fix(ci): use gh api --slurp to parse paginated issues in close_duplicate_issues.py

The Check Duplicate Issues workflow crashed on every issues event with
json.decoder.JSONDecodeError. fetch_open_issues split gh api --paginate
output with splitlines() and parsed each line as JSON, but gh concatenates
pages without guaranteeing each physical line is a self-contained JSON
document, and splitlines() also breaks on unescaped Unicode line
separators (U+2028/U+2029) that GitHub returns raw inside issue bodies.
Fetch with --slurp instead, which emits one well-formed JSON array of
pages, and flatten it.

Fixes #32217

.github/scripts/close_duplicate_issues.py

@@ -40,27 +40,17 @@ def gh(*args: str) -> str:
 
 
 def fetch_open_issues(repo: str | None) -> list[dict]:
-    """Fetch all open issues (excluding PRs) via gh api --paginate."""
+    """Fetch all open issues (excluding PRs) via gh api --paginate --slurp."""
     if repo:
         endpoint = (
             f"repos/{repo}/issues?state=open&per_page=100&sort=created&direction=asc"
         )
     else:
         endpoint = "repos/{owner}/{repo}/issues?state=open&per_page=100&sort=created&direction=asc"
-    cmd = ["api", "--paginate", endpoint]
 
-    raw = gh(*cmd)
-    # gh --paginate concatenates JSON arrays, so we may get multiple arrays
-    issues = []
-    for line in raw.strip().splitlines():
-        line = line.strip()
-        if not line:
-            continue
-        parsed = json.loads(line)
-        if isinstance(parsed, list):
-            issues.extend(parsed)
-        else:
-            issues.append(parsed)
+    raw = gh("api", "--paginate", "--slurp", endpoint)
+    pages = json.loads(raw)
+    issues = [issue for page in pages for issue in page]
 
     # Filter out pull requests (they also appear in the issues endpoint)
     return [i for i in issues if "pull_request" not in i]

tests/test_litellm/test_github_close_duplicate_issues.py

@@ -0,0 +1,75 @@
+from __future__ import annotations
+
+import importlib.util
+import json
+import sys
+from pathlib import Path
+
+import pytest
+
+SCRIPT_PATH = Path(__file__).resolve().parents[2] / ".github" / "scripts" / "close_duplicate_issues.py"
+
+
+@pytest.fixture(scope="module")
+def closer_module():
+    spec = importlib.util.spec_from_file_location("close_duplicate_issues", SCRIPT_PATH)
+    assert spec and spec.loader, f"Could not load spec for {SCRIPT_PATH}"
+    module = importlib.util.module_from_spec(spec)
+    sys.modules["close_duplicate_issues"] = module
+    spec.loader.exec_module(module)
+    return module
+
+
+def _issue(number: int, title: str, body: str = "") -> dict:
+    return {"number": number, "title": title, "body": body}
+
+
+def _fake_gh_cli(pages: list[list[dict]]):
+    def fake_gh(*args: str) -> str:
+        assert args[0] == "api"
+        assert "--paginate" in args
+        if "--slurp" in args:
+            return json.dumps(pages, ensure_ascii=False)
+        return "".join(json.dumps(page, ensure_ascii=False) for page in pages)
+
+    return fake_gh
+
+
+class TestFetchOpenIssues:
+    def test_should_parse_multi_page_payload_with_unescaped_line_separators(self, closer_module, monkeypatch):
+        pages = [
+            [_issue(1, "first bug", body="traceback\u2028line two\u2028line three")],
+            [_issue(2, "second bug"), _issue(3, "third bug")],
+        ]
+        monkeypatch.setattr(closer_module, "gh", _fake_gh_cli(pages))
+
+        issues = closer_module.fetch_open_issues("BerriAI/litellm")
+
+        assert [i["number"] for i in issues] == [1, 2, 3]
+
+    def test_should_request_slurp_mode(self, closer_module, monkeypatch):
+        calls: list[tuple[str, ...]] = []
+
+        def recording_gh(*args: str) -> str:
+            calls.append(args)
+            return json.dumps([[]])
+
+        monkeypatch.setattr(closer_module, "gh", recording_gh)
+
+        closer_module.fetch_open_issues("BerriAI/litellm")
+
+        assert len(calls) == 1
+        assert "--slurp" in calls[0]
+
+    def test_should_filter_out_pull_requests(self, closer_module, monkeypatch):
+        pages = [
+            [
+                _issue(1, "real issue"),
+                {**_issue(2, "a pr"), "pull_request": {"url": "https://x"}},
+            ]
+        ]
+        monkeypatch.setattr(closer_module, "gh", _fake_gh_cli(pages))
+
+        issues = closer_module.fetch_open_issues("BerriAI/litellm")
+
+        assert [i["number"] for i in issues] == [1]