[coverage] Add use_coverage flag to add --coverage to clang builds. (#17935)
* [coverage] Add use_coverage flag to add --coverage to clang builds.
* [coverage] Add -o option to run lcov in a prebuilt output directory.
* [coverage] Fixes for review comments.
* [coverage] Rephrase use_coverage comment.
diff --git a/scripts/build_coverage.sh b/scripts/build_coverage.sh
new file mode 100755
index 0000000..9beca4a
--- /dev/null
+++ b/scripts/build_coverage.sh
@@ -0,0 +1,79 @@
+#!/usr/bin/env bash
+
+#
+# Copyright (c) 2022 Project CHIP Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+set -e
+
+_normpath() {
+ python -c "import os.path; print(os.path.normpath('$@'))"
+}
+
+CHIP_ROOT=$(_normpath "$(dirname "$0")/..")
+OUTPUT_ROOT="$CHIP_ROOT/out/coverage"
+COVERAGE_ROOT="$OUTPUT_ROOT/coverage"
+skip_gn=false
+
+help() {
+
+ echo "Usage: $file_name [ options ... ]"
+
+ echo "General Options:
+ -h, --help Display this information.
+Input Options:
+ -o, --output_root Set the build output directory. When set manually, performs only lcov stage
+ on provided build output. Assumes output_root has been built with 'use_coverage=true'
+ and that 'ninja check' was run.
+ "
+}
+
+file_name=${0##*/}
+
+while (($#)); do
+ case $1 in
+ --help | -h)
+ help
+ exit 1
+ ;;
+ --output_root | -o)
+ OUTPUT_ROOT=$2
+ COVERAGE_ROOT="$OUTPUT_ROOT/coverage"
+ skip_gn=true
+ shift
+ ;;
+ -*)
+ help
+ echo "Unknown Option \"$1\""
+ exit 1
+ ;;
+ esac
+ shift
+done
+
+# Ensure we have a compilation environment
+source "$CHIP_ROOT/scripts/activate.sh"
+
+# Generates ninja files
+if [ "$skip_gn" == false ]; then
+ gn --root="$CHIP_ROOT" gen "$OUTPUT_ROOT" --args='use_coverage=true'
+ ninja -C "$OUTPUT_ROOT" check
+fi
+
+mkdir -p "$COVERAGE_ROOT"
+lcov --initial --capture --directory "$OUTPUT_ROOT/obj" --output-file "$COVERAGE_ROOT/lcov_base.info"
+lcov --capture --directory "$OUTPUT_ROOT"/obj --output-file "$COVERAGE_ROOT/lcov_test.info"
+lcov --add-tracefile "$COVERAGE_ROOT/lcov_base.info" --add-tracefile "$COVERAGE_ROOT/lcov_test.info" --output-file "$COVERAGE_ROOT/lcov_final.info"
+genhtml "$COVERAGE_ROOT/lcov_final.info" --output-directory "$COVERAGE_ROOT/html"
