This is the well known file locking problem: The TempFile class keeps the
created file locked for the own process, and this prevents the CAS to read it.
Instead of resetting it to false, do a proper test to see whether
there is a separator at the end of the row.
Fixes bug #10180.
(cherry picked from commit 5e5440f2f3)
The computation of the index of the main text entry of a row did not take into
account the fact that the entry could be optimised away.
(cherry picked from commit 947c34364c)
output of tags until we know they're needed. In the case of HTML
tables, empty cells should of course be output, so we need to force
the tags to be output.
(cherry picked from commit 35d449c5da)
TocModels::reset() in GuiView::structureChanged() collapses the TocWidget, and
therefore requires an update right after, which was missing.
In fact, profiling TocWidget::updateView() shows that delaying the update is
good only for fast keypresses (essentially movement). It costs 5% of a
char-forward operation in a document with approx. 100 table of contents
items. The update optimisation has been rewritten to take this data into
account.
This also fixes#9826: Outline disclosure of subsection content disappears one
second after doubleclicking content item.
In some cases, the insets may change height or width without changing
the other apsects of the row.
Fixes bug #6991 and #10182.
(cherry picked from commit 508518ad95)
The computation of the width of the button was wrong. If <--> stands
for TEXT_TO_INSET_OFFSET/2 spacing, and if `[]' marks the button's
limits, then the intent is
<-->[<-->button text<-->]<-->
Therefore the physical grey rectangle width is
width - Inset::TEXT_TO_INSET_OFFSET
With this change, the spacing on the right of the button is not larger
than the left one.
Fixes bug #10147.
(cherry picked from commit 516d5d29dc)
There is already a spacing of 2 pixels on each side of a button (e.g.
collapsed inset). There is no need to add one extra pixel for command
insets.
Fixes part of bug #10149.
(cherry picked from commit 68149e380d)
As such, it shall be protected in moving arguments, such as sections.
Fixes bug #10092.
(cherry picked from commit 86ee2699c30b63e5b4de3ad725519756d17aec2c)
Those two functions used two different hackish and buggy
implementation to know when the function is disabled. Replace that by
asking the containing inset whether it accepts inserting display math
inset.
Fixes bug #10033.
(cherry picked from commit de5630a1562054cb969b106e35f84bfe1e99002a)
When in a tabular cell, "this" is just a lone InsetText, while cur.inset() is the whole tabular. This makes a big difference, especially when one wants to count cells.
Fixes bug #9954.
(cherry picked from commit 4caf167dbd24722421ae8d94a2c103bf41a7667d)
The old name conflicted with the newly introduced Inset::isTable.
Now the meaning is as follows.
* Inset::isTable() is true when the inset is composed of lines and columns
* InsetMathHull::allowsTabularFeatures is true when the current type of hull allows for tabular-like functions.
(cherry picked from commit db39dc7ccd4c2dd14ef20547e6e3c056ba030d83)
inset-select-all has 3 levels
1. select current cell
2. select all cells
3. select inset from outside.
The second level makes sense for tables (text and math), but not for things like a math fraction.
Introduce a new method Inset::isTable() that allows to detect this case properly and skip level 2.
(cherry picked from commit 5de28b9ac6736c791146a1a3ebe7f4826c22a9b7)
"Output changes" alters the preamble even in the absence of tracked
changes. Therefore, not being able to notice when it is activated can possibly
yield hard-to-debug compilation failures.
(#8738)
For efficiency, we add a new flag to the buffer indicating when changes are
present. This flag is updated at each buffer update, and also when explicitly
requested via a dispatch result flag.
The timer logic introduced to solve bug #7138 was not entirely reliable; in
particular it resulted in spurious updates (noticeable by the treeview
collapsing just after one opens a branch, in particular).
This commit cleans up the timer logic. I followed the original design decision
of having an immediate update followed by a delayed update. Now the updates are
appropriately compressed and done after a delay of 2s (as can be noticed with
the treeview still collapsing, unfortunately, but after a more predictable
delay...).
4d1ad336fixed#9754 but caused perf issues by cancelling the gains of having a
timer (introduced after #7138). This introduces in GuiToc::enableView() a
lightweight check of whether the widget should be updated. The logic is inspired
from GuiViewSource::enableView().
If we do not do that, it is not possible to position the cursor after
a long inset with the mouse.
To do this, it is necessary to add the pit information to the Row
object. This is a good idea in any case, and will allow to simplify
some code later on.
Fixes bug #10094.
(cherry picked from commit 8851645799ef67015e49fd75b9dfeed65d685e85)
When document settings are modified, a command
inset-forall Branch inset-toggle asign
is run to open as needed all branches. At the end of the said loop,
the cursor is reset to where it was. However, the cur_after undo
element member is not set because it already had a value.
To make this work as expected, it is necessary in LFUN_INSET_FORALL to
reset the cursor before ending the undo group and to insert a dummy
recordUndo call.
Fixes bug #10097.
(cherry picked from commit 0036762f30def16ab8b2216f721f9e552893bc85)
Ask the user for removing bindings when using the "restore" button (#9174).
Fix the already-bound-key detection logic.
Don't forget to trigger the search when initializing the search LineEdit with
its former value.
This is done by implementing the clickable method. It is not possible yet to have the usual left and down arrows, because Qt does not implement them as far as I can see.
Factor the code that triggers row/column selection and fix the logic. Now it is possible to select also at the right of the tabular inset.
When several bufferviews exist for the same inset, the data that depends on the view width have to be BufferView-dependent. While this is the case for several mutable members of InsetCollapsable, some were missing.
This commit makes button_dim_ (renamed from button_dim) and openinlined_ bv-dependent.
Get rid of the hitButton function.
Remove the bv-independent geometry() method and implement editable() explicitely instead.
Fixes bug #9756.
"echo -e" is definitely not portable. Use a plain loop instead.
Also use the automake silent rule mechanism to make the generation of monolithic source files visible.
Remove in particular all comparisons < and >= involving HullType.
Add a guard to make sure that mutate() only operates on types it has been
designed for. Then I figured I could use this new knowledge to give feedback
when math-mutate is not implemented via getStatus(). (To test this, insert a
regexp in Advanced Search & Replace and try to change it into a standard
equation via the contextual menu.)
AMS align environment should have some spacing between odd and even columns.
Add a new virtual method displayColSpace() to InsetMathGrid, InsetMathHull and
InsetMathSplit.
A longstanding problem... (related: #1861)
The columns in AMS math environments have a fixed alignment (colAlign() in
InsetMathGrid.cpp). We set this alignment for display (Georg's
displayColAlign()) in InsetMathHull and InsetMathSplit. This is done according
to tests and documentation for the various environments.
There is also some mechanical code factoring via colAlign().
Finally, I disable setting the horizontal alignment in InsetMathSplit, which has
no impact on the LaTeX output, and has no longer any impact on the screen. (As
for vertical alignment I discovered that it was in fact customisable for
\aligned & friends! I hope that the more faithful interface will let other
users discover that too.)
The offending code appears to have been introduced a long time ago. My
understanding is that it is no longer relevant. Notably, it only appears on copy
and not on cut, which tells us that: 1) it should be safe to remove it, 2) we
should remove it for consistency.
While a one paragraph large collapsable inset (containing for example a tabular) could be very wide and trigger horizontal scrolling, the code that makes collapsable insets wide when they contain several paragraphs would actually make them narrower in this case.
Typical example is a wide tabular and a caption in a table float, where horizontal scrolling would not trigger.
(cherry picked from commit a879bc2575)
It is wrong to assume that direction is left-to-right when no indication exist.
Add a new enum with values LtR, RtL and Auto to be used as argument of
the private text() methods. When direction is Auto, let Qt decide how
the string shall be layed out.
This is reimplementation of 51ee267c. A direct cherry-pick was not possible.
Fixes bug #10169.
When the box has a special width, one should not consider that as a fixed width. Otherwise, due to implementation quirks, the width will be set on screen as 1 inch.
A better solution would be to actually set the width by taking in account the contents width, height ans total height. This is not very difficult, but I do not know whether it would workout well in the work area.
Fixes bug #10048.
With Qt 5, our code did not correctly detect when icons were
available and thus tried to use nonexistent icons.
QIcon::hasThemeIcon(theme_icon) returns true when theme_icon is
empty. We now rely on the behavior that QIcon::isNull() returns true
if the icon is empty.
The same code is used with Qt 4 and Qt 5.
This is used when scaling graphics previews. It is also used on a rare occasion
to scale instant previews when the user's configuration mixes low-dpi and
high-dpi monitors (#10114).
With this change, it becomes possible to run the following commands:
inset-forall Separator:latexpar char-delete-forward
inset-forall Separator:parbreak inset-modify separator plain
The first one deletes all latexpar separators. The second one turns parbreak
separators into plain separators. This is safe, flexible, and avoids adding a
new LFUN.
2.1.x allows some document settings to have negative values where
2.2.0rc1 does not (because of the bug fix at 9e166088). If a user of
2.2.0rc1 opens a document from 2.1.x that contains one such negative
value, it will appear as though no change to the document settings
can be saved because 2.2.0rc1 treats the document settings as
invalid immediately on opening the dialog. Further, unless the user
manually goes through each tab they will not see the red text next
to the input that is now considered invalid. This could lead to
confusion for users. One example of such confusion is [1].
The following settings now allow negative values, which is
consistent with 2.1.x. Negative values in these settings do not lead
to LaTeX errors:
- Text Layout tab: the two line edits enabled with "Custom"
- Page Margins tab: all eight line edits
The following settings are not changed by this commit, so they now
(with 2.2.0) do not allow negative values that 2.1.x allowed. This
change makes sense because negative values lead to LaTeX errors in
these cases:
- Page Layout tab: the "Height" and "Width" line edits, which are
enabled when "Custom" is selected
[1] https://www.mail-archive.com/search?l=mid&q=CAGZ2pgXqf27UaAaQ%3De_wFz1fGTa6Yv0iFyS97qu1C7B5R59irg%40mail.gmail.com
An undocumented behaviour of QClipboard::mimeData() is that it can fail on
windows due to the specificities of the windows API that allow a race condition.
In particular it seems that querying the clipboard as soon as the dataChanged()
signal is received favourises this race condition.
Thanks to Trac user bquistorff for the explanation and a proof of concept patch.
This was a regression of 8aa37c43. I did not take into account that end_pos
could be -1, so the code that checked whether a pair of braces needs to be
inserted between two hyphens did not work for that case. Now we check for
the length of text_, which should be done anyway, and only take end_pos into
account when it is not -1.
http://thread.gmane.org/gmane.editors.lyx.devel/161725
These wms have trouble with the fix at b5a2f1c7, probably more precisely with
the trick to force the calculation of the actual sizes before the display
(layout->invalidate() and the code around it).
This patch gets rid of the code that forces the calculation. As a consequence,
the minimum sizes are again incorrect the first time the window is shown. They
are only correct the second time the window is shown. Now here is the trick: LyX
remembers the sizes of windows between sessions. Therefore, as soon as the good
minimum size has been set, the good size is remembered for the next
session. Thus, in the following sessions, even though the minimum size is
incorrect the first time, the dialog still opens with the good size. So the user
does not see the problem in practice, apart from the very first time.
This is meant as a temporary workaround.
* provide GuiApplication::typewriterSystemFont() to get a fixed font consistently
* enlarge fixed font on Mac because of the too small default Qt system font
* use it in source pane, progress view, log view and document preamble editor
Regression at cfeddb929. If a flex inset has no layout upon saving (e.g. if a
module has been deleted) then its name became lost. This checks whether the name
resolution, introduced with the ObsoletedBy tag, comes back empty-handed (which
it will if the layout is not defined). In this case, we do as was done before
cfeddb929.
In addition, the use of support::token to strip "Flex:" off the beginning of the
name introduces a regression if somebody used a name containing ":". This
replaces it with support::split.
This is the same as the parbreak separator and is represented on screen
as the old parbreak. Old parbreak separators are converted to latexpar
separators when they are used for introducing blank lines in the
latex output rather than for separating environments.
Instead, parbreak separators are now represented on screen by a
double line. In essence, latexpar and parbreak separators produce
the same output but are represented differently on screen.
The context menu does not account for latexpar separators and only
"true" separators can be turned each into the other one.
7b1107d7 introduced the following inconveniences which are regressions to 2.1:
* The citation dialog can open with vertical scroll bars in the options
* The citation dialog can open with horizontal scroll bars, especially if the
translated text is longer than the original text (e.g. in FR)
* Resizing the dialog is inconvenient because it increases the gap between the
options. This is unlike before when the dialog could let us see more of the
reference list when enlarging.
This is because the QToolbox that the above commit introduced is not natively
aware of the sizes of its page sub-widgets. The widget is not conceived for this
use, where the space is scarce.
Geometry values provided in the ui file (automatically computed by qtcreator I
suppose) somehow gave the illusion that it worked, but relying on such values is
not portable : it does not take into account the specific theme, font sizes and
localization. This explains why it failed on my side and will probably fail in
other settings too.
Luckily, there is a simple way to make QToolbox suitable for the current use,
which is to add the "missing link" which computes its size based on the minimal
sizes of its pages. The result looks very nice and intuitive. It solves all the
aforementioned issues.
The term LongTable has been deprecated and moreover the renaming makes the interface easier to the eye.
File format updated to 507. (conversion based on jamatos patch)
Layout format updated to 60.
tex2ylx tests updated.
Document EmbeddedObjects.lyx has been updated.
There are two regressions that are fixed here:
* empty rows at the end of a paragraph (think after newline at end of
paragraph or empty line in Verbatim) do not have an end-of-par
marker. This is fixed by removing the early return in breakRow and
letting the whole function be executed. This requires to relax an
assertion in Paragraph::fontSpan. It makes sense here to query
position at the end of the paragraph.
* a newline at the end of a paragraph will be followed by and
end-of-par marker. This is fixed by skipping the end-of-par marker
when a new row has been requested.
The context menu of newline insets was completely greyed out if one clicked
at the right of the inset. Thanks Scott for finding this. The fix is to undo
the cursor movement also for insets without settings, but with a context menu.
According to callgrind, the time taken to display the symbol dialog is spent in
updateSymbolsList. No longer translate strings for every symbol. This speeds
it up more or less by a factor two.
The stmary font has an unusual large descent that was causing a large
gap between lines in the math delimiter dialog because of the \llbracket
and \rrbracket delimiters. The solution is to force Qt using the same
size for all elements of the QlistWidget widget instead of letting it
compute the size of each element.
When a row is broken by for example a display math inset, it is
possible to put the cursor at the end of the previous line using the
boundary setting of cursor.
For newline insets and separator insets, we want to force the cursor
to be before this inset. Also, in the other cases, do not force
boundary property (effectively reverts part of f29e7803).
* breakRow: remove wrong condition that would silently eat the contents of the
paragraph when the window is narrower than left margin
* breakRow: make sure that there is at least one element in each row
* breakAt: when force-breaking a row element, make sure it is not empty. Doing
so may create empty rows and therefore a endless loop.
Fixes bugs #9962 and #10001.
The existing code already avoids merging with typewriter font, but it does not work with LyX-Code, where the typewriter family is inherited. Therefore it is Cursor::real_current_font that must be tested.
Fixes bug #9987.
removeShortcut() restores default settings, therefore was used incorrectly. I
introduce deactivateShortcuts() which only removes assignments.
Clean up a bit the lack of view / model distinction (getting rid of the crashing
code at the same time).
Repair inconsistency of the selection in the "modify" case. (regression at
717d19d3c)
Make the test for existing bindings a bit more robust. (Not perfect yet.)
Focus on the item that has just been added/modified. (cosmetic)
This fixes a failing unit test with 32bit gcc 4.9.3 and -O2 optimization:
It computed 9953 instead of 9954 for Length::inPixels() of value 2342.
The reason for this is probably different rounding behaviour caused by storing
the unrounded value in a processor register (uses 80bit accuracy) vs. writing
it back to memory (uses 64bit accuracy). The unrounded value is very close to
9953.5 (which is not representable as an exact IEEE floating point value).
Apart from that, having a proper function for rounding makes the code more
readable, and has the nice side effect to make Length::inPB() work for
negative lengths as well.
\origin is a transient property in the sense that in a collaborative context
each co-author is going to have a different value for it. Moreover, \save_origin
is a global (lyxrc) setting that cannot yet be deactivated for a single file,
but one author's setting is going to impact other authors, even those who have
set save_origin=false.
There is only one location where lyxrc.save_origin produces an effect, modified
by this patch. With this patch, everything happens as if lyxrc.save_origin was
false whenever save_transient_properties=false.
This is not a file format change. When a file has
save_transient_properties=false but an origin is set (for instance a file
produced before this patch) then the origin produces its effect before the file
is saved. This produces the same effect as if the user decided to disable
save_origin between two sessions.
This concerns InsetPreview, InsetIPA and InsetMathHull.
Caching such a value is bad when opening the same buffer in two views.
In this case, it is not necessary to remember use_preview_ at all,
actually.
Also remove private member dim_ which is not used and remove some trailing whitespace.
Fixes bugs #9085 abd #9957.
Since the low-level version of tabular features is only called by the high-level one, it does not make sense to record undo there. It is much better to do it once in the high-level handler, rather than 37 times (yes!) at lower level when the tabular GUI calls tabular-feature with all the settings at once.
With large tables, this avoids to keep 37 copies of the table in Undo stack.
As an added bonus, this fixes bug #9960.
When an inset is separated from the adjacent string by a space, it is
reasonable to be able to break the string after the space.
Unfortunately, QTextLayout does not do that.
This patch reverts the workaround inserted in 71378268 and replaces it
with a different trick: the string is enlosed between a pair of
zero-width non breaking space characters, so that the leading/trailing
spaces are now normal spaces, where QTextLayout will agree to break
the string.
Fixes bug #9921 for good.
We open the input file now twice: The first time in latin1 encoding to read
the document encoding from the preamble. This does always work, since
traditional TeX does not allow non-ASCII contents without an encoding changing
command (except for comments, but we do not need them, and using latin1 rather
than utf8 ensures that they do not produce an iconv exception, but are simply
recored with wrong characters), and we do detect the utf8 based TeX engines
XeTeX and LuaTeX as well. The second time we open the file directly with the
document encoding.
This fixes a few tex2lyx tests on OS X, since changing the encoding of an
open file steam does not work with clang on OS X. Files using more than one
encoding are still broken, but all single-encoding files are fixed now.
Changing the codecvt_facet of a file stream after the file has been opened
does not work with clang on OS X. Therefore we avoid it if possible (i. e. the
new encoding is the same as the old one).
This does not make any difference currently, since the only instance of the
Preamble class is a global one, but it is cleaner and will be needed for
parsing the encoding with a second Preamble instance.
This is a fixup to commit cdb9f043, which fixed bug #9757.
It is necessary to make a special case for inserting an InsetCaption
in a tabular cell, because this commonly happens in longtable mode.
Fixes bug #9945.
* Increase LyX format
* New function convert_info_insets in lyx2lyx_tools.py
Use this function in the future for future updates of info insets
* Convert "inset-modify tabular" to "tabular-feature" in info insets
* Remove icon naming hack regarding "inset-modify tabular"
The tabular-features LFUN was merged with "inset-modify tabular" when
simplifying the tabular dialog at b5049e7. This choice later indirectly caused a
few regressions (#7308, #9794).
I reintroduce tabular-feature to allow more flexibility for user
commands, whereas "inset-modify tabular" is now reserved for the tabular
dialog. In particular, inset-modify tabular is no longer caught by math grid
insets. The name tabular-feature is kept to avoid renaming icons.
Known issues:
* After successfully applying a tabular command, the cursor is truncated to the
table.
* Note that the tabular dialog still has similar issues that are inherited from
the achitecture of the dialog menu. For instance the pref change can be
mis-dispatched to an inset inside a cell and cause an error, for instance:
Lexer.cpp (934): Missing 'Note'-tag in InsetNote::string2params. Got
tabular instead. Line: 0
Maybe the inset-modify LFUN should be modified to treat commands coming from
the wrong dialog (by checking the type) as unknown and undispatched so that
the parent can get it. In that case a non AtPoint variant of inset-modify
could be reintroduced in order to generalise tabular-feature. See:
http://mid.gmane.org/n4rdk1$efj$1@ger.gmane.org
External processes cannot access files which are open in LyX. Therefore the
temp files created by the external inset need to be closed right after
creation. The symptom was that the date inset did not produce any outout on
windows (bug 9925). This change reverts a small part of f09a9fe2.
Although the date inset is unimportant and will probably be removed, this
change is important for all external insets that make use of temp files.
Unfortunately the footmisc package does not work together with hyperref:
Before 0bf8b8a1, a footnote in a section title was created as a link in pdf
outpout, after 0bf8b8a1 ist was no link anymore. For now we revert to the old
code, and wait until the footmisc and hyperref packages are made compatible.
The important thing is actually not the date inset, but the converter
machinery, which did convert the time stamps of two unused freshly created
temp files, which does not make sense, and did work before f09a9fe2 only by
accident.
This fixes the date inset on linuy, but not on windows, probably due to
different file locking semantics.
AMS align environment should have some spacing between odd and even columns.
Add a new virtual method displayColSpace() to InsetMathGrid, InsetMathHull and
InsetMathSplit.
I have no clue why this was automatically committed, I just applied the path, nothing more.
This reverts commit bb5470b5d1.
# Conflicts:
# src/mathed/InsetMathGrid.cpp
# src/mathed/InsetMathSplit.cpp
AMS align environment should have some spacing between odd and even columns.
Add a new virtual method displayColSpace() to InsetMathGrid, InsetMathHull and
InsetMathSplit.
A longstanding problem... (related: #1861)
The columns in AMS math environments have a fixed alignment (colAlign() in
InsetMathGrid.cpp). We set this alignment for display (Georg's
displayColAlign()) in InsetMathHull and InsetMathSplit. This is done according
to tests and documentation for the various environments.
There is also some mechanical code factoring via colAlign().
Finally, I disable setting the horizontal alignment in InsetMathSplit, which has
no impact on the LaTeX output, and has no longer any impact on the screen. (As
for vertical alignment I discovered that it was in fact customisable for
\aligned & friends! I hope that the more faithful interface will let other
users discover that too.)
When hitting Enter after a non-standard layout a plain separator is
now inserted. This seems to be preferred and more in line with what
is obtained with the "Alt+M P" shortcut.
Increment LyX format to 504.
With this new parameter, the user can indicate that some other parameters that
are frequently switched must not be recorded in the file (as if they were a
setting specific to the user or transient, rather than a document setting). This
will play nicer with version control systems.
See the discussion, e.g.:
http://thread.gmane.org/gmane.editors.lyx.devel/157824/focus=157993 (third
solution mentioned)
TODO:
* The interface remains to be set up. We cannot change this setting from LyX
for now.
* If save_transient_properties is false, we should read the user setting as a
per-user-per-document (session) setting (e.g. like the cursor position).
* Once the above is done, we can treat \justification the same way (but it would
be even better if \justification was moved to lyxrc).
The current behaviour of the \origin parameter replaces relative file names
with the absolute original names if a document has been moved even if the
files have been moved as well. This behaviour is annoying e.g. for editing the
LyX docs in a git checkout.
Now file names are only replaced if the referenced file sdo not exist.
Simplify the logic for language package selection and make it more consistent:
Use polyglossia with non-TeX fonts (system fonts/Unicode fonts) for all
export flavours (XeTeX, LuaTeX, DVI-LuaTeX), if the language package setting
is "auto" and there is no language not supported by Babel and no package
providing Babel.
This solves some Babel-related autotest cases and leads to some new failures
due to the polyglossia language nesting problem.
The lib/unicodesymbols part is based on work by Günter Milde:
Both, \r{A} and \AA (rsp. \r{a} and \aa) are equivalent standard LICR macros
for Aring/aring as well as the deprecated "angstrom sign" character (212B).
However, with \AA for 212B and \r{A} for 00C5, tex2lyx converts \AA to the
deprecated "angstrom sign" which is missing in many fonts including the
Unicode version of Latin Modern.
I added the normalize_c() calls so that tex2lyx prefers the precomposed forms
(these are better editable in LyX) and the deprecated flag.
The conversion is not completely correct yet, but adding the test before the
fix has the advantage that the fix can easily be documented by changing the
test reference.
whose children is also a child of another buffer, then try to close that
one.
The problem is that we do not check properly to make sure that the child
is not a child of some other buffer. Now we do.
whether a given child Buffer is also a child of some other parent.
Then do the releasing or resetting where this method is called.
There should be no change of behavior with this patch.
Improve the test whether cursor has moved in Cursor::posVisLeft. The code for posVisRight had already been fixed for #5764 at 0730c923, but this replaces both tests by the proper == operator.
Fixes bug #9913.
By initializing 'to' to a value, the code made it seem like that
value mattered. But the value is overwritten in getWord().
Further, now if 'to' is used before it is initialized, there might
be a useful compiler warning that could point to a bug.
Gcc STL debugging feature asserts when swapping an object with itself. This happens in some cases with math grids that have only one column.
A quick review of other uses of swap() in the code base did not reveal any other dubious case.
Fixes bug #9902.
