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-rw-r--r--third_party/rust/quick-error/src/lib.rs1262
1 files changed, 1262 insertions, 0 deletions
diff --git a/third_party/rust/quick-error/src/lib.rs b/third_party/rust/quick-error/src/lib.rs
new file mode 100644
index 0000000000..17fc455d46
--- /dev/null
+++ b/third_party/rust/quick-error/src/lib.rs
@@ -0,0 +1,1262 @@
+#![warn(missing_docs)]
+//! A macro which makes errors easy to write
+//!
+//! Minimum type is like this:
+//!
+//! ```rust
+//! #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//!
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum SomeError {
+//! Variant1 {}
+//! }
+//! }
+//! ```
+//! Both ``pub`` and non-public types may be declared, and all meta attributes
+//! (such as ``#[derive(Debug)]``) are forwarded as is. The `Debug` must be
+//! implemented (but you may do that yourself if you like). The documentation
+//! comments ``/// something`` (as well as other meta attrbiutes) on variants
+//! are allowed.
+//!
+//! # Allowed Syntax
+//!
+//! You may add arbitrary parameters to any struct variant:
+//!
+//! ```rust
+//! # #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//! #
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum SomeError {
+//! /// IO Error
+//! Io(err: std::io::Error) {}
+//! /// Utf8 Error
+//! Utf8(err: std::str::Utf8Error) {}
+//! }
+//! }
+//! ```
+//!
+//! Note unlike in normal Enum declarations you declare names of fields (which
+//! are omitted from type). How they can be used is outlined below.
+//!
+//! Now you might have noticed trailing braces `{}`. They are used to define
+//! implementations. By default:
+//!
+//! * `Error::cause()` returns None (even if type wraps some value)
+//! * `Display` outputs debug representation
+//! * No `From` implementations are defined
+//!
+//! ```rust
+//! # #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//! #
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum SomeError {
+//! Io(err: std::io::Error) {
+//! display("{}", err)
+//! }
+//! Utf8(err: std::str::Utf8Error) {
+//! display("utf8 error")
+//! }
+//! }
+//! }
+//! ```
+//!
+//! To change `cause` method to return some error, add `cause(value)`, for
+//! example:
+//!
+//! ```rust
+//! # #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//! #
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum SomeError {
+//! Io(err: std::io::Error) {
+//! cause(err)
+//! }
+//! Utf8(err: std::str::Utf8Error) {
+//! display("utf8 error")
+//! }
+//! Other(err: Box<std::error::Error>) {
+//! cause(&**err)
+//! }
+//! }
+//! }
+//! ```
+//! Note you don't need to wrap value in `Some`, its implicit. In case you want
+//! `None` returned just omit the `cause`. You can't return `None`
+//! conditionally.
+//!
+//! To change how each clause is `Display`ed add `display(pattern,..args)`,
+//! for example:
+//!
+//! ```rust
+//! # #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//! #
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum SomeError {
+//! Io(err: std::io::Error) {
+//! display("I/O error: {}", err)
+//! }
+//! Utf8(err: std::str::Utf8Error) {
+//! display("Utf8 error, valid up to {}", err.valid_up_to())
+//! }
+//! }
+//! }
+//! ```
+//!
+//! If you need a reference to the error when `Display`ing, you can instead use
+//! `display(x) -> (pattern, ..args)`, where `x` sets the name of the reference.
+//!
+//! ```rust
+//! # #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//! #
+//! use std::error::Error; // put methods like `source()` of this trait into scope
+//!
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum SomeError {
+//! Io(err: std::io::Error) {
+//! display(x) -> ("I/O: {}", err)
+//! }
+//! Utf8(err: std::str::Utf8Error) {
+//! display(self_) -> ("UTF-8 error. Valid up to {}", err.valid_up_to())
+//! }
+//! }
+//! }
+//! ```
+//!
+//! To convert to the type from any other, use one of the three forms of
+//! `from` clause.
+//!
+//! For example, to convert simple wrapper use bare `from()`:
+//!
+//! ```rust
+//! # #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//! #
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum SomeError {
+//! Io(err: std::io::Error) {
+//! from()
+//! }
+//! }
+//! }
+//! ```
+//!
+//! This implements ``From<io::Error>``.
+//!
+//! To convert to singleton enumeration type (discarding the value), use
+//! the `from(type)` form:
+//!
+//! ```rust
+//! # #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//! #
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum SomeError {
+//! FormatError {
+//! from(std::fmt::Error)
+//! }
+//! }
+//! }
+//! ```
+//!
+//! And the most powerful form is `from(var: type) -> (arguments...)`. It
+//! might be used to convert to type with multiple arguments or for arbitrary
+//! value conversions:
+//!
+//! ```rust
+//! # #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//! #
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum SomeError {
+//! FailedOperation(s: &'static str, errno: i32) {
+//! from(errno: i32) -> ("os error", errno)
+//! from(e: std::io::Error) -> ("io error", e.raw_os_error().unwrap())
+//! }
+//! /// Converts from both kinds of utf8 errors
+//! Utf8(err: std::str::Utf8Error) {
+//! from()
+//! from(err: std::string::FromUtf8Error) -> (err.utf8_error())
+//! }
+//! }
+//! }
+//! ```
+//! # Context
+//!
+//! Since quick-error 1.1 we also have a `context` declaration, which is
+//! similar to (the longest form of) `from`, but allows adding some context to
+//! the error. We need a longer example to demonstrate this:
+//!
+//! ```rust
+//! # #[macro_use] extern crate quick_error;
+//! # use std::io;
+//! # use std::fs::File;
+//! # use std::path::{Path, PathBuf};
+//! #
+//! use quick_error::ResultExt;
+//!
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum Error {
+//! File(filename: PathBuf, err: io::Error) {
+//! context(path: &'a Path, err: io::Error)
+//! -> (path.to_path_buf(), err)
+//! }
+//! }
+//! }
+//!
+//! fn openfile(path: &Path) -> Result<(), Error> {
+//! try!(File::open(path).context(path));
+//!
+//! // If we didn't have context, the line above would be written as;
+//! //
+//! // try!(File::open(path)
+//! // .map_err(|err| Error::File(path.to_path_buf(), err)));
+//!
+//! Ok(())
+//! }
+//!
+//! # fn main() {
+//! # openfile(Path::new("/etc/somefile")).ok();
+//! # }
+//! ```
+//!
+//! Each `context(a: A, b: B)` clause implements
+//! `From<Context<A, B>> for Error`. Which means multiple `context` clauses
+//! are a subject to the normal coherence rules. Unfortunately, we can't
+//! provide full support of generics for the context, but you may either use a
+//! lifetime `'a` for references or `AsRef<Type>` (the latter means `A:
+//! AsRef<Type>`, and `Type` must be concrete). It's also occasionally useful
+//! to use a tuple as a type of the first argument.
+//!
+//! You also need to `use quick_error::ResultExt` extension trait to get
+//! working `.context()` method.
+//!
+//! More info on context in [this article](http://bit.ly/1PsuxDt).
+//!
+//! All forms of `from`, `display`, `cause`, and `context`
+//! clauses can be combined and put in arbitrary order. Only `from` and
+//! `context` can be used multiple times in single variant of enumeration.
+//! Docstrings are also okay. Empty braces can be omitted as of quick_error
+//! 0.1.3.
+//!
+//! # Private Enums
+//!
+//! Since quick-error 1.2.0 we have a way to make a private enum that is
+//! wrapped by public structure:
+//!
+//! ```rust
+//! #[macro_use] extern crate quick_error;
+//! # fn main() {}
+//!
+//! quick_error! {
+//! #[derive(Debug)]
+//! pub enum PubError wraps ErrorEnum {
+//! Variant1 {}
+//! }
+//! }
+//! ```
+//!
+//! This generates data structures like this
+//!
+//! ```rust
+//!
+//! pub struct PubError(ErrorEnum);
+//!
+//! enum ErrorEnum {
+//! Variant1,
+//! }
+//!
+//! ```
+//!
+//! Which in turn allows you to export just `PubError` in your crate and keep
+//! actual enumeration private to the crate. This is useful to keep backwards
+//! compatibility for error types. Currently there is no shorcuts to define
+//! error constructors for the inner type, but we consider adding some in
+//! future versions.
+//!
+//! It's possible to declare internal enum as public too.
+//!
+//!
+
+
+/// Main macro that does all the work
+#[macro_export]
+macro_rules! quick_error {
+
+ ( $(#[$meta:meta])*
+ pub enum $name:ident { $($chunks:tt)* }
+ ) => {
+ quick_error!(SORT [pub enum $name $(#[$meta])* ]
+ items [] buf []
+ queue [ $($chunks)* ]);
+ };
+ ( $(#[$meta:meta])*
+ enum $name:ident { $($chunks:tt)* }
+ ) => {
+ quick_error!(SORT [enum $name $(#[$meta])* ]
+ items [] buf []
+ queue [ $($chunks)* ]);
+ };
+
+ ( $(#[$meta:meta])*
+ pub enum $name:ident wraps $enum_name:ident { $($chunks:tt)* }
+ ) => {
+ quick_error!(WRAPPER $enum_name [ pub struct ] $name $(#[$meta])*);
+ quick_error!(SORT [enum $enum_name $(#[$meta])* ]
+ items [] buf []
+ queue [ $($chunks)* ]);
+ };
+
+ ( $(#[$meta:meta])*
+ pub enum $name:ident wraps pub $enum_name:ident { $($chunks:tt)* }
+ ) => {
+ quick_error!(WRAPPER $enum_name [ pub struct ] $name $(#[$meta])*);
+ quick_error!(SORT [pub enum $enum_name $(#[$meta])* ]
+ items [] buf []
+ queue [ $($chunks)* ]);
+ };
+ ( $(#[$meta:meta])*
+ enum $name:ident wraps $enum_name:ident { $($chunks:tt)* }
+ ) => {
+ quick_error!(WRAPPER $enum_name [ struct ] $name $(#[$meta])*);
+ quick_error!(SORT [enum $enum_name $(#[$meta])* ]
+ items [] buf []
+ queue [ $($chunks)* ]);
+ };
+
+ ( $(#[$meta:meta])*
+ enum $name:ident wraps pub $enum_name:ident { $($chunks:tt)* }
+ ) => {
+ quick_error!(WRAPPER $enum_name [ struct ] $name $(#[$meta])*);
+ quick_error!(SORT [pub enum $enum_name $(#[$meta])* ]
+ items [] buf []
+ queue [ $($chunks)* ]);
+ };
+
+
+ (
+ WRAPPER $internal:ident [ $($strdef:tt)* ] $strname:ident
+ $(#[$meta:meta])*
+ ) => {
+ $(#[$meta])*
+ $($strdef)* $strname ( $internal );
+
+ impl ::std::fmt::Display for $strname {
+ fn fmt(&self, f: &mut ::std::fmt::Formatter)
+ -> ::std::fmt::Result
+ {
+ ::std::fmt::Display::fmt(&self.0, f)
+ }
+ }
+
+ impl From<$internal> for $strname {
+ fn from(err: $internal) -> Self {
+ $strname(err)
+ }
+ }
+
+ impl ::std::error::Error for $strname {
+ #[allow(deprecated)]
+ fn cause(&self) -> Option<&::std::error::Error> {
+ self.0.cause()
+ }
+ }
+ };
+
+ // Queue is empty, can do the work
+ (SORT [enum $name:ident $( #[$meta:meta] )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [ ]
+ queue [ ]
+ ) => {
+ quick_error!(ENUM_DEFINITION [enum $name $( #[$meta] )*]
+ body []
+ queue [$($( #[$imeta] )*
+ => $iitem: $imode [$( $ivar: $ityp ),*] )*]
+ );
+ quick_error!(IMPLEMENTATIONS $name {$(
+ $iitem: $imode [$(#[$imeta])*] [$( $ivar: $ityp ),*] {$( $ifuncs )*}
+ )*});
+ $(
+ quick_error!(ERROR_CHECK $imode $($ifuncs)*);
+ )*
+ };
+ (SORT [pub enum $name:ident $( #[$meta:meta] )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [ ]
+ queue [ ]
+ ) => {
+ quick_error!(ENUM_DEFINITION [pub enum $name $( #[$meta] )*]
+ body []
+ queue [$($( #[$imeta] )*
+ => $iitem: $imode [$( $ivar: $ityp ),*] )*]
+ );
+ quick_error!(IMPLEMENTATIONS $name {$(
+ $iitem: $imode [$(#[$imeta])*] [$( $ivar: $ityp ),*] {$( $ifuncs )*}
+ )*});
+ $(
+ quick_error!(ERROR_CHECK $imode $($ifuncs)*);
+ )*
+ };
+ // Add meta to buffer
+ (SORT [$( $def:tt )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [$( #[$bmeta:meta] )*]
+ queue [ #[$qmeta:meta] $( $tail:tt )*]
+ ) => {
+ quick_error!(SORT [$( $def )*]
+ items [$( $(#[$imeta])* => $iitem: $imode [$( $ivar:$ityp ),*] {$( $ifuncs )*} )*]
+ buf [$( #[$bmeta] )* #[$qmeta] ]
+ queue [$( $tail )*]);
+ };
+ // Add ident to buffer
+ (SORT [$( $def:tt )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [$( #[$bmeta:meta] )*]
+ queue [ $qitem:ident $( $tail:tt )*]
+ ) => {
+ quick_error!(SORT [$( $def )*]
+ items [$( $(#[$imeta])*
+ => $iitem: $imode [$( $ivar:$ityp ),*] {$( $ifuncs )*} )*]
+ buf [$(#[$bmeta])* => $qitem : UNIT [ ] ]
+ queue [$( $tail )*]);
+ };
+ // Flush buffer on meta after ident
+ (SORT [$( $def:tt )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [$( #[$bmeta:meta] )*
+ => $bitem:ident: $bmode:tt [$( $bvar:ident: $btyp:ty ),*] ]
+ queue [ #[$qmeta:meta] $( $tail:tt )*]
+ ) => {
+ quick_error!(SORT [$( $def )*]
+ enum [$( $(#[$emeta])* => $eitem $(( $($etyp),* ))* )*
+ $(#[$bmeta])* => $bitem: $bmode $(( $($btyp),* ))*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem: $imode [$( $ivar:$ityp ),*] {$( $ifuncs )*} )*
+ $bitem: $bmode [$( $bvar:$btyp ),*] {} ]
+ buf [ #[$qmeta] ]
+ queue [$( $tail )*]);
+ };
+ // Add tuple enum-variant
+ (SORT [$( $def:tt )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [$( #[$bmeta:meta] )* => $bitem:ident: UNIT [ ] ]
+ queue [($( $qvar:ident: $qtyp:ty ),+) $( $tail:tt )*]
+ ) => {
+ quick_error!(SORT [$( $def )*]
+ items [$( $(#[$imeta])* => $iitem: $imode [$( $ivar:$ityp ),*] {$( $ifuncs )*} )*]
+ buf [$( #[$bmeta] )* => $bitem: TUPLE [$( $qvar:$qtyp ),*] ]
+ queue [$( $tail )*]
+ );
+ };
+ // Add struct enum-variant - e.g. { descr: &'static str }
+ (SORT [$( $def:tt )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [$( #[$bmeta:meta] )* => $bitem:ident: UNIT [ ] ]
+ queue [{ $( $qvar:ident: $qtyp:ty ),+} $( $tail:tt )*]
+ ) => {
+ quick_error!(SORT [$( $def )*]
+ items [$( $(#[$imeta])* => $iitem: $imode [$( $ivar:$ityp ),*] {$( $ifuncs )*} )*]
+ buf [$( #[$bmeta] )* => $bitem: STRUCT [$( $qvar:$qtyp ),*] ]
+ queue [$( $tail )*]);
+ };
+ // Add struct enum-variant, with excess comma - e.g. { descr: &'static str, }
+ (SORT [$( $def:tt )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [$( #[$bmeta:meta] )* => $bitem:ident: UNIT [ ] ]
+ queue [{$( $qvar:ident: $qtyp:ty ),+ ,} $( $tail:tt )*]
+ ) => {
+ quick_error!(SORT [$( $def )*]
+ items [$( $(#[$imeta])* => $iitem: $imode [$( $ivar:$ityp ),*] {$( $ifuncs )*} )*]
+ buf [$( #[$bmeta] )* => $bitem: STRUCT [$( $qvar:$qtyp ),*] ]
+ queue [$( $tail )*]);
+ };
+ // Add braces and flush always on braces
+ (SORT [$( $def:tt )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [$( #[$bmeta:meta] )*
+ => $bitem:ident: $bmode:tt [$( $bvar:ident: $btyp:ty ),*] ]
+ queue [ {$( $qfuncs:tt )*} $( $tail:tt )*]
+ ) => {
+ quick_error!(SORT [$( $def )*]
+ items [$( $(#[$imeta])* => $iitem: $imode [$( $ivar:$ityp ),*] {$( $ifuncs )*} )*
+ $(#[$bmeta])* => $bitem: $bmode [$( $bvar:$btyp ),*] {$( $qfuncs )*} ]
+ buf [ ]
+ queue [$( $tail )*]);
+ };
+ // Flush buffer on double ident
+ (SORT [$( $def:tt )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [$( #[$bmeta:meta] )*
+ => $bitem:ident: $bmode:tt [$( $bvar:ident: $btyp:ty ),*] ]
+ queue [ $qitem:ident $( $tail:tt )*]
+ ) => {
+ quick_error!(SORT [$( $def )*]
+ items [$( $(#[$imeta])* => $iitem: $imode [$( $ivar:$ityp ),*] {$( $ifuncs )*} )*
+ $(#[$bmeta])* => $bitem: $bmode [$( $bvar:$btyp ),*] {} ]
+ buf [ => $qitem : UNIT [ ] ]
+ queue [$( $tail )*]);
+ };
+ // Flush buffer on end
+ (SORT [$( $def:tt )*]
+ items [$($( #[$imeta:meta] )*
+ => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
+ {$( $ifuncs:tt )*} )* ]
+ buf [$( #[$bmeta:meta] )*
+ => $bitem:ident: $bmode:tt [$( $bvar:ident: $btyp:ty ),*] ]
+ queue [ ]
+ ) => {
+ quick_error!(SORT [$( $def )*]
+ items [$( $(#[$imeta])* => $iitem: $imode [$( $ivar:$ityp ),*] {$( $ifuncs )*} )*
+ $(#[$bmeta])* => $bitem: $bmode [$( $bvar:$btyp ),*] {} ]
+ buf [ ]
+ queue [ ]);
+ };
+ // Public enum (Queue Empty)
+ (ENUM_DEFINITION [pub enum $name:ident $( #[$meta:meta] )*]
+ body [$($( #[$imeta:meta] )*
+ => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
+ queue [ ]
+ ) => {
+ #[allow(unknown_lints)] // no unused_doc_comments in older rust
+ #[allow(renamed_and_removed_lints)]
+ #[allow(unused_doc_comment)]
+ #[allow(unused_doc_comments)]
+ $(#[$meta])*
+ pub enum $name {
+ $(
+ $(#[$imeta])*
+ $iitem $(($( $ttyp ),*))* $({$( $svar: $styp ),*})*,
+ )*
+ }
+ };
+ // Private enum (Queue Empty)
+ (ENUM_DEFINITION [enum $name:ident $( #[$meta:meta] )*]
+ body [$($( #[$imeta:meta] )*
+ => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
+ queue [ ]
+ ) => {
+ #[allow(unknown_lints)] // no unused_doc_comments in older rust
+ #[allow(renamed_and_removed_lints)]
+ #[allow(unused_doc_comment)]
+ #[allow(unused_doc_comments)]
+ $(#[$meta])*
+ enum $name {
+ $(
+ $(#[$imeta])*
+ $iitem $(($( $ttyp ),*))* $({$( $svar: $styp ),*})*,
+ )*
+ }
+ };
+ // Unit variant
+ (ENUM_DEFINITION [$( $def:tt )*]
+ body [$($( #[$imeta:meta] )*
+ => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
+ queue [$( #[$qmeta:meta] )*
+ => $qitem:ident: UNIT [ ] $( $queue:tt )*]
+ ) => {
+ quick_error!(ENUM_DEFINITION [ $($def)* ]
+ body [$($( #[$imeta] )* => $iitem ($(($( $ttyp ),+))*) {$({$( $svar: $styp ),*})*} )*
+ $( #[$qmeta] )* => $qitem () {} ]
+ queue [ $($queue)* ]
+ );
+ };
+ // Tuple variant
+ (ENUM_DEFINITION [$( $def:tt )*]
+ body [$($( #[$imeta:meta] )*
+ => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
+ queue [$( #[$qmeta:meta] )*
+ => $qitem:ident: TUPLE [$( $qvar:ident: $qtyp:ty ),+] $( $queue:tt )*]
+ ) => {
+ quick_error!(ENUM_DEFINITION [ $($def)* ]
+ body [$($( #[$imeta] )* => $iitem ($(($( $ttyp ),+))*) {$({$( $svar: $styp ),*})*} )*
+ $( #[$qmeta] )* => $qitem (($( $qtyp ),*)) {} ]
+ queue [ $($queue)* ]
+ );
+ };
+ // Struct variant
+ (ENUM_DEFINITION [$( $def:tt )*]
+ body [$($( #[$imeta:meta] )*
+ => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
+ queue [$( #[$qmeta:meta] )*
+ => $qitem:ident: STRUCT [$( $qvar:ident: $qtyp:ty ),*] $( $queue:tt )*]
+ ) => {
+ quick_error!(ENUM_DEFINITION [ $($def)* ]
+ body [$($( #[$imeta] )* => $iitem ($(($( $ttyp ),+))*) {$({$( $svar: $styp ),*})*} )*
+ $( #[$qmeta] )* => $qitem () {{$( $qvar: $qtyp ),*}} ]
+ queue [ $($queue)* ]
+ );
+ };
+ (IMPLEMENTATIONS
+ $name:ident {$(
+ $item:ident: $imode:tt [$(#[$imeta:meta])*] [$( $var:ident: $typ:ty ),*] {$( $funcs:tt )*}
+ )*}
+ ) => {
+ #[allow(unused)]
+ #[allow(unknown_lints)] // no unused_doc_comments in older rust
+ #[allow(renamed_and_removed_lints)]
+ #[allow(unused_doc_comment)]
+ #[allow(unused_doc_comments)]
+ impl ::std::fmt::Display for $name {
+ fn fmt(&self, fmt: &mut ::std::fmt::Formatter)
+ -> ::std::fmt::Result
+ {
+ match *self {
+ $(
+ $(#[$imeta])*
+ quick_error!(ITEM_PATTERN
+ $name $item: $imode [$( ref $var ),*]
+ ) => {
+ let display_fn = quick_error!(FIND_DISPLAY_IMPL
+ $name $item: $imode
+ {$( $funcs )*});
+
+ display_fn(self, fmt)
+ }
+ )*
+ }
+ }
+ }
+ #[allow(unused)]
+ #[allow(unknown_lints)] // no unused_doc_comments in older rust
+ #[allow(renamed_and_removed_lints)]
+ #[allow(unused_doc_comment)]
+ #[allow(unused_doc_comments)]
+ impl ::std::error::Error for $name {
+ fn cause(&self) -> Option<&::std::error::Error> {
+ match *self {
+ $(
+ $(#[$imeta])*
+ quick_error!(ITEM_PATTERN
+ $name $item: $imode [$( ref $var ),*]
+ ) => {
+ quick_error!(FIND_CAUSE_IMPL
+ $item: $imode [$( $var ),*]
+ {$( $funcs )*})
+ }
+ )*
+ }
+ }
+ }
+ $(
+ quick_error!(FIND_FROM_IMPL
+ $name $item: $imode [$( $var:$typ ),*]
+ {$( $funcs )*});
+ )*
+ $(
+ quick_error!(FIND_CONTEXT_IMPL
+ $name $item: $imode [$( $var:$typ ),*]
+ {$( $funcs )*});
+ )*
+ };
+ (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
+ { display($self_:tt) -> ($( $exprs:tt )*) $( $tail:tt )*}
+ ) => {
+ |quick_error!(IDENT $self_): &$name, f: &mut ::std::fmt::Formatter| { write!(f, $( $exprs )*) }
+ };
+ (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
+ { display($pattern:expr) $( $tail:tt )*}
+ ) => {
+ |_, f: &mut ::std::fmt::Formatter| { write!(f, $pattern) }
+ };
+ (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
+ { display($pattern:expr, $( $exprs:tt )*) $( $tail:tt )*}
+ ) => {
+ |_, f: &mut ::std::fmt::Formatter| { write!(f, $pattern, $( $exprs )*) }
+ };
+ (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
+ { $t:tt $( $tail:tt )*}
+ ) => {
+ quick_error!(FIND_DISPLAY_IMPL
+ $name $item: $imode
+ {$( $tail )*})
+ };
+ (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
+ { }
+ ) => {
+ |self_: &$name, f: &mut ::std::fmt::Formatter| {
+ write!(f, "{:?}", self_)
+ }
+ };
+ (FIND_DESCRIPTION_IMPL $item:ident: $imode:tt $me:ident $fmt:ident
+ [$( $var:ident ),*]
+ { description($expr:expr) $( $tail:tt )*}
+ ) => {};
+ (FIND_DESCRIPTION_IMPL $item:ident: $imode:tt $me:ident $fmt:ident
+ [$( $var:ident ),*]
+ { $t:tt $( $tail:tt )*}
+ ) => {};
+ (FIND_DESCRIPTION_IMPL $item:ident: $imode:tt $me:ident $fmt:ident
+ [$( $var:ident ),*]
+ { }
+ ) => {};
+ (FIND_CAUSE_IMPL $item:ident: $imode:tt
+ [$( $var:ident ),*]
+ { cause($expr:expr) $( $tail:tt )*}
+ ) => {
+ Some($expr)
+ };
+ (FIND_CAUSE_IMPL $item:ident: $imode:tt
+ [$( $var:ident ),*]
+ { $t:tt $( $tail:tt )*}
+ ) => {
+ quick_error!(FIND_CAUSE_IMPL
+ $item: $imode [$( $var ),*]
+ { $($tail)* })
+ };
+ (FIND_CAUSE_IMPL $item:ident: $imode:tt
+ [$( $var:ident ),*]
+ { }
+ ) => {
+ None
+ };
+ // ----------------------------- FROM IMPL --------------------------
+ (FIND_FROM_IMPL $name:ident $item:ident: $imode:tt
+ [$( $var:ident: $typ:ty ),*]
+ { from() $( $tail:tt )*}
+ ) => {
+ $(
+ impl From<$typ> for $name {
+ fn from($var: $typ) -> $name {
+ $name::$item($var)
+ }
+ }
+ )*
+ quick_error!(FIND_FROM_IMPL
+ $name $item: $imode [$( $var:$typ ),*]
+ {$( $tail )*});
+ };
+ (FIND_FROM_IMPL $name:ident $item:ident: UNIT
+ [ ]
+ { from($ftyp:ty) $( $tail:tt )*}
+ ) => {
+ impl From<$ftyp> for $name {
+ fn from(_discarded_error: $ftyp) -> $name {
+ $name::$item
+ }
+ }
+ quick_error!(FIND_FROM_IMPL
+ $name $item: UNIT [ ]
+ {$( $tail )*});
+ };
+ (FIND_FROM_IMPL $name:ident $item:ident: TUPLE
+ [$( $var:ident: $typ:ty ),*]
+ { from($fvar:ident: $ftyp:ty) -> ($( $texpr:expr ),*) $( $tail:tt )*}
+ ) => {
+ impl From<$ftyp> for $name {
+ fn from($fvar: $ftyp) -> $name {
+ $name::$item($( $texpr ),*)
+ }
+ }
+ quick_error!(FIND_FROM_IMPL
+ $name $item: TUPLE [$( $var:$typ ),*]
+ { $($tail)* });
+ };
+ (FIND_FROM_IMPL $name:ident $item:ident: STRUCT
+ [$( $var:ident: $typ:ty ),*]
+ { from($fvar:ident: $ftyp:ty) -> {$( $tvar:ident: $texpr:expr ),*} $( $tail:tt )*}
+ ) => {
+ impl From<$ftyp> for $name {
+ fn from($fvar: $ftyp) -> $name {
+ $name::$item {
+ $( $tvar: $texpr ),*
+ }
+ }
+ }
+ quick_error!(FIND_FROM_IMPL
+ $name $item: STRUCT [$( $var:$typ ),*]
+ { $($tail)* });
+ };
+ (FIND_FROM_IMPL $name:ident $item:ident: $imode:tt
+ [$( $var:ident: $typ:ty ),*]
+ { $t:tt $( $tail:tt )*}
+ ) => {
+ quick_error!(FIND_FROM_IMPL
+ $name $item: $imode [$( $var:$typ ),*]
+ {$( $tail )*}
+ );
+ };
+ (FIND_FROM_IMPL $name:ident $item:ident: $imode:tt
+ [$( $var:ident: $typ:ty ),*]
+ { }
+ ) => {
+ };
+ // ----------------------------- CONTEXT IMPL --------------------------
+ (FIND_CONTEXT_IMPL $name:ident $item:ident: TUPLE
+ [$( $var:ident: $typ:ty ),*]
+ { context($cvar:ident: AsRef<$ctyp:ty>, $fvar:ident: $ftyp:ty)
+ -> ($( $texpr:expr ),*) $( $tail:tt )* }
+ ) => {
+ impl<T: AsRef<$ctyp>> From<$crate::Context<T, $ftyp>> for $name {
+ fn from(
+ $crate::Context($cvar, $fvar): $crate::Context<T, $ftyp>)
+ -> $name
+ {
+ $name::$item($( $texpr ),*)
+ }
+ }
+ quick_error!(FIND_CONTEXT_IMPL
+ $name $item: TUPLE [$( $var:$typ ),*]
+ { $($tail)* });
+ };
+ (FIND_CONTEXT_IMPL $name:ident $item:ident: TUPLE
+ [$( $var:ident: $typ:ty ),*]
+ { context($cvar:ident: $ctyp:ty, $fvar:ident: $ftyp:ty)
+ -> ($( $texpr:expr ),*) $( $tail:tt )* }
+ ) => {
+ impl<'a> From<$crate::Context<$ctyp, $ftyp>> for $name {
+ fn from(
+ $crate::Context($cvar, $fvar): $crate::Context<$ctyp, $ftyp>)
+ -> $name
+ {
+ $name::$item($( $texpr ),*)
+ }
+ }
+ quick_error!(FIND_CONTEXT_IMPL
+ $name $item: TUPLE [$( $var:$typ ),*]
+ { $($tail)* });
+ };
+ (FIND_CONTEXT_IMPL $name:ident $item:ident: STRUCT
+ [$( $var:ident: $typ:ty ),*]
+ { context($cvar:ident: AsRef<$ctyp:ty>, $fvar:ident: $ftyp:ty)
+ -> {$( $tvar:ident: $texpr:expr ),*} $( $tail:tt )* }
+ ) => {
+ impl<T: AsRef<$ctyp>> From<$crate::Context<T, $ftyp>> for $name {
+ fn from(
+ $crate::Context($cvar, $fvar): $crate::Context<$ctyp, $ftyp>)
+ -> $name
+ {
+ $name::$item {
+ $( $tvar: $texpr ),*
+ }
+ }
+ }
+ quick_error!(FIND_CONTEXT_IMPL
+ $name $item: STRUCT [$( $var:$typ ),*]
+ { $($tail)* });
+ };
+ (FIND_CONTEXT_IMPL $name:ident $item:ident: STRUCT
+ [$( $var:ident: $typ:ty ),*]
+ { context($cvar:ident: $ctyp:ty, $fvar:ident: $ftyp:ty)
+ -> {$( $tvar:ident: $texpr:expr ),*} $( $tail:tt )* }
+ ) => {
+ impl<'a> From<$crate::Context<$ctyp, $ftyp>> for $name {
+ fn from(
+ $crate::Context($cvar, $fvar): $crate::Context<$ctyp, $ftyp>)
+ -> $name
+ {
+ $name::$item {
+ $( $tvar: $texpr ),*
+ }
+ }
+ }
+ quick_error!(FIND_CONTEXT_IMPL
+ $name $item: STRUCT [$( $var:$typ ),*]
+ { $($tail)* });
+ };
+ (FIND_CONTEXT_IMPL $name:ident $item:ident: $imode:tt
+ [$( $var:ident: $typ:ty ),*]
+ { $t:tt $( $tail:tt )*}
+ ) => {
+ quick_error!(FIND_CONTEXT_IMPL
+ $name $item: $imode [$( $var:$typ ),*]
+ {$( $tail )*}
+ );
+ };
+ (FIND_CONTEXT_IMPL $name:ident $item:ident: $imode:tt
+ [$( $var:ident: $typ:ty ),*]
+ { }
+ ) => {
+ };
+ // ----------------------------- ITEM IMPL --------------------------
+ (ITEM_BODY $(#[$imeta:meta])* $item:ident: UNIT
+ ) => { };
+ (ITEM_BODY $(#[$imeta:meta])* $item:ident: TUPLE
+ [$( $typ:ty ),*]
+ ) => {
+ ($( $typ ),*)
+ };
+ (ITEM_BODY $(#[$imeta:meta])* $item:ident: STRUCT
+ [$( $var:ident: $typ:ty ),*]
+ ) => {
+ {$( $var:$typ ),*}
+ };
+ (ITEM_PATTERN $name:ident $item:ident: UNIT []
+ ) => {
+ $name::$item
+ };
+ (ITEM_PATTERN $name:ident $item:ident: TUPLE
+ [$( ref $var:ident ),*]
+ ) => {
+ $name::$item ($( ref $var ),*)
+ };
+ (ITEM_PATTERN $name:ident $item:ident: STRUCT
+ [$( ref $var:ident ),*]
+ ) => {
+ $name::$item {$( ref $var ),*}
+ };
+ // This one should match all allowed sequences in "funcs" but not match
+ // anything else.
+ // This is to contrast FIND_* clauses which just find stuff they need and
+ // skip everything else completely
+ (ERROR_CHECK $imode:tt display($self_:tt) -> ($( $exprs:tt )*) $( $tail:tt )*)
+ => { quick_error!(ERROR_CHECK $imode $($tail)*); };
+ (ERROR_CHECK $imode:tt display($pattern: expr) $( $tail:tt )*)
+ => { quick_error!(ERROR_CHECK $imode $($tail)*); };
+ (ERROR_CHECK $imode:tt display($pattern: expr, $( $exprs:tt )*) $( $tail:tt )*)
+ => { quick_error!(ERROR_CHECK $imode $($tail)*); };
+ (ERROR_CHECK $imode:tt description($expr:expr) $( $tail:tt )*)
+ => { quick_error!(ERROR_CHECK $imode $($tail)*); };
+ (ERROR_CHECK $imode:tt cause($expr:expr) $($tail:tt)*)
+ => { quick_error!(ERROR_CHECK $imode $($tail)*); };
+ (ERROR_CHECK $imode:tt from() $($tail:tt)*)
+ => { quick_error!(ERROR_CHECK $imode $($tail)*); };
+ (ERROR_CHECK $imode:tt from($ftyp:ty) $($tail:tt)*)
+ => { quick_error!(ERROR_CHECK $imode $($tail)*); };
+ (ERROR_CHECK TUPLE from($fvar:ident: $ftyp:ty) -> ($( $e:expr ),*) $( $tail:tt )*)
+ => { quick_error!(ERROR_CHECK TUPLE $($tail)*); };
+ (ERROR_CHECK STRUCT from($fvar:ident: $ftyp:ty) -> {$( $v:ident: $e:expr ),*} $( $tail:tt )*)
+ => { quick_error!(ERROR_CHECK STRUCT $($tail)*); };
+
+ (ERROR_CHECK TUPLE context($cvar:ident: $ctyp:ty, $fvar:ident: $ftyp:ty)
+ -> ($( $e:expr ),*) $( $tail:tt )*)
+ => { quick_error!(ERROR_CHECK TUPLE $($tail)*); };
+ (ERROR_CHECK STRUCT context($cvar:ident: $ctyp:ty, $fvar:ident: $ftyp:ty)
+ -> {$( $v:ident: $e:expr ),*} $( $tail:tt )*)
+ => { quick_error!(ERROR_CHECK STRUCT $($tail)*); };
+
+ (ERROR_CHECK $imode:tt ) => {};
+ // Utility functions
+ (IDENT $ident:ident) => { $ident }
+}
+
+
+/// Generic context type
+///
+/// Used mostly as a transport for `ResultExt::context` method
+#[derive(Debug)]
+pub struct Context<X, E>(pub X, pub E);
+
+/// Result extension trait adding a `context` method
+pub trait ResultExt<T, E> {
+ /// The method is use to add context information to current operation
+ ///
+ /// The context data is then used in error constructor to store additional
+ /// information within error. For example, you may add a filename as a
+ /// context for file operation. See crate documentation for the actual
+ /// example.
+ fn context<X>(self, x: X) -> Result<T, Context<X, E>>;
+}
+
+impl<T, E> ResultExt<T, E> for Result<T, E> {
+ fn context<X>(self, x: X) -> Result<T, Context<X, E>> {
+ self.map_err(|e| Context(x, e))
+ }
+}
+
+
+
+#[cfg(test)]
+#[allow(deprecated)]
+mod test {
+ use std::num::{ParseFloatError, ParseIntError};
+ use std::str::Utf8Error;
+ use std::string::FromUtf8Error;
+ use std::error::Error;
+ use std::path::{Path, PathBuf};
+
+ use super::ResultExt;
+
+ quick_error! {
+ #[derive(Debug)]
+ pub enum Bare {
+ One
+ Two
+ }
+ }
+
+ #[test]
+ fn bare_item_direct() {
+ assert_eq!(format!("{}", Bare::One), "One".to_string());
+ assert_eq!(format!("{:?}", Bare::One), "One".to_string());
+ assert!(Bare::One.cause().is_none());
+ }
+ #[test]
+ fn bare_item_trait() {
+ let err: &Error = &Bare::Two;
+ assert_eq!(format!("{}", err), "Two".to_string());
+ assert_eq!(format!("{:?}", err), "Two".to_string());
+ assert!(err.cause().is_none());
+ }
+
+ quick_error! {
+ #[derive(Debug)]
+ pub enum Wrapper wraps Wrapped {
+ One
+ Two(s: String) {
+ display("two: {}", s)
+ from()
+ }
+ }
+ }
+
+ #[test]
+ fn wrapper() {
+ assert_eq!(format!("{}", Wrapper::from(Wrapped::One)),
+ "One".to_string());
+ assert_eq!(format!("{}",
+ Wrapper::from(Wrapped::from(String::from("hello")))),
+ "two: hello".to_string());
+ assert_eq!(format!("{:?}", Wrapper::from(Wrapped::One)),
+ "Wrapper(One)".to_string());
+ }
+
+ quick_error! {
+ #[derive(Debug, PartialEq)]
+ pub enum TupleWrapper {
+ /// ParseFloat Error
+ ParseFloatError(err: ParseFloatError) {
+ from()
+ display("parse float error: {err}", err=err)
+ cause(err)
+ }
+ Other(descr: &'static str) {
+ display("Error: {}", descr)
+ }
+ /// FromUtf8 Error
+ FromUtf8Error(err: Utf8Error, source: Vec<u8>) {
+ cause(err)
+ display(me) -> ("{desc} at index {pos}: {err}", desc="utf8 error", pos=err.valid_up_to(), err=err)
+ from(err: FromUtf8Error) -> (err.utf8_error().clone(), err.into_bytes())
+ }
+ Discard {
+ from(&'static str)
+ }
+ Singleton {
+ display("Just a string")
+ }
+ }
+ }
+
+ #[test]
+ fn tuple_wrapper_err() {
+ let cause = "one and a half times pi".parse::<f32>().unwrap_err();
+ let err = TupleWrapper::ParseFloatError(cause.clone());
+ assert_eq!(format!("{}", err), format!("parse float error: {}", cause));
+ assert_eq!(format!("{:?}", err), format!("ParseFloatError({:?})", cause));
+ assert_eq!(format!("{:?}", err.cause().unwrap()), format!("{:?}", cause));
+ }
+
+ #[test]
+ fn tuple_wrapper_trait_str() {
+ let desc = "hello";
+ let err: &Error = &TupleWrapper::Other(desc);
+ assert_eq!(format!("{}", err), format!("Error: {}", desc));
+ assert_eq!(format!("{:?}", err), format!("Other({:?})", desc));
+ assert!(err.cause().is_none());
+ }
+
+ #[test]
+ fn tuple_wrapper_trait_two_fields() {
+ let invalid_utf8: Vec<u8> = vec![0, 159, 146, 150];
+ let cause = String::from_utf8(invalid_utf8.clone()).unwrap_err().utf8_error();
+ let err: &Error = &TupleWrapper::FromUtf8Error(cause.clone(), invalid_utf8.clone());
+ assert_eq!(format!("{}", err), format!("{desc} at index {pos}: {cause}", desc="utf8 error", pos=cause.valid_up_to(), cause=cause));
+ assert_eq!(format!("{:?}", err), format!("FromUtf8Error({:?}, {:?})", cause, invalid_utf8));
+ assert_eq!(format!("{:?}", err.cause().unwrap()), format!("{:?}", cause));
+ }
+
+ #[test]
+ fn tuple_wrapper_from() {
+ let cause = "one and a half times pi".parse::<f32>().unwrap_err();
+ let err = TupleWrapper::ParseFloatError(cause.clone());
+ let err_from: TupleWrapper = From::from(cause);
+ assert_eq!(err_from, err);
+ }
+
+ #[test]
+ fn tuple_wrapper_custom_from() {
+ let invalid_utf8: Vec<u8> = vec![0, 159, 146, 150];
+ let cause = String::from_utf8(invalid_utf8.clone()).unwrap_err();
+ let err = TupleWrapper::FromUtf8Error(cause.utf8_error().clone(), invalid_utf8);
+ let err_from: TupleWrapper = From::from(cause);
+ assert_eq!(err_from, err);
+ }
+
+ #[test]
+ fn tuple_wrapper_discard() {
+ let err: TupleWrapper = From::from("hello");
+ assert_eq!(format!("{}", err), format!("Discard"));
+ assert_eq!(format!("{:?}", err), format!("Discard"));
+ assert!(err.cause().is_none());
+ }
+
+ #[test]
+ fn tuple_wrapper_singleton() {
+ let err: TupleWrapper = TupleWrapper::Singleton;
+ assert_eq!(format!("{}", err), format!("Just a string"));
+ assert_eq!(format!("{:?}", err), format!("Singleton"));
+ assert!(err.cause().is_none());
+ }
+
+ quick_error! {
+ #[derive(Debug, PartialEq)]
+ pub enum StructWrapper {
+ // Utf8 Error
+ Utf8Error{ err: Utf8Error, hint: Option<&'static str> } {
+ cause(err)
+ display(me) -> ("{desc} at index {pos}: {err}", desc="utf8 error", pos=err.valid_up_to(), err=err)
+ from(err: Utf8Error) -> { err: err, hint: None }
+ }
+ // Utf8 Error
+ ExcessComma { descr: &'static str, } {
+ display("Error: {}", descr)
+ }
+ }
+ }
+
+ #[test]
+ fn struct_wrapper_err() {
+ let invalid_utf8: Vec<u8> = vec![0, 159, 146, 150];
+ let cause = String::from_utf8(invalid_utf8.clone()).unwrap_err().utf8_error();
+ let err: &Error = &StructWrapper::Utf8Error{ err: cause.clone(), hint: Some("nonsense") };
+ assert_eq!(format!("{}", err), format!("{desc} at index {pos}: {cause}", desc="utf8 error", pos=cause.valid_up_to(), cause=cause));
+ assert_eq!(format!("{:?}", err), format!("Utf8Error {{ err: {:?}, hint: {:?} }}", cause, Some("nonsense")));
+ assert_eq!(format!("{:?}", err.cause().unwrap()), format!("{:?}", cause));
+ }
+
+ #[test]
+ fn struct_wrapper_struct_from() {
+ let invalid_utf8: Vec<u8> = vec![0, 159, 146, 150];
+ let cause = String::from_utf8(invalid_utf8.clone()).unwrap_err().utf8_error();
+ let err = StructWrapper::Utf8Error{ err: cause.clone(), hint: None };
+ let err_from: StructWrapper = From::from(cause);
+ assert_eq!(err_from, err);
+ }
+
+ #[test]
+ fn struct_wrapper_excess_comma() {
+ let descr = "hello";
+ let err = StructWrapper::ExcessComma { descr: descr };
+ assert_eq!(format!("{}", err), format!("Error: {}", descr));
+ assert_eq!(format!("{:?}", err), format!("ExcessComma {{ descr: {:?} }}", descr));
+ assert!(err.cause().is_none());
+ }
+
+ quick_error! {
+ #[derive(Debug)]
+ pub enum ContextErr {
+ Float(src: String, err: ParseFloatError) {
+ context(s: &'a str, e: ParseFloatError) -> (s.to_string(), e)
+ display("Float error {:?}: {}", src, err)
+ }
+ Int { src: String, err: ParseIntError } {
+ context(s: &'a str, e: ParseIntError)
+ -> {src: s.to_string(), err: e}
+ display("Int error {:?}: {}", src, err)
+ }
+ Utf8(path: PathBuf, err: Utf8Error) {
+ context(p: AsRef<Path>, e: Utf8Error)
+ -> (p.as_ref().to_path_buf(), e)
+ display("Path error at {:?}: {}", path, err)
+ }
+ Utf8Str(s: String, err: ::std::io::Error) {
+ context(s: AsRef<str>, e: ::std::io::Error)
+ -> (s.as_ref().to_string(), e)
+ display("Str error {:?}: {}", s, err)
+ }
+ }
+ }
+
+ #[test]
+ fn parse_float_error() {
+ fn parse_float(s: &str) -> Result<f32, ContextErr> {
+ Ok(try!(s.parse().context(s)))
+ }
+ assert_eq!(format!("{}", parse_float("12ab").unwrap_err()),
+ r#"Float error "12ab": invalid float literal"#);
+ }
+
+ #[test]
+ fn parse_int_error() {
+ fn parse_int(s: &str) -> Result<i32, ContextErr> {
+ Ok(try!(s.parse().context(s)))
+ }
+ assert_eq!(format!("{}", parse_int("12.5").unwrap_err()),
+ r#"Int error "12.5": invalid digit found in string"#);
+ }
+
+ #[test]
+ fn debug_context() {
+ fn parse_int(s: &str) -> i32 {
+ s.parse().context(s).unwrap()
+ }
+ assert_eq!(parse_int("12"), 12);
+ assert_eq!(format!("{:?}", "x".parse::<i32>().context("x")),
+ r#"Err(Context("x", ParseIntError { kind: InvalidDigit }))"#);
+ }
+
+ #[test]
+ fn path_context() {
+ fn parse_utf<P: AsRef<Path>>(s: &[u8], p: P)
+ -> Result<(), ContextErr>
+ {
+ try!(::std::str::from_utf8(s).context(p));
+ Ok(())
+ }
+ let etext = parse_utf(b"a\x80\x80", "/etc").unwrap_err().to_string();
+ assert!(etext.starts_with(
+ "Path error at \"/etc\": invalid utf-8"));
+ let etext = parse_utf(b"\x80\x80", PathBuf::from("/tmp")).unwrap_err()
+ .to_string();
+ assert!(etext.starts_with(
+ "Path error at \"/tmp\": invalid utf-8"));
+ }
+
+ #[test]
+ fn conditional_compilation() {
+ quick_error! {
+ #[allow(dead_code)]
+ #[derive(Debug)]
+ pub enum Test {
+ #[cfg(feature = "foo")]
+ Variant
+ }
+ }
+ }
+}