Rework of shell ci

Bug fixes:
* ci now checks only shell scripts

New features:
* add ability to ignore specific warnings
* ci test files containing shebang #!/bin/bash or #!/bin/sh
* ci test files with .sh extension
* add ability to use inline comments in list files
* use of colors in output
* make code cleaner

4 files changed, 134 insertions, 23 deletions

diff --git a/.ci/check-shell.sh b/.ci/check-shell.sh
index a4ea3c52..6fef7dd1 100755
--- a/.ci/check-shell.sh
+++ b/.ci/check-shell.sh
@@ -1,5 +1,6 @@
 #!/bin/bash
 
+# Path is wrong because of travis
 . ./.ci/functions.sh
 
 # ------------ #
@@ -8,63 +9,84 @@
 
 # https://medium.com/@joey_9999/how-to-only-lint-files-a-git-pull-request-modifies-3f02254ec5e0
 # get names of files from PR (excluding deleted files)
-# TRAVIS_COMMIT_RANGE - HEAD of destination branch ... HEAD of PR branch
 git diff --name-only --diff-filter=db "${TRAVIS_COMMIT_RANGE}" > ../pr-changes.txt
 
 # Find modified shell scripts
-readarray list_of_changes < <(grep "^[^#]" ../pr-changes.txt)
+list_of_changes=()
+file_to_array "../pr-changes.txt" "list_of_changes" 0
+list_of_scripts=()
+file_to_array "./.ci/script-list.txt" "list_of_scripts" 1
+
+# Create list of scripts for testing
 list_of_changed_scripts=()
 for file in "${list_of_changes[@]}"; do
-  # https://stackoverflow.com/questions/19345872/how-to-remove-a-newline-from-a-string-in-bash
-  # Remove new line and add ./ at the beginning
-  is_it_script "$file" && list_of_changed_scripts+=("./${file//[$'\t\r\n ']}")
+  is_it_script "$file" "${list_of_scripts[@]}" && list_of_changed_scripts+=("./${file}") && continue
+  check_extension "$file" && list_of_changed_scripts+=("./${file}") && continue
+  check_shebang "$file" && list_of_changed_scripts+=("./${file}")
 done
 
-echo "Changed shell scripts:"
+# Get list of exceptions
+list_of_exceptions=()
+file_to_array "./.ci/exception-list.txt" "list_of_exceptions" 1
+string_of_exceptions=$(join_by , "${list_of_exceptions[@]}")
+
+echo -e "\n"
+echo ":::::::::::::::::::::"
+echo -e "::: ${WHITE}Shellcheck CI${NOCOLOR} :::"
+echo ":::::::::::::::::::::"
+echo -e "\n"
+
+echo -e "${WHITE}Changed shell scripts:${NOCOLOR}"
 echo "${list_of_changed_scripts[@]}"
-echo "------------"
+echo -e "${WHITE}List of shellcheck exceptions:${NOCOLOR}"
+echo "${string_of_exceptions}"
+echo -e "\n"
 
 # ------------ #
 #  SHELLCHECK  #
 # ------------ #
 
 # sed part is to edit shellcheck output so csdiff/csgrep knows it is shellcheck output (--format=gcc)
-shellcheck --format=gcc "${list_of_changed_scripts[@]}" | sed -e 's|$| <--[shellcheck]|' > ../pr-br-shellcheck.err
+shellcheck --format=gcc --exclude="${string_of_exceptions}" "${list_of_changed_scripts[@]}" 2> /dev/null | sed -e 's|$| <--[shellcheck]|' > ../pr-br-shellcheck.err
 
 # make destination branch
-[[ ${TRAVIS_COMMIT_RANGE} =~ ^([0-9|a-f]*?)\. ]] && git checkout -b ci_br_dest "${BASH_REMATCH[1]}"
+[[ ${TRAVIS_COMMIT_RANGE} =~ ^([0-9|a-f]*?)\. ]] && git checkout -q -b ci_br_dest "${BASH_REMATCH[1]}"
 
-shellcheck --format=gcc "${list_of_changed_scripts[@]}" | sed -e 's|$| <--[shellcheck]|' > ../dest-br-shellcheck.err
+shellcheck --format=gcc --exclude="${string_of_exceptions}" "${list_of_changed_scripts[@]}" 2> /dev/null | sed -e 's|$| <--[shellcheck]|' > ../dest-br-shellcheck.err
 
 # ------------ #
 #  VALIDATION  #
 # ------------ #
 
 exitstatus=0
+echo ":::::::::::::::::::::::::"
+echo -e "::: ${WHITE}Validation Output${NOCOLOR} :::"
+echo ":::::::::::::::::::::::::"
+echo -e "\n"
 
 # Check output for Fixes
 csdiff --fixed "../dest-br-shellcheck.err" "../pr-br-shellcheck.err" > ../fixes.log
 if [ "$(cat ../fixes.log | wc -l)" -ne 0 ]; then
-  echo "Fixed bugs:" 
+  echo -e "${GREEN}Fixed bugs:${NOCOLOR}" 
   csgrep ../fixes.log
-  echo "------------"
+  echo "---------------------"
 else
-  echo "No Fixes!"
-  echo "------------"
+  echo -e "${YELLOW}No Fixes!${NOCOLOR}"
+  echo "---------------------"
 fi
+echo -e "\n"
 
 # Check output for added bugs
 csdiff --fixed "../pr-br-shellcheck.err" "../dest-br-shellcheck.err" > ../bugs.log
 if [ "$(cat ../bugs.log | wc -l)" -ne 0 ]; then
-  echo "Added bugs, NEED INSPECTION:" 
+  echo -e "${RED}Added bugs, NEED INSPECTION:${NOCOLOR}" 
   csgrep ../bugs.log
-  echo "------------"
+  echo "---------------------"
   exitstatus=1
 else
-  echo "No bugs added Yay!" 
-  echo "------------"
+  echo -e "${GREEN}No bugs added Yay!${NOCOLOR}" 
+  echo "---------------------"
   exitstatus=0
 fi
 
 exit $exitstatus
-
diff --git a/.ci/exception-list.txt b/.ci/exception-list.txt
new file mode 100644
index 00000000..5b093820
--- /dev/null
+++ b/.ci/exception-list.txt
@@ -0,0 +1,4 @@
+# List of Shelcheck codes which should be excluded from ci output
+# Avoid spaces in list since they are counted as comment
+SC1090    # Ignore when shellcheck can't follow non-constant source e.g. ``. "${path}"``
+SC2148    # Ignore missing shebang
diff --git a/.ci/functions.sh b/.ci/functions.sh
index 300f92df..cbe00874 100644
--- a/.ci/functions.sh
+++ b/.ci/functions.sh
@@ -1,9 +1,92 @@
 # Function to check whether input param is on list of shell scripts
 # $1 - <string> absolute path to file
+# $@ - <array of strings> list of strings to compare with
+# $? - return value - 0 when succes
 is_it_script () {
-  [ $# -eq 0 ] && return 1
-  
-  readarray list_of_scripts < ./.ci/script-list.txt
-  echo "${list_of_scripts[@]}" | grep --silent "$1" && return 0
+  [ $# -le 1 ] && return 1
+  local file="$1"
+  shift
+  local scripts=("$@")
+
+  [[ " ${scripts[*]} " =~ " ${file} " ]] && return 0 || return 2
+}
+
+# Function to check if given file has .sh extension
+# https://stackoverflow.com/a/407229
+# $1 - <string> absolute path to file
+# $? - return value - 0 when succes
+check_extension () {
+  [ $# -le 0 ] && return 1
+  local file="$1"
+
+  [ "${file: -3}" == ".sh" ] && return 0 || return 2
+}
+
+# Function to check if given file contain shell shebang (bash or sh)
+# https://unix.stackexchange.com/a/406939
+# $1 - <string> absolute path to file
+# $? - return value - 0 when succes
+check_shebang () {
+  [ $# -le 0 ] && return 1
+  local file="$1"
+
+  if IFS= read -r line < "./${file}" ; then
+    case $line in
+      "#!/bin/bash") return 0;;
+      "#!/bin/sh") return 0;;
+      *) return 1
+    esac
+  fi
+}
+
+# Function to prepare string from array of strings where first argument specify one character separator
+# https://stackoverflow.com/a/17841619
+# $1 - <char> Character used to join elements of array
+# $@ - <array of string> list of strings
+# return value - string
+join_by () {
+  local IFS="$1"
+  shift
+  echo "$*"
+}
+
+# Function to get rid of comments represented by '#'
+# $1 - file path
+# $2 - name of variable where will be stored result array
+# $3 - value 1|0 - does file content inline comments?
+# $? - return value - 0 when succes
+file_to_array () {
+  [ $# -le 2 ] && return 1
+  local output=()
+
+  [ "$3" -eq 0 ] && readarray output < <(grep -v "^#.*" "$1")                         # fetch array with lines from file while excluding '#' comments  
+  [ "$3" -eq 1 ] && readarray output < <(cut -d ' ' -f 1 < <(grep -v "^#.*" "$1"))    # fetch array with lines from file while excluding '#' comments
+  clean_array "$2" "${output[@]}" && return 0
+}
+
+# Function to get rid of spaces and new lines from array elements
+# https://stackoverflow.com/a/9715377
+# https://stackoverflow.com/a/19347380
+# https://unix.stackexchange.com/a/225517
+# $1 - name of variable where will be stored result array
+# $@ - source array
+# $? - return value - 0 when succes
+clean_array () {
+  [ $# -le 2 ] && return 1
+  local output="$1"
+  shift
+  local input=("$@")
+
+  for i in "${input[@]}"; do
+    eval $output+=\("${i//[$'\t\r\n ']}"\)
+  done
 }
 
+# Color aliases use echo -e to use them
+NOCOLOR='\033[0m'
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+ORANGE='\033[0;33m'
+BLUE='\033[0;34m'
+YELLOW='\033[1;33m'
+WHITE='\033[1;37m'
diff --git a/.ci/script-list.txt b/.ci/script-list.txt
index 7323ceb7..053672df 100644
--- a/.ci/script-list.txt
+++ b/.ci/script-list.txt
@@ -1,4 +1,6 @@
 # Tracker of all shell scripts in this repository
+# Every new script should be added in order to test it with ci
+# Avoid spaces in list since they are counted as comment
 etc/rc.d/init.d/functions
 etc/rc.d/init.d/network
 network-scripts/ifdown-bnep