qapi/parser: don't parse rST markup as section headers

The double-colon synax is rST formatting that precedes a literal code
block. We do not want to capture these as QAPI-specific sections.

Coerce blocks that start with e.g. "Example::" to be parsed as untagged
paragraphs instead of special tagged sections.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-ID: <20240626222128.406106-14-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Indentation tweaked for consistency]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

scripts/qapi/parser.py

@@ -544,10 +544,15 @@ class QAPISchemaParser:
                         line = self.get_doc_indented(doc)
                     no_more_args = True
                 elif match := re.match(
-                        r'(Returns|Errors|Since|Notes?|Examples?|TODO): *',
-                        line):
+                        r'(Returns|Errors|Since|Notes?|Examples?|TODO)'
+                        r'(?!::): *',
+                        line,
+                ):
                     # tagged section
 
+                    # Note: "sections" with two colons are left alone as
+                    # rST markup and not interpreted as a section heading.
+
                     # TODO: Remove this error sometime in 2025 or so
                     # after we've fully transitioned to the new qapidoc
                     # generator.

tests/qapi-schema/doc-good.json

@@ -181,6 +181,9 @@
 #  - *verbatim*
 #  - {braces}
 #
+# Note::
+#     Ceci n'est pas une note
+#
 # Since: 2.10
 ##
 { 'command': 'cmd',

tests/qapi-schema/doc-good.out

@@ -190,6 +190,9 @@ frobnicate
     section=Examples
  - *verbatim*
  - {braces}
+    section=None
+Note::
+    Ceci n'est pas une note
     section=Since
 2.10
 doc symbol=cmd-boxed

tests/qapi-schema/doc-good.txt

@@ -231,6 +231,9 @@ Examples
    - *verbatim*
    - {braces}
 
+Note::
+   Ceci n'est pas une note
+
 
 Since
 ~~~~~