Don't attempt to send "empty" embeds

src/postman/sender.rs

@@ -195,21 +195,100 @@ impl Embed {
     }
 
     pub fn has_content(&self) -> bool {
-        if self.title.is_empty()
+        // Discord reports "description required" for empty embeds, but descriptions are optional.
-            && self.description.is_empty()
+        // An author icon alone does not count as content; a footer icon does.
-            && self.image_url.is_none()
+        !self.title.trim().is_empty()
-            && self.thumbnail_url.is_none()
+            || !self.description.trim().is_empty()
-            && self.footer.is_empty()
+            || self.image_url.as_ref().is_some_and(|url| !url.trim().is_empty())
-            && self.footer_url.is_none()
+            || self.thumbnail_url.as_ref().is_some_and(|url| !url.trim().is_empty())
-            && self.author.is_empty()
+            || !self.footer.trim().is_empty()
-            && self.author_url.is_none()
+            || self.footer_url.as_ref().is_some_and(|url| !url.trim().is_empty())
-            && self.fields.0.is_empty()
+            || !self.author.trim().is_empty()
-        {
+            || !self.fields.0.is_empty()
-            false
+    }
-        } else {
+}
-            true
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn embed(description: &str) -> Embed {
+        Embed {
+            title: String::new(),
+            description: description.to_string(),
+            image_url: None,
+            thumbnail_url: None,
+            footer: String::new(),
+            footer_url: None,
+            author: String::new(),
+            author_url: None,
+            color: 0,
+            fields: Json(vec![]),
         }
     }
+
+    #[test]
+    fn embed_without_description_can_have_content() {
+        let url = Some("https://example.com/image.png".to_string());
+        let embeds = [
+            Embed { title: "Reminder".to_string(), ..embed("") },
+            Embed { image_url: url.clone(), ..embed("") },
+            Embed { thumbnail_url: url.clone(), ..embed("") },
+            Embed { footer: "Footer".to_string(), ..embed("") },
+            Embed { footer_url: url, ..embed("") },
+            Embed { author: "Author".to_string(), ..embed("") },
+            Embed {
+                fields: Json(vec![EmbedField {
+                    title: String::new(),
+                    value: String::new(),
+                    inline: false,
+                }]),
+                ..embed("")
+            },
+        ];
+
+        for embed in embeds {
+            assert!(embed.has_content());
+        }
+    }
+
+    #[test]
+    fn empty_embed_after_substitution_has_no_content() {
+        let mut embed = embed("<<timenow:Invalid/Timezone:%H>>");
+        embed.author_url = Some("https://example.com/image.png".to_string());
+        embed.description = substitute(&embed.description);
+
+        assert!(embed.description.is_empty());
+        assert!(!embed.has_content());
+    }
+
+    #[test]
+    fn embed_with_only_description_has_content() {
+        assert!(embed("Remember to do the thing").has_content());
+    }
+
+    #[test]
+    fn empty_or_whitespace_embed_has_no_content() {
+        assert!(!embed("").has_content());
+        let embed = Embed {
+            title: " \n\t ".to_string(),
+            image_url: Some(String::new()),
+            thumbnail_url: Some(" ".to_string()),
+            footer: " \n\t ".to_string(),
+            footer_url: Some(String::new()),
+            author: " \n\t ".to_string(),
+            color: 12345,
+            ..embed(" \n\t ")
+        };
+        assert!(!embed.has_content());
+    }
+
+    #[test]
+    fn author_icon_alone_has_no_content() {
+        let embed =
+            Embed { author_url: Some("https://example.com/image.png".to_string()), ..embed("") };
+        assert!(!embed.has_content());
+    }
 }
 
 impl Into<CreateEmbed> for Embed {