Issue 3675: Make convert-ly -d only ever update on changed files

Previously, it updated unconditionally whenever a new stable version
came out, leading to merge conflicts.  When the final applied
conversion is to an unstable version and the following stable version
is not beyond the conversion target, the following stable version is
used.

Note that this rule does not make a factual difference for continuous
updates of a code base (the normal use case for
scripts/auxiliar/update-with-convert-ly.sh), but it makes a difference
for the conversion/import of code that may have fallen behind a lot
(like with the LSR import, or when converting archived files).

diff --git a/Documentation/usage/updating.itely b/Documentation/usage/updating.itely
index 06a960ac8a866faff27da9fece4208a96d395a78..ad92a834e35db8307521379f9dc4bd9789e6ce09 100644 (file)
--- a/Documentation/usage/updating.itely
+++ b/Documentation/usage/updating.itely
@@ -151,8 +151,11 @@ The following options can be given:
 @item -d, --diff-version-update
 increase the @code{\version} string only if the file has actually
 been changed.  In that case, the version header will correspond to
-the version after the last actual change.  Without that option,
-the version will reflect the last @emph{attempted} conversion.
+the version after the last actual change.  An unstable version
+number will be rounded up to the next stable version number unless
+that would exceed the target version number.  Without this option,
+the version will instead reflect the last @emph{attempted}
+conversion.
 
 @item -e, --edit
 Apply the conversions direct to the input file, modifying it

diff --git a/scripts/convert-ly.py b/scripts/convert-ly.py
index 641d763713c979c06dfe0621e19959303765403d..ede9d4a98b81ea7309288364603c2a767cdca00a 100644 (file)
--- a/scripts/convert-ly.py
+++ b/scripts/convert-ly.py
@@ -292,17 +292,18 @@ def do_one_file (infile_name):
             # Note that last_change can be set even if the result is
             # the same if two conversion rules cancelled out
             if result == input:
-                # check the y in x.y.z  (minor version number)
-                previous_stable = (last[0], 2*(last[1]/2), 0)
-                if ((last[0:2] != from_version[0:2]) and
-                    (previous_stable > from_version)):
-                    # previous stable version
-                    last = previous_stable
-                else:
-                    # make no (actual) change to the version number
-                    last = from_version
+                # make no (actual) change to the version number
+                last = from_version
             else:
                 last = last_change
+                # If the last update was to an unstable version
+                # number, and the final update target is no longer in
+                # the same unstable series, we update to the stable
+                # series following the unstable version.
+                if last[1]%2: # unstable
+                    next_stable = (last[0], last[1]+1, 0)
+                    if next_stable <= to_version:
+                        last = next_stable
 
         newversion = r'\version "%s"' % tup_to_str (last)
         if lilypond_version_re.search (result):