From f9c4ff475b959c49540324bde49e72c7feb9a654 Mon Sep 17 00:00:00 2001
From: KAMADA Ken'ichi <kamada@nanohz.org>
Date: Wed, 27 Mar 2019 23:16:05 +0900
Subject: [PATCH] Use u8::is_ascii_uppercase() stabilized in Rust 1.24.

---
 src/tag.rs  |  4 ++--
 src/util.rs | 15 ---------------
 2 files changed, 2 insertions(+), 17 deletions(-)

diff --git a/src/tag.rs b/src/tag.rs
index cb5bfe6..c7c6a7e 100644
--- a/src/tag.rs
+++ b/src/tag.rs
@@ -28,7 +28,7 @@ use std::fmt;
 
 use value;
 use value::Value;
-use util::{atou16, isupper};
+use util::atou16;
 
 /// A tag of a TIFF field.
 ///
@@ -1047,7 +1047,7 @@ fn d_gpsver(w: &mut fmt::Write, value: &Value) -> fmt::Result {
 fn d_gpslatlongref(w: &mut fmt::Write, value: &Value) -> fmt::Result {
     match *value {
         Value::Ascii(ref v) if (v.len() == 1 && v[0].len() == 1 &&
-                                isupper(v[0][0])) =>
+                                v[0][0].is_ascii_uppercase()) =>
             w.write_char(v[0][0] as char),
         _ => d_default(w, value),
     }
diff --git a/src/util.rs b/src/util.rs
index 7086e4a..51e498e 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -30,8 +30,6 @@ use error::Error;
 
 const ASCII_0: u8 = 0x30;
 const ASCII_9: u8 = 0x39;
-const ASCII_A: u8 = 0x41;
-const ASCII_Z: u8 = 0x5a;
 
 pub fn read8<R>(reader: &mut R) -> Result<u8, io::Error> where R: io::Read {
     let mut buf = [0u8; 1];
@@ -69,10 +67,6 @@ pub fn ctou32(c: u8) -> Result<u32, Error> {
     Ok((c - ASCII_0) as u32)
 }
 
-pub fn isupper(c: u8) -> bool {
-    ASCII_A <= c && c <= ASCII_Z
-}
-
 #[cfg(test)]
 mod tests {
     use std::io::Cursor;
@@ -118,13 +112,4 @@ mod tests {
         assert_err_pat!(atou16(b":"), Error::InvalidFormat(_));
         assert_err_pat!(atou16(b"-1"), Error::InvalidFormat(_));
     }
-
-    #[test]
-    fn isupper() {
-        assert!(super::isupper(b'A'));
-        assert!(super::isupper(b'Z'));
-        assert!(!super::isupper(b'A' - 1));
-        assert!(!super::isupper(b'Z' + 1));
-        assert!(!super::isupper(b'a'));
-    }
 }