Find emoji

CHANGELOG.md

@@ -15,6 +15,7 @@ Procedure when bumping the version number:
 
 ### Added
 - All emoji known to the vanilla client
+- Finding emoji in text
 - `State` conversion utility methods
 - `Time::new` constructor
 

src/emoji.rs

@@ -1,6 +1,7 @@
 //! All emoji the vanilla euphoria.io client knows.
 
 use std::collections::HashMap;
+use std::ops::RangeInclusive;
 
 const EMOJI_RAW: &str = include_str!("emoji.txt");
 
@@ -30,6 +31,34 @@ impl Emoji {
             .collect();
         Self(map)
     }
+
+    pub fn get(&self, name: &str) -> Option<Option<&str>> {
+        match self.0.get(name) {
+            Some(Some(replace)) => Some(Some(replace)),
+            Some(None) => Some(None),
+            None => None,
+        }
+    }
+
+    pub fn find(&self, text: &str) -> Vec<(RangeInclusive<usize>, Option<&str>)> {
+        let mut result = vec![];
+
+        let mut prev_colon_idx = None;
+        for (colon_idx, _) in text.match_indices(':') {
+            if let Some(prev_idx) = prev_colon_idx {
+                let name = &text[prev_idx + 1..colon_idx];
+                if let Some(replace) = self.get(name) {
+                    let range = prev_idx..=colon_idx;
+                    result.push((range, replace));
+                    prev_colon_idx = None;
+                    continue;
+                }
+            }
+            prev_colon_idx = Some(colon_idx);
+        }
+
+        result
+    }
 }
 
 #[cfg(test)]
@@ -40,4 +69,22 @@ mod test {
     fn load_without_panic() {
         Emoji::load();
     }
+
+    #[test]
+    fn find() {
+        let emoji = Emoji::load();
+
+        // :bad: does not exist, while :x: and :o: do.
+
+        assert_eq!(emoji.find(":bad:x:o:"), vec![(4..=6, Some("❌"))]);
+        assert_eq!(
+            emoji.find(":x:bad:o:"),
+            vec![(0..=2, Some("❌")), (6..=8, Some("⭕"))]
+        );
+        assert_eq!(emoji.find("ab:bad:x:o:cd"), vec![(6..=8, Some("❌"))]);
+        assert_eq!(
+            emoji.find("ab:x:bad:o:cd"),
+            vec![(2..=4, Some("❌")), (8..=10, Some("⭕"))]
+        );
+    }
 }