diff --git a/Library/Homebrew/utils/shfmt.sh b/Library/Homebrew/utils/shfmt.sh
index a0f66a2f47..3359a6adf4 100755
--- a/Library/Homebrew/utils/shfmt.sh
+++ b/Library/Homebrew/utils/shfmt.sh
@@ -227,21 +227,21 @@ no_forbidden_styles() {
 align_multiline_if_condition() {
   local line
   local lastline=''
-  local base_indent=''  # indents before `if`
-  local extra_indent='' # 2 extra spaces for `elif`
-  local multiline_if_begin_regex='^( *)(el)?if '
-  local multiline_then_end_regex='^(.*)\; (then( *#.*)?)$'
-  local within_test_regex='^( *)(((! )?-[fdLrwxeszn] )|([^\[]+ == ))'
+  local base_indent=''       # indents before `if`
+  local elif_extra_indent='' # 2 extra spaces for `elif`
+  local multiline_if_then_begin_regex='^( *)(el)?if '
+  local multiline_if_then_end_regex='^(.*)\; (then( *#.*)?)$'
+  local within_test_regex='^( *)(((! )?-[fdLrwxeszn] )|([^\[]+ (==|!=|=~) ))'
 
   trim() {
     [[ "$1" =~ [^[:space:]](.*[^[:space:]])? ]]
     printf "%s" "${BASH_REMATCH[0]}"
   }
 
-  if [[ "$1" =~ ${multiline_if_begin_regex} ]]
+  if [[ "$1" =~ ${multiline_if_then_begin_regex} ]]
   then
     base_indent="${BASH_REMATCH[1]}"
-    [[ -n "${BASH_REMATCH[2]}" ]] && extra_indent='  '
+    [[ -n "${BASH_REMATCH[2]}" ]] && elif_extra_indent='  ' # 2 extra spaces for `elif`
     echo "$1"
     shift
   fi
@@ -250,16 +250,21 @@ align_multiline_if_condition() {
   do
     line="$1"
     shift
-    if [[ "${line}" =~ ${multiline_then_end_regex} ]]
+    if [[ "${line}" =~ ${multiline_if_then_end_regex} ]]
     then
       line="${BASH_REMATCH[1]}"
       lastline="${base_indent}${BASH_REMATCH[2]}"
     fi
     if [[ "${line}" =~ ${within_test_regex} ]]
     then
-      echo "${base_indent}${extra_indent}      $(trim "${line}")"
+      # Add 3 extra spaces (6 spaces in total) to multiline test conditions
+      # before:                   after:
+      #   if [[ -n ... ||           if [[ -n ... ||
+      #     -n ... ]]                     -n ... ]]
+      #   then                      then
+      echo "${base_indent}${elif_extra_indent}      $(trim "${line}")"
     else
-      echo "${base_indent}${extra_indent}   $(trim "${line}")"
+      echo "${base_indent}${elif_extra_indent}   $(trim "${line}")"
     fi
   done
 
@@ -287,24 +292,28 @@ wrap_then_do() {
   local -a processed=()
   local -a buffer=()
   local line
-  local singleline_then_regex='^( *)(el)?if (.+)\; (then( *#.*)?)$'
-  local singleline_do_regex='^( *)(for|while) (.+)\; (do( *#.*)?)$'
-  local multiline_if_begin_regex='^( *)(el)?if '
-  local multiline_then_end_regex='^(.*)\; (then( *#.*)?)$'
+  local singleline_if_then_fi_regex='^( *)if (.+)\; then (.+)\; fi( *#.*)?$'
+  local singleline_if_then_regex='^( *)(el)?if (.+)\; (then( *#.*)?)$'
+  local singleline_for_do_regex='^( *)(for|while) (.+)\; (do( *#.*)?)$'
+  local multiline_if_then_begin_regex='^( *)(el)?if '
+  local multiline_if_then_end_regex='^(.*)\; (then( *#.*)?)$'
 
   while IFS='' read -r line
   do
     if [[ "${#buffer[@]}" == 0 ]]
     then
-      if [[ "${line}" =~ ${singleline_then_regex} ]]
+      if [[ "${line}" =~ ${singleline_if_then_fi_regex} ]]
+      then
+        processed+=("${line}")
+      elif [[ "${line}" =~ ${singleline_if_then_regex} ]]
       then
         processed+=("${BASH_REMATCH[1]}${BASH_REMATCH[2]}if ${BASH_REMATCH[3]}")
         processed+=("${BASH_REMATCH[1]}${BASH_REMATCH[4]}")
-      elif [[ "${line}" =~ ${singleline_do_regex} ]]
+      elif [[ "${line}" =~ ${singleline_for_do_regex} ]]
       then
         processed+=("${BASH_REMATCH[1]}${BASH_REMATCH[2]} ${BASH_REMATCH[3]}")
         processed+=("${BASH_REMATCH[1]}${BASH_REMATCH[4]}")
-      elif [[ "${line}" =~ ${multiline_if_begin_regex} ]]
+      elif [[ "${line}" =~ ${multiline_if_then_begin_regex} ]]
       then
         buffer=("${line}")
       else
@@ -312,7 +321,7 @@ wrap_then_do() {
       fi
     else
       buffer+=("${line}")
-      if [[ "${line}" =~ ${multiline_then_end_regex} ]]
+      if [[ "${line}" =~ ${multiline_if_then_end_regex} ]]
       then
         while IFS='' read -r line
         do
@@ -351,7 +360,7 @@ format() {
       return 1
     fi
 
-    tempfile="$(dirname "${file}")/.${file##*/}.temp"
+    tempfile="$(dirname "${file}")/.${file##*/}.formatted~"
     cp -af "${file}" "${tempfile}"
   fi
   trap 'rm -f "${tempfile}" 2>/dev/null' RETURN
@@ -396,6 +405,8 @@ format() {
     then
       cp -af "${tempfile}" "${file}"
     else
+      # Show a linebreak between outputs
+      [[ "${RETCODE}" != 0 ]] && onoe
       # Show differences
       "${DIFF}" "${DIFF_ARGS[@]}" "${file}" "${tempfile}" 1>&2
     fi
@@ -434,7 +445,6 @@ do
       4) onoe "${0##*/}: Fixable bad styles detected in file \"${file}\", run \`brew style --fix\` to apply. Formatter exited with code 4." ;;
       *) onoe "${0##*/}: Failed to format file \"${file}\". Formatter exited with code ${retcode}." ;;
     esac
-    onoe
     RETCODE=1
   fi
 done