FEAT: Full Code Coverage & Workflow Integration

[bewithgaurav]

Work Item / Issue Reference

AB#38622

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Summary

This pull request introduces significant improvements to the PR validation pipeline by adding unified code coverage reporting for both Python and C++ code, enhancing the build process for coverage instrumentation, and optimizing the PR size label automation. The main changes are grouped below:

Pipeline Enhancements:

• Added a new CodeCoverageReport job to eng/pipelines/pr-validation-pipeline.yml that builds dependencies, runs tests, generates unified coverage reports (Python + C++), and publishes results in both HTML and Cobertura XML formats for Azure DevOps. This includes setup for SQL Server, Python dependencies, and C++ coverage instrumentation.
• Commented out the old code coverage publishing task in the pipeline to avoid duplicate or incomplete reporting, as the new job supersedes it.

Build and Coverage Tooling:

• Added a new script generate_codecov.sh to automate installation of coverage tools, run tests, collect and merge Python/C++ coverage data, and produce unified reports.
• Updated mssql_python/pybind/build.sh to support a coverage build mode (codecov or --coverage), enabling Clang coverage instrumentation for Linux builds and adjusting CMake configuration accordingly. [1] [2]

PR Automation Improvements:

• Refined the PR size label automation in .github/workflows/pr-format-check.yml to only update labels when necessary, reducing unnecessary label churn and improving logging for better traceability.

[Copilot]

Pull Request Overview

This PR introduces a comprehensive code coverage solution for the mssql-python project, enabling unified Python and C++ coverage reporting on macOS through GitHub Actions. The implementation adds automated coverage collection, merging, and PR commenting capabilities.

• Adds a new GitHub Actions workflow for macOS-based unified coverage testing on pull requests
• Implements a shell script to automate coverage collection, merging Python and C++ coverage data
• Updates the CMake build configuration to enable Clang coverage instrumentation on macOS

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
.github/workflows/pr-code-coverage.yml	New GitHub Actions workflow for running tests and generating unified coverage reports on macOS
generate_codecov.sh	New script to collect, merge, and generate HTML coverage reports from Python and C++ code
mssql_python/pybind/build.sh	Updated to include Clang coverage flags for C++ instrumentation on macOS

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