## Summary of the Pull Request
In the original implementation, we used two different orderings for the color tables. The WT color table used ANSI order, while the conhost color table used a Windows-specific order. This PR standardizes on the ANSI color order everywhere, so the usage of indexed colors is consistent across both parts of the code base, which will hopefully allow more of the code to be shared one day.
## References
This is another small step towards de-duplicating `AdaptDispatch` and `TerminalDispatch` for issue #3849, and is essentially a followup to the SGR dispatch refactoring in PR #6728.
## PR Checklist
* [x] Closes#11461
* [x] CLA signed.
* [x] Tests added/passed
* [ ] Documentation updated.
* [ ] Schema updated.
* [x] I've discussed this with core contributors already. Issue number where discussion took place: #11461
## Detailed Description of the Pull Request / Additional comments
Conhost still needs to deal with legacy attributes using Windows color order, so those values now need to be transposed to ANSI colors order when creating a `TextAttribute` object. This is done with a simple mapping table, which also handles the translation of the default color entries, so it's actually slightly faster than the original code.
And when converting `TextAttribute` values back to legacy console attributes, we were already using a mapping table to handle the narrowing of 256-color values down to 16 colors, so we just needed to adjust that table to account for the translation from ANSI to Windows, and then could make use of the same table for both 256-color and 16-color values.
There are also a few places in conhost that read from or write to the color tables, and those now need to transpose the index values. I've addressed this by creating separate `SetLegacyColorTableEntry` and `GetLegacyColorTableEntry` methods in the `Settings` class which take care of the mapping, so it's now clearer in which cases the code is dealing with legacy values, and which are ANSI values.
These methods are used in the `SetConsoleScreenBufferInfoEx` and `GetConsoleScreenBufferInfoEx` APIs, as well as a few place where color preferences are handled (the registry, shortcut links, and the properties dialog), none of which are particularly sensitive to performance. However, we also use the legacy table when looking up the default colors for rendering (which happens a lot), so I've refactored that code so the default color calculations now only occur once per frame.
The plus side of all of this is that the VT code doesn't need to do the index translation anymore, so we can finally get rid of all the calls to `XTermToWindowsIndex`, and we no longer need a separate color table initialization method for conhost, so I was able to merge a number of color initialization methods into one. We also no longer need to translate from legacy values to ANSI when generating VT sequences for conpty.
The one exception to that is the 16-color VT renderer, which uses the `TextColor::GetLegacyIndex` method to approximate 16-color equivalents for RGB and 256-color values. Since that method returns a legacy index, it still needs to be translated to ANSI before it can be used in a VT sequence. But this should be no worse than it was before.
One more special case is conhost's secret _Color Selection_ feature. That uses `Ctrl`+Number and `Alt`+Number key sequences to highlight parts of the buffer, and the mapping from number to color is based on the Windows color order. So that mapping now needs to be transposed, but that's also not performance sensitive.
The only thing that I haven't bothered to update is the trace logging code in the `Telemetry` class, which logs the first 16 entries in the color table. Those entries are now going to be in a different order, but I didn't think that would be of great concern to anyone.
## Validation Steps Performed
A lot of unit tests needed to be updated to use ANSI color constants when setting indexed colors, where before they might have been expecting values in Windows order. But this replaced a wild mix of different constants, sometimes having to use bit shifting, as well as values mapped with `XTermToWindowsIndex`, so I think the tests are a whole lot clearer now. Only a few cases have been left with literal numbers where that seemed more appropriate.
In addition to getting the unit tests working, I've also manually tested the behaviour of all the console APIs which I thought could be affected by these changes, and confirmed that they produced the same results in the new code as they did in the original implementation.
This includes:
- `WriteConsoleOutput`
- `ReadConsoleOutput`
- `SetConsoleTextAttribute` with `WriteConsoleOutputCharacter`
- `FillConsoleOutputAttribute` and `FillConsoleOutputCharacter`
- `ScrollConsoleScreenBuffer`
- `GetConsoleScreenBufferInfo`
- `GetConsoleScreenBufferInfoEx`
- `SetConsoleScreenBufferInfoEx`
I've also manually tested changing colors via the console properties menu, the registry, and shortcut links, including setting default colors and popup colors. And I've tested that the "Quirks Mode" is still working as expected in PowerShell.
In terms of performance, I wrote a little test app that filled a 80x9999 buffer with random color combinations using `WriteConsoleOutput`, which I figured was likely to be the most performance sensitive call, and I think it now actually performs slightly better than the original implementation.
I've also tested similar code - just filling the visible window - with SGR VT sequences of various types, and the performance seems about the same as it was before.
## Summary of the Pull Request
This adds a new setting `intenseTextStyle`. It's a per-appearance, control setting, defaulting to `"all"`.
* When set to `"all"` or `["bold", "bright"]`, then we'll render text as both **bold** and bright (1.10 behavior)
* When set to `"bold"`, `["bold"]`, we'll render text formatted with `^[[1m` as **bold**, but not bright
* When set to `"bright"`, `["bright"]`, we'll render text formatted with `^[[1m` as bright, but not bold. This is the pre 1.10 behavior
* When set to `"none"`, we won't do anything special for it at all.
## references
* I last did this in #10648. This time it's an enum, so we can add bright in the future. It's got positive wording this time.
* ~We will want to add `"bright"` as a value in the future, to disable the auto intense->bright conversion.~ I just did that now.
* #5682 is related
## PR Checklist
* [x] Closes#10576
* [x] I seriously don't think we have an issue for "disable intense is bright", but I'm not crazy, people wanted that, right? https://github.com/microsoft/terminal/issues/2916#issuecomment-544880423 was the closest
* [x] I work here
* [x] Tests added/passed
* [x] https://github.com/MicrosoftDocs/terminal/pull/381
## Validation Steps Performed
<!--  -->
Yea that works. Printed some bold text, toggled it on, the text was no longer bold. hooray.
### EDIT, 10 Aug
```json
"intenseTextStyle": "none",
"intenseTextStyle": "bold",
"intenseTextStyle": "bright",
"intenseTextStyle": "all",
"intenseTextStyle": ["bold", "bright"],
```
all work now. Repro script:
```sh
printf "\e[1m[bold]\e[m[normal]\e[34m[blue]\e[1m[bold blue]\e[m\n"
```
I was watching a video about vectorized instructions and I wanted to
try out some new things, as I had never written AVX code before.
This commit is the result of this tiny Thursday morning detour into
AVX land. It improves performance of `TextColor::GetColor` by about 3x.
## Validation Steps Performed
* Default colors are still properly shifted +8 ✔️
## Summary of the Pull Request
Introduces `til::rle`, a vector-like container which stores elements of
type T in a run length encoded format. This allows efficient compaction
of repeated elements within the vector.
## References
* #8000 - Supports buffer rewrite work. A re-use of `til::rle` will be
useful as a column counter as we pursue NxM storage and presentation.
* #3075 - The new iterators allow skipping forward by multiple units,
which wasn't possible under `TextBuffer-/OutputCellIterator`.
Additionally it also allows a bulk insertions.
* #8787 and #410 - High probability this should be `pmr`-ified
like `bitmap` for things like `chafa` and `cacafire`
which are changing the run length frequently.
## PR Checklist
* [x] Closes#8741
* [x] I work here.
* [x] Tests added.
* [x] Tests passed.
## Validation Steps Performed
* [x] Ran `cacafire` in `OpenConsole.exe` and it looked beautiful
* [x] Ran new suite of `RunLengthEncodingTests.cpp`
Co-authored-by: Michael Niksa <miniksa@microsoft.com>
This PR adds support for the _blink_ graphic rendition attribute. When a
character is output with this attribute set, it "blinks" at a regular
interval, by cycling its color between the normal rendition and a dimmer
shade of that color.
The majority of the blinking mechanism is encapsulated in a new
`BlinkingState` class, which is shared between the Terminal and Conhost
implementations. This class keeps track of the position in the blinking
cycle, which determines whether characters are rendered as normal or
faint.
In Windows Terminal, the state is stored in the `Terminal` class, and in
Conhost it's stored in the `CONSOLE_INFORMATION` class. In both cases,
the `IsBlinkingFaint` method is used to determine the current blinking
rendition, and that is passed on as a parameter to the
`TextAttribute::CalculateRgbColors` method when these classes are
looking up attribute colors.
Prior to calculating the colors, the current attribute is also passed to
the `RecordBlinkingUsage` method, which keeps track of whether there are
actually any blink attributes in use. This is used to determine whether
the screen needs to be refreshed when the blinking cycle toggles between
the normal and faint renditions.
The refresh itself is handled by the `ToggleBlinkingRendition` method,
which is triggered by a timer. In Conhost this is just piggybacking on
the existing cursor blink timer, but in Windows Terminal it needs to
have its own separate timer, since the cursor timer is reset whenever a
key is pressed, which is not something we want for attribute blinking.
Although the `ToggleBlinkingRendition` is called at the same rate as the
cursor blinking, we actually only want the cells to blink at half that
frequency. We thus have a counter that cycles through four phases, and
blinking is rendered as faint for two of those four. Then every two
cycles - when the state changes - a redraw is triggered, but only if
there are actually blinking attributes in use (as previously recorded).
As mentioned earlier, the blinking frequency is based on the cursor
blink rate, so that means it'll automatically be disabled if a user has
set their cursor blink rate to none. It can also be disabled by turning
off the _Show animations in Windows_ option. In Conhost these settings
take effect immediately, but in Windows Terminal they only apply when a
new tab is opened.
This PR also adds partial support for the `SGR 6` _rapid blink_
attribute. This is not used by DEC terminals, but was defined in the
ECMA/ANSI standards. It's not widely supported, but many terminals just
it implement it as an alias for the regular `SGR 5` blink attribute, so
that's what I've done here too.
## Validation Steps Performed
I've checked the _Graphic rendition test pattern_ in Vttest, and
compared our representation of the blink attribute to that of an actual
DEC VT220 terminal as seen on [YouTube]. With the right color scheme
it's a reasonably close match.
[YouTube]: https://www.youtube.com/watch?v=03Pz5AmxbE4&t=1m55sCloses#7388
<!-- Enter a brief description/summary of your PR here. What does it fix/what does it change/how was it tested (even manually, if necessary)? -->
## Summary of the Pull Request
Conhost can now support OSC8 sequences (as specified [here](https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda)). Terminal also supports those sequences and additionally hyperlinks can be opened by Ctrl+LeftClicking on them.
<!-- Other than the issue solved, is this relevant to any other issues/existing PRs? -->
## References
#204
<!-- Please review the items on the PR checklist before submitting-->
## PR Checklist
* [X] Closes#204
* [ ] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [ ] Tests added/passed
* [ ] Documentation updated. If checked, please file a pull request on [our docs repo](https://github.com/MicrosoftDocs/terminal) and link it here: #xxx
* [ ] Schema updated.
* [ ] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx
<!-- Provide a more detailed description of the PR, other things fixed or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments
Added support to:
- parse OSC8 sequences and extract URIs from them (conhost and terminal)
- add hyperlink uri data to textbuffer/screeninformation, associated with a hyperlink id (conhost and terminal)
- attach hyperlink ids to text to allow for uri extraction from the textbuffer/screeninformation (conhost and terminal)
- process ctrl+leftclick to open a hyperlink in the clicked region if present
<!-- Describe how you validated the behavior. Add automated tests wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed
Open up a PowerShell tab and type
```PowerShell
${ESC}=[char]27
Write-Host "${ESC}]8;;https://github.com/microsoft/terminal${ESC}\This is a link!${ESC}]8;;${ESC}\"
```
Ctrl+LeftClick on the link correctly brings you to the terminal page on github
This PR adds support for the ANSI _doubly underlined_ graphic rendition
attribute, which is enabled by the `SGR 21` escape sequence.
There was already an `ExtendedAttributes::DoublyUnderlined` flag in the
`TextAttribute` class, but I needed to add `SetDoublyUnderlined` and
`IsDoublyUnderlined` methods to access that flag, and update the
`SetGraphicsRendition` methods of the two dispatchers to set the
attribute on receipt of the `SGR 21` sequence. I also had to update the
existing `SGR 24` handler to reset _DoublyUnderlined_ in addition to
_Underlined_, since they share the same reset sequence.
For the rendering, I've added a new grid line type, which essentially
just draws an additional line with the same thickness as the regular
underline, but slightly below it - I found a gap of around 0.05 "em"
between the lines looked best. If there isn't enough space in the cell
for that gap, the second line will be clamped to overlap the first, so
you then just get a thicker line. If there isn't even enough space below
for a thicker line, we move the offset _above_ the first line, but just
enough to make it thicker.
The only other complication was the update of the `Xterm256Engine` in
the VT renderer. As mentioned above, the two underline attributes share
the same reset sequence, so to forward that state over conpty we require
a slightly more complicated process than with most other attributes
(similar to _Bold_ and _Faint_). We first check whether either underline
attribute needs to be turned off to send the reset sequence, and then
check individually if each of them needs to be turned back on again.
## Validation Steps Performed
For testing, I've extended the existing attribute tests in
`AdapterTest`, `VTRendererTest`, and `ScreenBufferTests`, to make sure
we're covering both the _Underlined_ and _DoublyUnderlined_ attributes.
I've also manually tested the `SGR 21` sequence in conhost and Windows
Terminal, with a variety of fonts and font sizes, to make sure the
rendering was reasonably distinguishable from a single underline.
Closes#2916
This PR updates the rendering of the _underlined_ graphic rendition
attribute, using the style specified in the active font, instead of just
reusing the grid line at the bottom of the character cell.
* Support for drawing the correct underline effect in the grid line
renderer was added in #7107.
There was already an `ExtendedAttributes` flag defined for the
underlined state, but I needed to update the `SetUnderlined` and
`IsUnderlined` methods in the `TextAttribute` class to use that flag
now in place of the legacy `LVB_UNDERSCORE` attribute. This enables
underlines set via a VT sequence to be tracked separately from
`LVB_UNDERSCORE` grid lines set via the console API.
I then needed to update the `Renderer::s_GetGridlines` method to
activate the `GridLines::Underline` style when the `Underlined`
attribute was set. The `GridLines::Bottom` style is still triggered by
the `LVB_UNDERSCORE` attribute to produce the bottom grid line effect.
Validation
----------
Because this is a change from the existing behaviour, certain unit tests
that were expecting the `LVB_UNDERSCORE` to be toggled by `SGR 4` and
`SGR 24` have now had to be updated to check the `Underlined` flag
instead.
There were also some UI Automation tests that were checking for `SGR 4`
mapping to `LVB_UNDERSCORE` attribute, which I've now substituted with a
test of the `SGR 53` overline attribute mapping to
`LVB_GRID_HORIZONTAL`. These tests only work with legacy attributes, so
they can't access the extended underline state, and I thought a
replacement test that covered similar ground would be better than
dropping the tests altogether.
As far as the visual rendering is concerned, I've manually confirmed
that the VT underline sequences now draw the underline in the correct
position and style, while grid lines output via the console API are
still displayed in their original form.
Closes#2915
## Summary of the Pull Request
Text can have various attributes, such as "bold", "italic", "underlined", etc. The TextAttribute class embodies this. It has methods to set/query these attributes.
This change tweaks a few of the method names to make them match. I.e. for an imaginary text property "Foo", we should have methods along the lines of:
```
IsFoo
SetFoo(bool isFoo)
```
And variations should match: we should have "Foo" and "OverFoo", not "Fooey" and "OverFoo".
I chose to standardize on the adjective form, since that's what we are closest to already. The attributes I attacked here are:
SetItalic**s** --> SetItalic
SetUnderline --> SetUnderline**d**
SetOverline --> SetOverline**d**
("italic" is an adjective; "italics" is a plural noun, representing letters or words in an italic typeface)
And I also added methods for "DoublyUnderlined" for good measure.
I stopped short of renaming the GraphicsOptions enum values to match, too; but I'd be willing to do that in a follow-up change if people wanted it.
## Validation Steps Performed
It builds, and tests still pass.
We were using std::basic_string_view as a stand-in for std::span so that
we could change over all at once when C++20 dropped with full span
support. That day's not here yet, but as of 54a7fce3e we're using GSL 3,
whose span is C++20-compliant.
This commit replaces every instance of basic_string_view that was not
referring to an actual string with a span of the appropriate type.
I moved the `const` qualifier into span's `T` because while
`basic_string_view.at()` returns `const T&`, `span.at()` returns `T&`
(without the const). I wanted to maintain the invariant that members of
the span were immutable.
* Mechanical Changes
* `sv.at(x)` -> `gsl::at(sp, x)`
* `sv.c{begin,end}` -> `sp.{begin,end}` (span's iterators are const)
I had to replace a `std::basic_string<>` with a `std::vector<>` in
ConImeInfo, and I chose to replace a manual array walk in
ScreenInfoUiaProviderBase with a ranged-for. Please review those
specifically.
This will almost certainly cause a code size regression in Windows
because I'm blowing out all the PGO counts. Whoops.
Related: #3956, #975.
## Summary of the Pull Request
This PR adds support for the `SGR 8` and `SGR 28` escape sequences,
which enable and disable the _concealed/invisible_ graphic rendition
attribute. When a character is output with this attribute set, it is
rendered with the same foreground and background colors, so the text is
essentially invisible.
## PR Checklist
* [x] Closes#6876
* [x] CLA signed.
* [x] Tests added/passed
* [ ] Documentation updated.
* [ ] Schema updated.
* [x] I've discussed this with core contributors already. Issue number
where discussion took place: #6876
## Detailed Description of the Pull Request / Additional comments
Most of the framework for this attribute was already implemented, so it
was just a matter of updating the `TextAttribute::CalculateRgbColors`
method to make the foreground the same as the background when the
_Invisible_ flag was set. Note that this has to happen after the
_Reverse Video_ attribute is applied, so if you have white-on-black text
that is reversed and invisible, it should be all white, rather than all
black.
## Validation Steps Performed
There were already existing SGR unit tests covering this attribute in
the `ScreenBufferTests`, and the `VtRendererTest`. But I've added to the
`AdapterTest` which verifies the SGR sequences for setting and resetting
the attribute, and I've extended the `TextAttributeTests` to verify that
the color calculations return the correct values when the attribute is
set.
I've also manually confirmed that we now render the _concealed text_
values correctly in the _ISO 6429_ tests in Vttest. And I've manually
tested the output of _concealed_ when combined with other attributes,
and made sure that we're matching the behaviour of most other terminals.
## Summary of the Pull Request
This PR adds support for the `SGR 2` escape sequence, which enables the
ANSI _faint_ graphic rendition attribute. When a character is output
with this attribute set, it uses a dimmer version of the active
foreground color.
## PR Checklist
* [x] Closes#6703
* [x] CLA signed.
* [x] Tests added/passed
* [ ] Documentation updated.
* [ ] Schema updated.
* [x] I've discussed this with core contributors already. Issue number where discussion took place: #6703
## Detailed Description of the Pull Request / Additional comments
There was already an `ExtendedAttributes::Faint` flag in the
`TextAttribute` class, but I needed to add `SetFaint` and `IsFaint`
methods to access that flag, and update the `SetGraphicsRendition`
methods of the two dispatchers to set the attribute on receipt of the
`SGR 2` sequence. I also had to update the existing `SGR 22` handler to
reset _Faint_ in addition to _Bold_, since they share the same reset
sequence. For that reason, I thought it a good idea to change the name
of the `SGR 22` enum to `NotBoldOrFaint`.
For the purpose of rendering, I've updated the
`TextAttribute::CalculateRgbColors` method to return a dimmer version of
the foreground color when the _Faint_ attribute is set. This is simply
achieved by dividing each color component by two, which produces a
reasonable effect without being too complicated. Note that the _Faint_
effect is applied before _Reverse Video_, so if the output it reversed,
it's the background that will be faint.
The only other complication was the update of the `Xterm256Engine` in
the VT renderer. As mentioned above, _Bold_ and _Faint_ share the same
reset sequence, so to forward that state over conpty we have to go
through a slightly more complicated process than with other attributes.
We first check whether either attribute needs to be turned off to send
the reset sequence, and then check if the individual attributes need to
be turned on again.
## Validation
I've extended the existing SGR unit tests to cover the new attribute in
the `AdapterTest`, the `ScreenBufferTests`, and the `VtRendererTest`,
and added a test to confirm the color calculations when _Faint_ is set
in the `TextAttributeTests`.
I've also done a bunch of manual testing with all the different VT color
types and confirmed that our output is comparable to most other
terminals.
This is a refactoring of the renderer color calculations to simplify the
implementation, and to make it easier to support additional
color-altering rendition attributes in the future (e.g. _faint_ and
_conceal_).
## References
* This is a followup to PRs #3817 and #6809, which introduced additional
complexity in the color calculations, and which suggested the need for
refactoring.
## Detailed Description of the Pull Request / Additional comments
When we added support for `DECSCNM`, that required the foreground and
background color lookup methods to be able to return the opposite of
what was requested when the reversed mode was set. That made those
methods unnecessarily complicated, and I thought we could simplify them
considerably just by combining the calculations into a single method
that derived both colors at the same time.
And since both conhost and Windows Terminal needed to perform the same
calculations, it also made sense to move that functionality into the
`TextAttribute` class, where it could easily be shared.
In general this way of doing things is a bit more efficient. However, it
does result in some unnecessary work when only one of the colors is
required, as is the case for the gridline painter. So to make that less
of an issue, I've reordered the gridline code a bit so it at least
avoids looking up the colors when no gridlines are needed.
## Validation Steps Performed
Because of the API changes, quite a lot of the unit tests had to be
updated. For example instead of verifying colors with two separate calls
to `LookupForegroundColor` and `LookupBackgroundColor`, that's now
achieved with a single `LookupAttributeColors` call, comparing against a
pair of values. The specifics of the tests haven't changed though, and
they're all still working as expected.
I've also manually confirmed that the various color sequences and
rendition attributes are rendering correctly with the new refactoring.
There is going to be a very long tail of applications that will
explicitly request VT SGR 40/37 when what they really want is to
SetConsoleTextAttribute() with a black background/white foreground.
Instead of making those applications look bad (and therefore making us
look bad, because we're releasing this as an update to something that
"looks good" already), we're introducing this compatibility quirk.
Before the color reckoning in #6698 + #6506, *every* color was subject
to being spontaneously and erroneously turned into the default color.
Now, only the 16-color palette value that matches the active console
background/foreground color will be destroyed, and only when received
from specific applications.
Removal will be tracked by #6807.
Michael and I discussed what layer this quirk really belonged in. I
originally believed it would be sufficient to detect a background color
that matched the legacy default background, but @j4james provided an
example of where that wouldn't work out (powershell setting the
foreground color to white/gray). In addition, it was too heavyhanded: it
re-broke black backgrounds for every application.
Michael thought that it should live in the server, as a small VT parser
that righted the wrongs coming directly out of the application. On
further investigation, however, I realized that we'd need to push more
information up into the server (so that it could make the decision about
which VT was wrong and which was right) than should be strictly
necessary.
The host knows which colors are right and wrong, and it gets final say
in what ends up in the buffer.
Because of that, I chose to push the quirk state down through
WriteConsole to DoWriteConsole and toggle state on the
SCREEN_INFORMATION that indicates whether the colors coming out of the
application are to be distrusted. This quirk _only applies to pwsh.exe
and powershell.exe._
NOTE: This doesn't work for PowerShell the .NET Global tool, because it
is run as an assembly through dotnet.exe. I have no opinion on how to
fix this, or whether it is worth fixing.
VALIDATION
----------
I configured my terminals to have an incredibly garish color scheme to
show exactly what's going to happen as a result of this. The _default
terminal background_ is purple or red, and the foreground green. I've
printed out a heap of test colors to see how black interacts with them.
Pull request #6810 contains the images generated from this test.
The only color lines that change are the ones where black as a
background or white as a foreground is selected out of the 16-color
palette explicitly. Reverse video still works fine (because black is in
the foreground!), and it's even possible to represent "black on default"
and reverse it into "default on black", despite the black in question
having been `40`.
Fixes#6767.
## Summary of the Pull Request
This PR adds support for the `SGR 53` and `SGR 55` escapes sequences,
which enable and disable the ANSI _overline_ graphic rendition
attribute, the equivalent of the console character attribute
`COMMON_LVB_GRID_HORIZONTAL`. When a character is output with this
attribute set, a horizontal line is rendered at the top of the character
cell.
## PR Checklist
* [x] Closes#6000
* [x] CLA signed.
* [x] Tests added/passed
* [ ] Documentation updated.
* [ ] Schema updated.
* [x] I've discussed this with core contributors already.
## Detailed Description of the Pull Request / Additional comments
To start with, I added `SetOverline` and `IsOverlined` methods to the
`TextAttribute` class, to set and get the legacy
`COMMON_LVB_GRID_HORIZONTAL` attribute. Technically there was already an
`IsTopHorizontalDisplayed` method, but I thought it more readable to add
a separate `IsOverlined` as an alias for that.
Then it was just a matter of adding calls to set and reset the attribute
in response to the `SGR 53` and `SGR 55` sequences in the
`SetGraphicsRendition` methods of the two dispatchers. The actual
rendering was already taken care of by the `PaintBufferGridLines` method
in the rendering engines.
The only other change required was to update the `_UpdateExtendedAttrs`
method in the `Xterm256Engine` of the VT renderer, to ensure the
attribute state would be forwarded to the Windows Terminal over conpty.
## Validation Steps Performed
I've extended the existing SGR unit tests to cover the new attribute in
the `AdapterTest`, the `OutputEngineTest`, and the `VtRendererTest`.
I've also manually tested the `SGR 53` and `SGR 55` sequences to confirm
that they do actually render (or remove) an overline on the characters
being output.
This PR reimplements the VT rendering engines to do a better job of
preserving the original color types when propagating attributes over
ConPTY. For the 16-color renderers it provides better support for
default colors and improves the efficiency of the color narrowing
conversions. It also fixes problems with the ordering of character
renditions that could result in attributes being dropped.
Originally the base renderer would calculate the RGB color values and
legacy/extended attributes up front, passing that data on to the active
engine's `UpdateDrawingBrushes` method. With this new implementation,
the renderer now just passes through the original `TextAttribute` along
with an `IRenderData` interface, and leaves it to the engines to extract
the information they need.
The GDI and DirectX engines now have to lookup the RGB colors themselves
(via simple `IRenderData` calls), but have no need for the other
attributes. The VT engines extract the information that they need from
the `TextAttribute`, instead of having to reverse engineer it from
`COLORREF`s.
The process for the 256-color Xterm engine starts with a check for
default colors. If both foreground and background are default, it
outputs a SGR 0 reset, and clears the `_lastTextAttribute` completely to
make sure any reset state is reapplied. With that out the way, the
foreground and background are updated (if changed) in one of 4 ways.
They can either be a default value (SGR 39 and 49), a 16-color index
(using ANSI or AIX sequences), a 256-color index, or a 24-bit RGB value
(both using SGR 38 and 48 sequences).
Then once the colors are accounted for, there is a separate step that
handles the character rendition attributes (bold, italics, underline,
etc.) This step must come _after_ the color sequences, in case a SGR
reset is required, which would otherwise have cleared any character
rendition attributes if it came last (which is what happened in the
original implementation).
The process for the 16-color engines is a little different. The target
client in this case (Windows telnet) is incapable of setting default
colors individually, so we need to output an SGR 0 reset if _either_
color has changed to default. With that out the way, we use the
`TextColor::GetLegacyIndex` method to obtain an approximate 16-color
index for each color, and apply the bold attribute by brightening the
foreground index (setting bit 8) if the color type permits that.
However, since Windows telnet only supports the 8 basic ANSI colors, the
best we can do for bright colors is to output an SGR 1 attribute to get
a bright foreground. There is nothing we can do about a bright
background, so after that we just have to drop the high bit from the
colors. If the resulting index values have changed from what they were
before, we then output ANSI 8-color SGR sequences to update them.
As with the 256-color engine, there is also a final step to handle the
character rendition attributes. But in this case, the only supported
attributes are underline and reversed video.
Since the VT engines no longer depend on the active color table and
default color values, there was quite a lot of code that could now be
removed. This included the `IDefaultColorProvider` interface and
implementations, the `Find(Nearest)TableIndex` functions, and also the
associated HLS conversion and difference calculations.
VALIDATION
Other than simple API parameter changes, the majority of updates
required in the unit tests were to correct assumptions about the way the
colors should be rendered, which were the source of the narrowing bugs
this PR was trying to fix. Like passing white on black to the
`UpdateDrawingBrushes` API, and expecting it to output the default `SGR
0` sequence, or passing an RGB color and expecting an indexed SGR
sequence.
In addition to that, I've added some VT renderer tests to make sure the
rendition attributes (bold, underline, etc) are correctly retained when
a default color update causes an `SGR 0` sequence to be generated (the
source of bug #3076). And I've extended the VT renderer color tests
(both 256-color and 16-color) to make sure we're covering all of the
different color types (default, RGB, and both forms of indexed colors).
I've also tried to manually verify that all of the test cases in the
linked bug reports (and their associated duplicates) are now fixed when
this PR is applied.
Closes#2661Closes#3076Closes#3717Closes#5384Closes#5864
This is only a partial fix for #293, but I suspect the remaining cases
are unfixable.
Essentially what this does is map the default legacy foreground and
background attributes (typically white on black) to the `IsDefault`
color type in the `TextColor` class. As a result, we can now initialize
the buffer for "legacy" shells (like PowerShell and cmd.exe) with
default colors, instead of white on black. This fixes the startup
rendering in conpty clients, which expect an initial default background
color. It also makes these colors update appropriately when the default
palette values change.
One complication in getting this to work, is that the console permits
users to change which color indices are designated as defaults, so we
can't assume they'll always be white on black. This means that the
legacy-to-`TextAttribute` conversion will need access to those default
values.
Unfortunately the defaults are stored in the conhost `Settings` class
(the `_wFillAttribute` field), which isn't easily accessible to all the
code that needs to construct a `TextAttribute` from a legacy value. The
`OutputCellIterator` is particularly problematic, because some iterator
types need to generate a new `TextAttribute` on every iteration.
So after trying a couple of different approaches, I decided that the
least worst option would be to add a pair of static properties for the
legacy defaults in the `TextAttribute` class itself, then refresh those
values from the `Settings` class whenever the defaults changed (this
only happens on startup, or when the conhost _Properties_ dialog is
edited).
And once the `TextAttribute` class had access to those defaults, it was
fairly easy to adapt the constructor to handle the conversion of default
values to the `IsDefault` color type. I could also then simplify the
`TextAttribute::GetLegacyAttributes` method which does the reverse
mapping, and which previously required the default values to be passed
in as a parameter
VALIDATION
I had to make one small change to the `TestRoundtripExhaustive` unit
test which assumed that all legacy attributes would convert to legacy
color types, which is no longer the case, but otherwise all the existing
tests passed as is. I added a new unit test verifying that the default
legacy attributes correctly mapped to default color types, and the
default color types were mapped back to the correct legacy attributes.
I've manually confirmed that this fixed the issue raised in #5952,
namely that the conhost screen is cleared with the correct default
colors, and also that it is correctly refreshed when changing the
palette from the properties dialog. And I've combined this PR with
#6506, and confirmed that the PowerShell and the cmd shell renderings in
Windows Terminal are at least improved, if not always perfect.
This is a prerequisite for PR #6506Closes#5952
This PR provides a faster algorithm for converting 8-bit and 24-bit
colors into the 4-bit legacy values that are required by the Win32
console APIs. It also fixes areas of the code that were incorrectly
using a simple 16-color conversion that didn't handle 8-bit and 24-bit
values.
The faster conversion algorithm should be an improvement for issues #783
and #3950.
One of the main points of this PR was to fix the
`ReadConsoleOutputAttribute` API, which was using a simplified legacy
color conversion (the original `TextAttribute:GetLegacyAttributes`
method), which could only handle values from the 16-color table. RGB
values, and colors from the 256-color table, would be mapped to
completely nonsensical values. This API has now been updated to use the
more correct `Settings::GenerateLegacyAttributes` method.
But there were also a couple of other places in the code that were using
`GetLegacyAttributes` when they really had no reason to be working with
legacy attributes at all. This could result in colors being downgraded
to 4-bit values (often badly, as explained above), when the code was
already perfectly capable of displaying the full 24-bits.
This included the fill colors in the IME composer (in `ConsoleImeInfo`),
and the construction of the highlighting colors in the color
search/selection handler (`Selection::_HandleColorSelection`). I also
got rid of some legacy attribute code in the `Popup` class, which was
originally intended to update colors below the popup when the settings
changed, but actually caused more problems than it solved.
The other major goal of this PR was to improve the performance of the
`GenerateLegacyAttributes` method, since the existing implementation
could be quite slow when dealing with RGB values.
The simple cases are handled much the same as they were before. For an
`IsDefault` color, we get the default index from the
`Settings::_wFillAttribute` field. For an `IsIndex16` color, the index
can just be returned as is.
For an `IsRgb` color, the RGB components are compressed down to 8 bits
(3 red, 3 green, 2 blue), simply by dropping the least significant bits.
This 8-bit value is then used to lookup a representative 16-color value
from a hard-coded table. An `IsIndex256` color is also converted with a
lookup table, just using the existing 8-bit index.
The RGB mapping table was calculated by taking each compressed 8-bit
color, and picking a entry from the _Campbell_ palette that best
approximated that color. This was done by looking at a range of 24-bit
colors that mapped to the 8-bit value, finding the best _Campbell_ match
for each of them (using a [CIEDE2000] color difference calculation), and
then the most common match became the index that the 8-bit value would
map to.
The 256-color table was just a simpler version of this process. For each
entry in the table, we take the default RGB palette value, and find it's
closest match in the _Campbell_ palette.
Because these tables are hard-coded, the results won't adjust to changes
in the palette. However, they should still produce reasonable results
for palettes that follow the standard ANSI color range. And since
they're only a very loose approximation of the colors anyway, the exact
value really isn't that important.
That said, I have tried to make sure that if you take an RGB value for a
particular index in a reasonable color scheme, then the legacy color
mapped from that value should ideally match the same index. This will
never be possible for all color schemes, but I have tweaked a few of the
table entries to improve the results for some of the common schemes.
One other point worth making regarding the hard-coded tables: even if we
wanted to take the active palette into account, that wouldn't actually
be possible over a conpty connection, because we can't easily know what
color scheme the client application is using. At least this way the
results in conhost are guaranteed to be the same as in the Windows
Terminal.
[CIEDE2000]: https://en.wikipedia.org/wiki/Color_difference#CIEDE2000
## Validation Steps Performed
This code still passes the `TextAttributeTests` that check the basic
`GetLegacyAttribute` behaviour and verify the all legacy attributes
roundtrip correctly. However, some of the values in the `RgbColorTests`
had to be updated, since we're now intentionally returning different
values as a result of the changes to the RGB conversion algorithm.
I haven't added additional unit tests, but I have done a lot of manual
testing to see how well the new algorithm works with a range of colors
and a variety of different color schemes. It's not perfect in every
situation, but I think it works well enough for the purpose it serves.
I've also confirmed that the issues reported in #5940 and #6247 are now
fixed by these changes.
Closes#5940Closes#6247
This PR introduces a new `ColorType` to allow us to distinguish between
`SGR` indexed colors from the 16 color table, the lower half of which
can be brightened, and the ISO/ITU indexed colors from the 256 color
table, which have a fixed brightness. Retaining the distinction between
these two types will enable us to forward the correct `SGR` sequences to
conpty when addressing issue #2661.
The other benefit of retaining the color index (which we didn't
previously do for ISO/ITU colors) is that it ensures that the colors are
updated correctly when the color scheme is changed.
## References
* This is another step towards fixing the conpty narrowing bugs in issue
#2661.
* This is technically a fix for issue #5384, but that won't be apparent
until #2661 is complete.
## PR Checklist
* [x] Closes#1223
* [x] CLA signed.
* [x] Tests added/passed
* [ ] Requires documentation to be updated
* [x] I've discussed this with core contributors already.
## Detailed Description of the Pull Request / Additional comments
The first part of this PR was the introduction of a new `ColorType` in
the `TextColor` class. Instead of just the one `IsIndex` type, there is
now an `IsIndex16` and an `IsIndex256`. `IsIndex16` covers the eight
original ANSI colors set with `SGR 3x` and `SGR 4x`, as well as the
brighter aixterm variants set with `SGR 9x` and `SGR 10x`. `IsIndex256`
covers the 256 ISO/ITU indexed colors set with `SGR 38;5` and `SGR
48;5`.
There are two reasons for this distinction. The first is that the ANSI
colors have the potential to be brightened by the `SGR 1` bold
attribute, while the ISO/ITO color do not. The second reason is that
when forwarding an attributes through conpty, we want to try and
preserve the original SGR sequence that generated each color (to the
extent that that is possible). By having the two separate types, we can
map the `IsIndex16` colors back to ANSI/aixterm values, and `IsIndex256`
to the ISO/ITU sequences.
In addition to the VT colors, we also have to deal with the legacy
colors set by the Windows console APIs, but we don't really need a
separate type for those. It seemed most appropriate to me to store them
as `IsIndex256` colors, since it doesn't make sense to have them
brightened by the `SGR 1` attribute (which is what would happen if they
were stored as `IsIndex16`). If a console app wanted a bright color it
would have selected one, so we shouldn't be messing with that choice.
The second part of the PR was the unification of the two color tables.
Originally we had a 16 color table for the legacy colors, and a separate
table for the 256 ISO/ITU colors. These have now been merged into one,
so color table lookups no longer need to decide which of the two tables
they should be referencing. I've also updated all the methods that took
a color table as a parameter to use a `basic_string_view` instead of
separate pointer and length variables, which I think makes them a lot
easier and safer to work with.
With this new architecture in place, I could now update the
`AdaptDispatch` SGR implementation to store the ISO/ITU indexed colors
as `IsIndex256` values, where before they were mapped to RGB values
(which prevented them reflecting any color scheme changes). I could also
update the `TerminalDispatch` implementation to differentiate between
the two index types, so that the `SGR 1` brightening would only be
applied to the ANSI colors.
I've also done a bit of code refactoring to try and minimise any direct
access to the color tables, getting rid of a lot of places that were
copying tables with `memmove` operations. I'm hoping this will make it
easier for us to update the code in the future if we want to reorder the
table entries (which is likely a requirement for unifying the
`AdaptDispatch` and `TerminalDispatch` implementations).
## Validation Steps Performed
For testing, I've just updated the existing unit tests to account for
the API changes. The `TextColorTests` required an extra parameter
specifying the index type when setting an index. And the `AdapterTest`
and `ScreenBufferTests` required the use of the new `SetIndexedXXX`
methods in order to be explicit about the index type, instead of relying
on the `TextAttribute` constructor and the old `SetForeground` and
`SetBackground` methods which didn't have a way to differentiate index
types.
I've manually tested the various console APIs
(`SetConsoleTextAttribute`, `ReadConsoleOutputAttribute`, and
`ReadConsoleOutput`), to make sure they are still setting and reading
the attributes as well as they used to. And I've tested the
`SetConsoleScreenBufferInfoEx` and `GetConsoleScreenBufferInfoEx` APIs
to make sure they can read and write the color table correctly. I've
also tested the color table in the properties dialog, made sure it was
saved and restored from the registry correctly, and similarly saved and
restored from a shortcut link.
Note that there are still a bunch of issues with the color table APIs,
but no new problems have been introduced by the changes in this PR, as
far as I could tell.
I've also done a bunch of manual tests of `OSC 4` to make sure it's
updating all the colors correctly (at least in conhost), and confirmed
that the test case in issue #1223 now works as expected.
This is an attempt to simplify the SGR (Select Graphic Rendition)
implementation in conhost, to cut down on the number of methods required
in the `ConGetSet` interface, and pave the way for future improvements
and bug fixes. It already fixes one bug that prevented SGR 0 from being
correctly applied when combined with meta attributes.
* This a first step towards fixing the conpty narrowing bugs in issue
#2661
* I'm hoping the simplification of `ConGetSet` will also help with
#3849.
* Some of the `TextAttribute` refactoring in this PR overlaps with
similar work in PR #1978.
## Detailed Description of the Pull Request / Additional comments
The main point of this PR was to simplify the
`AdaptDispatch::SetGraphicsRendition` implementation. So instead of
having it call a half a dozen methods in the `ConGetSet` API, depending
on what kinds of attributes needed to be set, there is now just one call
to get current attributes, and another call to set the new value. All
adjustments to the attributes are made in the `AdaptDispatch` class, in
a simple switch statement.
To help with this refactoring, I also made some change to the
`TextAttribute` class to make it easier to work with. This included
adding a set of methods for setting (and getting) the individual
attribute flags, instead of having the calling code being exposed to the
internal attribute structures and messing with bit manipulation. I've
tried to get rid of any methods that were directly setting legacy, meta,
and extended attributes.
Other than the fix to the `SGR 0` bug, the `AdaptDispatch` refactoring
mostly follows the behaviour of the original code. In particular, it
still maps the `SGR 38/48` indexed colors to RGB instead of retaining
the index, which is what we ultimately need it to do. Fixing that will
first require the color tables to be unified (issue #1223), which I'm
hoping to address in a followup PR.
But for now, mapping the indexed colors to RGB values required adding an
an additional `ConGetSet` API to lookup the color table entries. In the
future that won't be necessary, but the API will still be useful for
other color reporting operations that we may want to support. I've made
this API, and the existing setter, standardise on index values being in
the "Xterm" order, since that'll be essential for unifying the code with
the terminal adapter one day.
I should also point out one minor change to the `SGR 38/48` behavior,
which is that out-of-range RGB colors are now ignored rather than being
clamped, since that matches the way Xterm works.
## Validation Steps Performed
This refactoring has obviously required corresponding changes to the
unit tests, but most were just minor updates to use the new
`TextAttribute` methods without any real change in behavior. However,
the adapter tests did require significant changes to accommodate the new
`ConGetSet` API. The basic structure of the tests remain the same, but
the simpler API has meant fewer values needed to be checked in each test
case. I think they are all still covering the areas there were intended
to, though, and they are all still passing.
Other than getting the unit tests to work, I've also done a bunch of
manual testing of my own. I've made sure the color tests in Vttest all
still work as well as they used to. And I've confirmed that the test
case from issue #5341 is now working correctly.
Closes#5341
cmatrix is somewhat of a pathological case for our infrastructure: it
prints out a bunch of green and white characters and then updates them a
million times a second.
It also maintains a column of space between every green character. When
it prints this column, it prints it in "default" or "white". This ends
up making runs of text that look like this:
(def: G=green B=bright white W=white *=matrix char =space)
G W G W G W G W G W G W G W G W
G W G W G W G W G W G W G W G W
G W G W G W G W G W G W G W G W
G W G W G W G W G W G W G W G W
G W G W G W G W G W G W G W G W
G W G W G W G W G W G W G W G W
G W G W G W G W G W G W G W G W
G W G W G W G W G W G W G W G W
As characters trickle in:
G*W G*W G*W G*W G*W G*W G*W B*W
G*W G*W G*W G*W G*W G*W G*W G W
G*W G*W G*W B*W G*W G*W G*W G W
G*W B*W G*W G W G*W G*W G*W G*W
G*W G W G*W G W G*W B*W G*W G*W
B*W G W G*W G W G*W G W B*W G*W
G W G W G*W G W G*W G W G W B*W
G W G W B*W G W G*W G W G W G W
Every one of those color transitions causes us to break up the run of
text and start rendering it again. This impacts GDI, Direct2D *and*
ConPTY. In the example above, there are 120 runs.
The problem is, printing a space doesn't **use** the foreground color!
This commit introduces an optimization. When we're about to break a text
cluster because its attributes changed, we make sure that it's not just
filled with spaces and doesn't differ in any visually-meaningful way
(like underline or strikethrough, considering global invert state).
This lets us optimize both the rendering _and_ the PTY output to look
like this:
G* * * * * * * B*G
G* * * * * * *
G* * * B*G * * *
G* B*G * * * * *
G* * * B*G * *
B*G * * B*G *
G * * B*G
G B*G *
Text will be printed at best line-by-line and at worst only when the
visible properties of the screen actually change. In the example
above, there are only 21 runs.
This speeds up cmatrix remarkably.
Refs #1064
## Summary of the Pull Request
Operations that erase areas of the screen are typically meant to do so using the current color attributes, but with the rendition attributes reset (what we refer to as meta attributes). This also includes scroll operations that have to clear the area of the screen that has scrolled into view. The only exception is the _Erase Scrollback_ operation, which needs to reset the buffer with the default attributes. This PR updates all of these cases to apply the correct attributes when scrolling and erasing.
## PR Checklist
* [x] Closes#2553
* [x] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [x] Tests added/passed
* [ ] Requires documentation to be updated
* [ ] I've not really discussed this with core contributors. I'm ready to accept this work might be rejected in favor of a different grand plan.
## Detailed Description of the Pull Request / Additional comments
My initial plan was to use a special case legacy attribute value to indicate the "standard erase attribute" which could safely be passed through the legacy APIs. But this wouldn't cover the cases that required default attributes to be used. And then with the changes in PR #2668 and #2987, it became clear that our requirements could be better achieved with a couple of new private APIs that wouldn't have to depend on legacy attribute hacks at all.
To that end, I've added the `PrivateFillRegion` and `PrivateScrollRegion` APIs to the `ConGetSet` interface. These are just thin wrappers around the existing `SCREEN_INFORMATION::Write` method and the `ScrollRegion` function respectively, but with a simple boolean parameter to choose between filling with default attributes or the standard erase attributes (i.e the current colors but with meta attributes reset).
With those new APIs in place, I could then update most scroll operations to use `PrivateScrollRegion`, and most erase operations to use `PrivateFillRegion`.
The functions affected by scrolling included:
* `DoSrvPrivateReverseLineFeed` (the RI command)
* `DoSrvPrivateModifyLinesImpl` (the IL and DL commands)
* `AdaptDispatch::_InsertDeleteHelper` (the ICH and DCH commands)
* `AdaptDispatch::_ScrollMovement` (the SU and SD commands)
The functions affected by erasing included:
* `AdaptDispatch::_EraseSingleLineHelper` (the EL command, and most ED variants)
* `AdaptDispatch::EraseCharacters` (the ECH command)
While updating these erase methods, I noticed that both of them also required boundary fixes similar to those in PR #2505 (i.e. the horizontal extent of the erase operation should apply to the full width of the buffer, and not just the current viewport width), so I've addressed that at the same time.
In addition to the changes above, there were also a few special cases, the first being the line feed handling, which required updating in a number of places to use the correct erase attributes:
* `SCREEN_INFORMATION::InitializeCursorRowAttributes` - this is used to initialise the rows that pan into view when the viewport is moved down the buffer.
* `TextBuffer::IncrementCircularBuffer` - this occurs when we scroll passed the very end of the buffer, and a recycled row now needs to be reinitialised.
* `AdjustCursorPosition` - when within margin boundaries, this relies on a couple of direct calls to `ScrollRegion` which needed to be passed the correct fill attributes.
The second special case was the full screen erase sequence (`ESC 2 J`), which is handled separately from the other ED sequences. This required updating the `SCREEN_INFORMATION::VtEraseAll` method to use the standard erase attributes, and also required changes to the horizontal extent of the filled area, since it should have been clearing the full buffer width (the same issue as the other erase operations mentioned above).
Finally, there was the `AdaptDispatch::_EraseScrollback` method, which uses both scroll and fill operations, which could now be handled by the new `PrivateScrollRegion` and `PrivateFillRegion` APIs. But in this case we needed to fill with the default attributes rather than the standard erase attributes. And again this implementation needed some changes to make sure the full width of the active area was retained after the erase, similar to the horizontal boundary issues with the other erase operations.
Once all these changes were made, there were a few areas of the code that could then be simplified quite a bit. The `FillConsoleOutputCharacterW`, `FillConsoleOutputAttribute`, and `ScrollConsoleScreenBufferW` were no longer needed in the `ConGetSet` interface, so all of that code could now be removed. The `_EraseSingleLineDistanceHelper` and `_EraseAreaHelper` methods in the `AdaptDispatch` class were also no longer required and could be removed.
Then there were the hacks to handle legacy default colors in the `FillConsoleOutputAttributeImpl` and `ScrollConsoleScreenBufferWImpl` implementations. Since those hacks were only needed for VT operations, and the VT code no longer calls those methods, there was no longer a need to retain that behaviour (in fact there are probably some edge cases where that behaviour might have been considered a bug when reached via the public console APIs).
## Validation Steps Performed
For most of the scrolling operations there were already existing tests in place, and those could easily be extended to check that the meta attributes were correctly reset when filling the revealed lines of the scrolling region.
In the screen buffer tests, I made updates of that sort to the `ScrollOperations` method (handling SU, SD, IL, DL, and RI), the `InsertChars` and `DeleteChars` methods (ICH and DCH), and the `VtNewlinePastViewport` method (LF). I also added a new `VtNewlinePastEndOfBuffer` test to check the case where the line feed causes the viewport to pan past the end of the buffer.
The erase operations, however, were being covered by adapter tests, and those aren't really suited for this kind of functionality (the same sort of issue came up in PR #2505). As a result I've had to reimplement those tests as screen buffer tests.
Most of the erase operations are covered by the `EraseTests` method, except the for the scrollback erase which has a dedicated `EraseScrollbackTests` method. I've also had to replace the `HardReset` adapter test, but that was already mostly covered by the `HardResetBuffer` screen buffer test, which I've now extended slightly (it could do with some more checks, but I think that can wait for a future PR when we're fixing other RIS issues).
## Summary of the Pull Request
Adds support for Italics, Blinking, Invisible, CrossedOut text, THROUGH CONPTY. This does **NOT** add support for those styles to conhost or the terminal.
We will store these "Extended Text Attributes" in a `TextAttribute`. When we go to render a line, we'll see if the state has changed from our previous state, and if so, we'll appropriately toggle that state with VT. Boldness has been moved from a `bool` to a single bit in these flags.
Technically, now that these are stored in the buffer, we only need to make changes to the renderers to be able to support them. That's not being done as a part of this PR however.
## References
See also #2915 and #2916, which are some follow-up tasks from this fix. I thought them too risky for 20H1.
## PR Checklist
* [x] Closes#2554
* [x] I work here
* [x] Tests added/passed
* [n/a] Requires documentation to be updated
<hr>
* store text with extended attributes too
* Plumb attributes through all the renderers
* parse extended attrs, though we're not renderering them right
* Render these states correctly
* Add a very extensive test
* Cleanup for PR
* a block of PR feedback
* add 512 test cases
* Fix the build
* Fix @carlos-zamora's suggestions
* @miniksa's PR feedback
James Holderness
Mike Griese
Leonard Hecker
PankajBhojwani
Dan Thompson
Dustin L. Howett
Michael Niksa
Hermès BÉLUSCA - MAÏTO
