casks: Find correct FamilyName if font has multiple families

[why]
Some fonts have different and not consistent Family names set,
especially (only) if the `--makegroups` option has not been used for
patching.

Example:
$ fc-query --format='%{family}\n' patched-fonts/Hasklig/Black/complete/Hasklug\ Black\ Nerd\ Font\ Complete.otf
Hasklug Nerd Font,Hasklig Black

See also previous commit's message, bottom.

[how]
We want to use only one of the Family names (fc-query reports all as
csv, unless we specify an index), so query one by one.
Check that it is 'our' name (that contains "Nerd") and not a leftover
from uncomplete patching.

[note]
Also whitespace change: One tab to spaces.

Signed-off-by: Fini Jastrow <ulf.fini.jastrow@desy.de>

bin/scripts/generate-casks.sh

@@ -38,6 +38,25 @@ function write_header {
     } >> "$outputfile"
 }
 
+# Query all Family names of a font individually and return the first
+# we found that has "Nerd" in it. We need this because some fonts have
+# broken Family names.
+function find_nerdish_family {
+    local fontfile=$1
+    local idx=0
+    while :; do
+        local fn=$(fc-query --format="%{family[${idx}]}" "${fontfile}")
+        if [ -z "$fn" ]; then
+            return
+        fi
+        if [[ "${fn}" == *Nerd* ]]; then
+            echo "${fn}"
+            return
+        fi
+        idx=$((${idx} + 1))
+    done
+}
+
 function write_body {
     local unpatchedname=$1
     local outputfile=$2
@@ -54,13 +73,20 @@ function write_body {
             fi
         done
         # Find familyname of non Mono variant (well, rather shortest because we can contain multiple families)
-        familyname=$(fc-query --format='%{family}' "${fonts[0]}")
+        familyname=$(find_nerdish_family "${fonts[0]}")
         for i in "${!fonts[@]}"; do
-            fn=$(fc-query --format='%{family}' "${fonts[$i]}")
+            fn=$(find_nerdish_family "${fonts[$i]}")
+            if [ -z "${fn}" ]; then
+                break
+            fi
             if [ "${#fn}" -lt "${#familyname}" ]; then
                 familyname=${fn}
             fi
         done
+        if [ -z "${familyname}" ]; then
+            echo >&2 "${LINE_PREFIX} Can not determine family name"
+            exit 2
+        fi
         # Process font files
         for i in "${!fonts[@]}"; do
             individualfont=$(basename "${fonts[$i]}")