fix: add more information to the debug output

The previous debug output did not help to understand which file where fixed in
which revision. The new output should cover that.

hgext/fix.py

@@ -698,6 +698,9 b' def fixfile(ui, repo, opts, fixers, fixc'
             command = fixer.command(ui, path, ranges)
             if command is None:
                 continue
+            msg = b'fixing: %s - %s - %s\n'
+            msg %= (fixctx, fixername, path)
+            ui.debug(msg)
             ui.debug(b'subprocess: %s\n' % (command,))
             proc = subprocess.Popen(
                 procutil.tonativestr(command),

tests/test-fix.t

@@ -1153,6 +1153,7 b' useful for anyone trying to set up a new'
   $ hg commit -Aqm "foo"
   $ printf "Foo\nbar\nBaz\n" > foo.changed
   $ hg --debug fix --working-dir
+  fixing: f65cf3136d41+ - uppercase-changed-lines - foo.changed
   subprocess: * $TESTTMP/uppercase.py 1-1 3-3 (glob)
 
   $ cd ..