From 2dc29233bf0d6c7a3532f58c98683c9923cd7eae Mon Sep 17 00:00:00 2001
From: Yuuki Toriyama <github@toriyama.dev>
Date: Tue, 3 Sep 2024 22:59:04 +0900
Subject: [PATCH 1/2] =?UTF-8?q?add:=20#400:=20=E6=96=87=E5=AD=97=E3=81=8C?=
 =?UTF-8?q?=E7=95=B0=E5=AD=97=E4=BD=93=E3=82=BB=E3=83=AC=E3=82=AF=E3=82=BF?=
 =?UTF-8?q?=E3=81=8B=E3=81=A9=E3=81=86=E3=81=8B=E3=82=92=E5=88=A4=E5=AE=9A?=
 =?UTF-8?q?=E3=81=99=E3=82=8B=E3=83=A1=E3=82=BD=E3=83=83=E3=83=89=E3=82=92?=
 =?UTF-8?q?=E5=AE=9A=E7=BE=A9?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

https://en.wikipedia.org/wiki/Variant_form_(Unicode)
---
 core/src/util.rs           |  1 +
 core/src/util/extension.rs | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 core/src/util/extension.rs

diff --git a/core/src/util.rs b/core/src/util.rs
index 09d7245b..62ca0efa 100644
--- a/core/src/util.rs
+++ b/core/src/util.rs
@@ -1,3 +1,4 @@
 pub mod converter;
+pub(crate) mod extension;
 pub mod sequence_matcher;
 mod trimmer;
diff --git a/core/src/util/extension.rs b/core/src/util/extension.rs
new file mode 100644
index 00000000..9a04fada
--- /dev/null
+++ b/core/src/util/extension.rs
@@ -0,0 +1,33 @@
+pub(crate) trait CharExt {
+    fn is_variation_selector(&self) -> bool;
+}
+
+impl CharExt for char {
+    /// 異字体セレクタかどうかを判別します
+    fn is_variation_selector(&self) -> bool {
+        matches!(self, '\u{FE00}'..='\u{FE0F}' | '\u{E0100}'..='\u{E01EF}')
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::util::extension::CharExt;
+
+    #[test]
+    fn is_variation_selector() {
+        assert_eq!('あ'.is_variation_selector(), false);
+        assert_eq!('亜'.is_variation_selector(), false);
+
+        assert_eq!('\u{FDFF}'.is_variation_selector(), false);
+        assert_eq!('\u{FE00}'.is_variation_selector(), true);
+
+        assert_eq!('\u{FE0F}'.is_variation_selector(), true);
+        assert_eq!('\u{FE10}'.is_variation_selector(), false);
+
+        assert_eq!('\u{E00FF}'.is_variation_selector(), false);
+        assert_eq!('\u{E0100}'.is_variation_selector(), true);
+
+        assert_eq!('\u{E01EF}'.is_variation_selector(), true);
+        assert_eq!('\u{E01F0}'.is_variation_selector(), false);
+    }
+}

From e04e8a24025db83de17966ede51d8a330de672d1 Mon Sep 17 00:00:00 2001
From: Yuuki Toriyama <github@toriyama.dev>
Date: Tue, 3 Sep 2024 23:19:40 +0900
Subject: [PATCH 2/2] =?UTF-8?q?add:=20#400:=20=E6=96=87=E5=AD=97=E5=88=97?=
 =?UTF-8?q?=E3=81=8B=E3=82=89=E7=95=B0=E5=AD=97=E4=BD=93=E3=82=BB=E3=83=AC?=
 =?UTF-8?q?=E3=82=AF=E3=82=BF=E3=82=92=E5=8F=96=E3=82=8A=E9=99=A4=E3=81=8F?=
 =?UTF-8?q?=E3=83=A1=E3=82=BD=E3=83=83=E3=83=89=E3=82=92=E5=AE=9A=E7=BE=A9?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 core/src/util/extension.rs | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/core/src/util/extension.rs b/core/src/util/extension.rs
index 9a04fada..f7a81cf3 100644
--- a/core/src/util/extension.rs
+++ b/core/src/util/extension.rs
@@ -9,9 +9,22 @@ impl CharExt for char {
     }
 }
 
+pub(crate) trait StrExt {
+    fn strip_variation_selectors(&self) -> String;
+}
+
+impl StrExt for str {
+    /// 文字列から異字体セレクタを取り除きます
+    fn strip_variation_selectors(&self) -> String {
+        self.chars()
+            .filter(|c| !c.is_variation_selector())
+            .collect()
+    }
+}
+
 #[cfg(test)]
 mod tests {
-    use crate::util::extension::CharExt;
+    use crate::util::extension::{CharExt, StrExt};
 
     #[test]
     fn is_variation_selector() {
@@ -30,4 +43,20 @@ mod tests {
         assert_eq!('\u{E01EF}'.is_variation_selector(), true);
         assert_eq!('\u{E01F0}'.is_variation_selector(), false);
     }
+
+    #[test]
+    fn strip_variation_selectors_逢坂() {
+        let normal = "\u{9022}\u{5742}"; // 逢坂
+        let variant = "\u{9022}\u{E0101}\u{5742}"; // 逢󠄁坂
+        assert_ne!(normal, variant);
+        assert_eq!(normal, variant.strip_variation_selectors());
+    }
+
+    #[test]
+    fn strip_variation_selectors_茨城() {
+        let normal = "\u{8328}\u{57CE}";
+        let variant = "\u{8328}\u{E0100}\u{57CE}";
+        assert_ne!(normal, variant);
+        assert_eq!(normal, variant.strip_variation_selectors());
+    }
 }