adapt cnfvar stdout writer for python3

stdio output still trips over the bytes / string separation. Fix
it by defaulting to bytes which mirrors the reader. Add optional
string writer for use with direct text output.

diff --git a/src/cnfvar.py b/src/cnfvar.py
index b31f6f3..04e97b2 100644 (file)
--- a/src/cnfvar.py
+++ b/src/cnfvar.py
@@ -513,14 +513,14 @@ def renumber_vars(root, parent=None):
 #                                serialization
 #
 
-cnf_line_nest_indent = "  "
-cnf_line_base_fmt = "%d %s,%d: \"%s\""
-cnf_line_child_fmt = "%d %s(%d) %s,%d: \"%s\""
+cnf_line_nest_indent = b"  "
+cnf_line_base_fmt    = b"%d %s,%d: \"%s\""
+cnf_line_child_fmt   = b"%d %s(%d) %s,%d: \"%s\""
 
 
 def format_cnf_vars(da, var):
     """
-    Return a list of formatted cnf_line strings.
+    Return a list of formatted cnf_line byte strings.
     """
 
     depth, acc = da
@@ -530,19 +530,19 @@ def format_cnf_vars(da, var):
             % (var["number"],
                cnf_line_nest_indent * depth,
                var["parent"],
-               to_latin1(var["varname"]).decode (),
+               to_latin1(var["varname"]),
                var["instance"],
-               to_latin1(var["data"]).decode ())
+               to_latin1(var["data"]))
     else:
         line = cnf_line_base_fmt \
             % (var["number"],
-               to_latin1(var["varname"]).decode (),
+               to_latin1(var["varname"]),
                var["instance"],
-               to_latin1(var["data"]).decode ())
+               to_latin1(var["data"]))
 
     comment = var.get("comment", None)
-    if comment and comment is not "":
-        line = line + (" # %s" % to_latin1(comment))
+    if comment and len (comment) != 0:
+        line = line + (b" # %s" % to_latin1(comment))
 
     acc.append(line)
 
@@ -571,7 +571,7 @@ def write_cnf_raw(*argv, **kw_argv):
     print_cnf_raw(*argv, **kw_argv)
 
 
-def output_cnf(root, out, renumber=False):
+def output_cnf(root, out, renumber=False, bytes=True):
     cnf = cnf_root(root)
     # Cthulhu (a.k.a Autotest) hates us so much he replaced the innocuous
     # stdout with some chimera that isn't derived from ``file``, rendering
@@ -582,8 +582,25 @@ def output_cnf(root, out, renumber=False):
         _count = renumber(root)
     if is_cnf(cnf) is True:
         (_, lines) = functools.reduce(format_cnf_vars, cnf, (0, []))
-        out.write("\n".join(lines))
-        out.write("\n")
+        if bytes is True:
+            out.write ("\n".join (map (from_latin1, lines)))
+            out.write ("\n")
+        else:
+            out.write (b"\n".join (lines))
+            out.write (b"\n")
+
+
+def dump_cnf_bytes (root, renumber=False):
+    """
+    dump_cnf_bytes -- Serialize CNF var structure, returning the result as a
+    byte sequence.
+    """
+    cnf = cnf_root(root)
+    out = io.BytesIO()
+    output_cnf(root, out, renumber=renumber, bytes=True)
+    res = out.getvalue()
+    out.close()
+    return res
 
 
 def dump_cnf_string(root, renumber=False):
@@ -593,12 +610,11 @@ def dump_cnf_string(root, renumber=False):
     """
     cnf = cnf_root(root)
     out = io.StringIO()
-    output_cnf(root, out, renumber=renumber)
+    output_cnf(root, out, renumber=renumber, bytes=False)
     res = out.getvalue()
     out.close()
     return res
 
-
 def print_cnf(root, out=None, renumber=False):
     if root is not None:
         output_cnf(root, out or sys.stdout, renumber=renumber)