test: allow coverage threshold to be enforced

If COV_ENFORCE_THRESHOLD is set, tests run in coverage mode will exit with an error, if line coverage is below the percentage threshold. PR-URL: #25675 Reviewed-By: Refael Ackermann <refack@gmail.com> Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>

Author: bcoe

Makefile

@@ -215,7 +215,7 @@ coverage-build: all
 coverage-build-js:
 mkdir -p node_modules
 if [ ! -d node_modules/c8 ]; then \
-$(NODE) ./deps/npm install c8@next --no-save --no-package-lock;\
+$(NODE) ./deps/npm install c8 --no-save --no-package-lock;\
 fi
 
 .PHONY: coverage-test
@@ -240,12 +240,17 @@ coverage-test: coverage-build
 @grep -A3 Lines coverage/cxxcoverage.html | grep style \
 | sed 's/<[^>]*>//g'| sed 's/ //g'
 
+COV_REPORT_OPTIONS = --reporter=html \
+--temp-directory=out/$(BUILDTYPE)/.coverage --omit-relative=false \
+--resolve=./lib --exclude="deps/" --exclude="test/" --exclude="tools/" \
+--wrapper-length=0
+ifdef COV_ENFORCE_THRESHOLD
+ COV_REPORT_OPTIONS += --check-coverage --lines=$(COV_ENFORCE_THRESHOLD)
+endif
+
 .PHONY: coverage-report-js
 coverage-report-js:
-$(NODE) ./node_modules/.bin/c8 report --reporter=html \
---temp-directory=out/$(BUILDTYPE)/.coverage --omit-relative=false \
---resolve=./lib --exclude="deps/" --exclude="test/" --exclude="tools/" \
---wrapper-length=0
+$(NODE) ./node_modules/.bin/c8 report $(COV_REPORT_OPTIONS)
 
 .PHONY: cctest
 # Runs the C++ tests using the built `cctest` executable.