Add affects_rhel() check

tests/test_errata.py

@@ -4,6 +4,7 @@
 from langchain_core.documents import Document
 
 from textprep.errata import (
+    affects_rhel,
     clean_bugzillas,
     clean_description,
     clean_solution,
@@ -170,3 +171,30 @@ def test_parse_functional(errata_doc_path):
 
 - BZ 2044863 found at https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=2044863"""
     assert result == expected
+
+
+def test_affects_rhel(tmp_path):
+    content = """+++
+portal_product_names=["Red Hat Enterprise Linux Server - Extended Life Cycle Support","Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions","Red Hat Enterprise Linux for x86_64 - Extended Update Support","Red Hat Enterprise Linux Desktop","Red Hat Enterprise Linux Server - AUS","Red Hat Enterprise Linux EUS Compute Node","Red Hat Enterprise Linux Server - TUS","Red Hat Enterprise Linux Server","Red Hat Enterprise Linux Workstation","Red Hat Enterprise Linux Server from RHUI","Red Hat Enterprise Linux for Scientific Computing"]
++++
+
+# Heading
+
+Content.
+"""
+    d = tmp_path / "sub"
+    d.mkdir()
+    p = d / "errata.md"
+    p.write_text(content, encoding="utf-8")
+    assert affects_rhel(p)
+
+    content = """+++
+portal_product_names=["Red Hat OpenShift Enterprise Infrastructure","Red Hat OpenShift Enterprise Application Node","Red Hat OpenShift Enterprise JBoss EAP add-on","Red Hat OpenShift Enterprise Client Tools"]
++++
+
+# Heading
+
+Content.
+"""
+    p.write_text(content, encoding="utf-8")
+    assert not affects_rhel(p)

textprep/errata.py

@@ -103,6 +103,13 @@ def get_affected_products(product_keys: list, product_detail: list) -> str:
     return "This errata affects the following products:\n\n" + product_text
 
 
+def affects_rhel(path: str) -> bool:
+    """Check if the errata affects RHEL."""
+    errata_doc = load_errata(path)
+    affected_products = errata_doc["frontmatter"]["portal_product_names"]
+    return any("Red Hat Enterprise Linux" in x for x in affected_products)
+
+
 def parse(path: str) -> str:
     """Parse an errata document into a clean format."""
     errata_doc = load_errata(path)