[PATCH 16/22] qapi/parser: add docstrings

[John Snow <jsnow@redhat.com>]

Signed-off-by: John Snow <jsnow@redhat.com>

---

My hubris is infinite.

OK, I only added a few -- to help me remember how the parser works at a glance.

Signed-off-by: John Snow <jsnow@redhat.com>
---
 scripts/qapi/parser.py | 66 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)

diff --git a/scripts/qapi/parser.py b/scripts/qapi/parser.py
index dbbd0fcbc2f..8fc77808ace 100644
--- a/scripts/qapi/parser.py
+++ b/scripts/qapi/parser.py
@@ -51,7 +51,24 @@ def __init__(self, parser: 'QAPISchemaParser', msg: str):
 
 
 class QAPISchemaParser:
+    """
+    Performs parsing of a QAPI schema source file.
 
+    :param fname: Path to the source file.
+    :param previously_included:
+        The absolute paths of previously included source files.
+        Only used by recursive calls to avoid re-parsing files.
+    :param incl_info:
+       `QAPISourceInfo` for the parent document.
+       This may be None if this is the root schema document.
+
+    :ivar exprs: Resulting parsed expressions.
+    :ivar docs: Resulting parsed documentation blocks.
+
+    :raise OSError: For problems opening the root schema document.
+    :raise QAPIParseError: For JSON or QAPIDoc syntax problems.
+    :raise QAPISemError: For various semantic issues with the schema.
+    """
     def __init__(self,
                  fname: str,
                  previously_included: Optional[Set[str]] = None,
@@ -77,6 +94,11 @@ def __init__(self,
         self._parse()
 
     def _parse(self) -> None:
+        """
+        Parse the QAPI schema document.
+
+        :return: None; results are stored in ``exprs`` and ``docs``.
+        """
         cur_doc = None
 
         with open(self._fname, 'r', encoding='utf-8') as fp:
@@ -197,6 +219,50 @@ def _check(name: str, value: object) -> List[str]:
             raise QAPISemError(info, "unknown pragma '%s'" % name)
 
     def accept(self, skip_comment: bool = True) -> None:
+        """
+        Read the next lexeme and process it into a token.
+
+        :Object state:
+          :tok: represents the token type. See below for values.
+          :pos: is the position of the first character in the lexeme.
+          :cursor: is the position of the next character.
+          :val: is the variable value of the token, if any.
+
+        Single-character tokens:
+
+        These include ``LBRACE``, ``RBRACE``, ``COLON``, ``COMMA``,
+        ``LSQB``, and ``RSQB``.  ``tok`` holds the single character
+        lexeme.  ``val`` is ``None``.
+
+        Multi-character tokens:
+
+        - ``COMMENT``:
+
+          - This token is not normally yielded by the lexer, but it
+            can be when ``skip_comment`` is False.
+          - ``tok`` is the value ``"#"``.
+          - ``val`` is a string including all chars until end-of-line.
+
+        - ``STRING``:
+
+          - ``tok`` is the ``"'"``, the single quote.
+          - ``value`` is the string, *excluding* the quotes.
+
+        - ``TRUE`` and ``FALSE``:
+
+          - ``tok`` is either ``"t"`` or ``"f"`` accordingly.
+          - ``val`` is either ``True`` or ``False`` accordingly.
+
+        - ``NEWLINE`` and ``SPACE``:
+
+          - These are consumed by the lexer directly. ``line_pos`` and
+            ``info`` are advanced when ``NEWLINE`` is encountered.
+            ``tok`` is set to ``None`` upon reaching EOF.
+
+        :param skip_comment:
+            When false, return ``COMMENT`` tokens.
+            This is used when reading documentation blocks.
+        """
         while True:
             self.tok = self.src[self.cursor]
             self.pos = self.cursor
-- 
2.30.2