Use welcoming language (#15)

Motivation:
The Swift community wants to be open and welcoming.

Modifications:

- Removes language that can be seen as unwelcoming
- Add CI step to detect offensive language

Result:
A more welcoming project.

Author: yim-lee

docker/docker-compose.yaml

@@ -22,9 +22,9 @@ services:
       - CAP_NET_RAW
       - CAP_NET_BIND_SERVICE
 
-  sanity:
+  soundness:
     <<: *common
-    command: /bin/bash -xcl "./scripts/sanity.sh"
+    command: /bin/bash -xcl "./scripts/soundness.sh"
 
   test:
     <<: *common

scripts/sanity.sh renamed to scripts/soundness.sh

@@ -22,6 +22,22 @@ function replace_acceptable_years() {
     sed -e 's/2020-2021/YEARS/' -e 's/2020/YEARS/' -e 's/2021/YEARS/'
 }
 
+printf "=> Checking for unacceptable language... "
+# This greps for unacceptable terminology. The square bracket[s] are so that
+# "git grep" doesn't find the lines that greps :).
+unacceptable_terms=(
+    -e blacklis[t]
+    -e whitelis[t]
+    -e slav[e]
+    -e sanit[y]
+)
+if git grep --color=never -i "${unacceptable_terms[@]}" > /dev/null; then
+    printf "\033[0;31mUnacceptable language found.\033[0m\n"
+    git grep -i "${unacceptable_terms[@]}"
+    exit 1
+fi
+printf "\033[0;32mokay.\033[0m\n"
+
 printf "=> Checking format... "
 FIRST_OUT="$(git status --porcelain)"
 swiftformat . > /dev/null 2>&1