Fix docs
diff --git a/src/range.rs b/src/range.rs
index 3b946ab..fcf286d 100644
--- a/src/range.rs
+++ b/src/range.rs
@@ -98,8 +98,8 @@
     /// let range = TextRange::up_to(point);
     ///
     /// assert_eq!(range.len(), point);
-    /// assert_eq!(range, TextRange::new(TextSize::zero(), point));
-    /// assert_eq!(range, TextRange::at(TextSize::zero(), point));
+    /// assert_eq!(range, TextRange::new(0.into(), point));
+    /// assert_eq!(range, TextRange::at(0.into(), point));
     /// ```
     #[inline]
     pub fn up_to(end: TextSize) -> TextRange {
@@ -254,7 +254,7 @@
     /// ```rust
     /// # use text_size::*;
     /// assert_eq!(
-    ///     TextRange::empty(TextSize::zero()).cover_offset(20.into()),
+    ///     TextRange::empty(0.into()).cover_offset(20.into()),
     ///     TextRange::new(0.into(), 20.into()),
     /// )
     /// ```
diff --git a/tests/constructors.rs b/tests/constructors.rs
index 9c9d080..9ff4e19 100644
--- a/tests/constructors.rs
+++ b/tests/constructors.rs
@@ -1,35 +1,24 @@
-use {
-    std::{borrow::Cow, sync::Arc},
-    text_size::*,
-};
+use text_size::TextSize;
 
 #[derive(Copy, Clone)]
 struct BadRope<'a>(&'a [&'a str]);
 
 impl BadRope<'_> {
     fn text_len(self) -> TextSize {
-        self.0.iter().map(TextSize::of).sum()
+        self.0.iter().copied().map(TextSize::of).sum()
     }
 }
 
 #[test]
 fn main() {
-    macro_rules! test {
-        ($($expr:expr),+ $(,)?) => {
-            $(let _ = TextSize::of($expr);)+
-        };
-    }
+    let x: char = 'c';
+    let _ = TextSize::of(x);
 
-    test! {
-        "",
-        &"",
-        'a',
-        &'a',
-        &String::new(),
-        &String::new().into_boxed_str(),
-        &Arc::new(String::new()),
-        &Cow::Borrowed(""),
-    }
+    let x: &str = "hello";
+    let _ = TextSize::of(x);
+
+    let x: &String = &"hello".into();
+    let _ = TextSize::of(x);
 
     let _ = BadRope(&[""]).text_len();
 }
diff --git a/tests/main.rs b/tests/main.rs
index f8eb6d6..5e6b86d 100644
--- a/tests/main.rs
+++ b/tests/main.rs
@@ -26,7 +26,7 @@
     assert_eq!(size(1).checked_add(size(1)), Some(size(2)));
     assert_eq!(size(1).checked_sub(size(1)), Some(size(0)));
     assert_eq!(size(1).checked_sub(size(2)), None);
-    assert_eq!(TextSize::MAX.checked_add(size(1)), None);
+    assert_eq!(size(!0).checked_add(size(1)), None);
 }
 
 #[test]