refactor: improve condition

Refactor contact entry URL generation logic to skip entries without usernames or emails.

Signed-off-by: Cotes Chung <[email protected]>

Author: cotes2020

_includes/sidebar.html

@@ -52,17 +52,21 @@
     {% endunless %}
 
     {% for entry in site.data.contact %}
+      {%- assign url = null -%}
+
       {% case entry.type %}
         {% when 'github', 'twitter' %}
-          {% if site[entry.type].username %}
-            {%- capture url -%}
-              https://{{ entry.type }}.com/{{ site[entry.type].username }}
-            {%- endcapture -%}
-          {% else %}
-            {% assign url = nil %}
-          {% endif %}
+          {%- unless site[entry.type].username -%}
+            {%- continue -%}
+          {%- endunless -%}
+          {%- capture url -%}
+            https://{{ entry.type }}.com/{{ site[entry.type].username }}
+          {%- endcapture -%}
         {% when 'email' %}
-          {% assign email = site.social.email | split: '@' %}
+          {%- unless site.social.email -%}
+            {%- continue -%}
+          {%- endunless -%}
+          {%- assign email = site.social.email | split: '@' -%}
           {%- capture url -%}
             javascript:location.href = 'mailto:' + ['{{ email[0] }}','{{ email[1] }}'].join('@')
           {%- endcapture -%}