args) -> int:
     # - Add support for installing the packages in a container, sandbox, or remote host.
     #   Use pxssh module of pexpect: https://pexpect.readthedocs.io/en/stable/api/pxssh.html
 
+    exitcode = checkout_pr_by_search_query(args)
+    if exitcode != Success:
+        return exitcode
+
     # Get the number of the current PR:
     # In case we shall approve/merge, we need the PR number so we don't approve/merge the wrong PR.
     exitcode, output = subprocess.getstatusoutput("gh pr view --json number -q .number")