That didn't work. Is this better solution?

Author: dotysan

.github/workflows/build.yml

@@ -26,7 +26,6 @@ jobs:
 
       - name: Deduce tags
         run: |
-          git fetch --tags  # does this fix shallow clone?
           mkdir source
           echo "latest" > source/tags
           if tag=$(git describe --exact-match --tags)

setgitversion

@@ -7,5 +7,10 @@ file="src/ShellCheck/Data.hs"
 test -e "$file"
 tmp=$(mktemp)
 version=$(git describe)
+if [ -z "$version" ]
+then
+    short_commit=$(git rev-parse --short HEAD)
+    version="0.0.0-g$short_commit"
+fi
 sed -e "s/=.*VERSIONSTRING.*/= \"$version\" -- VERSIONSTRING, DO NOT SUBMIT/" "$file" > "$tmp"
 mv "$tmp" "$file"