VSCode C++ Development Tools

A VSCode C++ development environment for Linux, richly populated with quality-oriented tools.

Motivation

VSCode users know that the application is highly expandable and flexible. They also know that discovering all the tools and techniques to configure VSCode is not easy. This repository presents a highly enriched VSCode environment for quality-oriented C++ development on Linux.

A C++ statistics accumulator class helps to showcase the environment's features. The class is similar to Boost's statistics accumulator, without the Boost dependency. The code is not the point of this repository. It serves to demonstrate the many additions required to turn VSCode in to a rich C++ IDE. Those many additions are the point of this repository. It might be used as a template for new VSCode C++ projects.

Developers using other IDEs, or even the command-line, might be interested in pieces from this project. For example, the custom build tasks for mutation testing and code sanitizers are powered by scripts easily transferred to other C++ development environments.

Overview

The developmment enviroonment is provided via two directories:

• .devcontainer

  A VSCode containerized development installlation based on Ubuntu. The developer works in the environment under their own account.

• .vscode

  VSCode settings, CMake variants, and custom tasks for C++ development.

The directories complement each other. The .vscode files provide settings for the .devcontainer tools.

The resulting VSCode session has many integrated tools available from the IDE's GUI:

• CMake tools with configuration pre-sets and build-target selection
• Auto-format on save (C++ and CMake files)
• Inline linter hints and git blame
• Test explorer and code coverage annotation
• Mutation testing
• Valgrind reports and code sanitizer reports

Read on below for detailed instructions in using the environment.

Use The Environment

These instructions assume you are working on Linux with VSCode, git, and docker installed. They also assume you have a GitHub account with a registered SSH key so you can clone this repository and open it in VSCode.

git clone git@github.com:ian-fisher-developer/vscode-cpp-dev-tools.git

cd vscode-cpp-dev-tools

code .

VSCode recognizes the .devcontainer directory and offers to re-open the project in the container. Or, click on Open a Remote Window (at the very left of the status bar) and choose Reopen in Container. Note that, for the first time only, it may take quite a while for VSCode to create the docker images.

When the DevContainer session is ready, follow these steps to exercise the environment's C++ development features.

• Configure the build

  The CMake Tools extension has a build-kit selector in the VSCode status bar. Choose GCC 11.4.0. The extension runs the CMake configure step to the build/build-vscode-cmake-tools directory.

• Build all and use the test explorer

  Choose the all build target (in the status bar selector) and build it to create the library, the unit-test program, and the example programs. Open the test explorer side pane to view and run the unit tests.

  The test explorer has controls to run all the tests or a single test. Or, set Start Continuous Run (at the top of the test explorer) to automatically run the tests when they are rebuilt. Note that in the screen-shot above, the test explorer is moved to VSCode's secondary side bar, on the right.

• Try the code editor

  Open src/lib/StatisticsAccumulator.cpp from the file explorer.

  The code editor has git blame for the current line. Mouse-over the brief inline description for a more detailed popup.

  Note the "squiggle" suggestions from the linter, clang-tidy. Mouse-over the deliberate misnaming of variable 'dVal' for more information and a "fixit" for this violation of the project's code naming conventions.

  The clangd extension from the LLVM project provides a full C++ code model, enabling many code editing helpers such as code completion options. Note that VSCode tends to install GitHub CoPilot by default. The AI's slop suggestions get in the way. Turn off GitHub CoPilot to return to accurate information from the code model.

  Ctrl-S auto-formats C++ and CMake files according to the project standards.

• Examine code coverage

  Switch from all to the statistics_coverage_report target and build it.

  Turn on the Coverage Gutters extension's Watch function (in the status bar) to add coverage annotation to the C++ code editor in the form of colored bars by the line numbers.

  Select Coverage Gutters: Preview Coverage Report from the editor's context menu to browse the HTML report.

• Test the tests

  A custom build task provides mutation testing for the project, helping find gaps in the tests, even when code coverage is all green. Select Run Build Task from VSCode's Terminal menu to create either a full mutation testing report, or an analysis for only the branch diffs.

• Look for memory leaks

  A custom build task runs the unit-test program under valgrind and logs the results to a valgrind report.

• Use the compiler's code sanitizers

  Two custom build tasks generate reports from the compiler's address sanitizer and undefined-behavior sanitizer. Each task builds the project's code with the corresponding sanitizer flag, then runs the unit-test program. The instrumented code writes to a log file if it finds any issues.