assume this file being empty is the main problem

Author: jettero

.pipeline

@@ -49,9 +49,11 @@ pipeline {
                     if [[ $(git show -s --format='%s%n%b' "${LHS}..${RHS}") =~ LINT-FULL ]]
                     then find hubblestack -name "*.py"
                     else find hubblestack -name "*.py" -print0 | xargs -r0 git diff --name-only "$LHS" "$RHS"
-                    fi > tests/unittests/output/relevant-files.txt
+                    fi > relevant-files.txt
                     '''
-                sh '''mkdir -vp tests/unittests/output'''
+                sh '''mkdir -vp tests/unittests/output
+                      cp relevant-files.txt tests/unittests/output
+                   '''
             }
         }
         stage('lint/test') {
@@ -71,9 +73,14 @@ pipeline {
                     steps {
                         sh '''#!/bin/bash
                             source ./venv/bin/activate
-                            < tests/unittests/output/relevant-files.txt  xargs -r pylint --output-format=json \
-                                > tests/unittests/output/pylint.json
-                            x=$?
+                            if grep -q . relevant-files.txt; then
+                                < relevant-files.txt  xargs -r pylint --output-format=json \
+                                    > tests/unittests/output/pylint.json
+                                x=$?
+                            else
+                                echo "[]" > tests/unittests/output/pylint.json
+                                x=0
+                            fi
                             python ./tests/automation/pylint-json-to-html tests/unittests/output/pylint.json
                             exit $x
                             '''
@@ -84,12 +91,17 @@ pipeline {
                         catchError(buildResult: 'SUCCESS', stageResult: 'FAILURE') {
                             sh '''#!/bin/bash
                                 source ./venv/bin/activate
-                                < tests/unittests/output/relevant-files.txt  xargs -r bandit -lif html \
-                                  > tests/unittests/output/bandit.html
-                                x=$?
-                                cp tests/static/bandit.css tests/unittests/output/bandit.css
-                                sed -i -e '/<style/,/<.style/c<link rel="stylesheet" href="bandit.css">' \
-                                  tests/unittests/output/bandit.html
+                                if grep -q . relevant-files.txt; then
+                                    < relevant-files.txt  xargs -r bandit -lif html \
+                                      > tests/unittests/output/bandit.html
+                                    x=$?
+                                    cp tests/static/bandit.css tests/unittests/output/bandit.css
+                                    sed -i -e '/<style/,/<.style/c<link rel="stylesheet" href="bandit.css">' \
+                                      tests/unittests/output/bandit.html
+                                else
+                                    echo "<p>did not run</p>" > tests/unittests/output/bandit.html
+                                    x=0
+                                fi
                                 exit $x
                                 '''
                         }