dist/tools: check for colons in commit-msg script

Author: crasbe

dist/tools/commit-msg/check.sh

@@ -58,10 +58,12 @@ fi
 ERROR="$(git log \
     --no-merges --pretty=format:'%s' "$(git merge-base "${BRANCH}" HEAD)"..HEAD | \
     while read -r msg; do
-        msg_length="$(echo "${msg}" | awk '{print length($0)}')"
+        ERROR=0
+        MSG=""
 
+        # Check if the message is too long.
+        msg_length="$(echo "${msg}" | awk '{print length($0)}')"
         if [ "${msg_length}" -gt "${MSG_MAX_LENGTH}" ]; then
-            ERROR=0
             if [ "${msg_length}" -gt "${MSG_STRETCH_LENGTH}" ]; then
                 MSG="Commit message is longer than ${MSG_STRETCH_LENGTH} characters:"
                 ERROR=1
@@ -70,6 +72,23 @@ ERROR="$(git log \
                 MSG="Commit message is longer than ${MSG_MAX_LENGTH}"
                 MSG="${MSG} (but < ${MSG_STRETCH_LENGTH}) characters:"
             fi
+        fi
+
+        # Check if the message has a colon and if the first colon is followed
+        # by a space.
+        if echo "$msg" | grep -q ":"; then
+            if ! echo "$msg" | grep -Eq '^[^:]*: '; then
+                MSG="The colon after the area designation is not followed by"
+                MSG="${MSG} a space."
+            fi
+        else
+            MSG="The commit message is missing a colon after the area"
+            MSG="${MSG} designation."
+            ERROR=1
+            echo "error"
+        fi
+
+        if [ -n "${MSG}" ]; then
             if github_annotate_is_on; then
                 if [ ${ERROR} -eq 1 ]; then
                     github_annotate_error_no_file "${MSG} \"${msg}\""