is_terminal_polyfill/
lib.rs

1//! > Polyfill for `is_terminal` stdlib feature for use with older MSRVs
2
3#![cfg_attr(docsrs, feature(doc_auto_cfg))]
4#![warn(clippy::print_stderr)]
5#![warn(clippy::print_stdout)]
6
7/// Trait to determine if a descriptor/handle refers to a terminal/tty.
8pub trait IsTerminal: sealed::Sealed {
9    /// Returns `true` if the descriptor/handle refers to a terminal/tty.
10    ///
11    /// On platforms where Rust does not know how to detect a terminal yet, this will return
12    /// `false`. This will also return `false` if an unexpected error occurred, such as from
13    /// passing an invalid file descriptor.
14    ///
15    /// # Platform-specific behavior
16    ///
17    /// On Windows, in addition to detecting consoles, this currently uses some heuristics to
18    /// detect older msys/cygwin/mingw pseudo-terminals based on device name: devices with names
19    /// starting with `msys-` or `cygwin-` and ending in `-pty` will be considered terminals.
20    /// Note that this [may change in the future][changes].
21    ///
22    /// [changes]: std::io#platform-specific-behavior
23    fn is_terminal(&self) -> bool;
24}
25
26mod sealed {
27    pub trait Sealed {}
28}
29
30macro_rules! impl_is_terminal {
31    ($($t:ty),*$(,)?) => {$(
32        impl sealed::Sealed for $t {}
33
34        impl IsTerminal for $t {
35            #[inline]
36            fn is_terminal(&self) -> bool {
37                std::io::IsTerminal::is_terminal(self)
38            }
39        }
40    )*}
41}
42
43impl_is_terminal!(
44    std::fs::File,
45    std::io::Stdin,
46    std::io::StdinLock<'_>,
47    std::io::Stdout,
48    std::io::StdoutLock<'_>,
49    std::io::Stderr,
50    std::io::StderrLock<'_>
51);
is_terminal_polyfill/lib.rs

is_terminal_polyfill/
lib.rs
