[ci] always supply defaults for parallelism vars (#132520)

.buildkite/scripts/steps/code_coverage/jest_parallel.sh

@@ -2,8 +2,8 @@
 
 set -uo pipefail
 
-JOB=$BUILDKITE_PARALLEL_JOB
-JOB_COUNT=$BUILDKITE_PARALLEL_JOB_COUNT
+JOB=${BUILDKITE_PARALLEL_JOB:-0}
+JOB_COUNT=${BUILDKITE_PARALLEL_JOB_COUNT:-1}
 
 # a jest failure will result in the script returning an exit code of 10
 
@@ -35,4 +35,4 @@ while read -r config; do
 # uses heredoc to avoid the while loop being in a sub-shell thus unable to overwrite exitCode
 done <<< "$(find src x-pack packages -name jest.config.js -not -path "*/__fixtures__/*" | sort)"
 
-exit $exitCode
+exit $exitCode

.buildkite/scripts/steps/test/ftr_configs.sh

@@ -4,10 +4,10 @@ set -euo pipefail
 
 source .buildkite/scripts/steps/functional/common.sh
 
-export JOB_NUM=$BUILDKITE_PARALLEL_JOB
+export JOB_NUM=${BUILDKITE_PARALLEL_JOB:-0}
 export JOB=ftr-configs-${JOB_NUM}
 
-FAILED_CONFIGS_KEY="${BUILDKITE_STEP_ID}${BUILDKITE_PARALLEL_JOB:-0}"
+FAILED_CONFIGS_KEY="${BUILDKITE_STEP_ID}${JOB_NUM}"
 
 # a FTR failure will result in the script returning an exit code of 10
 exitCode=0

.buildkite/scripts/steps/test/jest.sh

@@ -8,6 +8,8 @@ is_test_execution_step
 
 .buildkite/scripts/bootstrap.sh
 
+JOB=${BUILDKITE_PARALLEL_JOB:-0}
+
 echo '--- Jest'
-checks-reporter-with-killswitch "Jest Unit Tests $((BUILDKITE_PARALLEL_JOB+1))" \
+checks-reporter-with-killswitch "Jest Unit Tests $((JOB+1))" \
   .buildkite/scripts/steps/test/jest_parallel.sh jest.config.js

.buildkite/scripts/steps/test/jest_integration.sh

@@ -8,6 +8,8 @@ is_test_execution_step
 
 .buildkite/scripts/bootstrap.sh
 
+JOB=${BUILDKITE_PARALLEL_JOB:-0}
+
 echo '--- Jest Integration Tests'
-checks-reporter-with-killswitch "Jest Integration Tests $((BUILDKITE_PARALLEL_JOB+1))" \
+checks-reporter-with-killswitch "Jest Integration Tests $((JOB+1))" \
   .buildkite/scripts/steps/test/jest_parallel.sh jest.integration.config.js

.buildkite/scripts/steps/test/jest_parallel.sh

@@ -2,7 +2,7 @@
 
 set -euo pipefail
 
-export JOB=$BUILDKITE_PARALLEL_JOB
+export JOB=${BUILDKITE_PARALLEL_JOB:-0}
 
 # a jest failure will result in the script returning an exit code of 10
 exitCode=0