Fossil

For example, you could click two of those checkboxes and then a button
labeled “Diff Selected” to replicate the current “click two nodes to
diff them” feature.

[wt]: https://fossil-scm.org/fossil/timeline


### <a id="wedit"></a>WYSIWYG Wiki Editor
### <a id="wedit"></a>The New Wiki Editor

As of Fossil 2.12, the [Fossil wiki][fwt] document editor requires
JavaScript, for a few unavoidable reasons.
The Admin → Wiki → “Enable WYSIWYG Wiki Editing” toggle switches the
default plaintext editor for [Fossil wiki][fw] documents to one that
works like a basic word processor. This feature requires JavaScript in
order to react to editor button clicks like the “**B**” button, meaning
“make \[selected\] text boldface.” There is no standard WYSIWYG editor
component in browsers, doubtless because it’s relatively straightforward
to create one using JavaScript.

First, it allows in-browser previews without losing client-side editor
state, such as where your cursor is. With the old editor, you had to
re-locate the place you were last editing on each preview, which would
reduce the incentive to use the preview function. In the new wiki
editor, you just click the Preview tab to see how Fossil interprets your
markup, then click back to the Editor tab to resume work with the prior
context undisturbed.

Second, it continually saves your document state in client-side storage
in the background while you’re editing it so that if the browser closes
without saving the changes back to the Fossil repository, you can resume
editing from the stored copy without losing work. This feature is not so
much about saving you from crashes of various sorts, since computers are
so much more reliable these days. It is far more likely to save you from
the features of mobile OSes like Android and iOS which aggressively shut
down and restart apps to save on RAM. That OS design philosophy assumes
that there is a way for the app to restore its prior state from
persistent media when it’s restarted, giving the illusion that it was
never shut down in the first place. This feature of Fossil’s new wiki
editor provides that.

There are many other new features in the enhanced Fossil 2.12 wiki
editor, but those are the ones that absolutely require JavaScript to
work.

With this change, we lost the old WYSIWYG wiki editor, available since
Fossil version 1.24. It hadn’t been maintained for years, it was
disabled by default, and no one stepped up to defend its existence when
this new editor was created, replacing it. If someone rescues that
feature, merging it in with the new editor, it will doubtless require
JavaScript in order to react to editor button clicks like the “**B**”
button, meaning “make \[selected\] text boldface.” There is no standard
WYSIWYG editor component in browsers, doubtless because it’s relatively
straightforward to create one using JavaScript.

_Graceful Fallback:_ Unlike in the Fossil 2.11 and earlier days, there
is no longer a script-free wiki editor mode. This is not from lack of
desire, only because the person who wrote the new wiki editor didn’t
want to maintain three different editors. (New Ajaxy editor, old
script-free HTML form based editor, and old WYSIWYG JS-based editor.) If
someone wants to implement a `<noscript>` alternative to the new wiki
editor, we will likely accept that [contribution][cg] as long as it
doensn’t interfere with the new editor. (The same goes for adding a
WYSIWYG mode to the new Ajaxy wiki editor.)
_Graceful Fallback:_ Edit your wiki documents in the default plain text
wiki editor. Fossil’s wiki and Markdown language processors were
designed to be edited that way.

_Workaround:_ You don’t have to use the browser-based wiki editor to
maintain your repository’s wiki at all. Fossil’s [`wiki` command][fwc]
lets you manipulate wiki documents from the command line. For example,
consider this `vi` based workflow:

```shell
    $ vi 'My Article.wiki'                   # write, write, write...
    :!fossil create 'My Article' '%'         # current file (%) to new article
      ...write, write, write some more...
    :w                                       # save changes to disk copy
    :!fossil commit 'My Article' '%'         # update article from disk
    :q                                       # done writing for today

      ....days later...
    $ vi                                     # work sans named file today
    :r !fossil wiki export 'My Article' -    # article text into vi buffer
      ...write, write, write yet more...
    :w !fossil wiki commit -                 # update article with buffer
```

Extending this concept to other text editors is an exercise left to the
reader.

[fwc]: /help?cmd=wiki
[fw]: ./wikitheory.wiki
[fwt]: ./wikitheory.wiki


### <a id="ln"></a>Line Numbering

When viewing source files, Fossil offers to show line numbers in some
cases. Toggling them on and off is currently handled in JavaScript.
([Example][mainc].)