Julius Hacker Reporter
	Description • 19 years ago

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.8) Gecko/20050511 Firefox/1.0.4
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.8) Gecko/20050511 Firefox/1.0.4

It would be nice to be able to use variable tabulator widths instead of the
fixed width of 4 spaces. Personally I work with a tabulator width of 2 spaces in
my editor and when I view the code of a website with firefox it's very
irritating to have a tabulator width of 4 spaces.

Reproducible: Always

	Nickolay_Ponomarev
	Comment 1 • 19 years ago

confirming as a valid enhancement request, but I don't think this will be
implemented, as Firefox's view source is intended to be a very simple source viewer.

	Ryan Lowe
	Comment 3 • 17 years ago

As I mentioned in bug #390935 (duplicate of this bug now) I consistently see a tab width of 8 characters, not 4 (my preference is 2).  A tab width of 8 characters can move some deeply indented lines halfway across the view source window.

A preference in about:config to set the view source tab width would be great!

	Geoff Lankow (:darktrojan) Assignee
	Comment 4 • 15 years ago

A small amount of investigation reveals:

* 8 space widths is hard-coded into ComputeTabWidthAppUnits in layout/generic/nsTextFrameThebes.cpp
* This is because the CSS specifies tabs preformatted text must be equal to 8 spaces in width

Can't see either of these changing soon, short-sighted as they seem.

	Gary Turner
	Comment 5 • 15 years ago

Thanks, Geoff, for the explanation of where the problem lives.

I, too, have long despised the eight space tab.  Surely the rules of css do not apply to an application displaying source material.  I can see that the source viewer might default to an existing stylesheet, but would it be all that difficult to create a viewer-only stylesheet, and have the viewer link to it?

I apologize if I'm talking through my hat; my C coding experience is so close to zero as to be indistinguishable.

	Geoff Lankow (:darktrojan) Assignee
	Comment 6 • 15 years ago

This is probably going to break a million tests, cause a performance hit, and generally annoy a few things. Especially as it defies the CSS specification.

But it does work.

	Geoff Lankow (:darktrojan) Assignee
	Comment 7 • 15 years ago

Gary: The major problem is that the view-source page is actually an HTML page, and is displayed using all the same code as a normal page.

Robert, I don't know if you're the right person to talk to about this, but I have some questions (mostly because I'm delving into code I don't know and don't really understand):

Is getting this pref here a bad idea? How often is ComputeTabWidthAppUnits called? Should I cache the answer somewhere?

What tests is this going to break? The only tests I've worked with before are XPCShell tests and I don't think they're really going to help here.

	Robert O'Callahan (:roc) (email my personal email if necessary)
	Comment 8 • 15 years ago

The best approach here would be to implement -moz-tab-size similar to Opera's -o-tab-size. See
http://lists.w3.org/Archives/Public/www-style/2008Dec/0009.html

It would be pretty easy to do. You'd add it to nsStyleText.

	Geoff Lankow (:darktrojan) Assignee
	Comment 9 • 15 years ago

This patch sets -moz-tab-size using the style attribute on the BODY node in a view-source page.

I'm considering adding UI to the view source window, but for now it just works off a pref.

	Geoff Lankow (:darktrojan) Assignee
	Comment 10 • 15 years ago

Patch including front-end for view source window

	flying sheep
	Comment 12 • 15 years ago

a setting for the standard tab-size would be also great. (maybe in the window where you can set your standard sans, serif and monospace font):
a small field where you can enter a digit from 2 to 9 (everything else is useless)

	flying sheep
	Comment 13 • 15 years ago

oh, sorry: i want the setting to be used for the whole firefox. (e.g. viewing source code on web pages)
maybe my bug is no duplicate, then?

is the -moz-tab-size attribute also available for normal use? (so you can just use “* {-moz-tab-size:4}” in the userstyle.css or as a stylish-style)

	:Gavin Sharp [email: gavin@gavinsharp.com]
	Comment 15 • 15 years ago

Comment on attachment 402269 [details] [diff] [review]
patch v2

I think UI for this is probably overkill. Let's just add the viewsource backend changes so that people who want this can just change the pref manually?

I think mrbkap is the best person to review those changes.

	Blake Kaplan (:mrbkap) (inactive)
	Comment 17 • 14 years ago

Comment on attachment 424330 [details] [diff] [review]
patch v3

>@@ -397,16 +402,23 @@ NS_IMETHODIMP CViewSourceHTML::BuildMode
>                         NS_LITERAL_STRING("id"),
>                         NS_ConvertASCIItoUTF16(kBodyId));
> 
>           if (mWrapLongLines) {
>             AddAttrToNode(bodyNode, theAllocator,
>                           NS_LITERAL_STRING("class"),
>                           NS_ConvertASCIItoUTF16(kBodyClassWrap));
>           }
>+          if (mTabSize >= 0) {
>+            nsAutoString styleValue = NS_ConvertASCIItoUTF16(kBodyTabSize);
>+            styleValue.AppendInt (mTabSize);

Nit: No space before (.

>diff --git a/parser/htmlparser/src/nsViewSourceHTML.h b/parser/htmlparser/src/nsViewSourceHTML.h
>     PRPackedBool        mSyntaxHighlight;
>     PRPackedBool        mWrapLongLines;
>+    PRInt32             mTabSize;
>     PRPackedBool        mHasOpenRoot;
>     PRPackedBool        mHasOpenBody;

Please move mTabSize out of the PRPackedBools so that they pack correctly (before mSyntaxHighlight should work).

Looks good otherwise.

	Geoff Lankow (:darktrojan) Assignee
	Comment 18 • 14 years ago

Right, let's get this fixed at long last!

	Dão Gottwald [:dao]
	Comment 19 • 14 years ago

http://hg.mozilla.org/mozilla-central/rev/a7e6a9d1b8ea

	Geoff Lankow (:darktrojan) Assignee
	Comment 20 • 14 years ago

For userdocs: the preference "view_source.tab_size" sets the width of a tab character in the view source window. Already open windows aren't updated.

	Chris Ilias [:cilias]
	Comment 21 • 14 years ago

Removing user-doc-needed.
We don't document anything that encourages the user to go to about:config, unless it is for troubleshooting or it is a frequently asked question.

	Nickolay_Ponomarev
	Comment 22 • 14 years ago

Historically, all preferences are documented on kb.mozillazine.org: I added a mention of the new pref to http://kb.mozillazine.org/About:config_entries#View_source.

	Geoff Lankow (:darktrojan) Assignee
	Comment 23 • 14 years ago

(In reply to comment #21)
> Removing user-doc-needed.
> We don't document anything that encourages the user to go to about:config,
> unless it is for troubleshooting or it is a frequently asked question.

(In reply to comment #22)
> Historically, all preferences are documented on kb.mozillazine.org: I added a
> mention of the new pref to
> http://kb.mozillazine.org/About:config_entries#View_source.

Okay, that's the outcome I wanted anyway.