Warn about 2018 idioms (#331)

Make sure we keep the code up-to-date!

Author: alexcrichton

benches/benchmarks.rs

@@ -2,8 +2,6 @@
 
 extern crate test;
 
-extern crate backtrace;
-
 #[cfg(feature = "std")]
 use backtrace::Backtrace;
 

examples/backtrace.rs

@@ -1,5 +1,3 @@
-extern crate backtrace;
-
 use backtrace::Backtrace;
 
 fn main() {

examples/raw.rs

@@ -1,5 +1,3 @@
-extern crate backtrace;
-
 fn main() {
     foo();
 }

src/backtrace/mod.rs

@@ -104,7 +104,7 @@ impl Frame {
 }
 
 impl fmt::Debug for Frame {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_struct("Frame")
             .field("ip", &self.ip())
             .field("symbol_address", &self.symbol_address())

src/capture.rs

@@ -289,7 +289,7 @@ impl BacktraceSymbol {
     ///
     /// This function requires the `std` feature of the `backtrace` crate to be
     /// enabled, and the `std` feature is enabled by default.
-    pub fn name(&self) -> Option<SymbolName> {
+    pub fn name(&self) -> Option<SymbolName<'_>> {
         self.name.as_ref().map(|s| SymbolName::new(s))
     }
 
@@ -325,7 +325,7 @@ impl BacktraceSymbol {
 }
 
 impl fmt::Debug for Backtrace {
-    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
         let full = fmt.alternate();
         let (frames, style) = if full {
             (&self.frames[..], PrintFmt::Full)
@@ -338,7 +338,7 @@ impl fmt::Debug for Backtrace {
         // short format, because if it's full we presumably want to print
         // everything.
         let cwd = std::env::current_dir();
-        let mut print_path = move |fmt: &mut fmt::Formatter, path: crate::BytesOrWideString| {
+        let mut print_path = move |fmt: &mut fmt::Formatter<'_>, path: crate::BytesOrWideString<'_>| {
             let path = path.into_path_buf();
             if !full {
                 if let Ok(cwd) = &cwd {
@@ -367,7 +367,7 @@ impl Default for Backtrace {
 }
 
 impl fmt::Debug for BacktraceFrame {
-    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
         fmt.debug_struct("BacktraceFrame")
             .field("ip", &self.ip())
             .field("symbol_address", &self.symbol_address())
@@ -376,7 +376,7 @@ impl fmt::Debug for BacktraceFrame {
 }
 
 impl fmt::Debug for BacktraceSymbol {
-    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
         fmt.debug_struct("BacktraceSymbol")
             .field("name", &self.name())
             .field("addr", &self.addr())

src/lib.rs

@@ -48,6 +48,7 @@
     all(feature = "std", target_env = "sgx", target_vendor = "fortanix"),
     feature(sgx_platform)
 )]
+#![warn(rust_2018_idioms)]
 
 #[cfg(feature = "std")]
 #[macro_use]

src/print.rs

@@ -16,7 +16,8 @@ pub struct BacktraceFmt<'a, 'b> {
     fmt: &'a mut fmt::Formatter<'b>,
     frame_index: usize,
     format: PrintFmt,
-    print_path: &'a mut (dyn FnMut(&mut fmt::Formatter, BytesOrWideString) -> fmt::Result + 'b),
+    print_path:
+        &'a mut (dyn FnMut(&mut fmt::Formatter<'_>, BytesOrWideString<'_>) -> fmt::Result + 'b),
 }
 
 /// The styles of printing that we can print
@@ -41,7 +42,8 @@ impl<'a, 'b> BacktraceFmt<'a, 'b> {
     pub fn new(
         fmt: &'a mut fmt::Formatter<'b>,
         format: PrintFmt,
-        print_path: &'a mut (dyn FnMut(&mut fmt::Formatter, BytesOrWideString) -> fmt::Result + 'b),
+        print_path: &'a mut (dyn FnMut(&mut fmt::Formatter<'_>, BytesOrWideString<'_>) -> fmt::Result
+                     + 'b),
     ) -> Self {
         BacktraceFmt {
             fmt,
@@ -160,8 +162,8 @@ impl BacktraceFrameFmt<'_, '_, '_> {
     pub fn print_raw(
         &mut self,
         frame_ip: *mut c_void,
-        symbol_name: Option<crate::SymbolName>,
-        filename: Option<BytesOrWideString>,
+        symbol_name: Option<crate::SymbolName<'_>>,
+        filename: Option<BytesOrWideString<'_>>,
         lineno: Option<u32>,
     ) -> fmt::Result {
         // Fuchsia is unable to symbolize within a process so it has a special
@@ -180,8 +182,8 @@ impl BacktraceFrameFmt<'_, '_, '_> {
     fn print_raw_generic(
         &mut self,
         mut frame_ip: *mut c_void,
-        symbol_name: Option<crate::SymbolName>,
-        filename: Option<BytesOrWideString>,
+        symbol_name: Option<crate::SymbolName<'_>>,
+        filename: Option<BytesOrWideString<'_>>,
         lineno: Option<u32>,
     ) -> fmt::Result {
         // No need to print "null" frames, it basically just means that the
@@ -234,7 +236,7 @@ impl BacktraceFrameFmt<'_, '_, '_> {
         Ok(())
     }
 
-    fn print_fileline(&mut self, file: BytesOrWideString, line: u32) -> fmt::Result {
+    fn print_fileline(&mut self, file: BytesOrWideString<'_>, line: u32) -> fmt::Result {
         // Filename/line are printed on lines under the symbol name, so print
         // some appropriate whitespace to sort of right-align ourselves.
         if let PrintFmt::Full = self.fmt.format {

src/symbolize/gimli.rs

@@ -467,13 +467,13 @@ impl Cache {
     }
 }
 
-pub unsafe fn resolve(what: ResolveWhat, cb: &mut dyn FnMut(&super::Symbol)) {
+pub unsafe fn resolve(what: ResolveWhat<'_>, cb: &mut dyn FnMut(&super::Symbol)) {
     let addr = what.address_or_ip();
-    let mut call = |sym: Symbol| {
+    let mut call = |sym: Symbol<'_>| {
         // Extend the lifetime of `sym` to `'static` since we are unfortunately
         // required to here, but it's ony ever going out as a reference so no
         // reference to it should be persisted beyond this frame anyway.
-        let sym = mem::transmute::<Symbol, Symbol<'static>>(sym);
+        let sym = mem::transmute::<Symbol<'_>, Symbol<'static>>(sym);
         (cb)(&super::Symbol { inner: sym });
     };
 
@@ -526,7 +526,7 @@ pub enum Symbol<'a> {
 }
 
 impl Symbol<'_> {
-    pub fn name(&self) -> Option<SymbolName> {
+    pub fn name(&self) -> Option<SymbolName<'_>> {
         match self {
             Symbol::Frame { name, .. } => {
                 let name = name.as_ref()?;
@@ -543,7 +543,7 @@ impl Symbol<'_> {
         }
     }
 
-    pub fn filename_raw(&self) -> Option<BytesOrWideString> {
+    pub fn filename_raw(&self) -> Option<BytesOrWideString<'_>> {
         match self {
             Symbol::Frame { location, .. } => {
                 let file = location.as_ref()?.file?;

src/symbolize/mod.rs

@@ -204,7 +204,7 @@ impl Symbol {
     /// * The raw `str` value of the symbol can be accessed (if it's valid
     ///   utf-8).
     /// * The raw bytes for the symbol name can be accessed.
-    pub fn name(&self) -> Option<SymbolName> {
+    pub fn name(&self) -> Option<SymbolName<'_>> {
         self.inner.name()
     }
 
@@ -215,7 +215,7 @@ impl Symbol {
 
     /// Returns the raw filename as a slice. This is mainly useful for `no_std`
     /// environments.
-    pub fn filename_raw(&self) -> Option<BytesOrWideString> {
+    pub fn filename_raw(&self) -> Option<BytesOrWideString<'_>> {
         self.inner.filename_raw()
     }
 
@@ -246,7 +246,7 @@ impl Symbol {
 }
 
 impl fmt::Debug for Symbol {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let mut d = f.debug_struct("Symbol");
         if let Some(name) = self.name() {
             d.field("name", &name);
@@ -349,9 +349,9 @@ impl<'a> SymbolName<'a> {
 }
 
 fn format_symbol_name(
-    fmt: fn(&str, &mut fmt::Formatter) -> fmt::Result,
+    fmt: fn(&str, &mut fmt::Formatter<'_>) -> fmt::Result,
     mut bytes: &[u8],
-    f: &mut fmt::Formatter,
+    f: &mut fmt::Formatter<'_>,
 ) -> fmt::Result {
     while bytes.len() > 0 {
         match str::from_utf8(bytes) {
@@ -387,7 +387,7 @@ cfg_if::cfg_if! {
         }
     } else {
         impl<'a> fmt::Display for SymbolName<'a> {
-            fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
                 if let Some(ref s) = self.demangled {
                     s.fmt(f)
                 } else {
@@ -423,7 +423,7 @@ cfg_if::cfg_if! {
         }
     } else {
         impl<'a> fmt::Debug for SymbolName<'a> {
-            fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
                 if let Some(ref s) = self.demangled {
                     s.fmt(f)
                 } else {

src/types.rs

@@ -77,7 +77,7 @@ impl<'a> BytesOrWideString<'a> {
 
 #[cfg(feature = "std")]
 impl<'a> fmt::Display for BytesOrWideString<'a> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         self.to_str_lossy().fmt(f)
     }
 }

tests/long_fn_name.rs

@@ -1,5 +1,3 @@
-extern crate backtrace;
-
 use backtrace::Backtrace;
 
 // 50-character module name

tests/skip_inner_frames.rs

@@ -1,5 +1,3 @@
-extern crate backtrace;
-
 use backtrace::Backtrace;
 
 // This test only works on platforms which have a working `symbol_address`

tests/smoke.rs

@@ -1,5 +1,3 @@
-extern crate backtrace;
-
 use backtrace::Frame;
 use std::thread;