If specs are mentioned in the PR, ask to uninstall them before the build

cli/check.py

@@ -1390,6 +1390,20 @@ def check_queue_file(args: argparse.Namespace) -> int:
     return Success
 
 
+def get_requested_specs_from_pr(args):
+    """Get the specs requested in the PR comments."""
+
+    requested_specs = []
+    for reviews in args.pr["reviews"] + args.pr["comments"]:
+        body = reviews["body"]
+        match = re.search(r"--fail-fast ([^ `]+)", body, re.DOTALL)
+        if match:
+            requested_specs.append(match.group(1))
+            print(match.group(1))
+
+    return list(set(requested_specs))
+
+
 def check_and_build(args: argparse.Namespace) -> ExitCode:
     """Check the PR changes and build the packages."""
 
@@ -1414,6 +1428,19 @@ def check_and_build(args: argparse.Namespace) -> ExitCode:
     if args.download:
         return check_all_downloads(specs_to_check)
 
+    requested_specs_from_pr = get_requested_specs_from_pr(args)
+    if requested_specs_from_pr:
+        print("Checking Specs requested in the PR comments to be uninstalled:")
+        installed, findings = find_already_installed(requested_specs_from_pr)
+        print("These specs are already installed:")
+        if installed:
+            print("These specs that are requested in the PR are already installed:")
+            print("\n".join(findings))
+            if args.uninstall:
+                if args.yes or input("Uninstall these requested specs? [y/n]: ").lower() == "y":
+                    for spec in installed:
+                        spack_uninstall_packages([spec])
+
     # Check if specs are already installed and ask if they should be uninstalled.
     # If the user agrees, uninstall the packages.
     installed, _ = find_already_installed(specs_to_check)