TortoiseSVN has the amazing ability to diff Microsoft Word document revisions, made possible apparently by a script in C:\Program Files\TortoiseSVN\Diff-Scripts which calls out to MS Word to do the diff (instead of using TortoiseMerge to diff them as text files, which of course wouldn't work for Word files). MS Word itself is able to diff two versions of .dot or .dotx files, using the same user interface "clicks" as diffing two versions of .doc or .docx files, so it would seem that the TortoiseSVN script for .doc and .docx files (diff-doc.js) should also work for .dot and .dotx files.
In attempting to enable TortoiseSVN to diff .dot and .dotx files, I edited the first line of diff-doc.js from this...
// extensions: doc;docx;docm ...to this:
// extensions: doc;docx;docm;dot;dotx And then I tried using TortoiseSVN to diff a .dot file with its previous version, and it behaved the same as before (TortoiseMerge complained that it wasn't a valid text file). Thinking perhaps TortoiseSVN only checks the extensions comments in the script files once on startup, I rebooted, and still the same behavior.
Am I missing something necessary to make TortoiseSVN diff .dot & .dotx files? (BTW, I am aware that the .dot extension is used by other programs for things unrelated to MS Word, and I am aware that this makes files with .dot extensions ambiguous with regard to their true file format.)