The Servo Browser Engine
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Emilio Cobos Álvarez 2e388e860d style: Align user-select behavior more with other UAs.
There's a few subtle behavior changes here, which I'll try to break down in the
commit message.

The biggest one is the EditableDescendantCount stuff going away. This
was added in bug 1181130, to prevent clicking on the non-editable div from
selecting the editable div inside. This is problematic for multiple reasons:

 * First, I don't think non-editable regions of an editable element should
   be user-select: all.

 * Second, it just doesn't work in Shadow DOM (the editable descendant count is
   not kept up-to-date when not in the uncomposed doc), so nested
   contenteditables behave differently inside vs. outside a Shadow Tree.

 * Third, I think it's user hostile to just entirely disable selection if you
   have a contenteditable descendant as a child of a user-select: all thing.

   WebKit behaves like this patch in the following test-case (though not Blink):

     https://crisal.io/tmp/user-select-all-contenteditable-descendant.html

   Edge doesn't seem to support user-select: all at all (no pun intended).

   But we don't allow to select anything at all which looks wrong.

 * Fourth, it's not tested at all (which explains how we broke it in Shadow DOM
   and not even notice...).

In any case I've verified that this doesn't regress the editor from that bug. If
this regresses anything we can fix it as outlined in the first bullet point
above, which should also make us more compatible with other UAs in that
test-case.

The other change is `all` not overriding everything else. So, something like:

  <div style="-webkit-user-select: all">All <div style="-webkit-user-select: none">None</div></div>

Totally ignores the -webkit-user-select: none declaration in Firefox before this
change. This doesn't match any other UA nor the spec, and this patch aligns us
with WebKit / Blink.

This in turn makes us not need -moz-text anymore, whose only purpose was to
avoid this.

This also fixes a variety of bugs uncovered by the previous changes, like the
SetIgnoreUserModify(false) call in editor being completely useless, since
presShell->SetCaretEnabled ended in nsCaret::SetVisible, which overrode it.

This in turn uncovered even more bugs, from bugs in the caret painting code,
like not checking -moz-user-modify on the right frame if you're the last frame
of a line, to even funnier bits where before this patch you show the caret but
can't write at all...

In any case, the new setup I came up with is that when you're editing (the
selection is focused on an editable node) moving the caret forces it to end up
in an editable node, thus jumping over non-editable ones.

This has the nice effect of not completely disabling selection of
-moz-user-select: all elements that have editable descendants (which was a very
ad-hoc hack for bug 1181130, and somewhat broken per the above), and also
not needing the -moz-user-select: all for non-editable bits in contenteditable.css
at all.

This also fixes issues with br-skipping like not being able to insert content in
the following test-case:

  <div contenteditable="true"><span contenteditable="false">xyz </span><br>editable</div>

If you start moving to the left from the second line, for example.

I think this yields way better behavior in all the relevant test-cases from bug
1181130 / bug 1109968 / bug 1132768, shouldn't cause any regression, and the
complexity is significantly reduced in some places.

There's still some other broken bits that this patch doesn't fix, but I'll file
follow-ups for those.

Differential Revision: https://phabricator.services.mozilla.com/D12687
2018-12-02 14:17:20 -05:00
.cargo new android port: update fakeld 2018-07-31 22:39:45 +08:00
components style: Align user-select behavior more with other UAs. 2018-12-02 14:17:20 -05:00
docs Replace http with https in docs 2018-11-06 11:39:09 +01:00
etc Fix logic error from “Don’t run warnings into errors when trying Nightly” 2018-12-02 11:23:33 +01:00
ports Auto merge of #22349 - paulrouget:androidlogs_update, r=jdm 2018-12-01 21:21:21 -05:00
python Automatically enable webvr for Android VR builds 2018-11-28 15:43:24 -08:00
resources Restructure package-specific preferences, add support for VR-only prefs 2018-11-28 15:38:19 -08:00
support Auto merge of #22322 - ferjm:windows.extra.backslash, r=jdm 2018-11-30 17:25:00 -05:00
tests Update web-platform-tests to revision de9a09ab7f605aed6a4b53ed96427412bab76463 2018-12-01 22:55:47 -05:00
.gitattributes Appease Github's Linguist 2015-06-11 00:16:42 -04:00
.gitignore Update manifest integration to reflect upstream API changes. 2018-11-23 15:48:02 -05:00
.hgignore Add .hgignore file 2017-02-03 18:42:52 -08:00
.mailmap Backed out changeset 3232d68da948 for testing Servo backout service 2017-06-23 20:47:52 +00:00
.taskcluster.yml Make Taskcluster tasks show up on Treeherder 2018-11-20 19:56:30 +01:00
.travis.yml Fix test-tidy self test 2018-11-07 09:37:55 +01:00
appveyor.yml Don't use mach wrappers for rustc/cargo smoketests on Windows. 2018-09-28 09:27:53 -04:00
Cargo.lock Auto merge of #22349 - paulrouget:androidlogs_update, r=jdm 2018-12-01 21:21:21 -05:00
Cargo.toml Support building for Magic Leap. 2018-10-29 08:49:41 -05:00
CLOBBER Add clobber mechanism 2017-05-08 16:19:56 +02:00
CONTRIBUTING.md Replace http with https in docs 2018-11-06 11:39:09 +01:00
dependencyci.yml Don't report smallbitvec as an error. 2017-10-16 11:38:34 -04:00
Info.plist remove bhtml 2018-02-11 08:02:39 +01:00
LICENSE Update MPL license to https (part 1) 2018-11-19 14:46:43 +01:00
mach Update MPL license to https (part 1) 2018-11-19 14:46:43 +01:00
mach.bat mach.bat: exit with an error code 2018-10-08 16:44:21 +02:00
PULL_REQUEST_TEMPLATE.md Fix pull request template 2018-04-29 16:18:13 +02:00
README.md Recommend in README the same Brewfile as used in CI 2018-11-22 17:46:49 +01:00
rust-toolchain Upgrade to rustc 1.31.0-nightly (8c4ad4e9e 2018-10-04) 2018-10-05 15:06:29 +02:00
rustfmt.toml Reorder imports 2018-11-06 22:35:07 +01:00
servo-tidy.toml Update syn and related dependencies 2018-11-30 17:48:41 +01:00
servobuild.example script: Optionally store backtraces when throwing DOM exceptions. 2018-10-01 16:04:56 +02:00

The Servo Parallel Browser Engine Project

Linux Build Status Windows Build Status Changelog #228

Servo is a prototype web browser engine written in the Rust language. It is currently developed on 64-bit macOS, 64-bit Linux, 64-bit Windows, and Android.

Servo welcomes contribution from everyone. See CONTRIBUTING.md and HACKING_QUICKSTART.md for help getting started.

Visit the Servo Project page for news and guides.

Setting up your environment

Rustup.rs

Building servo requires rustup, version 1.8.0 or more recent. If you have an older version, run rustup self update.

To install on Windows, download and run rustup-init.exe then follow the onscreen instructions.

To install on other systems, run:

curl https://sh.rustup.rs -sSf | sh

This will also download the current stable version of Rust, which Servo wont use. To skip that step, run instead:

curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain none

See also Other installation methods

Other dependencies

Please select your operating system:

macOS

On macOS (homebrew)
brew bundle install --file=etc/taskcluster/macos/Brewfile
pip install virtualenv
On macOS (MacPorts)
sudo port install python27 py27-virtualenv cmake yasm llvm
On macOS >= 10.11 (El Capitan), you also have to install OpenSSL
brew install openssl

export OPENSSL_INCLUDE_DIR="$(brew --prefix openssl)/include"
export OPENSSL_LIB_DIR="$(brew --prefix openssl)/lib"

./mach build ...

If you've already partially compiled servo but forgot to do this step, run ./mach clean, set the shell variables, and recompile.

On Debian-based Linuxes

Please run ./mach bootstrap.

If this doesn't work, file a bug, and, run the commands below:

sudo apt install git curl autoconf libx11-dev \
    libfreetype6-dev libgl1-mesa-dri libglib2.0-dev xorg-dev \
    gperf g++ build-essential cmake virtualenv python-pip \
    libssl1.0-dev libbz2-dev libosmesa6-dev libxmu6 libxmu-dev \
    libglu1-mesa-dev libgles2-mesa-dev libegl1-mesa-dev libdbus-1-dev \
    libharfbuzz-dev ccache clang \
    libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libgstreamer-plugins-bad1.0-dev autoconf2.13

If you using a version prior to Ubuntu 17.04 or Debian Sid, replace libssl1.0-dev with libssl-dev. Additionally, you'll need a local copy of GStreamer with a version later than 12.0. You can place it in support/linux/gstreamer/gstreamer, or run ./mach bootstrap-gstreamer to set it up.

If you are using Ubuntu 16.04 run export HARFBUZZ_SYS_NO_PKG_CONFIG=1 before building to avoid an error with harfbuzz.

If you are on Ubuntu 14.04 and encountered errors on installing these dependencies involving libcheese, see #6158 for a workaround. You may also need to install gcc 4.9, clang 4.0, and cmake 3.2:

gcc 4.9:
sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt-get update
sudo apt-get install gcc-4.9 g++-4.9
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.9 60 --slave /usr/bin/g++ g++ /usr/bin/g++-4.9

clang 4.0:

wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
sudo apt-add-repository "deb http://apt.llvm.org/trusty/ llvm-toolchain-trusty-4.0 main"
sudo apt-get update
sudo apt-get install -y clang-4.0

cmake 3.2:

sudo apt-get install software-properties-common
sudo add-apt-repository ppa:george-edison55/cmake-3.x
sudo apt-get update
sudo apt-get install cmake

If virtualenv does not exist, try python-virtualenv.

On Fedora

Please run ./mach bootstrap.

If this doesn't work, file a bug, and, run the commands below:

sudo dnf install curl libtool gcc-c++ libXi-devel \
    freetype-devel mesa-libGL-devel mesa-libEGL-devel glib2-devel libX11-devel libXrandr-devel gperf \
    fontconfig-devel cabextract ttmkfdir python2 python2-virtualenv python2-pip expat-devel \
    rpm-build openssl-devel cmake bzip2-devel libXcursor-devel libXmu-devel mesa-libOSMesa-devel \
    dbus-devel ncurses-devel harfbuzz-devel ccache mesa-libGLU-devel clang clang-libs gstreamer1-devel \
    gstreamer1-plugins-base-devel gstreamer1-plugins-bad-free-devel autoconf213

On CentOS

Please run ./mach bootstrap.

If this doesn't work, file a bug, and, run the commands below:

sudo yum install curl libtool gcc-c++ libXi-devel \
    freetype-devel mesa-libGL-devel mesa-libEGL-devel glib2-devel libX11-devel libXrandr-devel gperf \
    fontconfig-devel cabextract ttmkfdir python python-virtualenv python-pip expat-devel \
    rpm-build openssl-devel cmake3 bzip2-devel libXcursor-devel libXmu-devel mesa-libOSMesa-devel \
    dbus-devel ncurses-devel python34 harfbuzz-devel ccache clang clang-libs llvm-toolset-7

Build inside llvm-toolset and devtoolset:

scl enable devtoolset-7 llvm-toolset-7 bash

with the following environmental variables set:

export CMAKE=cmake3
export LIBCLANG_PATH=/opt/rh/llvm-toolset-7/root/usr/lib64

On openSUSE Linux

sudo zypper install libX11-devel libexpat-devel libbz2-devel Mesa-libEGL-devel Mesa-libGL-devel cabextract cmake \
    dbus-1-devel fontconfig-devel freetype-devel gcc-c++ git glib2-devel gperf \
    harfbuzz-devel libOSMesa-devel libXcursor-devel libXi-devel libXmu-devel libXrandr-devel libopenssl-devel \
    python-pip python-virtualenv rpm-build glu-devel ccache llvm-clang libclang

On Arch Linux

sudo pacman -S --needed base-devel git python2 python2-virtualenv python2-pip mesa cmake bzip2 libxmu glu \
    pkg-config ttf-fira-sans harfbuzz ccache clang autoconf2.13 gstreamer gstreamer-vaapi

On Gentoo Linux

sudo emerge net-misc/curl \
    media-libs/freetype media-libs/mesa dev-util/gperf \
    dev-python/virtualenv dev-python/pip dev-libs/openssl \
    media-libs/harfbuzz dev-util/ccache \
    x11-libs/libXmu media-libs/glu x11-base/xorg-server sys-devel/clang \
    media-libs/gstreamer media-libs/gst-plugins-bad media-libs/gst-plugins-base

with the following environment variable set:

export LIBCLANG_PATH="/usr/lib64/llvm/*/lib64"

On Windows (MSVC)

  1. Install Python for Windows (https://www.python.org/downloads/release/python-2714/). The Windows x86-64 MSI installer is fine. You should change the installation to install the "Add python.exe to Path" feature.

  2. Install virtualenv.

In a normal Windows Shell (cmd.exe or "Command Prompt" from the start menu), do:

pip install virtualenv

If this does not work, you may need to reboot for the changed PATH settings (by the python installer) to take effect.

  1. Install the most recent GStreamer development package following these instructions. You will also need to add C:\gstreamer\1.0\x86_64\bin to your LIB environment variable.

  2. Install Git for Windows (https://git-scm.com/download/win). DO allow it to add git.exe to the PATH (default settings for the installer are fine).

  3. Install Visual Studio Community 2017 (https://www.visualstudio.com/vs/community/). You MUST add "Visual C++" to the list of installed components. It is not on by default. Visual Studio 2017 MUST installed to the default location or mach.bat will not find it.

You may experience much faster builds on Windows by following these steps. (Related Rust issue: https://github.com/rust-lang/rust/issues/37543)

  1. Download the latest version of LLVM (https://releases.llvm.org/).
  2. Run the installer and choose to add LLVM to the system PATH.
  3. Add the following to your Cargo config (Found at %USERPROFILE%\.cargo\config). You may need to change the triple to match your environment.
[target.x86_64-pc-windows-msvc]
linker = "lld-link.exe"
Troubleshooting a Windows environment

If you encountered errors with the environment above, do the following for a workaround:

  1. Download and install Build Tools for Visual Studio 2017
  2. Install python2.7 x86-x64 and virtualenv
  3. Run mach.bat build -d.

If you have troubles with x64 type prompt as mach.bat set by default:

  1. You may need to choose and launch the type manually, such as x86_x64 Cross Tools Command Prompt for VS 2017 in the Windows menu.)
  2. cd to/the/path/servo
  3. python mach build -d

Cross-compilation for Android

Run ./mach bootstrap-android --build to get Android-specific tools. See wiki for details.

The Rust compiler

Servo's build system uses rustup.rs to automatically download a Rust compiler. This is a specific version of Rust Nightly determined by the rust-toolchain file.

Building

Servo is built with Cargo, the Rust package manager. We also use Mozilla's Mach tools to orchestrate the build and other tasks.

Normal build

To build Servo in development mode. This is useful for development, but the resulting binary is very slow.

git clone https://github.com/servo/servo
cd servo
./mach build --dev
./mach run tests/html/about-mozilla.html

Or on Windows MSVC, in a normal Command Prompt (cmd.exe):

git clone https://github.com/servo/servo
cd servo
mach.bat build --dev

For benchmarking, performance testing, or real-world use, add the --release flag to create an optimized build:

./mach build --release
./mach run --release tests/html/about-mozilla.html

Note: mach build will build both servo and libsimpleservo. To make compilation a bit faster, it's possible to only compile the servo binary: ./mach build --dev -p servo.

Checking for build errors, without building

If youre making changes to one crate that cause build errors in another crate, consider this instead of a full build:

./mach check

It will run cargo check, which runs the analysis phase of the compiler (and so shows build errors if any) but skips the code generation phase. This can be a lot faster than a full build, though of course it doesnt produce a binary you can run.

Building for Android target

For ARM (armv7-linux-androideabi, most phones):

./mach build --release --android
./mach package --release --android

For x86 (typically for the emulator):

./mach build --release --target i686-linux-android
./mach package --release --target i686-linux-android

Running

Run Servo with the command:

./servo [url] [arguments] # if you run with nightly build
./mach run [url] [arguments] # if you run with mach

# For example
./mach run https://www.google.com

Commandline Arguments

  • -p INTERVAL turns on the profiler and dumps info to the console every INTERVAL seconds
  • -s SIZE sets the tile size for painting; defaults to 512
  • -z disables all graphical output; useful for running JS / layout tests
  • -Z help displays useful output to debug servo

Keyboard Shortcuts

  • Ctrl+L opens URL prompt (Cmd+L on Mac)
  • Ctrl+R reloads current page (Cmd+R on Mac)
  • Ctrl+- zooms out (Cmd+- on Mac)
  • Ctrl+= zooms in (Cmd+= on Mac)
  • Alt+left arrow goes backwards in the history (Cmd+left arrow on Mac)
  • Alt+right arrow goes forwards in the history (Cmd+right arrow on Mac)
  • Esc or Ctrl+Q exits Servo (Cmd+Q on Mac)

Developing

There are lots of mach commands you can use. You can list them with ./mach --help.

The generated documentation can be found on https://doc.servo.org/servo/index.html