qapi/source: Remove line number from QAPISourceInfo initializer

With the QAPISourceInfo(None, None, None) construct gone, there's no
longer any reason to have to specify that a file starts on the first
line. Remove it from the initializer and default it to 1.

Remove the last vestiges where we check for 'line' being unset, that
can't happen, now.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-4-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

scripts/qapi/parser.py

@@ -47,7 +47,7 @@ def __init__(self, fname, previously_included=None, incl_info=None):
         if self.src == '' or self.src[-1] != '\n':
             self.src += '\n'
         self.cursor = 0
-        self.info = QAPISourceInfo(fname, 1, incl_info)
+        self.info = QAPISourceInfo(fname, incl_info)
         self.line_pos = 0
         self.exprs = []
         self.docs = []

scripts/qapi/source.py

@@ -31,10 +31,9 @@ def __init__(self) -> None:
 class QAPISourceInfo:
     T = TypeVar('T', bound='QAPISourceInfo')
 
-    def __init__(self, fname: str, line: int,
-                 parent: Optional['QAPISourceInfo']):
+    def __init__(self, fname: str, parent: Optional['QAPISourceInfo']):
         self.fname = fname
-        self.line = line
+        self.line = 1
         self.parent = parent
         self.pragma: QAPISchemaPragma = (
             parent.pragma if parent else QAPISchemaPragma()
@@ -52,10 +51,7 @@ def next_line(self: T) -> T:
         return info
 
     def loc(self) -> str:
-        ret = self.fname
-        if self.line is not None:
-            ret += ':%d' % self.line
-        return ret
+        return f"{self.fname}:{self.line}"
 
     def in_defn(self) -> str:
         if self.defn_name: