Narcoleptic Pasta Manufacturer


    1.0.0 • Public • Published

    Theia - Cpp Extension

    This extension uses Clangd to provide LSP features.

    To install Clangd on Ubuntu 18.04:

    $ wget -O - | sudo apt-key add -
    $ echo "deb llvm-toolchain-bionic main" | sudo tee /etc/apt/sources.list.d/llvm.list
    $ sudo apt-get update && sudo apt-get install -y clangd

    See here for detailed installation instructions.

    Getting accurate diagnostics

    To get accurate diagnostics, it helps to:

    1. Have the build system of the C/C++ project generate a compile_commands.json file.
    2. Point Clangd to the build directory containing said compile_commands.json.

    Step #2 can be done using the cpp.buildConfigurations preference. In your home or your project .theia/settings.json, define one or more build configurations:

        "cpp.buildConfigurations": [{
            "name": "Release",
            "directory": "/path/to/my/release/build"
            "name": "Debug",
            "directory": "/path/to/my/debug/build"

    You can then select an active configuration using the C/C++: Change Build Configuration command from the command palette.

    Setting clangd executable path and arguments

    The path of the clangd executable to use can be specified by either:

    • Setting the CPP_CLANGD_COMMAND environment variable

    • Setting the cpp.clangdExecutable preference in your home or your project .theia/settings.json:

            "cpp.clangdExecutable": "/path/to/my/clangd/executable"
    • Adding clangd to system path. Default value of executable path is set to clangd

    Similarly, the command-line arguments passed to clangd can be specified by either:

    • Setting the CPP_CLANGD_ARGS environment variable

    • Setting the cpp.clangdArgs preference in your home or your project .theia/settings.json:

            "cpp.clangdArgs": "list of clangd arguments"

    Getting cross-file references to work

    You may notice that by default, cross-references across source file boundaries don't work. For example, doing a "Go To Definition" on a function defined in a different source file (different .c or .cpp) doesn't work, instead it sends you to the declaration of the function, typically in a header file.

    To get this working, you need to enable clangd's global index using the --background-index command-line argument.

            "cpp.clangdArgs": "--background-index"

    Using the clang-tidy linter

    Note: This functionality is available when using clangd 9 and later.

    You can set the preference 'cpp.clangTidy' to enable the clang-tidy linter included in clangd. When the preference is enabled, there are two ways to choose which of its built-in checks clang-tidy will use:

    • using the preferences: 'cpp.clangTidyChecks'
    • using the file '.clang-tidy' . This file is located in the same folder of the files or a parent folder.

    Note: When the preference setting for "cpp.clangTidyChecks" is set, the configs will be merged with the configuration found in the ".clang-tidy" file. If you want to drop the configs from ".clang-tidy", you'd need to disable it in "cpp.clangTidyChecks" with "cpp.clangTidyChecks": "-*".

    The syntax used to fill the checks can be found at

    clang-tidy has its own checks and can also run Clang static analyzer checks. Each check has a name (see link above for full list). Clang-tidy takes as input the checks that should run, in the form of a comma-separated list of positive and negative (prefixed with -) globs. Positive globs add subsets of checks, negative globs remove them.

    There are two ways to configure clang-tidy's checks: through a Theia preference or using a .clang-tidy config file. Here are examples for both:"

    - for the preferences: "cpp.clangTidyChecks": "*,-readability-*"
        - Meaning: enables all list-checks and disable all readability-* checks
    - for the .clang-tidy file: Checks: "-*,readability-*"
        - Meaning: disable all list-checks and enable all readability-* checks

    Running clang-tidy as a task

    To be able to run clang-tidy as a task, you need to install the program.

        sudo apt-get install clang-tidy
    Note: not all operating system are currently supported with this linter yet.
    The clang-tidy task will read the "checks" and other configuration fields from the ".clang-tidy" file located in the closest parent directory of the source file.
    P.S. You do not need to provide a value for each field.
    Those configurations fields can be:
    You can run the following command to have an idea of the fields found in file ".clang-tidy"
        clang-tidy -dump-config

    In .theia/tasks.json, add the following:

            "label": "[Task] clang-tidy",
            "type": "shell",
            "cwd": "${workspaceFolder}",
            "command": "clang-tidy",
            "args": [
            "options": {},
            "problemMatcher": [

    If you want a description for each task field, see theia/packages/task/src/browser/task-schema-updater.ts

    When there is no compilation database, clang-tidy could run but you may need to be more specific which files to select. One way is to replace the "args" from the "*" to
    "**/*.cpp" to only parse files with the "cpp" extension or
    "**/*.c" to parse the "c" files extension.



    npm i @theia/cpp

    DownloadsWeekly Downloads





    EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0

    Unpacked Size

    353 kB

    Total Files


    Last publish


    • marc.dumais
    • paul-marechal
    • bhufmann
    • vince-fugnitto
    • eclipsetheia