The variable $RenamedSourceFileName should be provided to show file names with replacements being applied

Current Situation

• The parameters source_replacing=... and source_replacement=... are set.
• The variable $SourceFileName is available for the source commands (source_pre_command=..., source_tfn_post_command=..., source_post_command=...) which shows the original file names, i.e. no replacement has been applied.
• A variable which shows the renamed file name doesn't exist.

Desired Behavior

• The variable $SourceFileName shows the "original" file name.
• The variable $RenamedSourceFileName shows the file name including the replacements.