From b14728d999003dd206450ce17895ad0f65549893 Mon Sep 17 00:00:00 2001
From: mehrdadn <mehrdadn@users.noreply.github.com>
Date: Tue, 21 Jul 2020 19:56:41 -0700
Subject: [PATCH] Shellcheck quoting (#9596)

* Fix SC2006: Use $(...) notation instead of legacy backticked `...`.

* Fix SC2016: Expressions don't expand in single quotes, use double quotes for that.

* Fix SC2046: Quote this to prevent word splitting.

* Fix SC2053: Quote the right-hand side of == in [[ ]] to prevent glob matching.

* Fix SC2068: Double quote array expansions to avoid re-splitting elements.

* Fix SC2086: Double quote to prevent globbing and word splitting.

* Fix SC2102: Ranges can only match single chars (mentioned due to duplicates).

* Fix SC2140: Word is of the form "A"B"C" (B indicated). Did you mean "ABC" or "A\"B\"C"?

* Fix SC2145: Argument mixes string and array. Use * or separate argument.

* Fix SC2209: warning: Use var=$(command) to assign output (or quote to assign string).

Co-authored-by: Mehrdad <noreply@github.com>
---
 ci/asan_tests/run_asan_tests.sh               |  2 +-
 ci/jenkins_tests/entry_point.sh               |  6 +-
 ci/jenkins_tests/run_doc_tests.sh             | 14 ++--
 ci/jenkins_tests/run_multi_node_tests.sh      |  2 +-
 ci/jenkins_tests/run_sgd_tests.sh             | 40 +++++-----
 ci/jenkins_tests/run_tune_tests.sh            | 79 +++++++++----------
 ci/keep_alive                                 |  2 +-
 ci/suppress_output                            | 10 +--
 ci/travis/bazel-format.sh                     | 12 +--
 ci/travis/build-autoscaler-images.sh          | 30 +++----
 ci/travis/ci.sh                               |  9 ++-
 ci/travis/format.sh                           |  8 +-
 ci/travis/install-bazel.sh                    |  2 +-
 ci/travis/install-dependencies.sh             |  4 +-
 doc/azure/azure-init.sh                       | 16 ++--
 doc/dev/bin/pip_download_test.sh              |  2 +-
 doc/dev/download_wheels.sh                    | 16 ++--
 doc/examples/lm/ray_train.sh                  |  6 +-
 doc/tools/install-prometheus-server.sh        |  2 +-
 java/generate_jni_header_files.sh             | 10 +--
 java/test.sh                                  |  8 +-
 python/build-wheel-macos.sh                   | 10 +--
 python/build-wheel-manylinux1.sh              |  6 +-
 .../autoscaler/kubernetes/kubectl-rsync.sh    |  4 +-
 setup_hooks.sh                                |  4 +-
 src/ray/test/run_object_manager_tests.sh      |  8 +-
 src/ray/test/run_object_manager_valgrind.sh   |  8 +-
 .../src/test/run_streaming_queue_test.sh      | 11 ++-
 28 files changed, 166 insertions(+), 165 deletions(-)

diff --git a/ci/asan_tests/run_asan_tests.sh b/ci/asan_tests/run_asan_tests.sh
index 2333a2bb8..ff67c442a 100755
--- a/ci/asan_tests/run_asan_tests.sh
+++ b/ci/asan_tests/run_asan_tests.sh
@@ -52,7 +52,7 @@ asan_recompile() {
 }
 
 if [ 0 -lt "$#" ]; then
-  asan_"$@"
+  "asan_$1" "${@:2}"
 else
   echo "Available commands: setup, run, recompile"
 fi
diff --git a/ci/jenkins_tests/entry_point.sh b/ci/jenkins_tests/entry_point.sh
index 4813ff18d..78c09b3c2 100755
--- a/ci/jenkins_tests/entry_point.sh
+++ b/ci/jenkins_tests/entry_point.sh
@@ -32,13 +32,13 @@ function retry {
 }
 
 if [[ ! -z "$RUN_TUNE_TESTS" ]]; then 
-    retry bash $ROOT_DIR/run_tune_tests.sh ${MEMORY_SIZE} ${SHM_SIZE}
+    retry bash "$ROOT_DIR"/run_tune_tests.sh ${MEMORY_SIZE} ${SHM_SIZE}
 fi
 
 if [[ ! -z "$RUN_DOC_TESTS" ]]; then
-    retry bash $ROOT_DIR/run_doc_tests.sh ${MEMORY_SIZE} ${SHM_SIZE}
+    retry bash "$ROOT_DIR"/run_doc_tests.sh ${MEMORY_SIZE} ${SHM_SIZE}
 fi
 
 if [[ ! -z "$RUN_SGD_TESTS" ]]; then
-    retry bash $ROOT_DIR/run_sgd_tests.sh ${MEMORY_SIZE} ${SHM_SIZE}
+    retry bash "$ROOT_DIR"/run_sgd_tests.sh ${MEMORY_SIZE} ${SHM_SIZE}
 fi
\ No newline at end of file
diff --git a/ci/jenkins_tests/run_doc_tests.sh b/ci/jenkins_tests/run_doc_tests.sh
index e1444b8c8..519826441 100755
--- a/ci/jenkins_tests/run_doc_tests.sh
+++ b/ci/jenkins_tests/run_doc_tests.sh
@@ -25,7 +25,7 @@ if [ "$DOCKER_SHA" == "" ]; then
 
     # Add Ray source
     git rev-parse HEAD > ./docker/tune_test/git-rev
-    git archive -o ./docker/tune_test/ray.tar $(git rev-parse HEAD)
+    git archive -o ./docker/tune_test/ray.tar "$(git rev-parse HEAD)"
     if [ "$CI_BUILD_FROM_SOURCE" == "1" ]; then
       DOCKER_SHA=$(docker build --no-cache -q -t ray-project/tune_test docker/tune_test -f docker/tune_test/build_from_source.Dockerfile)
     else
@@ -33,23 +33,23 @@ if [ "$DOCKER_SHA" == "" ]; then
     fi
 fi
 
-echo "Using Docker image" $DOCKER_SHA
+echo "Using Docker image" "$DOCKER_SHA"
 
 
 ######################## EXAMPLE TESTS #################################
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/doc/examples/plot_pong_example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/doc/examples/plot_parameter_server.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/doc/examples/plot_hyperparameter.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/doc/examples/doc_code/torch_example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/doc/examples/doc_code/tf_example.py
 
diff --git a/ci/jenkins_tests/run_multi_node_tests.sh b/ci/jenkins_tests/run_multi_node_tests.sh
index 23299a5a1..f04b0e645 100755
--- a/ci/jenkins_tests/run_multi_node_tests.sh
+++ b/ci/jenkins_tests/run_multi_node_tests.sh
@@ -9,4 +9,4 @@ export RUN_DOC_TESTS=1
 export RUN_SGD_TESTS=1
 export CI_BUILD_FROM_SOURCE=1
 
-bash $ROOT_DIR/entry_point.sh
+bash "$ROOT_DIR"/entry_point.sh
diff --git a/ci/jenkins_tests/run_sgd_tests.sh b/ci/jenkins_tests/run_sgd_tests.sh
index 12a35c310..be660cb66 100755
--- a/ci/jenkins_tests/run_sgd_tests.sh
+++ b/ci/jenkins_tests/run_sgd_tests.sh
@@ -25,7 +25,7 @@ if [ "$DOCKER_SHA" == "" ]; then
 
     # Add Ray source
     git rev-parse HEAD > ./docker/tune_test/git-rev
-    git archive -o ./docker/tune_test/ray.tar $(git rev-parse HEAD)
+    git archive -o ./docker/tune_test/ray.tar "$(git rev-parse HEAD)"
     if [ "$CI_BUILD_FROM_SOURCE" == "1" ]; then
       DOCKER_SHA=$(docker build --no-cache -q -t ray-project/tune_test docker/tune_test -f docker/tune_test/build_from_source.Dockerfile)
     else
@@ -33,62 +33,62 @@ if [ "$DOCKER_SHA" == "" ]; then
     fi
 fi
 
-echo "Using Docker image" $DOCKER_SHA
+echo "Using Docker image" "$DOCKER_SHA"
 
 
 ######################## SGD TESTS #################################
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python -m pytest /ray/python/ray/util/sgd/tests
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/raysgd_torch_signatures.py
 
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
 python /ray/python/ray/util/sgd/torch/examples/image_models/train.py --no-gpu --mock-data --smoke-test --ray-num-workers=2 --model mobilenetv3_small_075 data
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/train_example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/train_example.py --num-workers=2
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/tune_example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/tune_example.py --num-workers=2
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/cifar_pytorch_example.py --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/cifar_pytorch_example.py --smoke-test --num-workers=2
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/cifar_pytorch_pbt.py --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/dcgan.py --smoke-test --num-workers=2
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/torch/examples/benchmarks/benchmark.py --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/tf/examples/tensorflow_train_example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/tf/examples/tensorflow_train_example.py --num-replicas=2
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/tf/examples/tensorflow_train_example.py --tune
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/tf/examples/cifar_tf_example.py --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/tf/examples/cifar_tf_example.py --num-replicas 2 --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/util/sgd/tf/examples/cifar_tf_example.py --num-replicas 2 --smoke-test --augment-data
diff --git a/ci/jenkins_tests/run_tune_tests.sh b/ci/jenkins_tests/run_tune_tests.sh
index 1cc12c0cc..7998c0c0e 100755
--- a/ci/jenkins_tests/run_tune_tests.sh
+++ b/ci/jenkins_tests/run_tune_tests.sh
@@ -25,8 +25,7 @@ if [ "$DOCKER_SHA" == "" ]; then
 
     # Add Ray source
     git rev-parse HEAD > ./docker/tune_test/git-rev
-    git archive -o ./docker/tune_test/ray.tar $(git rev-parse HEAD)
-
+    git archive -o ./docker/tune_test/ray.tar "$(git rev-parse HEAD)"
     if [ "$CI_BUILD_FROM_SOURCE" == "1" ]; then
       DOCKER_SHA=$(docker build --no-cache -q -t ray-project/tune_test docker/tune_test -f docker/tune_test/build_from_source.Dockerfile)
     else
@@ -34,142 +33,142 @@ if [ "$DOCKER_SHA" == "" ]; then
     fi
 fi
 
-echo "Using Docker image" $DOCKER_SHA
+echo "Using Docker image" "$DOCKER_SHA"
 
 ######################## TUNE TESTS #################################
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     pytest /ray/python/ray/tune/tests/test_actor_reuse.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     pytest /ray/python/ray/tune/tests/test_tune_restore.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/tests/example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     bash -c 'pip install -U tensorflow && python /ray/python/ray/tune/tests/test_logger.py'
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     bash -c 'pip install -U tensorflow==1.15 && python /ray/python/ray/tune/tests/test_logger.py'
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     bash -c 'pip install -U tensorflow==1.14 && python /ray/python/ray/tune/tests/test_logger.py'
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 -e MPLBACKEND=Agg $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 -e MPLBACKEND=Agg "$DOCKER_SHA" \
     python /ray/python/ray/tune/tests/tutorial.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/pbt_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/hyperband_example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/async_hyperband_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/tf_mnist_example.py --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/lightgbm_example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/xgboost_example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/logging_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/mlflow_example.py
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/bayesopt_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/cifar10_pytorch.py --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/hyperopt_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/doc/source/tune/_tutorials/tune-sklearn.py
 
 # if [[ ! -z "$SIGOPT_KEY" ]]; then
-#     $SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 -e SIGOPT_KEY $DOCKER_SHA \
+#     $SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 -e SIGOPT_KEY "$DOCKER_SHA" \
 #         python /ray/python/ray/tune/examples/sigopt_example.py \
 #         --smoke-test
 # fi
 
 # Runs only on Python3
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/nevergrad_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/tune_mnist_keras.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/mnist_pytorch.py --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/mnist_pytorch_lightning.py --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/mnist_pytorch_trainable.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/genetic_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/skopt_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/dragonfly_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/zoopt_example.py \
     --smoke-test
 
 # Commenting out because flaky
-# $SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+# $SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
 #     python /ray/python/ray/tune/examples/pbt_memnn_example.py \
 #     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/pbt_convnet_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/hyperband_function_example.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/pbt_function.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/pbt_dcgan_mnist/pbt_dcgan_mnist.py \
     --smoke-test
 
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/ci/long_running_distributed_tests/workloads/pytorch_pbt_failure.py \
     --smoke-test
 
 # uncomment once statsmodels is updated.
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     python /ray/python/ray/tune/examples/bohb_example.py
 
 # Moved to bottom because flaky
-$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 $DOCKER_SHA \
+$SUPPRESS_OUTPUT docker run --rm --shm-size=${SHM_SIZE} --memory=${MEMORY_SIZE} --memory-swap=-1 "$DOCKER_SHA" \
     pytest /ray/python/ray/tune/tests/test_cluster.py
diff --git a/ci/keep_alive b/ci/keep_alive
index a8198fd97..4489ea904 100755
--- a/ci/keep_alive
+++ b/ci/keep_alive
@@ -5,7 +5,7 @@ PID=$$
 
 # Print output to avoid travis killing us
 watchdog() {
-    for i in `seq 2 2 150`; do
+    for i in $(seq 2 2 150); do
         sleep 120
         echo "(running, ${i}m total)"
     done
diff --git a/ci/suppress_output b/ci/suppress_output
index 583bd6275..15b0825b9 100755
--- a/ci/suppress_output
+++ b/ci/suppress_output
@@ -1,17 +1,17 @@
 #!/bin/bash
 # Run a command, suppressing output unless it hangs or crashes.
 
-TMPFILE=`mktemp`
+TMPFILE="$(mktemp)"
 PID=$$
 
 # Print output to avoid travis killing us
 watchdog() {
-    for i in `seq 5 5 150`; do
+    for i in $(seq 5 5 150); do
         sleep 300
         echo "This command has been running for more than $i minutes..."
     done
     echo "Command timed out after 2.5h, dumping logs:"
-    cat $TMPFILE
+    cat "$TMPFILE"
     echo "TIMED OUT"
     kill -SIGKILL $PID
 }
@@ -19,11 +19,11 @@ watchdog() {
 watchdog & 2>/dev/null
 WATCHDOG_PID=$!
 
-time "$@" >$TMPFILE 2>&1
+time "$@" >"$TMPFILE" 2>&1
 
 CODE=$?
 if [ $CODE != 0 ]; then
-    tail -n 2000 $TMPFILE
+    tail -n 2000 "$TMPFILE"
     echo "FAILED $CODE"
     kill $WATCHDOG_PID
     exit $CODE
diff --git a/ci/travis/bazel-format.sh b/ci/travis/bazel-format.sh
index c31b1daf6..1ebcb68b7 100755
--- a/ci/travis/bazel-format.sh
+++ b/ci/travis/bazel-format.sh
@@ -17,7 +17,7 @@ function usage()
   echo
 }
 
-RUN_TYPE=diff
+RUN_TYPE="diff"
 
 # Parse options
 while [[ $# > 0 ]]; do
@@ -28,7 +28,7 @@ while [[ $# > 0 ]]; do
       exit 0
       ;;
     -c|--check)
-      RUN_TYPE=diff
+      RUN_TYPE="diff"
       ;;
     -f|--fix)
       RUN_TYPE=fix
@@ -43,8 +43,8 @@ while [[ $# > 0 ]]; do
   shift
 done
 
-pushd $ROOT_DIR/../..
-BAZEL_FILES="bazel/BUILD bazel/BUILD.arrow bazel/ray.bzl BUILD.bazel java/BUILD.bazel
- cpp/BUILD.bazel streaming/BUILD.bazel streaming/java/BUILD.bazel WORKSPACE"
-buildifier -mode=$RUN_TYPE -diff_command="diff -u" $BAZEL_FILES
+pushd "$ROOT_DIR"/../..
+BAZEL_FILES=(bazel/BUILD bazel/BUILD.arrow bazel/ray.bzl BUILD.bazel java/BUILD.bazel \
+ cpp/BUILD.bazel streaming/BUILD.bazel streaming/java/BUILD.bazel WORKSPACE)
+buildifier -mode=$RUN_TYPE -diff_command="diff -u" "${BAZEL_FILES[@]}"
 popd
diff --git a/ci/travis/build-autoscaler-images.sh b/ci/travis/build-autoscaler-images.sh
index 87428aa44..146b14d9e 100755
--- a/ci/travis/build-autoscaler-images.sh
+++ b/ci/travis/build-autoscaler-images.sh
@@ -6,7 +6,7 @@ set -e
 set -x
 
 SCRIPT_DIR=$(cd "$(dirname "${BASH_SOURCE:-$0}")"; pwd)
-ROOT_DIR=$(cd $SCRIPT_DIR/../../; pwd)
+ROOT_DIR=$(cd "$SCRIPT_DIR"/../../; pwd)
 DOCKER_USERNAME="raytravisbot"
 
 # We will only build and push when we are building branch build.
@@ -14,33 +14,33 @@ if [[ "$TRAVIS" == "true" && "$TRAVIS_PULL_REQUEST" == "false" ]]; then
     echo "$DOCKER_PASSWORD" | docker login -u "$DOCKER_USERNAME" --password-stdin
 
     wheel=$(cd $ROOT_DIR/.whl; ls | grep cp36m-manylinux)
-    commit_sha=$(echo $TRAVIS_COMMIT | head -c 6)
-    cp -r $ROOT_DIR/.whl $ROOT_DIR/docker/autoscaler/.whl
+    commit_sha=$(echo "$TRAVIS_COMMIT" | head -c 6)
+    cp -r "$ROOT_DIR"/.whl "$ROOT_DIR"/docker/autoscaler/.whl
 
     docker build -q -t rayproject/base-deps docker/base-deps
 
     docker build \
         --build-arg WHEEL_PATH=".whl/$wheel" \
         --build-arg WHEEL_NAME=$wheel \
-        -t rayproject/autoscaler:$commit_sha \
-        $ROOT_DIR/docker/autoscaler
+        -t rayproject/autoscaler:"$commit_sha" \
+        "$ROOT_DIR"/docker/autoscaler
 
-    docker tag rayproject/base-deps rayproject/base-deps:$commit_sha 
-    docker push rayproject/base-deps:$commit_sha
-    docker push rayproject/autoscaler:$commit_sha
+    docker tag rayproject/base-deps rayproject/base-deps:"$commit_sha" 
+    docker push rayproject/base-deps:"$commit_sha"
+    docker push rayproject/autoscaler:"$commit_sha"
 
 
     # We have a branch build, e.g. release/v0.7.0
     if [[ "$TRAVIS_BRANCH" != "master" ]]; then
        # Replace / in branch name to - so it is legal tag name
-       normalized_branch_name=$(echo $TRAVIS_BRANCH | sed -e "s/\//-/")
-       docker tag rayproject/autoscaler:$commit_sha rayproject/autoscaler:$normalized_branch_name
-       docker tag rayproject/base-deps:$commit_sha rayproject/base-deps:$normalized_branch_name
-       docker push rayproject/autoscaler:$normalized_branch_name
-       docker push rayproject/base-deps:$normalized_branch_name
+       normalized_branch_name=$(echo "$TRAVIS_BRANCH" | sed -e "s/\//-/")
+       docker tag rayproject/autoscaler:"$commit_sha" rayproject/autoscaler:"$normalized_branch_name"
+       docker tag rayproject/base-deps:"$commit_sha" rayproject/base-deps:"$normalized_branch_name"
+       docker push rayproject/autoscaler:"$normalized_branch_name"
+       docker push rayproject/base-deps:"$normalized_branch_name"
     else
-       docker tag rayproject/autoscaler:$commit_sha rayproject/autoscaler:latest
-       docker tag rayproject/base-deps:$commit_sha rayproject/base-deps:latest
+       docker tag rayproject/autoscaler:"$commit_sha" rayproject/autoscaler:latest
+       docker tag rayproject/base-deps:"$commit_sha" rayproject/base-deps:latest
        docker push rayproject/autoscaler:latest
        docker push rayproject/base-deps:latest
     fi
diff --git a/ci/travis/ci.sh b/ci/travis/ci.sh
index 4a21afdf8..d36e9efe5 100755
--- a/ci/travis/ci.sh
+++ b/ci/travis/ci.sh
@@ -312,7 +312,7 @@ lint_bazel() {
   # Run buildifier without affecting external environment variables
   (
     mkdir -p -- "${GOPATH}"
-    export PATH="${GOPATH}/bin":"${GOROOT}/bin":"${PATH}"
+    export PATH="${GOPATH}/bin:${GOROOT}/bin:${PATH}"
 
     # Build buildifier
     go get github.com/bazelbuild/buildtools/buildifier
@@ -329,8 +329,11 @@ lint_web() {
     . "${HOME}/.nvm/nvm.sh"
     install_npm_project
     nvm use --silent node
-    node_modules/.bin/eslint --max-warnings 0 $(find src -name "*.ts" -or -name "*.tsx")
-    node_modules/.bin/prettier --check $(find src -name "*.ts" -or -name "*.tsx")
+    local filenames
+    # shellcheck disable=SC2207
+    filenames=($(find src -name "*.ts" -or -name "*.tsx"))
+    node_modules/.bin/eslint --max-warnings 0 "${filenames[@]}"
+    node_modules/.bin/prettier --check "${filenames[@]}"
     node_modules/.bin/prettier --check public/index.html
   )
 }
diff --git a/ci/travis/format.sh b/ci/travis/format.sh
index 4102b5c5f..bdb44481d 100755
--- a/ci/travis/format.sh
+++ b/ci/travis/format.sh
@@ -21,7 +21,7 @@ check_command_exist() {
             echo "$1 is not a required dependency"
             exit 1
     esac
-    if ! [ -x "$(command -v $1)" ]; then
+    if ! [ -x "$(command -v "$1")" ]; then
         echo "$1 not installed. pip install $1==$VERSION"
         exit 1
     fi 
@@ -31,7 +31,7 @@ check_command_exist yapf
 check_command_exist flake8
 
 ver=$(yapf --version)
-if ! echo $ver | grep -q 0.23.0; then
+if ! echo "$ver" | grep -q 0.23.0; then
     echo "Wrong YAPF version installed: 0.23.0 is required, not $ver. $YAPF_DOWNLOAD_COMMAND_MSG"
     exit 1
 fi
@@ -52,7 +52,7 @@ YAPF_VERSION=$(yapf --version | awk '{print $2}')
 
 # params: tool name, tool version, required version
 tool_version_check() {
-    if [[ $2 != $3 ]]; then
+    if [ "$2" != "$3" ]; then
         echo "WARNING: Ray uses $1 $3, You currently are using $2. This might generate different results."
     fi
 }
@@ -62,7 +62,7 @@ tool_version_check "yapf" $YAPF_VERSION $YAPF_VERSION_REQUIRED
 
 if which clang-format >/dev/null; then
   CLANG_FORMAT_VERSION=$(clang-format --version | awk '{print $3}')
-  tool_version_check "clang-format" $CLANG_FORMAT_VERSION "7.0.0"
+  tool_version_check "clang-format" "$CLANG_FORMAT_VERSION" "7.0.0"
 else
     echo "WARNING: clang-format is not installed!"
 fi
diff --git a/ci/travis/install-bazel.sh b/ci/travis/install-bazel.sh
index 3cd4534e8..1a8ab6ef8 100755
--- a/ci/travis/install-bazel.sh
+++ b/ci/travis/install-bazel.sh
@@ -38,7 +38,7 @@ esac
     fi
   done
   if [ ! 0 -eq "${#missing_symlinks[@]}" ]; then
-    echo "error: expected symlink: ${missing_symlinks[@]}" 1>&2
+    echo "error: expected symlink: ${missing_symlinks[*]}" 1>&2
     echo "For a correct build, please run 'git config --local core.symlinks true' and re-run git checkout." 1>&2
     false
   fi
diff --git a/ci/travis/install-dependencies.sh b/ci/travis/install-dependencies.sh
index 4c613b1ee..96a78df25 100755
--- a/ci/travis/install-dependencies.sh
+++ b/ci/travis/install-dependencies.sh
@@ -159,7 +159,7 @@ install_nvm() {
       )
       printf "%s\n" \
         "export NVM_HOME=\"$(cygpath -w -- "${NVM_HOME}")\"" \
-        'nvm() { "${NVM_HOME}/nvm.exe" "$@"; }' \
+        "nvm() { \"\${NVM_HOME}/nvm.exe\" \"\$@\"; }" \
         > "${NVM_HOME}/nvm.sh"
     fi
   else
@@ -277,7 +277,7 @@ install_dependencies() {
   # Additional RLlib dependencies.
   if [ "${RLLIB_TESTING-}" = 1 ]; then
     pip install tensorflow-probability=="${TFP_VERSION-0.8}" gast==0.2.2 \
-      torch=="${TORCH_VERSION-1.4}" torchvision atari_py gym[atari] lz4 smart_open
+      torch=="${TORCH_VERSION-1.4}" torchvision atari_py "gym[atari]" lz4 smart_open
   fi
 
   # Additional streaming dependencies.
diff --git a/doc/azure/azure-init.sh b/doc/azure/azure-init.sh
index 4875e789d..7c0628200 100755
--- a/doc/azure/azure-init.sh
+++ b/doc/azure/azure-init.sh
@@ -7,11 +7,11 @@ RAY_HEAD_IP=$4
 TYPE=$5
 
 echo "Installing wheel..."
-sudo -u $USERNAME -i /bin/bash -l -c "conda init bash"
-sudo -u $USERNAME -i /bin/bash -l -c "conda activate $CONDA_ENV; pip install $WHEEL"
+sudo -u "$USERNAME" -i /bin/bash -l -c "conda init bash"
+sudo -u "$USERNAME" -i /bin/bash -l -c "conda activate $CONDA_ENV; pip install $WHEEL"
 
 echo "Setting up service scripts..."
-cat > /home/$USERNAME/ray-head.sh << EOM
+cat > /home/"$USERNAME"/ray-head.sh << EOM
 #!/bin/bash
 conda activate $CONDA_ENV
 
@@ -22,7 +22,7 @@ ulimit -n 65536
 ray start --head --redis-port=6379 --object-manager-port=8076 --num-gpus=\$NUM_GPUS --block --webui-host 0.0.0.0
 EOM
 
-cat > /home/$USERNAME/ray-worker.sh << EOM
+cat > /home/"$USERNAME"/ray-worker.sh << EOM
 #!/bin/bash
 conda activate $CONDA_ENV
 
@@ -39,7 +39,7 @@ do
 done
 EOM
 
-cat > /home/$USERNAME/tensorboard.sh << EOM
+cat > /home/"$USERNAME"/tensorboard.sh << EOM
 #!/bin/bash
 
 conda activate $CONDA_ENV
@@ -48,9 +48,9 @@ mkdir -p /home/$USERNAME/ray_results
 tensorboard --bind_all --logdir=/home/$USERNAME/ray_results
 EOM
 
-chmod +x /home/$USERNAME/ray-head.sh
-chmod +x /home/$USERNAME/ray-worker.sh
-chmod +x /home/$USERNAME/tensorboard.sh
+chmod +x /home/"$USERNAME"/ray-head.sh
+chmod +x /home/"$USERNAME"/ray-worker.sh
+chmod +x /home/"$USERNAME"/tensorboard.sh
 
 cat > /lib/systemd/system/ray.service << EOM
 [Unit]
diff --git a/doc/dev/bin/pip_download_test.sh b/doc/dev/bin/pip_download_test.sh
index 69e9dcf71..0690b4164 100755
--- a/doc/dev/bin/pip_download_test.sh
+++ b/doc/dev/bin/pip_download_test.sh
@@ -54,7 +54,7 @@ do
     echo "=========================================================\n\n\n"
 
     conda deactivate
-    conda remove -y --name ${env_name} --all
+    conda remove -y --name "${env_name}" --all
     if [ "$failed" = true ]; then
         echo "PYTHON ${PYTHON_VERSION} failed sanity check."
         exit 1
diff --git a/doc/dev/download_wheels.sh b/doc/dev/download_wheels.sh
index 5aa7f00a6..f55c6b839 100644
--- a/doc/dev/download_wheels.sh
+++ b/doc/dev/download_wheels.sh
@@ -11,13 +11,13 @@ if [[ -z "$RAY_VERSION" ]]; then
 fi
 
 # Make sure Linux wheels are downloadable without errors.
-wget https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp35-cp35m-manylinux1_x86_64.whl
-wget https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp36-cp36m-manylinux1_x86_64.whl
-wget https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp37-cp37m-manylinux1_x86_64.whl
-wget https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp38-cp38-manylinux1_x86_64.whl
+wget "https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp35-cp35m-manylinux1_x86_64.whl"
+wget "https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp36-cp36m-manylinux1_x86_64.whl"
+wget "https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp37-cp37m-manylinux1_x86_64.whl"
+wget "https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp38-cp38-manylinux1_x86_64.whl"
 # Make sure macos wheels are downloadable without errors.
-wget https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp35-cp35m-macosx_10_13_intel.whl
-wget https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp36-cp36m-macosx_10_13_intel.whl
-wget https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp37-cp37m-macosx_10_13_intel.whl
+wget "https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp35-cp35m-macosx_10_13_intel.whl"
+wget "https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp36-cp36m-macosx_10_13_intel.whl"
+wget "https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp37-cp37m-macosx_10_13_intel.whl"
 # Wheel name convention has been changed from Python 3.8.
-wget https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp38-cp38-macosx_10_13_x86_64.whl
+wget "https://s3-us-west-2.amazonaws.com/ray-wheels/releases/$RAY_VERSION/$RAY_HASH/ray-$RAY_VERSION-cp38-cp38-macosx_10_13_x86_64.whl"
diff --git a/doc/examples/lm/ray_train.sh b/doc/examples/lm/ray_train.sh
index 0437f31fa..8fe014007 100644
--- a/doc/examples/lm/ray_train.sh
+++ b/doc/examples/lm/ray_train.sh
@@ -11,9 +11,9 @@ SAVE_INTERVAL_UPDATES=1000 # save a checkpoint every N updates
 
 LOG_DIR=$HOME/efs/lm/log/
 DATA_DIR=$HOME/efs/lm/data-bin/wikitext-103/
-mkdir -p $LOG_DIR
+mkdir -p "$LOG_DIR"
 
-python $HOME/efs/lm/ray_train.py --fp16 $DATA_DIR \
+python "$HOME"/efs/lm/ray_train.py --fp16 "$DATA_DIR" \
     --task masked_lm --criterion masked_lm \
     --arch roberta_base --sample-break-mode complete --tokens-per-sample $TOKENS_PER_SAMPLE \
     --optimizer adam --adam-betas '(0.9, 0.98)' --adam-eps 1e-6 --clip-norm 0.0 \
@@ -23,4 +23,4 @@ python $HOME/efs/lm/ray_train.py --fp16 $DATA_DIR \
     --fix-batch-size $FIX_BATCH_SIZE \
     --max-update $TOTAL_UPDATES --log-format simple --log-interval 1 \
     --save-interval-updates $SAVE_INTERVAL_UPDATES \
-    --save-dir $LOG_DIR --ddp-backend=no_c10d
+    --save-dir "$LOG_DIR" --ddp-backend=no_c10d
diff --git a/doc/tools/install-prometheus-server.sh b/doc/tools/install-prometheus-server.sh
index 71db6fd2f..9adfbd561 100755
--- a/doc/tools/install-prometheus-server.sh
+++ b/doc/tools/install-prometheus-server.sh
@@ -5,7 +5,7 @@ set -e
 
 TOOLS_DIR=$(cd "$(dirname "${BASH_SOURCE:-$0}")"; pwd)
 
-pushd $TOOLS_DIR
+pushd "$TOOLS_DIR"
 
 # Download Prometheus server.
 unamestr="$(uname)"
diff --git a/java/generate_jni_header_files.sh b/java/generate_jni_header_files.sh
index 618bc4571..ab0513f07 100755
--- a/java/generate_jni_header_files.sh
+++ b/java/generate_jni_header_files.sh
@@ -10,10 +10,10 @@ cd "$(dirname "$0")"
 function generate_one()
 {
   file=${1//./_}.h
-  javah -classpath ../bazel-bin/java/all_tests_deploy.jar $1
-  clang-format -i $file
+  javah -classpath ../bazel-bin/java/all_tests_deploy.jar "$1"
+  clang-format -i "$file"
 
-  cat <<EOF > ../src/ray/core_worker/lib/java/$file
+  cat <<EOF > ../src/ray/core_worker/lib/java/"$file"
 // Copyright 2017 The Ray Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
@@ -29,8 +29,8 @@ function generate_one()
 // limitations under the License.
 
 EOF
-  cat $file >> ../src/ray/core_worker/lib/java/$file
-  rm -f $file
+  cat "$file" >> ../src/ray/core_worker/lib/java/"$file"
+  rm -f "$file"
 }
 
 generate_one io.ray.runtime.RayNativeRuntime
diff --git a/java/test.sh b/java/test.sh
index 30c305993..088fef546 100755
--- a/java/test.sh
+++ b/java/test.sh
@@ -20,7 +20,7 @@ run_testng() {
     fi
 }
 
-pushd $ROOT_DIR/..
+pushd "$ROOT_DIR"/..
 echo "Linting Java code with checkstyle."
 # NOTE(hchen): The `test_tag_filters` option causes bazel to ignore caches.
 # Thus, we add the `build_tests_only` option to avoid re-building everything.
@@ -36,15 +36,15 @@ echo "Running tests under cluster mode."
 # TODO(hchen): Ideally, we should use the following bazel command to run Java tests. However, if there're skipped tests,
 # TestNG will exit with code 2. And bazel treats it as test failure.
 # bazel test //java:all_tests --action_env=ENABLE_MULTI_LANGUAGE_TESTS=1 --test_output="errors" || cluster_exit_code=$?
-ENABLE_MULTI_LANGUAGE_TESTS=1 run_testng java -cp $ROOT_DIR/../bazel-bin/java/all_tests_deploy.jar org.testng.TestNG -d /tmp/ray_java_test_output $ROOT_DIR/testng.xml
+ENABLE_MULTI_LANGUAGE_TESTS=1 run_testng java -cp "$ROOT_DIR"/../bazel-bin/java/all_tests_deploy.jar org.testng.TestNG -d /tmp/ray_java_test_output "$ROOT_DIR"/testng.xml
 
 echo "Running tests under single-process mode."
 # bazel test //java:all_tests --jvmopt="-Dray.run-mode=SINGLE_PROCESS" --test_output="errors" || single_exit_code=$?
-run_testng java -Dray.run-mode="SINGLE_PROCESS" -cp $ROOT_DIR/../bazel-bin/java/all_tests_deploy.jar org.testng.TestNG -d /tmp/ray_java_test_output $ROOT_DIR/testng.xml
+run_testng java -Dray.run-mode="SINGLE_PROCESS" -cp "$ROOT_DIR"/../bazel-bin/java/all_tests_deploy.jar org.testng.TestNG -d /tmp/ray_java_test_output "$ROOT_DIR"/testng.xml
 
 popd
 
-pushd $ROOT_DIR
+pushd "$ROOT_DIR"
 echo "Testing maven install."
 mvn -Dorg.slf4j.simpleLogger.defaultLogLevel=WARN clean install -DskipTests
 # Ensure mvn test works
diff --git a/python/build-wheel-macos.sh b/python/build-wheel-macos.sh
index 17ef828ee..eca1f60f9 100755
--- a/python/build-wheel-macos.sh
+++ b/python/build-wheel-macos.sh
@@ -39,7 +39,7 @@ mkdir -p $DOWNLOAD_DIR
 mkdir -p .whl
 
 # Use the latest version of Node.js in order to build the dashboard.
-source $HOME/.nvm/nvm.sh
+source "$HOME"/.nvm/nvm.sh
 nvm use node
 
 # Build the dashboard so its static assets can be included in the wheel.
@@ -61,11 +61,11 @@ for ((i=0; i<${#PY_VERSIONS[@]}; ++i)); do
 
   # Install Python.
   INST_PATH=python_downloads/$PY_INST
-  curl $MACPYTHON_URL/$PY_VERSION/$PY_INST > $INST_PATH
-  sudo installer -pkg $INST_PATH -target /
+  curl $MACPYTHON_URL/"$PY_VERSION"/"$PY_INST" > "$INST_PATH"
+  sudo installer -pkg "$INST_PATH" -target /
 
   PYTHON_EXE=$MACPYTHON_PY_PREFIX/$PY_MM/bin/python$PY_MM
-  PIP_CMD="$(dirname $PYTHON_EXE)/pip$PY_MM"
+  PIP_CMD="$(dirname "$PYTHON_EXE")/pip$PY_MM"
 
   pushd /tmp
     # Install latest version of pip to avoid brownouts.
@@ -80,7 +80,7 @@ for ((i=0; i<${#PY_VERSIONS[@]}; ++i)); do
     $PIP_CMD install -q setuptools_scm==3.1.0
     # Fix the numpy version because this will be the oldest numpy version we can
     # support.
-    $PIP_CMD install -q numpy==$NUMPY_VERSION cython==0.29.15
+    $PIP_CMD install -q numpy=="$NUMPY_VERSION" cython==0.29.15
     # Install wheel to avoid the error "invalid command 'bdist_wheel'".
     $PIP_CMD install -q wheel
     # Set the commit SHA in __init__.py.
diff --git a/python/build-wheel-manylinux1.sh b/python/build-wheel-manylinux1.sh
index 3579a04af..1b5bb8c60 100755
--- a/python/build-wheel-manylinux1.sh
+++ b/python/build-wheel-manylinux1.sh
@@ -32,7 +32,7 @@ export PATH=$PATH:/root/bin
 # Install and use the latest version of Node.js in order to build the dashboard.
 set +x
 curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.34.0/install.sh | bash
-source $HOME/.nvm/nvm.sh
+source "$HOME"/.nvm/nvm.sh
 nvm install node
 nvm use node
 
@@ -57,7 +57,7 @@ for ((i=0; i<${#PYTHONS[@]}; ++i)); do
   pushd python
     # Fix the numpy version because this will be the oldest numpy version we can
     # support.
-    /opt/python/${PYTHON}/bin/pip install -q numpy==${NUMPY_VERSION} cython==0.29.15
+    /opt/python/"${PYTHON}"/bin/pip install -q numpy=="${NUMPY_VERSION}" cython==0.29.15
     # Set the commit SHA in __init__.py.
     if [ -n "$TRAVIS_COMMIT" ]; then
       sed -i.bak "s/{{RAY_COMMIT_SHA}}/$TRAVIS_COMMIT/g" ray/__init__.py && rm ray/__init__.py.bak
@@ -66,7 +66,7 @@ for ((i=0; i<${#PYTHONS[@]}; ++i)); do
       exit 1
     fi
 
-    PATH=/opt/python/${PYTHON}/bin:$PATH /opt/python/${PYTHON}/bin/python setup.py bdist_wheel
+    PATH=/opt/python/${PYTHON}/bin:$PATH /opt/python/"${PYTHON}"/bin/python setup.py bdist_wheel
     # In the future, run auditwheel here.
     mv dist/*.whl ../.whl/
   popd
diff --git a/python/ray/autoscaler/kubernetes/kubectl-rsync.sh b/python/ray/autoscaler/kubernetes/kubectl-rsync.sh
index eb756c2d7..583da4ad1 100755
--- a/python/ray/autoscaler/kubernetes/kubectl-rsync.sh
+++ b/python/ray/autoscaler/kubernetes/kubectl-rsync.sh
@@ -6,7 +6,7 @@
 
 if [ -z "$KRSYNC_STARTED" ]; then
     export KRSYNC_STARTED=true
-    exec rsync --blocking-io --rsh "$0" $@
+    exec rsync --blocking-io --rsh "$0" "$@"
 fi
 
 # Running as --rsh
@@ -22,4 +22,4 @@ if [ "X$pod" = "X-l" ]; then
     shift
 fi
 
-exec kubectl $namespace exec -i $pod -- "$@"
+exec kubectl "$namespace" exec -i "$pod" -- "$@"
diff --git a/setup_hooks.sh b/setup_hooks.sh
index 105597f01..9aa0cb0be 100755
--- a/setup_hooks.sh
+++ b/setup_hooks.sh
@@ -1,3 +1,3 @@
 #!/bin/bash
-chmod +x $PWD/scripts/pre-push
-ln -s $PWD/scripts/pre-push $PWD/.git/hooks/pre-push
+chmod +x "$PWD"/scripts/pre-push
+ln -s "$PWD"/scripts/pre-push "$PWD"/.git/hooks/pre-push
diff --git a/src/ray/test/run_object_manager_tests.sh b/src/ray/test/run_object_manager_tests.sh
index b6b0730bd..641c53050 100755
--- a/src/ray/test/run_object_manager_tests.sh
+++ b/src/ray/test/run_object_manager_tests.sh
@@ -9,10 +9,10 @@ set -x
 bazel build "//:object_manager_stress_test" "//:object_manager_test" "//:plasma_store_server"
 
 # Get the directory in which this script is executing.
-SCRIPT_DIR="`dirname \"$0\"`"
+SCRIPT_DIR="$(dirname "$0")"
 RAY_ROOT="$SCRIPT_DIR/../../.."
 # Makes $RAY_ROOT an absolute path.
-RAY_ROOT="`( cd \"$RAY_ROOT\" && pwd )`"
+RAY_ROOT="$(cd "$RAY_ROOT" && pwd)"
 if [ -z "$RAY_ROOT" ] ; then
   exit 1
 fi
@@ -23,13 +23,13 @@ if [ ! -d "$RAY_ROOT/python" ]; then
 fi
 
 REDIS_MODULE="./bazel-bin/libray_redis_module.so"
-LOAD_MODULE_ARGS="--loadmodule ${REDIS_MODULE}"
+LOAD_MODULE_ARGS=(--loadmodule "${REDIS_MODULE}")
 STORE_EXEC="./bazel-bin/plasma_store_server"
 
 # Allow cleanup commands to fail.
 bazel run //:redis-cli -- -p 6379 shutdown || true
 sleep 1s
-bazel run //:redis-server -- --loglevel warning ${LOAD_MODULE_ARGS} --port 6379 &
+bazel run //:redis-server -- --loglevel warning "${LOAD_MODULE_ARGS[@]}" --port 6379 &
 sleep 1s
 # Run tests.
 ./bazel-bin/object_manager_stress_test $STORE_EXEC
diff --git a/src/ray/test/run_object_manager_valgrind.sh b/src/ray/test/run_object_manager_valgrind.sh
index 32c6e8340..7a269eb78 100755
--- a/src/ray/test/run_object_manager_valgrind.sh
+++ b/src/ray/test/run_object_manager_valgrind.sh
@@ -9,10 +9,10 @@ set -x
 bazel build "//:object_manager_stress_test" "//:object_manager_test" "//:plasma_store_server"
 
 # Get the directory in which this script is executing.
-SCRIPT_DIR="`dirname \"$0\"`"
+SCRIPT_DIR="$(dirname "$0")"
 RAY_ROOT="$SCRIPT_DIR/../../.."
 # Makes $RAY_ROOT an absolute path.
-RAY_ROOT="`( cd \"$RAY_ROOT\" && pwd )`"
+RAY_ROOT="$(cd "$RAY_ROOT" && pwd)"
 if [ -z "$RAY_ROOT" ] ; then
   exit 1
 fi
@@ -23,7 +23,7 @@ if [ ! -d "$RAY_ROOT/python" ]; then
 fi
 
 REDIS_MODULE="./bazel-bin/libray_redis_module.so"
-LOAD_MODULE_ARGS="--loadmodule ${REDIS_MODULE}"
+LOAD_MODULE_ARGS=(--loadmodule "${REDIS_MODULE}")
 STORE_EXEC="./bazel-bin/plasma_store_server"
 
 VALGRIND_CMD="valgrind --track-origins=yes --leak-check=full --show-leak-kinds=all --leak-check-heuristics=stdstring --error-exitcode=1"
@@ -32,7 +32,7 @@ VALGRIND_CMD="valgrind --track-origins=yes --leak-check=full --show-leak-kinds=a
 killall plasma_store || true
 bazel run //:redis-cli -- -p 6379 shutdown || true
 sleep 1s
-bazel run //:redis-server -- --loglevel warning ${LOAD_MODULE_ARGS} --port 6379 &
+bazel run //:redis-server -- --loglevel warning "${LOAD_MODULE_ARGS[@]}" --port 6379 &
 sleep 1s
 
 # Run tests. Use timeout=10000ms for the Wait tests since tests run slower
diff --git a/streaming/src/test/run_streaming_queue_test.sh b/streaming/src/test/run_streaming_queue_test.sh
index 8ba7d5bd4..c53e6295f 100755
--- a/streaming/src/test/run_streaming_queue_test.sh
+++ b/streaming/src/test/run_streaming_queue_test.sh
@@ -7,8 +7,7 @@
 PORTS="2000 2001 2002 2003 2004 2005 2006 2007 2008 2009"
 RAYLET_PORT=0
 for port in $PORTS; do
-    nc -z localhost $port
-    if [[ $? != 0 ]]; then
+    if ! nc -z localhost "$port"; then
         RAYLET_PORT=$port
         break
     fi
@@ -24,13 +23,13 @@ set -e
 set -x
 
 # Get the directory in which this script is executing.
-SCRIPT_DIR="`dirname \"$0\"`"
+SCRIPT_DIR="$(dirname "$0")"
 
 # Get the directory in which this script is executing.
-SCRIPT_DIR="`dirname \"$0\"`"
+SCRIPT_DIR="$(dirname "$0")"
 RAY_ROOT="$SCRIPT_DIR/../../.."
 # Makes $RAY_ROOT an absolute path.
-RAY_ROOT="`( cd \"$RAY_ROOT\" && pwd )`"
+RAY_ROOT="$(cd "$RAY_ROOT" && pwd)"
 if [ -z "$RAY_ROOT" ] ; then
   exit 1
 fi
@@ -55,5 +54,5 @@ GCS_SERVER_EXEC="./bazel-bin/gcs_server"
 
 # Allow cleanup commands to fail.
 # Run tests.
-./bazel-bin/streaming/streaming_queue_tests $STORE_EXEC $RAYLET_EXEC $RAYLET_PORT $STREAMING_TEST_WORKER_EXEC $GCS_SERVER_EXEC $REDIS_SERVER_EXEC $REDIS_MODULE $REDIS_CLIENT_EXEC
+./bazel-bin/streaming/streaming_queue_tests $STORE_EXEC $RAYLET_EXEC "$RAYLET_PORT" $STREAMING_TEST_WORKER_EXEC $GCS_SERVER_EXEC $REDIS_SERVER_EXEC $REDIS_MODULE $REDIS_CLIENT_EXEC
 sleep 1s