Check for backports if pr has label

nixprstatus/pr.py

@@ -5,6 +5,7 @@ DEFAULT_HEADERS = {
     "Accept": "application/vnd.github.text+json",
 }
 DEFAULT_BRANCHES = ["master", "nixos-unstable-small", "nixos-unstable", "nixos-24.05"]
+BACKPORT_LABEL = "backport release-24.05"
 
 
 class PRStatus(BaseModel):
@@ -31,7 +32,9 @@ def commits_since(first_ref: str, last_ref: str) -> int:
     return commit_response.json()["behind_by"]
 
 
-def pr_merge_status(pr: int, branches: list[str] = DEFAULT_BRANCHES) -> PRStatus:
+def pr_merge_status(
+    pr: int, branches: list[str] = DEFAULT_BRANCHES, check_backport: bool = True
+) -> PRStatus:
     url = f"https://api.github.com/repos/NixOS/nixpkgs/pulls/{pr}"
     pr_response = requests.get(url, headers=DEFAULT_HEADERS)
     pr_response.raise_for_status()
@@ -44,10 +47,41 @@ def pr_merge_status(pr: int, branches: list[str] = DEFAULT_BRANCHES) -> PRStatus
 
     commit_sha = pr_data.get("merge_commit_sha")
 
+    # Check for backport label
+    has_backport_label = BACKPORT_LABEL in [
+        label.get("name") for label in pr_data["labels"]
+    ]
+
     results = {}
 
     for branch in branches:
         in_branch = commit_in_branch(commit_sha, branch)
         results[branch] = in_branch
 
+    if check_backport and has_backport_label and "nixos-24.05" in branches:
+        # Check comments for message about backport
+        comment_url = f"https://api.github.com/repos/NixOS/nixpkgs/issues/{pr}/comments"
+        comment_response = requests.get(comment_url, headers=DEFAULT_HEADERS)
+        comment_response.raise_for_status()
+
+        for comment in comment_response.json():
+            body = comment.get("body_text", "")
+            if "Successfully created backport PR" in body:
+                backport_pr = body.split("\n")[-1].replace("#", "")
+
+                # Check if backport pr has been merged
+                backport_url = (
+                    f"https://api.github.com/repos/NixOS/nixpkgs/pulls/{backport_pr}"
+                )
+                backport_response = requests.get(backport_url, headers=DEFAULT_HEADERS)
+                backport_sha = backport_response.json().get("merge_commit_sha")
+                if backport_sha is None:
+                    results[f"nixos-24.05 (#{backport_pr})"] = False
+                    return PRStatus(merged=True, branches=results)
+
+                results.pop("nixos-24.05")
+                results[f"nixos-24.05 (#{backport_pr})"] = commit_in_branch(
+                    backport_sha, "nixos-24.05"
+                )
+
     return PRStatus(merged=True, branches=results)