Merge pull request #1058 from H2CO3/master

Reduce amount of unsafe code

.travis.yml

@@ -3,10 +3,10 @@ language: rust
 cache: cargo
 rust:
   - nightly
-  - nightly-2017-01-25
+  - nightly-2017-06-07
   - beta
   - stable
-  - 1.13.0
+  - 1.18.0
 matrix:
     allow_failures:
         - rust: nightly

src/app/help.rs

@@ -850,12 +850,11 @@ impl<'a> Help<'a> {
                 _ => continue,
             };
 
-            debugln!("Help::write_template_help:iter: tag_buf={};", unsafe {
-                String::from_utf8_unchecked(tag_buf.get_ref()[0..tag_length]
-                                                .iter()
-                                                .map(|&i| i)
-                                                .collect::<Vec<_>>())
-            });
+            debugln!(
+                "Help::write_template_help:iter: tag_buf={};",
+                str::from_utf8(&tag_buf.get_ref()[..tag_length])
+                    .unwrap_or_default()
+            );
             match &tag_buf.get_ref()[0..tag_length] {
                 b"?" => {
                     self.writer.write_all(b"Could not decode tag name")?;

src/app/parser.rs

@@ -1352,7 +1352,7 @@ impl<'a, 'b> Parser<'a, 'b>
         match Help::write_parser_help(&mut buf, self, use_long) {
             Err(e) => e,
             _ => Error {
-                message: unsafe { String::from_utf8_unchecked(buf) },
+                message: String::from_utf8(buf).unwrap_or_default(),
                 kind: ErrorKind::HelpDisplayed,
                 info: None,
             }
@@ -1566,7 +1566,7 @@ impl<'a, 'b> Parser<'a, 'b>
         if no_val && min_vals_zero && !has_eq && needs_eq {
             debugln!("Parser::parse_opt: More arg vals not required...");
             return Ok(ParseResult::ValuesDone);
-        } else if no_val || (mult && !needs_delim) && !has_eq && matcher.needs_more_vals(opt) { 
+        } else if no_val || (mult && !needs_delim) && !has_eq && matcher.needs_more_vals(opt) {
             debugln!("Parser::parse_opt: More arg vals required...");
             return Ok(ParseResult::Opt(opt.b.name));
         }

src/macros.rs

@@ -422,26 +422,29 @@ macro_rules! crate_authors {
         use std::sync::{ONCE_INIT, Once};
 
         #[allow(missing_copy_implementations)]
-        #[allow(non_camel_case_types)]
         #[allow(dead_code)]
-        struct CARGO_AUTHORS {__private_field: ()}
-        static CARGO_AUTHORS: CARGO_AUTHORS = CARGO_AUTHORS {__private_field: ()};
+        struct CargoAuthors { __private_field: () };
 
-        impl Deref for CARGO_AUTHORS {
-            type Target = String;
+        impl Deref for CargoAuthors {
+            type Target = str;
 
             #[allow(unsafe_code)]
-            fn deref<'a>(&'a self) -> &'a String {
-                unsafe {
-                    static mut LAZY: (*const String, Once) = (0 as *const String, ONCE_INIT);
+            fn deref(&self) -> &'static str {
+                static ONCE: Once = ONCE_INIT;
+                static mut VALUE: *const String = 0 as *const String;
 
-                    LAZY.1.call_once(|| LAZY.0 = Box::into_raw(Box::new(env!("CARGO_PKG_AUTHORS").replace(':', $sep))));
-                    &*LAZY.0
+                unsafe {
+                    ONCE.call_once(|| {
+                        let s = env!("CARGO_PKG_AUTHORS").replace(':', $sep);
+                        VALUE = Box::into_raw(Box::new(s));
+                    });
+
+                    &(*VALUE)[..]
                 }
             }
         }
 
-        &CARGO_AUTHORS[..]
+        &*CargoAuthors { __private_field: () }
     }};
     () => {
         env!("CARGO_PKG_AUTHORS")