Merge search logic and separate variables

This commit merge the search logic from 'get_match_position' into
'get_all_match_positions'. Also, directly modifying 'FULL_COMMIT_MSG' is
not acceptable. Therefore, separate 'FULL_COMMIT_MSG_WITH_SPACE' and
'MSG_FOR_SPELLCHECK_LINE_FINDING' variables are created for subsequent
line number look-ups.

Change-Id: I5f98b3989acbf4c22c1eb7bd300bf66fd6e62826

scripts/commit-msg.hook

@@ -125,36 +125,42 @@ read_commit_message() {
 }
 
 #
-# Get the position (line and column) of the first occurrence of a target string.
+# Get positions (line,column) for each target word from aspell output.
 #
-
-get_match_position() {
-  local text="$1" target="$2"
-  local start_line="${3:-1}" start_col="${4:-1}"
-  awk -v t="$target" -v sl="$start_line" -v sc="$start_col" '{
-    if (NR < sl) next
-    pos = index(NR == sl ? substr($0, sc) : $0, t)
-    if (pos) {
-      print NR, (NR == sl ? pos + sc - 1 : pos)
-      exit
-    }
-  }' <<< "$text"
-}
-
 #
-# Get positions (line,column) for each target word from aspell output.
+# Get positions (line, column) for each target word in a multiline string.
+# Output format: "target: line"
 #
-
 get_all_match_positions() {
-  local text="$1" targets="$2"
-  local start_line=1 start_col=1
+  local text="$1"
+  local targets="$2"
+  local start_line=1
+  local start_col=1
+
   while IFS= read -r target; do
-    result=$(get_match_position "$text" "$target" "$start_line" "$start_col")
+    # search for the target string
+    local result
+    result=$(
+      awk -v t="$target" -v sl="$start_line" -v sc="$start_col" '{
+        if (NR < sl) next
+        pos = index(NR == sl ? substr($0, sc) : $0, t)
+        if (pos) {
+          print NR, (NR == sl ? pos + sc - 1 : pos)
+          exit
+        }
+      }' <<< "$text"
+    )
+
+    # skip if the target is not found
     [ -z "$result" ] && continue
+
+    # output and update states
+    local line col
     read -r line col <<< "$result"
     echo "$target: $line"
     start_line="$line"
     start_col=$((col + 1))
+
   done <<< "$targets"
 }
 
@@ -382,8 +388,9 @@ done
   # 12. Avoid abusive language in commit message content
   # ------------------------------------------------------------------------------
 
-  FULL_COMMIT_MSG=$(sed '/^#/d;/^[[:space:]]*Change-Id:/d' "$COMMIT_MSG_FILE" | \
-                    sed -E "s@${URL_REGEX#^}@@g")
+  FULL_COMMIT_MSG_WITH_SPACE=$(sed '/^#/d;/^[[:space:]]*Change-Id:/d' "$COMMIT_MSG_FILE" | \
+                               sed -E "s@${URL_REGEX#^}@@g")
+  FULL_COMMIT_MSG=$(echo "$FULL_COMMIT_MSG_WITH_SPACE" | sed '/^[[:space:]]*$/d')
 
   # Extended list of abusive words (case-insensitive).
   # Adjust the list as needed.
@@ -402,14 +409,16 @@ done
     add_warning 1 "Commit message appears to be written in Chinese: $MISSPELLED_WORDS"
   fi
 
-  MSG_FOR_SPELLCHECK=$(echo "$FULL_COMMIT_MSG" | sed -E \
+  MSG_FOR_SPELLCHECK_LINE_FINDING=$(echo "$FULL_COMMIT_MSG_WITH_SPACE" | sed -E \
     -e "s/(['\"][^'\"]*['\"])//g" \
     -e "s/\bcommit[[:space:]]+[0-9a-fA-F]{7,40}\b/commit/g")
+  MSG_FOR_SPELLCHECK=$(echo "$MSG_FOR_SPELLCHECK_LINE_FINDING" | sed '/^[[:space:]]*$/d')
+
 
   # Use aspell to list misspelled words according to American English, ignoring quoted text.
   MISSPELLED_WORDS=$(echo "$MSG_FOR_SPELLCHECK" | $ASPELL --lang=en --list --home-dir=scripts --personal=aspell-pws)
   if [ -n "$MISSPELLED_WORDS" ]; then
-    results=$(get_all_match_positions "$MSG_FOR_SPELLCHECK" "$MISSPELLED_WORDS")
+    results=$(get_all_match_positions "$MSG_FOR_SPELLCHECK_LINE_FINDING" "$MISSPELLED_WORDS")
 
     while read -r result; do
       add_warning "${result#*:}" "Avoid using non-American English words: ${result%%:*}"