codecov.yml

#
# Licensed under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#
# Copyright (c) 2025 Alan de Freitas (alandefreitas@gmail.com)
#
# Official repository: https://github.com/cppalliance/mrdocs
#

# Codecov Configuration
# https://docs.codecov.com/docs/codecovyml-reference
#
# Patch Coverage Threshold Rationale
# ==================================
#
# We allow a small threshold for patch coverage NOT because reduced coverage
# is acceptable, but because some lines are inherently uncoverable and
# produce false positives:
#
#   - Class declarations (e.g., `class Foo : public Bar`)
#   - Struct declarations (e.g., `struct MyTest`)
#   - Access specifiers (`public:`, `private:`)
#   - Pure virtual method declarations
#   - Opening/closing braces on their own lines
#
# These are not executable code - they don't generate machine instructions -
# yet coverage tools (gcov) report them as "uncovered lines."
#
# Preferred Solutions (in order)
# ------------------------------
#
# 1st best: Configure gcov/lcov to exclude declarations from coverage
#           tracking entirely, so they never appear as uncovered lines.
#           This would eliminate false positives at the source.
#           Status: Not currently available/configured.
#
# 2nd best: Use an absolute threshold (e.g., "allow up to 5 uncovered lines")
#           rather than a percentage. This would be precise and predictable.
#           Status: Codecov only supports percentage-based thresholds.
#
# 3rd best: Use a percentage-based threshold (what we implement below).
#           The threshold is set small enough that any real logic
#           (conditionals, loops, function bodies, error paths) that isn't
#           covered will still trigger a failure. Only trivial declaration
#           noise should pass through.
#
# With typical PR sizes, a 90% patch target achieves a similar effect to
# allowing ~5 uncovered lines in a 50-line change.

coverage:
  status:
    # Project-wide coverage should not decrease
    project:
      default:
        threshold: 1%

    # Patch coverage: only applies to new/modified lines in the PR
    patch:
      default:
        target: 90%

ignore:
  # This file contains a bunch of Boost.Describe macro invocations
  # which are not executable code and produce false positives in
  # coverage reports.
  - "src/lib/Support/Reflection/Reflection.hpp"