Delete .shellcheckrc (#1947)

* CI: disable Ubuntu 16.04 as it's EOL

https://github.blog/changelog/2021-04-29-github-actions-ubuntu-16-04-lts-virtual-environment-will-be-removed-on-september-20-2021/

* main: lint false positive

* install: lint

* plugins/cmd-returned-notify: don't `export`

* plugins/xterm: lint

* plugins/git: lint

* plugins/goenv: lint

* plugins/alias-completion: lint false positives

* plugins/alias-completion: fix SC2155, SC2154

Declare `locals` at the top of the function

* completion: lint completions using `bash_completion` functions

Match the style of the existing code

* completion/knife: lint false positives

* completion/knife: lint

* completion/sdkman: lint

* completion/composer: lint

* Move `.shellcheckrc` under `themes/`

* lib/theme: fix SC2155, SC2154, SC2034

* lib/colors: don't warn on unused variables

We assign a large number of variables here and they may or may not be used anywhere else, so disable SC2034 for this file (only).

Alsö disable SC2005 as the functions in this file were written before `printf` was invented and have to do some fancy metascripting to get escape sequences interpreted reliably. I’m not smart enough to fix this to use `printf`, so leave it for now.

* themes/agnoster: lint

* themes: disable SC2154 for colors

Each one of these themes will need it’s own fix for SC2154, possibly upstream.

Due to the way themes are, it's entirely normal to have a *lot* of false positives for SC2034. So much so, that I have to admit that it is probably just not worth linting for SC2034 despite my dislike of blanket ignore rules.

* themes: disable SC2154, fix SC2155

Each one of these themes will need it’s own fix for SC2154, possibly upstream.

Due to the way themes are, it's entirely normal to have a *lot* of false positives for SC2034. So much so, that I have to admit that it is probably just not worth linting for SC2034 despite my dislike of blanket ignore rules.

* Delete `.shellcheckrc`

* remove executable bit

themes/90210/90210.theme.bash

@@ -1,4 +1,7 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
+
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"
 SCM_THEME_PROMPT_PREFIX=" |"
@@ -11,7 +14,7 @@ GIT_THEME_PROMPT_SUFFIX="${green}|"
 
 # Nicely formatted terminal prompt
 function prompt_command() {
-	export PS1="\n${bold_black}[${blue}\@${bold_black}]-${bold_black}[${green}\u${yellow}@${green}\h${bold_black}]-${bold_black}[${purple}\w${bold_black}]-$(scm_prompt_info)\n${reset_color}\$ "
+	PS1="\n${bold_black}[${blue}\@${bold_black}]-${bold_black}[${green}\u${yellow}@${green}\h${bold_black}]-${bold_black}[${purple}\w${bold_black}]-$(scm_prompt_info)\n${reset_color}\$ "
 }
 
 safe_append_prompt_command prompt_command

themes/agnoster/agnoster.theme.bash

@@ -1,4 +1,5 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
 # vim: ft=bash ts=2 sw=2 sts=2
 #
 # agnoster's Theme - https://gist.github.com/3712874
@@ -220,7 +221,7 @@ prompt_virtualenv() {
 
 # Context: user@hostname (who am I and where am I)
 prompt_context() {
-	local user=$(whoami)
+	local user="${USER:-${LOGNAME:?}}"
 
 	if [[ $user != "$DEFAULT_USER" || -n $SSH_CLIENT ]]; then
 		prompt_segment black default "$user@\h"

themes/atomic/atomic.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 # Atomic Bash Prompt for Bash-it
 # By lfelipe base on the theme brainy of MunifTanjim

themes/bakke/bakke.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"

themes/barbuk/barbuk.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 # Theme custom glyphs
 SCM_GIT_CHAR_GITLAB=${BARBUK_GITLAB_CHAR:='  '}

themes/base.theme.bash

@@ -1,4 +1,5 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
 
 CLOCK_CHAR_THEME_PROMPT_PREFIX=''
 CLOCK_CHAR_THEME_PROMPT_SUFFIX=''
@@ -130,12 +131,11 @@ function scm {
 }
 
 scm_prompt() {
-	local CHAR=$(scm_char)
+	local CHAR
+	CHAR="$(scm_char)"
 	local format=${SCM_PROMPT_FORMAT:-'[%s%s]'}
 
-	if [[ $CHAR = "$SCM_NONE_CHAR" ]]; then
-		return
-	else
+	if [[ "${CHAR}" != "$SCM_NONE_CHAR" ]]; then
 		# shellcheck disable=2059
 		printf "$format\n" "$CHAR" "$(scm_prompt_info)"
 	fi
@@ -352,15 +352,15 @@ function svn_prompt_vars {
 # - .hg is located in ~/Projects/Foo/.hg
 # - get_hg_root starts at ~/Projects/Foo/Bar and sees that there is no .hg directory, so then it goes into ~/Projects/Foo
 function get_hg_root {
-	local CURRENT_DIR=$(pwd)
+	local CURRENT_DIR="${PWD}"
 
-	while [ "$CURRENT_DIR" != "/" ]; do
-		if [ -d "$CURRENT_DIR/.hg" ]; then
+	while [[ "${CURRENT_DIR:-/}" != "/" ]]; do
+		if [[ -d "$CURRENT_DIR/.hg" ]]; then
 			echo "$CURRENT_DIR/.hg"
 			return
 		fi
 
-		CURRENT_DIR=$(dirname "$CURRENT_DIR")
+		CURRENT_DIR="${CURRENT_DIR%/*}"
 	done
 }
 
@@ -552,7 +552,7 @@ function prompt_char {
 
 function battery_char {
 	if [[ "${THEME_BATTERY_PERCENTAGE_CHECK}" = true ]]; then
-		echo -e "${bold_red}$(battery_percentage)%"
+		echo -e "${bold_red:-}$(battery_percentage)%"
 	fi
 }
 
@@ -594,7 +594,7 @@ function __check_precmd_conflict() {
 function safe_append_prompt_command {
 	local prompt_re
 
-	if [ "${__bp_imported}" == "defined" ]; then
+	if [ "${__bp_imported:-missing}" == "defined" ]; then
 		# We are using bash-preexec
 		if ! __check_precmd_conflict "${1}"; then
 			precmd_functions+=("${1}")
@@ -609,7 +609,7 @@ function safe_append_prompt_command {
 			prompt_re="\<${1}\>"
 		fi
 
-		if [[ ${PROMPT_COMMAND} =~ ${prompt_re} ]]; then
+		if [[ ${PROMPT_COMMAND[*]:-} =~ ${prompt_re} ]]; then
 			return
 		elif [[ -z ${PROMPT_COMMAND} ]]; then
 			PROMPT_COMMAND="${1}"

themes/binaryanomaly/binaryanomaly.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 # Detect whether a reboot is required
 function show_reboot_required() {

themes/bira/bira.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_PREFIX=" ${yellow}‹"
 SCM_THEME_PROMPT_SUFFIX="›${reset_color}"

themes/bobby-python/bobby-python.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"

themes/bobby/bobby.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"

themes/brainy/brainy.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 # Brainy Bash Prompt for Bash-it
 # by MunifTanjim

themes/brunton/brunton.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_PREFIX=""
 SCM_THEME_PROMPT_SUFFIX=""

themes/candy/candy.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 function prompt_command() {
 	PS1="${green}\u@\h $(clock_prompt) ${reset_color}${white}\w${reset_color}$(scm_prompt_info)${blue} →${bold_blue} ${reset_color} ${normal}"

themes/colors.theme.bash

@@ -1,4 +1,6 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
+# shellcheck disable=SC2005
+# shellcheck disable=SC2034
 
 function __ {
   echo "$@"

themes/easy/easy.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_PREFIX="${bold_green}[ ${normal}"
 SCM_THEME_PROMPT_SUFFIX="${bold_green} ] "

themes/modern/modern.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_PREFIX=""
 SCM_THEME_PROMPT_SUFFIX=""

themes/powerline/powerline.base.bash

@@ -1,4 +1,7 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
+
 # Define this here so it can be used by all of the Powerline themes
 THEME_CHECK_SUDO=${THEME_CHECK_SUDO:=true}
 
@@ -139,7 +142,7 @@ function __powerline_scm_prompt() {
 }
 
 function __powerline_cwd_prompt() {
-	local cwd=$(pwd | sed "s|^${HOME}|~|")
+	local cwd="${PWD/$HOME/\~}"
 
 	echo "${cwd}|${CWD_THEME_PROMPT_COLOR}"
 }
@@ -157,10 +160,10 @@ function __powerline_clock_prompt() {
 }
 
 function __powerline_battery_prompt() {
-	local color=""
-	local battery_status="$(battery_percentage 2> /dev/null)"
+	local color="" battery_status
+	battery_status="$(battery_percentage 2> /dev/null)"
 
-	if [[ -z "${battery_status}" ]] || [[ "${battery_status}" = "-1" ]] || [[ "${battery_status}" = "no" ]]; then
+	if [[ -z "${battery_status}" || "${battery_status}" == "-1" || "${battery_status}" == "no" ]]; then
 		true
 	else
 		if [[ "$((10#${battery_status}))" -le 5 ]]; then
@@ -176,7 +179,7 @@ function __powerline_battery_prompt() {
 }
 
 function __powerline_in_vim_prompt() {
-	if [ -n "$VIMRUNTIME" ]; then
+	if [[ -n "$VIMRUNTIME" ]]; then
 		echo "${IN_VIM_THEME_PROMPT_TEXT}|${IN_VIM_THEME_PROMPT_COLOR}"
 	fi
 }
@@ -221,7 +224,8 @@ function __powerline_command_number_prompt() {
 }
 
 function __powerline_duration_prompt() {
-	local duration=$(_command_duration)
+	local duration
+	duration=$(_command_duration)
 	[[ -n "$duration" ]] && echo "${duration}|${COMMAND_DURATION_PROMPT_COLOR}"
 }
 
@@ -265,7 +269,7 @@ function __powerline_last_status_prompt() {
 
 function __powerline_prompt_command() {
 	local last_status="$?" ## always the first
-	local separator_char="${POWERLINE_PROMPT_CHAR}"
+	local separator_char="${POWERLINE_PROMPT_CHAR}" info prompt_color
 
 	LEFT_PROMPT=""
 	SEGMENTS_AT_LEFT=0
@@ -277,7 +281,7 @@ function __powerline_prompt_command() {
 
 	## left prompt ##
 	for segment in $POWERLINE_PROMPT; do
-		local info="$(__powerline_"${segment}"_prompt)"
+		info="$(__powerline_"${segment}"_prompt)"
 		[[ -n "${info}" ]] && __powerline_left_segment "${info}"
 	done
 
@@ -289,7 +293,7 @@ function __powerline_prompt_command() {
 
 	# By default we try to match the prompt to the adjacent segment's background color,
 	# but when part of the prompt exists within that segment, we instead match the foreground color.
-	local prompt_color="$(set_color "${LAST_SEGMENT_COLOR}" -)"
+	prompt_color="$(set_color "${LAST_SEGMENT_COLOR}" -)"
 	if [[ -n "${LEFT_PROMPT}" ]] && [[ -n "${POWERLINE_LEFT_LAST_SEGMENT_PROMPT_CHAR}" ]]; then
 		LEFT_PROMPT+="$(set_color - "${LAST_SEGMENT_COLOR}")${POWERLINE_LEFT_LAST_SEGMENT_PROMPT_CHAR}"
 		prompt_color="${normal}"

themes/powerline/powerline.theme.bash

@@ -1,4 +1,5 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
 
 # shellcheck source=../../themes/powerline/powerline.base.bash
 . "$BASH_IT/themes/powerline/powerline.base.bash"

themes/pure/pure.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 # scm theming
 SCM_THEME_PROMPT_PREFIX="|"

themes/purity/purity.theme.bash

@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_DIRTY=" ${bold_red}⊘${normal}"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓${normal}"
@@ -26,8 +28,8 @@ venv_prompt() {
 }
 
 function prompt_command() {
-	retval=$?
-	local ret_status="$([ $retval -eq 0 ] && echo -e "$STATUS_THEME_PROMPT_OK" || echo -e "$STATUS_THEME_PROMPT_BAD")"
+	local retval=$? ret_status
+	ret_status="$([ $retval -eq 0 ] && echo -e "$STATUS_THEME_PROMPT_OK" || echo -e "$STATUS_THEME_PROMPT_BAD")"
 	PS1="\n${PURITY_THEME_PROMPT_COLOR}\w $(scm_prompt_info)\n${ret_status}$(venv_prompt)"
 }