GCov Coverage Viewer

A VS Code extension that renders .c.gcov files as a visual coverage report instead of raw text.

Features

• Line coverage — covered lines highlighted green, uncovered red, non-executable lines unstyled
• Execution counts — how many times each line was executed, shown next to the line number
• Branch coverage — colored dots on each branch line showing which branches were taken
• MC/DC coverage — per-condition breakdown on hover showing which outcomes (true/false) were tested and which were not
• Coverage summary bar — line, branch and MC/DC percentages shown at the top of the file
• Hover tooltips — branch and MC/DC details on hover, styled like VS Code's native hover widget
• Theme aware — uses VS Code CSS variables, works with any light or dark theme

Usage

Open any .gcov file generated by gcov -b -c -g and the viewer activates automatically.

To generate a .gcov file with full branch and MC/DC data:

gcov -b -c -g --object-directory <build_dir> <source_file.c>

Requirements

• GCC with gcov support (arm-none-eabi-gcov or standard gcov)
• Compile with -fprofile-arcs -ftest-coverage --coverage
• Run gcov with -b -c -g flags to get branch and MC/DC data