Fix most of the errors and warnings reported by shellcheck

build.sh

@@ -75,7 +75,8 @@ step_preprocess() {
 
 		# Replace the DOCS_* variables.
 		if [[ "$line" =~ ^DOCS_[A-Z]+=.*$ ]]; then
-			local docvar="$(cut -d'=' -f1 <<<"$line")"
+			local docvar
+			docvar="$(cut -d'=' -f1 <<<"$line")"
 			printf "%s=%q\n" "$docvar" "${!docvar}"
 			continue
 		fi
@@ -83,13 +84,13 @@ step_preprocess() {
 		# Embed library scripts.
 		if [[ "$line" =~ ^[[:space:]]*source[[:space:]]+[\"\']\$\{?LIB\}/([a-z_-]+\.sh)[\"\'] ]]; then
 			echo "# --- BEGIN LIBRARY FILE: ${BASH_REMATCH[1]} ---"
-			cat "$LIB/${BASH_REMATCH[1]}" | {
+			{
 				if [[ "$OPT_MINIFY" = "lib" ]]; then
 					pp_strip_comments | pp_minify | pp_minify_unsafe
 				else
 					cat
 				fi
-			}
+			} <"$LIB/${BASH_REMATCH[1]}"
 			echo "# --- END LIBRARY FILE ---"
 			continue
 		fi
@@ -136,7 +137,8 @@ step_compress() {
 		return 0
 	fi
 
-	local wrapper="$({
+	local wrapper
+	wrapper="$({
 		printf '#!/usr/bin/env bash\n'
 		printf "(exec -a \"\$0\" bash -c 'eval \"\$(cat <&3)\"' \"\$0\" \"\$@\" 3< <(dd bs=1 if=\"\$0\" skip=::: 2>/dev/null | gunzip)); exit \$?;\n"
 	})"

lib/pager.sh

@@ -22,7 +22,8 @@ is_pager_disabled() {
 pager_name() {
 	if [[ -z "${SCRIPT_PAGER_CMD[0]}" ]]; then return; fi
 	if [[ -z "$_SCRIPT_PAGER_NAME" ]]; then
-		local output="$("${SCRIPT_PAGER_CMD[0]}" --version 2>&1)"
+		local output
+		output="$("${SCRIPT_PAGER_CMD[0]}" --version 2>&1)"
 
 		if head -n 1 <<<"$output" | grep '^less \d' &>/dev/null; then
 			_SCRIPT_PAGER_NAME="less"

lib/str.sh

@@ -8,10 +8,10 @@
 
 # Converts a string to lower case.
 tolower() {
-	tr "[[:upper:]]" "[[:lower:]]" <<<"$1"
+	tr "[:upper:]" "[:lower:]" <<<"$1"
 }
 
 # Converts a string to upper case.
 toupper() {
-	tr "[[:lower:]]" "[[:upper:]]" <<<"$1"
+	tr "[:lower:]" "[:upper:]" <<<"$1"
 }

src/batgrep.sh

@@ -169,7 +169,7 @@ if "$OPT_SEARCH_PATTERN"; then
 		fi
 	elif is_pager_disabled; then
 		print_error "$(
-			echo "The -p/--search-pattern option requires a pager, but" \
+			"The -p/--search-pattern option requires a pager, but" \
 				"the pager was explicitly disabled by \$BAT_PAGER or the" \
 				"--paging option."
 		)"

src/batman.sh

@@ -21,16 +21,18 @@ BAT_ARGS=()
 
 while shiftopt; do MAN_ARGS+=("$OPT"); done
 if "$OPT_COLOR"; then
-	BAT_ARGS="--color=always --decorations=always"
+	BAT_ARGS=("--color=always --decorations=always")
 else
-	BAT_ARGS="--color=never --decorations=never"
+	BAT_ARGS=("--color=never --decorations=never")
 fi
 # -----------------------------------------------------------------------------
-export MANPAGER='sh -c "col -bx | '"$(printf "%q" "$BAT")"' --language=man --style=grid '"${BAT_ARGS[@]}"'"'
+export MANPAGER
+MANPAGER='sh -c "col -bx | '"$(printf "%q" "$BAT")"' --language=man --style=grid '"${BAT_ARGS[*]}"'"'
 export MANROFFOPT='-c'
 
 if [[ -n "${SCRIPT_PAGER_CMD}" ]]; then
-	export BAT_PAGER="$(printf "%q " "${SCRIPT_PAGER_CMD[@]}" "${SCRIPT_PAGER_ARGS[@]}")"
+	export BAT_PAGER
+	BAT_PAGER="$(printf "%q " "${SCRIPT_PAGER_CMD[@]}" "${SCRIPT_PAGER_ARGS[@]}")"
 else
 	unset BAT_PAGER
 fi

src/batwatch.sh

@@ -184,7 +184,7 @@ while shiftopt; do
 	esac
 done
 
-if [[ -z "$FILES" ]]; then
+if [[ ${#FILES[@]} -eq 0 ]]; then
 	print_error "no files provided"
 	exit 1
 fi
@@ -213,7 +213,7 @@ fi
 # Determine the watcher.
 if [[ -z "$OPT_WATCHER" ]]; then
 	OPT_WATCHER="$(determine_watcher)"
-	if [[ $? -ne 0 ]]; then
+	if ! "$OPT_WATCHER"; then
 		print_error "Your system does not have any supported watchers."
 		printc "Please read the documentation at %{BLUE}%s%{CLEAR} for more details.\n" "$DOCS_URL/batwatch.md" 1>&2
 		exit 2

src/prettybat.sh

@@ -152,7 +152,8 @@ process_file() {
 		fext="$(map_language_to_extension "$lang")"
 	fi
 
-	local formatter="$(map_extension_to_formatter "$fext")"
+	local formatter
+	formatter="$(map_extension_to_formatter "$fext")"
 	echo "FORMATTER >>> $formatter"
 	if [[ "$formatter" = "none" ]]; then
 		if [[ -z "$OPT_LANGUAGE" ]]; then
@@ -170,14 +171,14 @@ process_file() {
 	if [[ "$file" = "-" ]]; then
 		data_raw="$(cat -)"
 		data_formatted="$("formatter_${formatter}_process" "$file" 2>/dev/null <<<"$data_raw")"
-		if [[ $? -ne 0 ]]; then
+		if "$data_formatted"; then
 			print_warning "'STDIN': Unable to format with '%s'" "$formatter"
 			print_file --language="$lang" - <<<"$data_raw"
 			return 1
 		fi
 	else
 		data_formatted="$("formatter_${formatter}_process" "$file" <"$file")"
-		if [[ $? -ne 0 ]]; then
+		if ! "$data_formatted"; then
 			print_warning "'%s': Unable to format with '%s'" "$file" "$formatter"
 			print_file --language="$lang" "$file"
 			return 1
@@ -224,7 +225,7 @@ while shiftopt; do
 done
 
 if [[ "${#FILES[@]}" -eq 0 ]]; then
-	FILES="-"
+	FILES=("-")
 fi
 
 # Handle input files.
@@ -236,4 +237,4 @@ for file in "${FILES[@]}"; do
 done
 
 # Exit.
-exit $EXIT
+exit "$EXIT"

test.sh

@@ -9,7 +9,7 @@ HERE="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 LIB="${HERE}/lib"
 source "${LIB}/opt.sh"
 # -----------------------------------------------------------------------------
-cd "$HERE"
+cd "$HERE" || exit
 
 # -----------------------------------------------------------------------------
 export TEST_ENV_LIB="${HERE}/lib"