[glib] mkenums: Change ordering for template file and arguments

[Emmanuele Bassi <ebassi src gnome org>]

commit 77a3a962189df86a48c28a3c35d46575f35f7b95
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Mon Jul 17 09:36:13 2017 +0100

    mkenums: Change ordering for template file and arguments
    
    This is a bit of a hack to maintain some semblance of backward
    compatibility with the old, Perl-based glib-mkenums. The old tool had an
    implicit ordering on the arguments and templates; each argument was
    parsed in order, and all the strings appended. This allowed developers
    to write:
    
      glib-mkenums \
        --fhead ... \
        --template a-template-file.c.in \
        --ftail ...
    
    And have the fhead be prepended to the file-head stanza in the template,
    as well as the ftail be appended to the file-tail stanza in the
    template.  Short of throwing away ArgumentParser and going over
    sys.argv[] element by element, we can simulate that behaviour by
    ensuring some ordering in how we build the template strings:
    
      - the head stanzas are always prepended to the template
      - the prod stanzas are always appended to the template
      - the tail stanzas are always appended to the template
    
    Within each instance of the command line argument, we append each value
    to the array in the order in which it appears on the command line.
    
    This change fixes the libqmi build.

 gobject/glib-mkenums.in |   41 ++++++++++++++++++++++++++++++++++-------
 1 files changed, 34 insertions(+), 7 deletions(-)
---
diff --git a/gobject/glib-mkenums.in b/gobject/glib-mkenums.in
index 1b03142..cff0da3 100755
--- a/gobject/glib-mkenums.in
+++ b/gobject/glib-mkenums.in
@@ -265,24 +265,51 @@ options = parser.parse_args()
 if options.version:
     print_version()
 
-if options.template != '':
-    read_template_file(options.template)
-
 def unescape_cmdline_args(arg):
     arg = arg.replace('\\n', '\n')
     arg = arg.replace('\\r', '\r')
     return arg.replace('\\t', '\t')
 
+if options.template != '':
+    read_template_file(options.template)
+
 idprefix += options.idprefix
 symprefix += options.symprefix
-fhead += ''.join([unescape_cmdline_args(x) for x in options.fhead])
-ftail += ''.join([unescape_cmdline_args(x) for x in options.ftail])
+
+# This is a hack to maintain some semblance of backward compatibility with
+# the old, Perl-based glib-mkenums. The old tool had an implicit ordering
+# on the arguments and templates; each argument was parsed in order, and
+# all the strings appended. This allowed developers to write:
+#
+#   glib-mkenums \
+#     --fhead ... \
+#     --template a-template-file.c.in \
+#     --ftail ...
+#
+# And have the fhead be prepended to the file-head stanza in the template,
+# as well as the ftail be appended to the file-tail stanza in the template.
+# Short of throwing away ArgumentParser and going over sys.argv[] element
+# by element, we can simulate that behaviour by ensuring some ordering in
+# how we build the template strings:
+#
+#   - the head stanzas are always prepended to the template
+#   - the prod stanzas are always appended to the template
+#   - the tail stanzas are always appended to the template
+#
+# Within each instance of the command line argument, we append each value
+# to the array in the order in which it appears on the command line.
+fhead = ''.join([unescape_cmdline_args(x) for x in options.fhead]) + fhead
+vhead = ''.join([unescape_cmdline_args(x) for x in options.vhead]) + vhead
+
 eprod += ''.join([unescape_cmdline_args(x) for x in options.eprod])
-vhead += ''.join([unescape_cmdline_args(x) for x in options.vhead])
 vprod += ''.join([unescape_cmdline_args(x) for x in options.vprod])
-vtail += ''.join([unescape_cmdline_args(x) for x in options.vtail])
+
+ftail = ftail + ''.join([unescape_cmdline_args(x) for x in options.ftail])
+vtail = vtail + ''.join([unescape_cmdline_args(x) for x in options.vtail])
+
 if options.comment_tmpl != '':
     comment_tmpl = unescape_cmdline_args(options.comment_tmpl)
+
 output = options.output
 
 if output is not None: