Fix shellcheck warnings: Escaping.

```
build:3:65: note: Backslash is literal in "\n". Prefer explicit escaping: "\\n". [SC1117]
test:3:64: note: Backslash is literal in "\n". Prefer explicit escaping: "\\n". [SC1117]
scripts/fix.sh:23:17: note: Backslash is literal in "\n". Prefer explicit escaping: "\\n". [SC1117]
scripts/fix.sh:23:46: note: Backslash is literal in "\n". Prefer explicit escaping: "\\n". [SC1117]
scripts/fix.sh:30:17: note: Backslash is literal in "\n". Prefer explicit escaping: "\\n". [SC1117]
scripts/genproto.sh:38:17: note: Backslash is literal in "\n". Prefer explicit escaping: "\\n". [SC1117]
scripts/genproto.sh:53:17: note: Backslash is literal in "\n". Prefer explicit escaping: "\\n". [SC1117]
scripts/genproto.sh:73:23: note: Backslash is literal in "\(". Prefer explicit escaping: "\\(". [SC1117]
scripts/genproto.sh:73:33: note: Backslash is literal in "\(". Prefer explicit escaping: "\\(". [SC1117]
scripts/genproto.sh:74:69: note: Backslash is literal in "\1". Prefer explicit escaping: "\\1". [SC1117]
scripts/genproto.sh:74:78: note: Backslash is literal in "\2". Prefer explicit escaping: "\\2". [SC1117]
scripts/genproto.sh:75:40: note: Backslash is literal in "\(". Prefer explicit escaping: "\\(". [SC1117]
scripts/genproto.sh:75:52: note: Backslash is literal in "\1". Prefer explicit escaping: "\\1". [SC1117]
scripts/genproto.sh:91:17: note: Backslash is literal in "\n". Prefer explicit escaping: "\\n". [SC1117]
scripts/genproto.sh:115:17: note: Backslash is literal in "\n". Prefer explicit escaping: "\\n". [SC1117]
./test.sh:71:29: warning: Quote to prevent word splitting, or split robustly with mapfile or read -a. [SC2206]
./test.sh:400:28: note: Backslash is literal in "\t". Prefer explicit escaping: "\\t". [SC1117]
./test.sh:406:33: note: Backslash is literal in "\t". Prefer explicit escaping: "\\t". [SC1117]
./test.sh:415:36: note: Backslash is literal in "\*". Prefer explicit escaping: "\\*". [SC1117]
./test.sh:415:176: note: Backslash is literal in "\'". Prefer explicit escaping: "\\'". [SC1117]
./test.sh:493:56: note: Backslash is literal in "\.". Prefer explicit escaping: "\\.". [SC1117]
./test.sh:601:57: note: Backslash is literal in "\(". Prefer explicit escaping: "\\(". [SC1117]
./test.sh:601:64: note: Backslash is literal in "\)". Prefer explicit escaping: "\\)". [SC1117]
./test.sh:601:67: note: Backslash is literal in "\(". Prefer explicit escaping: "\\(". [SC1117]
./test.sh:601:74: note: Backslash is literal in "\)". Prefer explicit escaping: "\\)". [SC1117]
./test.sh:601:77: note: Backslash is literal in "\(". Prefer explicit escaping: "\\(". [SC1117]
./test.sh:601:84: note: Backslash is literal in "\)". Prefer explicit escaping: "\\)". [SC1117]
./test.sh:601:91: note: Backslash is literal in "\1". Prefer explicit escaping: "\\1". [SC1117]
./test.sh:601:94: note: Backslash is literal in "\2". Prefer explicit escaping: "\\2". [SC1117]
./test.sh:601:103: note: Backslash is literal in "\3". Prefer explicit escaping: "\\3". [SC1117]
```

build

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-echo -e "\e[91mDEPRECATED!!! Use build.sh script instead.\e[0m\n"
+echo -e "\\e[91mDEPRECATED!!! Use build.sh script instead.\\e[0m\\n"
 sleep 1
 
 source ./build.sh

scripts/fix.sh

@@ -20,11 +20,11 @@ function bash_ws_fix {
   find ./ -name '*.sh.bak' -print0 | xargs -0 rm
 }
 
-log_callout -e "\nFixing etcd code for you...\n"
+log_callout -e "\\nFixing etcd code for you...\\n"
 
 run_for_modules run go fmt || exit 2
 run_for_modules mod_tidy_fix || exit 2
 run_for_module tests bom_fix || exit 2
 bash_ws_fix || exit 2
 
-log_success -e "\nSUCCESS: etcd code is fixed :)"
+log_success -e "\\nSUCCESS: etcd code is fixed :)"

scripts/genproto.sh

@@ -35,7 +35,7 @@ GOGOPROTO_PATH="${GOGOPROTO_ROOT}:${GOGOPROTO_ROOT}/protobuf"
 # directories containing protos to be built
 DIRS="./server/wal/walpb ./api/etcdserverpb ./server/etcdserver/api/snap/snappb ./raft/raftpb ./api/mvccpb ./server/lease/leasepb ./api/authpb ./server/etcdserver/api/v3lock/v3lockpb ./server/etcdserver/api/v3election/v3electionpb ./api/membershippb"
 
-log_callout -e "\nRunning gofast (gogo) proto generation..."
+log_callout -e "\\nRunning gofast (gogo) proto generation..."
 
 for dir in ${DIRS}; do
   run pushd "${dir}"
@@ -50,7 +50,7 @@ for dir in ${DIRS}; do
   run popd
 done
 
-log_callout -e "\nRunning swagger & grpc_gateway proto generation..."
+log_callout -e "\\nRunning swagger & grpc_gateway proto generation..."
 
 # remove old swagger files so it's obvious whether the files fail to generate
 rm -rf Documentation/dev-guide/apispec/swagger/*json
@@ -70,9 +70,9 @@ for pb in api/etcdserverpb/rpc server/etcdserver/api/v3lock/v3lockpb/v3lock serv
   gwfile="${pb}.pb.gw.go"
 
   sed -i -E "s#package $pkg#package gw#g" "${gwfile}"
-  sed -i -E "s#import \(#import \(\"go.etcd.io/etcd/${pkgpath}\"#g" "${gwfile}"
+  sed -i -E "s#import \\(#import \\(\"go.etcd.io/etcd/${pkgpath}\"#g" "${gwfile}"
-  sed -i -E "s#([ (])([a-zA-Z0-9_]*(Client|Server|Request)([^(]|$))#\1${pkg}.\2#g" "${gwfile}"
+  sed -i -E "s#([ (])([a-zA-Z0-9_]*(Client|Server|Request)([^(]|$))#\\1${pkg}.\\2#g" "${gwfile}"
-  sed -i -E "s# (New[a-zA-Z0-9_]*Client\()# ${pkg}.\1#g" "${gwfile}"
+  sed -i -E "s# (New[a-zA-Z0-9_]*Client\\()# ${pkg}.\\1#g" "${gwfile}"
   sed -i -E "s|go.etcd.io/etcd|go.etcd.io/etcd/v3|g" "${gwfile}"
   sed -i -E "s|go.etcd.io/etcd/v3/api|go.etcd.io/etcd/api/v3|g" "${gwfile}"
   sed -i -E "s|go.etcd.io/etcd/v3/server|go.etcd.io/etcd/server/v3|g" "${gwfile}"
@@ -88,7 +88,7 @@ for pb in api/etcdserverpb/rpc server/etcdserver/api/v3lock/v3lockpb/v3lock serv
     Documentation/dev-guide/apispec/swagger/"${swaggerName}".swagger.json
 done
 
-log_callout -e "\nRunning swagger ..."
+log_callout -e "\\nRunning swagger ..."
 run_go_tool github.com/hexfusion/schwag -input=Documentation/dev-guide/apispec/swagger/rpc.swagger.json
 
 if [ "$1" != "--skip-protodoc" ]; then
@@ -112,4 +112,4 @@ else
   log_warning "skipping grpc API reference document auto-generation..."
 fi
 
-log_success -e "\n./genproto SUCCESS"
+log_success -e "\\n./genproto SUCCESS"

scripts/test_lib.sh

@@ -146,7 +146,7 @@ function run {
   "${@}" 2> >(while read -r line; do echo -e "${COLOR_NONE}stderr: ${COLOR_MAGENTA}${line}${COLOR_NONE}">&2; done)
   local error_code=$?
   if [ ${error_code} -ne 0 ]; then
-    log_error -e "FAIL: (code:${error_code}):\n  % ${repro}"
+    log_error -e "FAIL: (code:${error_code}):\\n  % ${repro}"
     return ${error_code}
   fi
 }
@@ -170,7 +170,7 @@ function module_dirs() {
 # maybe_run [cmd...] runs given command depending on the DRY_RUN flag.
 function maybe_run() {
   if ${DRY_RUN}; then
-    log_warning -e "# DRY_RUN:\n  % ${*}"
+    log_warning -e "# DRY_RUN:\\n  % ${*}"
   else
     run "${@}"
   fi
@@ -280,7 +280,7 @@ function go_test {
   done
 
   if [ -n "${failures[*]}" ] ; then
-    log_error -e "ERROR: Tests for following packages failed:\n  ${failures[*]}"
+    log_error -e "ERROR: Tests for following packages failed:\\n  ${failures[*]}"
     return 2
   fi
 }

test

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-echo -e "\e[91mDEPRECATED!!! Use test.sh script instead.\e[0m\n"
+echo -e "\\e[91mDEPRECATED!!! Use test.sh script instead.\\e[0m\\n"
 sleep 1
 
 source ./test.sh

test.sh

@@ -68,7 +68,7 @@ fi
 # This options make sense for cases where SUT (System Under Test) is compiled by test.
 COMMON_TEST_FLAGS=("${RACE}")
 if [[ ! -z "${CPU}" ]]; then
-  COMMON_TEST_FLAGS+=(--cpu ${CPU})
+  COMMON_TEST_FLAGS+=("--cpu=${CPU}")
 fi 
 
 log_callout "Running with ${COMMON_TEST_FLAGS[*]}"
@@ -174,13 +174,13 @@ function functional_pass {
   kill -s TERM "${agent_pids[@]}" || true
 
   if [[ "${etcd_tester_exit_code}" -ne "0" ]]; then
-    log_error -e "\nFAILED! 'tail -1000 /tmp/etcd-functional-1/etcd.log'"
+    log_error -e "\\nFAILED! 'tail -1000 /tmp/etcd-functional-1/etcd.log'"
     tail -1000 /tmp/etcd-functional-1/etcd.log
 
-    log_error -e "\nFAILED! 'tail -1000 /tmp/etcd-functional-2/etcd.log'"
+    log_error -e "\\nFAILED! 'tail -1000 /tmp/etcd-functional-2/etcd.log'"
     tail -1000 /tmp/etcd-functional-2/etcd.log
 
-    log_error -e "\nFAILED! 'tail -1000 /tmp/etcd-functional-3/etcd.log'"
+    log_error -e "\\nFAILED! 'tail -1000 /tmp/etcd-functional-3/etcd.log'"
     tail -1000 /tmp/etcd-functional-3/etcd.log
 
     log_error "--- FAIL: exit code" ${etcd_tester_exit_code}
@@ -392,18 +392,19 @@ function shellcheck_pass {
 }
 
 function shellws_pass {
+  TAB=$'\t'
   log_callout "Ensuring no tab-based indention in shell scripts"
   local files
   files=$(find ./ -name '*.sh' -print0 | xargs -0 )
   # shellcheck disable=SC2206
   files=( ${files[@]} "./scripts/build-binary" "./scripts/build-docker" "./scripts/release" )
-  log_cmd "grep -E -n $'^ *\t' ${files[*]}"
+  log_cmd "grep -E -n $'^ *${TAB}' ${files[*]}"
   # shellcheck disable=SC2086
-  if grep -E -n $'^ *\t' "${files[@]}" | sed $'s|\t|[\\\\tab]|g'; then
+  if grep -E -n $'^ *${TAB}' "${files[@]}" | sed $'s|${TAB}|[\\\\tab]|g'; then
     log_error "FAIL: found tab-based indention in bash scripts. Use '  ' (double space)."
     local files_with_tabs
-    files_with_tabs=$(grep -E -l $'^ *\t' "${files[@]}")
+    files_with_tabs=$(grep -E -l $'^ *\\t' "${files[@]}")
-    log_warning "Try: sed -i 's|\t|  |g' $files_with_tabs"
+    log_warning "Try: sed -i 's|\\t|  |g' $files_with_tabs"
     return 1
   else
     log_success "SUCCESS: no tabulators found."
@@ -412,7 +413,7 @@ function shellws_pass {
 }
 
 function markdown_you_find_eschew_you {
-  local find_you_cmd="find . -name \*.md ! -path '*/vendor/*' ! -path './Documentation/*' ! -path './gopath.proto/*' ! -path './release/*' -exec grep -E --color '[Yy]ou[r]?[ '\''.,;]' {} + || true"
+  local find_you_cmd="find . -name \\*.md ! -path '*/vendor/*' ! -path './Documentation/*' ! -path './gopath.proto/*' ! -path './release/*' -exec grep -E --color '[Yy]ou[r]?[ '\\''.,;]' {} + || true"
   run eval "${find_you_cmd}"
 }
 
@@ -490,7 +491,7 @@ function receiver_name_for_package {
   while IFS= read -r line; do gofiles+=("$line"); done < <(go_srcs_in_module "$1")
 
   recvs=$(grep 'func ([^*]' "${gofiles[@]}"  | tr  ':' ' ' |  \
-    awk ' { print $2" "$3" "$4" "$1 }' | sed "s/[a-zA-Z\.]*go//g" |  sort  | uniq  | \
+    awk ' { print $2" "$3" "$4" "$1 }' | sed "s/[a-zA-Z\\.]*go//g" |  sort  | uniq  | \
     grep -Ev  "(Descriptor|Proto|_)"  | awk ' { print $3" "$4 } ' | sort | uniq -c | grep -v ' 1 ' | awk ' { print $2 } ')
   if [ -n "${recvs}" ]; then
     # shellcheck disable=SC2206
@@ -566,7 +567,7 @@ function bom_pass {
   run cp go.mod.tmp go.mod || return 2
 
   if [ "${code}" -ne 0 ] ; then
-    log_error -e "license-bill-of-materials (code: ${code}) failed with:\n${output}"
+    log_error -e "license-bill-of-materials (code: ${code}) failed with:\\n${output}"
     return 255
   else
     echo "${output}" > "bom-now.json.tmp"
@@ -598,7 +599,7 @@ function dep_pass {
 
   for dup in ${duplicates}; do
     log_error "FAIL: inconsistent versions for depencency: ${dup}"
-    echo "${all_dependencies}" | grep "${dup}" | sed "s|\([^,]*\),\([^,]*\),\([^,]*\)|  - \1@\2 from: \3|g"
+    echo "${all_dependencies}" | grep "${dup}" | sed "s|\\([^,]*\\),\\([^,]*\\),\\([^,]*\\)|  - \\1@\\2 from: \\3|g"
   done
   if [[ -n "${duplicates}" ]]; then
     log_error "FAIL: inconsistent dependencies"
@@ -685,7 +686,7 @@ function mod_tidy_pass {
 function run_pass {
   local pass="${1}"
   shift 1
-  log_callout -e "\n'${pass}' started at $(date)"
+  log_callout -e "\\n'${pass}' started at $(date)"
   if "${pass}_pass" "$@" ; then
     log_success "'${pass}' completed at $(date)"
   else