diff --git a/tests/common.mak b/tests/common.mak
index 39018d39..d0cc9fe1 100644
--- a/tests/common.mak
+++ b/tests/common.mak
@@ -40,10 +40,11 @@ endif
 ifneq ($(COVER_DB),)
 export PERL_COVER_ARGS := -MDevel::Cover=-db,$(COVER_DB),-coverage,statement,branch,condition,subroutine,-silent,1
 EXEC_COVER := perl ${PERL_COVER_ARGS}
-PYCOVER = COVERAGE_FILE=$(PYCOV_DB) coverage run --branch --append
+export COVERAGE_COMMAND = $(shell which coverage 2>&1 > /dev/null ; if [ 0 -eq $$? ] ; then echo coverage ; else echo python3-coverage ; fi )
+PYCOVER = COVERAGE_FILE=$(PYCOV_DB) ${COVERAGE_COMMAND} run --branch --append
+#$(warning assigned PYCOVER='$(PYCOVER)')
 endif
 
-
 export TOPDIR TESTDIR
 export PARENTDIR    := $(dir $(patsubst %/,%,$(TOPDIR)))
 export RELDIR       := $(TESTDIR:$(PARENTDIR)%=%)
diff --git a/tests/gendiffcov/errs/msgtest.sh b/tests/gendiffcov/errs/msgtest.sh
index 212b5de7..757db3ca 100755
--- a/tests/gendiffcov/errs/msgtest.sh
+++ b/tests/gendiffcov/errs/msgtest.sh
@@ -752,6 +752,7 @@ if [ 0 != $? ] ; then
         exit 1
     fi
 fi
+
 if [ -d mycache ] ; then
     find mycache -type f -exec chmod ugo+r {} \;
 fi
diff --git a/tests/gendiffcov/simple/script.sh b/tests/gendiffcov/simple/script.sh
index facc347a..f86d6dff 100755
--- a/tests/gendiffcov/simple/script.sh
+++ b/tests/gendiffcov/simple/script.sh
@@ -1,139 +1,12 @@
 #!/bin/bash
 set +x
 
-CLEAN_ONLY=0
-COVER=
-
-PARALLEL='--parallel 0'
-PROFILE="--profile"
-LOCAL_COVERAGE=1
-KEEP_GOING=0
-
-#echo "CMD:  $0 $@"
-
-while [ $# -gt 0 ] ; do
-
-    OPT=$1
-    shift
-    case $OPT in
-
-        --clean | clean )
-            CLEAN_ONLY=1
-            ;;
-
-        -v | --verbose | verbose )
-            set -x
-            ;;
-
-        --keep-going | -k )
-            KEEP_GOING=1
-            ;;
-
-        --coverage )
-            if [[ "$1"x != 'x' && $1 != "-"*  ]] ; then
-               COVER_DB=$1
-               LOCAL_COVERAGE=0
-               shift
-            else
-                COVER_DB='cover_db.dat'
-            fi
-            export PYCOV_DB="${COVER_DB}_py"
-            COVER="perl -MDevel::Cover=-db,${COVER_DB},-coverage,statement,branch,condition,subroutine,-silent,1 "
-            PYCOVER="COVERAGE_FILE=$PYCOV_DB coverage run --branch --append"
-            ;;
-
-        --home | -home )
-            LCOV_HOME=$1
-            shift
-            if [ ! -f $LCOV_HOME/bin/lcov ] ; then
-                echo "LCOV_HOME '$LCOV_HOME' does not exist"
-                exit 1
-            fi
-            ;;
-
-        --no-parallel )
-            PARALLEL=''
-            ;;
-
-        --no-profile )
-            PROFILE=''
-            ;;
-
-        --llvm )
-            LLVM=1
-            module load como/tools/llvm-gnu/11.0.0-1
-            # seems to have been using same gcov version as gcc/4.8.3
-            module load gcc/4.8.3
-            #EXTRA_GCOV_OPTS="--gcov-tool '\"llvm-cov gcov\"'"
-            CXX="clang++"
-            ;;
-
-        * )
-            echo "Error: unexpected option '$OPT'"
-            exit 1
-            ;;
-    esac
-done
-
-if [[ "x" == ${LCOV_HOME}x ]] ; then
-       if [ -f ../../../bin/lcov ] ; then
-           LCOV_HOME=../../..
-       else
-           LCOV_HOME=../../../../releng/coverage/lcov
-       fi
-fi
-LCOV_HOME=`(cd ${LCOV_HOME} ; pwd)`
-
-if [[ ! ( -d $LCOV_HOME/bin && -d $LCOV_HOME/lib && -x $LCOV_HOME/bin/genhtml && ( -f $LCOV_HOME/lib/lcovutil.pm || -f $LCOV_HOME/lib/lcov/lcovutil.pm ) ) ]] ; then
-    echo "LCOV_HOME '$LCOV_HOME' seems not to be invalid"
-    exit 1
-fi
-
-export PATH=${LCOV_HOME}/bin:${LCOV_HOME}/share:${PATH}
-export MANPATH=${MANPATH}:${LCOV_HOME}/man
-
-ROOT=`pwd`
-PARENT=`(cd .. ; pwd)`
-if [ -f $LCOV_HOME/scripts/getp4version ] ; then
-    SCRIPT_DIR=$LCOV_HOME/scripts
-else
-    # running test from lcov install
-    SCRIPT_DIR=$LCOV_HOME/share/lcov/support-scripts
-    MD5_OPT='--version-script --md5'
-fi
-if [ 'x' == "x$GENHTML_TOOL" ] ; then
-    GENHTML_TOOL=${LCOV_HOME}/bin/genhtml
-    LCOV_TOOL=${LCOV_HOME}/bin/lcov
-    GENINFO_TOOL=${LCOV_HOME}/bin/geninfo
-    SPREADSHEET_TOOL=${SCRIPT_DIR}/spreadsheet.py
-fi
-
-# is this git or P4?
-git -C . rev-parse > /dev/null 2>&1
-if [ 0 == $? ] ; then
-    # this is git
-    GET_VERSION=${SCRIPT_DIR}/gitversion.pm
-    GET_VERSION_EXE=${SCRIPT_DIR}/gitversion
-    ANNOTATE=${SCRIPT_DIR}/gitblame.pm
-else
-    GET_VERSION=${SCRIPT_DIR}/getp4version
-    GET_VERSION_EXE=${SCRIPT_DIR}/getp4version
-    ANNOTATE=${SCRIPT_DIR}/p4annotate.pm
-fi
-CRITERIA=${SCRIPT_DIR}/criteria
-SELECT=${SCRIPT_DIR}/select.pm
-
-#PARALLEL=''
-#PROFILE="''
-
+source ../../common.tst
 
 rm -f test.cpp *.gcno *.gcda a.out *.info *.info.gz diff.txt diff_r.txt diff_broken.txt *.log *.err *.json dumper* results.xlsx annotate.{cpp,exe} c d ./cover_db_py names.data linked.cpp linked_diff.txt *.msg
 rm -rf ./baseline ./current ./differential* ./reverse ./diff_no_baseline ./no_baseline ./no_annotation ./no_owners differential_nobranch reverse_nobranch baseline-filter* noncode_differential* broken mismatchPath elidePath ./cover_db ./criteria* ./mismatched ./navigation differential_prop proportion ./annotate ./current-* ./current_prefix* select select2 html_report ./usage ./errOut ./noNames no_source linked linked_err linked_elide linked_dir failUnder expect_err expect recategorize
 
-if [ "x$COVER" != 'x' ] && [ 0 != $LOCAL_COVERAGE ] ; then
-    cover -delete -db $COVER_DB
-    rm -rf $PYCOV_DB
-fi
+clean_cover
 
 if [[ 1 == $CLEAN_ONLY ]] ; then
     exit 0
diff --git a/tests/py2lcov/py2lcov.sh b/tests/py2lcov/py2lcov.sh
index 2ec2246c..69959c4d 100755
--- a/tests/py2lcov/py2lcov.sh
+++ b/tests/py2lcov/py2lcov.sh
@@ -1,101 +1,30 @@
 #!/bin/bash
 set +x
 
-CLEAN_ONLY=0
-COVER=
-
-PARALLEL='--parallel 0'
-PROFILE="--profile"
-if [ 'x' == "x${COVER_DB}" ] ; then
-    COVER_DB='cover_db'
-fi
-if [ 'x' == "x${PYCOV_DB}" ] ; then
-    PYCOV_DB='pycov.dat'
-fi
-LOCAL_COVERAGE=1
-KEEP_GOING=0
-while [ $# -gt 0 ] ; do
-
-    OPT=$1
-    shift
-    case $OPT in
-
-        --clean | clean )
-            CLEAN_ONLY=1
-            ;;
-
-        -v | --verbose | verbose )
-            set -x
-            ;;
-
-        -k | --keep-going )
-            KEEP_GOING=1
-            ;;
-
-        --coverage )
-            #COVER="perl -MDevel::Cover "
-            if [[ "$1"x != 'x' && $1 != "-"* ]] ; then
-               COVER_DB=$1
-               LOCAL_COVERAGE=0
-               shift
-            fi
-            COVER="perl -MDevel::Cover=-db,${COVER_DB},-coverage,statement,branch,condition,subroutine,-silent,1 "
-            PYCOV="COVERAGE_FILE=${PYCOV_DB} coverage run --branch --append"
-            #PYCOV="coverage run --data-file=${PYCOV_DB} --branch --append"
-            ;;
-
-        --home | -home )
-            LCOV_HOME=$1
-            shift
-            if [ ! -f $LCOV_HOME/bin/lcov ] ; then
-                echo "LCOV_HOME '$LCOV_HOME' does not exist"
-                exit 1
-            fi
-            ;;
-
-        --no-parallel )
-            PARALLEL=''
-            ;;
-
-        --no-profile )
-            PROFILE=''
-            ;;
-
-        * )
-            echo "Error: unexpected option '$OPT'"
-            exit 1
-            ;;
-    esac
-done
-
-if [ "x" == "x$LCOV_HOME" ] ; then
-       if [ -f ../../bin/lcov ] ; then
-           LCOV_HOME=../..
-       else
-           LCOV_HOME=../../../releng/coverage/lcov
-       fi
+if [[ "x" == ${LCOV_HOME}x ]] ; then
+    if [ -f ../../bin/lcov ] ; then
+        LCOV_HOME=../..
+    fi
 fi
 
-LCOV_HOME=`(cd ${LCOV_HOME} ; pwd)`
+source ../common.tst
 
-if [ 'x' == "x$PY2LCOV_TOOL" ] ; then
-    GENHTML_TOOL=${LCOV_HOME}/bin/genhtml
-    LCOV_TOOL=${LCOV_HOME}/bin/lcov
-    PERLLCOV_TOOL=${LCOV_HOME}/bin/perl2lcov
-    PY2LCOV_TOOL=${LCOV_HOME}/bin/py2lcov
+rm -rf *.xml* *.dat *.info *.json __pycache__ help.txt *.pyc my_cache rpt1 rpt2
+
+clean_cover
+
+if [[ 1 == $CLEAN_ONLY ]] ; then
+    exit 0
 fi
+
 PY2LCOV_SCRIPT=${LCOV_HOME}/bin/py2lcov
 
-if [ -f $LCOV_HOME/scripts/getp4version ] ; then
-    SCRIPT_DIR=$LCOV_HOME/scripts
-else
+if [ ! -f $LCOV_HOME/scripts/getp4version ] ; then
     # running test from lcov install
-    SCRIPT_DIR=$LCOV_HOME/share/lcov/support-scripts
     MD5_OPT=',--md5'
 fi
 # is this git or P4?
-git -C . rev-parse > /dev/null 2>&1
-if [ 0 == $? ] ; then
+if [ 1 == "$USE_GIT" ] ; then
     # this is git
     VERSION="--version-script ${SCRIPT_DIR}/gitversion${MD5_OPT}"
     ANNOTATE="--annotate-script ${SCRIPT_DIR}/gitblame.pm,--cache,my_cache"
@@ -105,46 +34,27 @@ else
     DEPOT=",."
 fi
 
+if [ $IS_GIT == 0 ] && [ $IS_P4 == 0 ] ; then
+    VERSION=
+    ANNOTATE="$ANNOTATE --ignore annotate"
+fi
 
 if [ ! -x $PY2LCOV_SCRIPT ] ; then
     echo "missing py2lcov script - dying"
     exit 1
 fi
 
-if [[ ! ( -d $LCOV_HOME/bin && -d $LCOV_HOME/lib && -x $LCOV_HOME/bin/genhtml && -f $LCOV_HOME/lib/lcovutil.pm ) ]] ; then
-    echo "LCOV_HOME '$LCOV_HOME' seems not to be invalid"
-    exit 1
-fi
-
-export PATH=${LCOV_HOME}/bin:${LCOV_HOME}/share:${PATH}
-export MANPATH=${MANPATH}:${LCOV_HOME}/man
-
-if [ 'x' == "x$GENHTML_TOOL" ] ; then
-    GENHTML_TOOL=${LCOV_HOME}/bin/genhtml
-    LCOV_TOOL=${LCOV_HOME}/bin/lcov
-    GENINFO_TOOL=${LCOV_HOME}/bin/geninfo
-fi
-
-ROOT=`pwd`
-PARENT=`(cd .. ; pwd)`
-
 LCOV_OPTS="--branch-coverage $PARALLEL $PROFILE"
 
-rm -rf *.xml* *.dat *.info *.json __pycache__ help.txt *.pyc my_cache rpt1 rpt2
-
-if [ "x$COVER" != 'x' ] && [ 0 != $LOCAL_COVERAGE ] ; then
-    cover -delete
-    rm -rf pycov
-fi
-
-if [[ 1 == $CLEAN_ONLY ]] ; then
-    exit 0
-fi
 
-CMD='coverage'
-which $CMD
-if [ 0 != $? ] ; then
-    CMD='python3-coverage' # ubuntu?
+if [ '' != "${COVERAGE_COMMAND}" ] ; then
+    CMD=${COVERAGE_COMMAND}
+else
+    CMD='coverage'
+    which $CMD
+    if [ 0 != $? ] ; then
+        CMD='python3-coverage' # ubuntu?
+    fi
 fi
 which $CMD
 if [ 0 != $? ] ; then
@@ -161,7 +71,7 @@ if [ 0 != $? ] ; then
         exit 1
     fi
 fi
-eval ${PYCOV} ${PY2LCOV_TOOL} -o functions.info --cmd $CMD functions.dat $VERSION
+eval COVERAGE_COMMAND=$CMD ${PYCOV} ${PY2LCOV_TOOL} -o functions.info --cmd $CMD functions.dat $VERSION
 if [ 0 != $? ] ; then
     echo "py2lcov failed function example"
     if [ 0 == $KEEP_GOING ] ; then