Merge pull request #52 from rust-analyzer/constify

Author: Veykril

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "text-size"
-version = "1.1.0"
+version = "1.1.1"
 edition = "2018"
 
 authors = [

src/range.rs

@@ -44,8 +44,8 @@ impl TextRange {
     /// assert_eq!(range.len(), end - start);
     /// ```
     #[inline]
-    pub fn new(start: TextSize, end: TextSize) -> TextRange {
-        assert!(start <= end);
+    pub const fn new(start: TextSize, end: TextSize) -> TextRange {
+        assert!(start.raw <= end.raw);
         TextRange { start, end }
     }
 
@@ -65,8 +65,8 @@ impl TextRange {
     /// assert_eq!(&text[range], "23456")
     /// ```
     #[inline]
-    pub fn at(offset: TextSize, len: TextSize) -> TextRange {
-        TextRange::new(offset, offset + len)
+    pub const fn at(offset: TextSize, len: TextSize) -> TextRange {
+        TextRange::new(offset, TextSize::new(offset.raw + len.raw))
     }
 
     /// Create a zero-length range at the specified offset (`offset..offset`).
@@ -82,7 +82,7 @@ impl TextRange {
     /// assert_eq!(range, TextRange::new(point, point));
     /// ```
     #[inline]
-    pub fn empty(offset: TextSize) -> TextRange {
+    pub const fn empty(offset: TextSize) -> TextRange {
         TextRange {
             start: offset,
             end: offset,
@@ -104,9 +104,9 @@ impl TextRange {
     /// assert_eq!(range, TextRange::at(0.into(), point));
     /// ```
     #[inline]
-    pub fn up_to(end: TextSize) -> TextRange {
+    pub const fn up_to(end: TextSize) -> TextRange {
         TextRange {
-            start: 0.into(),
+            start: TextSize::new(0),
             end,
         }
     }

src/size.rs

@@ -33,6 +33,12 @@ impl fmt::Debug for TextSize {
 }
 
 impl TextSize {
+    /// Creates a new instance of `TextSize` from a raw `u32`.
+    #[inline]
+    pub const fn new(raw: u32) -> TextSize {
+        TextSize { raw }
+    }
+
     /// The text size of some primitive text-like object.
     ///
     /// Accepts `char`, `&str`, and `&String`.
@@ -58,14 +64,20 @@ impl TextSize {
 impl TextSize {
     /// Checked addition. Returns `None` if overflow occurred.
     #[inline]
-    pub fn checked_add(self, rhs: TextSize) -> Option<TextSize> {
-        self.raw.checked_add(rhs.raw).map(|raw| TextSize { raw })
+    pub const fn checked_add(self, rhs: TextSize) -> Option<TextSize> {
+        match self.raw.checked_add(rhs.raw) {
+            Some(raw) => Some(TextSize { raw }),
+            None => None,
+        }
     }
 
     /// Checked subtraction. Returns `None` if overflow occurred.
     #[inline]
-    pub fn checked_sub(self, rhs: TextSize) -> Option<TextSize> {
-        self.raw.checked_sub(rhs.raw).map(|raw| TextSize { raw })
+    pub const fn checked_sub(self, rhs: TextSize) -> Option<TextSize> {
+        match self.raw.checked_sub(rhs.raw) {
+            Some(raw) => Some(TextSize { raw }),
+            None => None,
+        }
     }
 }
 

tests/indexing.rs

@@ -3,6 +3,6 @@ use text_size::*;
 #[test]
 fn main() {
     let range = TextRange::default();
-    &""[range];
-    &String::new()[range];
+    _ = &""[range];
+    _ = &String::new()[range];
 }