1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142

//! `tor-basic-utils`: Utilities (low-level) for Tor
//!
//! Miscellaneous utilities for `tor-*` and `arti-*`.
//!
//! This crate lives at the *bottom* of the Tor crate stack.
//! So it contains only utilities which have no `tor-*` (or `arti-*`) dependencies.
//!
//! There is no particular theme.
//! More substantial sets of functionality with particular themes
//! are to be found in other `tor-*` crates.

#![deny(missing_docs)]
#![warn(noop_method_call)]
#![deny(unreachable_pub)]
#![warn(clippy::all)]
#![deny(clippy::await_holding_lock)]
#![deny(clippy::cargo_common_metadata)]
#![deny(clippy::cast_lossless)]
#![deny(clippy::checked_conversions)]
#![warn(clippy::cognitive_complexity)]
#![deny(clippy::debug_assert_with_mut_call)]
#![deny(clippy::exhaustive_enums)]
#![deny(clippy::exhaustive_structs)]
#![deny(clippy::expl_impl_clone_on_copy)]
#![deny(clippy::fallible_impl_from)]
#![deny(clippy::implicit_clone)]
#![deny(clippy::large_stack_arrays)]
#![warn(clippy::manual_ok_or)]
#![deny(clippy::missing_docs_in_private_items)]
#![deny(clippy::missing_panics_doc)]
#![warn(clippy::needless_borrow)]
#![warn(clippy::needless_pass_by_value)]
#![warn(clippy::option_option)]
#![warn(clippy::rc_buffer)]
#![deny(clippy::ref_option_ref)]
#![warn(clippy::semicolon_if_nothing_returned)]
#![warn(clippy::trait_duplication_in_bounds)]
#![deny(clippy::unnecessary_wraps)]
#![warn(clippy::unseparated_literal_suffix)]
#![deny(clippy::unwrap_used)]

use std::fmt;

pub mod retry;

// ----------------------------------------------------------------------

/// Function with the signature of `Debug::fmt` that just prints `".."`
///
/// ```
/// use educe::Educe;
/// use tor_basic_utils::skip_fmt;
///
/// #[derive(Educe, Default)]
/// #[educe(Debug)]
/// struct Wombat {
///     visible: usize,
///
///     #[educe(Debug(method = "skip_fmt"))]
///     invisible: [u8; 2],
/// }
///
/// assert_eq!( format!("{:?}", &Wombat::default()),
///             "Wombat { visible: 0, invisible: .. }" );
/// ```
pub fn skip_fmt<T>(_: &T, f: &mut fmt::Formatter) -> fmt::Result {
    /// Inner function avoids code bloat due to generics
    fn inner(f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "..")
    }
    inner(f)
}

// ----------------------------------------------------------------------

/// Define an "accessor trait", which describes structs that have fields of certain types
///
/// This can be useful if a large struct, living high up in the dependency graph,
/// contains fields that lower-lever crates want to be able to use without having
/// to copy the data about etc.
///
/// ```
/// // imagine this in the lower-level module
/// use tor_basic_utils::define_accessor_trait;
/// define_accessor_trait! {
///     pub trait View {
///         lorem: String,
///         ipsum: usize,
///    }
/// }
///
/// fn test_view<V: View>(v: &V) {
///     assert_eq!(v.lorem(), "sit");
///     assert_eq!(v.ipsum(), &42);
/// }
///
/// // imagine this in the higher-level module
/// use derive_more::AsRef;
/// #[derive(AsRef)]
/// struct Everything {
///     #[as_ref] lorem: String,
///     #[as_ref] ipsum: usize,
///     dolor: Vec<()>,
/// }
/// impl View for Everything { }
///
/// let everything = Everything {
///     lorem: "sit".into(),
///     ipsum: 42,
///     dolor: vec![()],
/// };
///
/// test_view(&everything);
/// ```
///
/// ### Generated code
///
/// ```
/// pub trait View: AsRef<String> + AsRef<usize> {
///     fn lorem(&self) -> &String { self.as_ref() }
///     fn ipsum(&self) -> &usize { self.as_ref() }
/// }
/// ```
#[macro_export]
macro_rules! define_accessor_trait {
    {
        $( #[ $attr:meta ])*
        $vis:vis trait $Trait:ident {
            $( $accessor:ident: $type:ty, )*
        }
    } => {
        $( #[ $attr ])*
        $vis trait $Trait: $( core::convert::AsRef<$type> + )* {
            $(
                /// Access the field
                fn $accessor(&self) -> &$type { core::convert::AsRef::as_ref(self) }
            )*
        }
    }
}

// ----------------------------------------------------------------------