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Visual Studio Code (VS Code) is a free, open source, lightweight and powerful code editor for Windows, macOS and Linux, based on Electron/Chromium. It has built-in support for JavaScript, TypeScript and Node.js and a rich extension ecosystem that adds intellisense, debugging, syntax highlighting etc. For many languages like C++, Python, Go, Java, it works without too much setup.
It is NOT a full-fledged IDE like Visual Studio. The two are completely separate products. The only commonality with Visual Studio is that both are from Microsoft.
Here's what works well:
- Editing code works well especially when you get used to the keyboard shortcuts. VS Code is very responsive and can handle even big code bases like Chromium.
- Git integration is a blast. Built-in side-by-side view, local commit and even extensions for history and blame view.
- Debugging works
well, even though startup times can be fairly high (~40 seconds with
gdb on Linux, much lower on Windows). You can step through code, inspect
variables, view call stacks for multiple threads etc.
- For more information on debugging Python code, see here.
- Command Palette makes opening files and searching solution really easy.
- Building works well. Build tools are easy to integrate. Warnings and errors are displayed on a separate page and you can click to jump to the corresponding line of code.
- VS Code Remote, which allows you to edit remotely-hosted code, and even run computationally expensive plugins like vscode-clangd on the remote server. Great for working from home. See the Remote section for more details.
[TOC]
Please keep this doc up-to-date. VS Code is still in active development and subject to changes. This doc is checked into the Chromium git repo, so if you make changes, read the documentation guidelines and submit a change list.
All file paths and commands have been tested on Linux and macOS. Windows might require a slightly different setup. Please update this page accordingly.
*** promo Googlers: See go/vscode/install.
Follow the steps on Setting up Visual Studio Code.
To run it on Linux or on macOS, just navigate to Chromium's src
folder and
type code .
in a terminal. The argument to code
is the base directory of the
workspace. VS Code does not require project or solution files. However, it does
store workspace settings in a .vscode
folder in your base directory (i.e. your
project root folder).
If you installed Code Insiders, the binary name is code-insiders
instead.
If you only have the depot_tools
Git installed on your machine, even though it
is in your PATH, VS Code will ignore it as it seems to be looking for git.exe
.
You will have to add the following to your settings in order for the Git
integration to work:
{
"git.path": "C:\\src\\depot_tools\\git.bat"
// more settings here...
}
Tip: you can jump to the settings JSON file by using Ctrl+Shift+P
and using
the "Preferences: Open User Settings (JSON)" verb (for whatever reason, setting
git.path
as a folder setting does not appear to work).
Up to now, you have a basic version of VS Code without much language support.
Next, we will install some useful extensions. Jump to the extensions window
(Ctrl+Shift+X
, or Cmd+Shift+X
in macOS) and install the extensions, or run
the following commands.
You will most likely use the following extensions every day:
$ echo "ms-vscode.cpptools llvm-vs-code-extensions.vscode-clangd ms-python.python bbenoist.togglehs peterj.proto Google.vscode-mojom msedge-dev.gnls stkb.rewrap ms-vscode-remote.remote-ssh eamodio.gitlens" | xargs -n 1 code --force --install-extension
- C/C++ -
Code formatting, debugging, Intellisense. Enables the use of clang-format
(via the
C_Cpp.clang_format_path
setting) and format-on-save (via theeditor.formatOnSave
setting). - vscode-clangd -
Enables VS Code to compile Chromium, provide Chromium XRefs to support
functions like jumping to definition, and provide smarter autocompletion
than C/C++ extension's IntelliSense, but they also conflicts with each
other. To resolve the conflict, add the following to
settings.json
:"C_Cpp.intelliSenseEngine": "Disabled"
. See clangd.md for setup instructions. - Python -
Linting, intellisense, code formatting, refactoring, debugging, snippets.
- If you want type checking, add:
"python.analysis.typeCheckingMode": "basic",
to yoursettings.json
file (you can also find it in the settings UI).
- If you want type checking, add:
- Toggle Header/Source -
Toggles between .cc and .h with
F4
. The C/C++ extension supports this as well throughAlt+O
but sometimes chooses the wrong file when there are multiple files in the workspace that have the same name. - Protobuf support - Syntax highlighting for .proto files.
- Mojom IDL support - Syntax highlighting and a language server for .mojom files.
- GN - Code IntelliSense for the GN build system.
- Rewrap -
Wrap lines at 80 characters with
Alt+Q
. - Remote - Remotely connect to your workstation through SSH using your laptop. See the Remote section for more information about how to set this up.
- GitLens - Git supercharged. A Powerful, feature rich, and highly customizable git extension.
The following extensions might be useful for you as well:
$ echo "wmaurer.change-case shd101wyy.markdown-preview-enhanced Gruntfuggly.todo-tree alefragnani.Bookmarks spmeesseman.vscode-taskexplorer streetsidesoftware.code-spell-checker george-alisson.html-preview-vscode anseki.vscode-color" | xargs -n 1 code --force --install-extension
- chromium-codesearch - macOS and Linux only: adds ability to open the current line in Chromium Code Search. All other functionality is deprecated, so currently only of limited usefulness.
- change-case - Quickly change the case of the current selection or current word.
- Markdown Preview Enhanced -
Preview markdown side-by-side with automatic scroll sync and many other
features with
Ctrl+k v
. This document was written with this extension! - Todo Tree - Displays comment tags like TODO/FIXME in a tree view in a dedicated sidebar.
- Bookmarks - Supports easy mark/unmark positions in the codebase and displays them in a dedicated sidebar. Very useful for a large codebase like Chromium.
- Task Explorer - Displays supported tasks, e.g. vscode tasks, shell scripts and others, organized into a treeview in sidebar.
- Code Spell Checker - A basic spell checker that works well with camelCase code. It helps catch common spelling errors.
- HTML Preview -
Previews HTML files while editing with
Ctrl+k v
. - Color Picker - Visualizes color codes inline and provides color picker GUI to generates new color codes.
Also be sure to take a look at the VS Code marketplace to check out other useful extensions.
Press Ctrl+Shift+P (Cmd+Shift+P
in macOS), color, Enter
to pick a color
scheme for the editor. There are also tons of color schemes available for
download on the
marketplace.
Ctrl+P
opens a search box to find and open a file.F1
orCtrl+Shift+P
opens a search box to find a command (e.g. Tasks: Run Task). Note: if you want to run one of the Predefined tasks in tasks.json, it is faster to just useCtrl+P
> "task ".Ctrl+K, Ctrl+S
opens the key bindings editor.Ctrl+`
toggles the built-in terminal.Ctrl+Shift+M
toggles the problems view (linter warnings, compile errors and warnings). You'll switch a lot between terminal and problem view during compilation.Alt+O
switches between the source/header file.Ctrl+G
jumps to a line.F12
jumps to the definition of the symbol at the cursor (also available on right-click context menu).Shift+F12
orF1, CodeSearchReferences, Return
shows all references of the symbol at the cursor.F1, CodeSearchOpen, Return
opens the current file in Code Search.Ctrl+D
selects the word at the cursor. Pressing it multiple times multi-selects the next occurrences, so typing in one types in all of them, andCtrl+U
deselects the last occurrence.Ctrl+K, Z
enters Zen Mode, a fullscreen editing mode with nothing but the current editor visible.Ctrl+X
without anything selected cuts the current line.Ctrl+V
pastes the line.
*** aside Note: See also Key Bindings for Visual Studio Code .
Follow these steps to get full IDE support (outline, autocompletion, jump to
definition including automatic decompilation of prebuilts, real-time reporting
of compile errors/warnings, Javadocs, etc.) when editing .java
files in
Chromium:
- Add the following to your VS Code workspace
settings.json
:"java.import.gradle.enabled": false
"java.import.maven.enabled": false
This will prevent the language server from attempting to build all Gradle and Maven projects that can be found anywhere in the Chromium source tree, which typically results in hilarity."java.jdt.ls.java.home": "<< ABSOLUTE PATH TO YOUR WORKING COPY OF CHROMIUM >>/src/third_party/jdk/current"
This one is optional but reduces the likelihood of problems by making sure the language server uses the same JDK as the Chromium build system (as opposed to some random JDK from your host system).
- Install the Language Support for Java™ by Red Hat extension. You do not need any other extension.
- In the VS Code explorer (left-hand pane) right-click on a folder (any folder) and click Add Folder to Java Source Path. This is just one way to force the extension to generate an internal build project for the language server. The specific folder doesn't matter because the source path configuration will be overwritten in step 6.
- Wait for the Successfully added '...' to the project src_...'s source path pop-up notification to appear. Note that this can take some time (1-2 minutes), during which VS Code seems to be idle.
- Build your code in the usual way (i.e. using gn and ninja commands). This will produce build config files that are necessary for the next step. It will also make autogenerated code visible to the language server.
- Generate the
.classpath
file for the internal build project by runningbuild/android/generate_vscode_classpath.py
with the appropriate arguments from the root of your VS Code workspace folder. For example, if your VS Code workspace is rooted insrc
, your build output directory isout/Debug-x86
and your build target is//components/cronet/android:cronet_javatests
, run:build/android/generate_vscode_classpath.py --output-dir out/Debug-x86 --build-config gen/components/cronet/android/cronet_javatests.build_config.json > ~/.vscode*/data/User/workspaceStorage/*/redhat.java/jdt_ws/.metadata/.plugins/org.eclipse.core.resources/.projects/src_*/.classpath
- Reload your VS Code window.
- Open a Java source file then wait a couple of minutes for the language server to build the project.
- Done! You should now have full Java language support for any
.java
file that is included in the build.
*** note
Warning: do not attempt to change the extension's source path settings, as
that risks overwriting the generated .classpath
file.
- Errors related to
GEN_JNI
are caused by the language server (rightfully) getting confused about multiple definitions of the autogeneratedGEN_JNI
class. This is a known quirk of the JNI generator.
Java code in Chromium is formatted using clang-format.
To get VS Code to use clang-format to format Java files, install the
Clang-Format extension
and set it as the default formatter for Java in your workspace settings.json
:
"[java]": {
"editor.defaultFormatter": "xaver.clang-format"
}
To avoid potential formatting differences due to clang-format version skew, it
makes sense to configure the extension to run clang-format in the same way
git cl format
would. You can do this by adding the following to your
workspace settings.json
:
"clang-format.executable": "<< PATH TO YOUR CHROMIUM WORKING COPY >>/src/buildtools/linux64/clang-format"
VS Code is configured via JSON files. This paragraph contains JSON configuration files that are useful for Chromium development, in particular. See VS Code documentation for an introduction to VS Code customization.
Open the file //tools/vscode/settings.json, and check out the default settings there. Feel free to commit added or removed settings to enable better team development, or change settings locally to suit personal preference.
To use these settings wholesale, enter the following commands into your terminal
while at the src/
directory:
$ mkdir .vscode/
$ cp tools/vscode/settings.json .vscode
Note: these settings assume that the workspace folder (the root folder displayed
in the Explorer tab) is Chromium's src/
directory. If this is not the case,
replace any references to ${workspaceFolder} with the path to your src/
.
Next, we'll tell VS Code how to compile our code, run tests, and to read warnings and errors from the build output. Open the file //tools/vscode/tasks.json. This will provide tasks to do basic things. You might have to adjust the commands to your situation and needs. To use these settings wholesale, enter the following command into your terminal:
$ cp tools/vscode/tasks.json .vscode
Before running most of the tasks, you'll need to set the chromeOutputDir
value
in your .vscode/tasks.json
file.
Now you can run tasks by using Ctrl+P
(Cmd+Shift+P
in macOS) and typing
"task " and then a number of your choice. If you select one of the build tasks,
the build output will display in the terminal pane. Jump through build problems
quickly using F8 / Shift-F8. See task names for more info on
running tasks.
If you have intellisense enabled but do not have include paths set up correctly, jumping through problems will also try to navigate through all the include files it cannot locate and add a lot of noise. You can fix your include path or simply set intellisense to "tag parser" mode by doing the following:
- Open Preferences (
Ctrl+Shift+P
> "Preferences: Open User Settings"). - Type "intellisense engine" in the settings search box.
- Select "Tag Parser" as the provider.
Note: on a Chromebook, use 🔍+<8th button in the top row that's not ESC>. In most cases, this is the top row button that is the closest to be directly above the 8 key.
Launch commands are the equivalent of F5
in Visual Studio: They launch some
program or a debugger. Optionally, they can run some task defined in
tasks.json
. Launch commands can be run from the debug view (Ctrl+Shift+D
).
Open the file at //tools/vscode/launch.json and
adjust the example launch commands to your situation and needs (e.g., the value
of "type" needs adjustment for Windows). To use these settings wholesale, enter
the following command into your terminal:
$ cp tools/vscode/launch.json .vscode
To edit key bindings, press Ctrl+K, Ctrl+S
. You'll see the defaults on the
left and your overrides on the right stored in the file keybindings.json
. To
change a key binding, copy the corresponding key binding to the right. It's
fairly self-explanatory.
You can bind any command to a key, even commands specified by extensions like
CodeSearchOpen
. For instance, to bind CodeSearchOpen
to F2
to , simply add
{ "key": "F2", "command": "cs.open" },
.
Note that the command title CodeSearchOpen
won't work. You have to get the
actual command name from the package.json
file
of the extension.
If you are used to other editors, you can also install your favorite keymap.
For instance, to install eclipse keymaps, install the
vscode-eclipse-keybindings
extension. More keymaps can be found
in the marketplace.
Some key bindings that are likely to be useful for you are available at //tools/vscode/keybindings.json. Please take a look and adjust them to your situation and needs. To use these settings wholesale, enter the following command into your terminal:
$ cp tools/vscode/keybindings.json .vscode
*** promo Googlers: See go/vscode-remote.
VS Code now has a Remote framework that allows you to use VS Code on your laptop while your code is hosted elsewhere. This really shines when used in conjunction with the vscode-clangd plugin, which allows clangd to run remotely as well.
To get this to run, install the Remote pack extension, and then make sure your ssh config file has your remote connection:
~/.ssh/config
:
Host my-connection
HostName my-remote-host.corp.company.com
VS Code will then list this connection in the 'Remote Explorer' section on the left. To launch VS Code with this connection, click on the '+window' icon next to the listed hostname. It has you choose a folder - use the 'src' folder root. This will open a new VS Code window in 'Remote' mode. Now you can install extensions specifically for your remote connection, like vscode-clangd, etc.
For Googlers, here are Google-specific instructions for setting up remote development on chromebooks without using Crostini.
VS Code remote tools requires 'sshd' which isn't installed on Windows by default.
For Googlers, sshd should already be installed on your workstation, and VS Code should work remotely if you followed the setup instructions at go/building-chrome-win. If you are still having problems, please refer to go/vscode-remote#windows.
Non-Googlers may follow Microsoft's instructions for installing the OpenSSH server. VS Code should work remotely after following this step.
There are some useful snippets provided in //tools/vscode/cpp.json.
You can either install them in your user profile (path may vary depending on the platform):
$ mkdir -p ~/.config/Code/User/snippets
$ cp tools/vscode/cpp.json ~/.config/Code/User/snippets
Or install them as project snippets:
$ cp tools/vscode/cpp.json .vscode/cpp.code-snippets
Automatically generated code is put into a subfolder of out/
, which means that
these files are ignored by VS Code (see files.exclude above) and cannot be
opened e.g. from quick-open (Ctrl+P
). As of version 1.21, VS Code does not
support negated glob commands, but you can define a set of exclude pattern to
include only out/Debug/gen
:
"files.exclude": {
// Ignore build output folders. Except out/Debug/gen/
"out/[^D]*/": true,
"out/Debug/[^g]*": true,
"out/Debug/g[^e]*": true,
"out_*/**": true,
},
Once it does, you can use
"!out/Debug/gen/**": true
in files.exclude instead of the symlink.
Add [core] editor = "code --wait"
to your ~/.gitconfig
file in order to use
VS Code as editor for git commit messages etc. Note that the editor starts up
significantly slower than nano or vim. To use VS Code as merge tool, add
[merge] tool = code
.
Note that we named the tasks 1-build_chrome_debug
, 2-build_chrome_release
etc. This allows you to quickly execute tasks by pressing their number:
Press Ctrl+P
and enter task <n>
, where <n>
is the number of the task. You
can also create a keyboard shortcut for running a task. File > Preferences > Keyboard Shortcuts
and add { "key": "ctrl+r", "command": "workbench.action.tasks.runTask", "when": "!inDebugMode" }
. Then it's
sufficient to press Ctrl+R
and enter <n>
.
You might want to disable git status autorefresh to save battery.
"git.autorefresh": false,
If you frequently work in multiple Git repositories that are part of the Chromium repository, you might find that the built-in tooling does not work as expected for files that exist below folders that are part of a .gitignore
file checked in to Chromium.
To work around this, you can add the directories you edit as separate folders
entries in your workspace configuration, and ensure that the directories that are ignored in Chromium are listed before the Chromium src
path.
To edit this, go to Settings
-> Select the Workspace
tab, and choose to open as JSON (button in the top right), and configure folders
like this (change paths to match your local setup and usage):
{
"folders": [
{
"path": "chromium/src/third_party/perfetto"
},
{
"path": "chromium/src"
}
]
}
Chromium recently changed
the file path to be relative to the output dir. Check
gn args out/$dir --list
if strip_absolute_paths_from_debug_symbols
is true (which is the default),
set cwd
to the output dir. otherwise, set cwd
to ${workspaceFolder}
.
More tips and tricks can be found here.