chore: replace atty with is-terminal

Cargo.toml

@@ -37,14 +37,14 @@ pre-release-replacements = [
 ]
 
 [features]
-default = ["termcolor", "atty", "humantime", "regex"]
+default = ["termcolor", "is-terminal", "humantime", "regex"]
 
 [dependencies]
 log = { version = "0.4.8", features = ["std"] }
 regex = { version = "1.0.3", optional = true, default-features=false, features=["std", "perf"] }
 termcolor = { version = "1.1.1", optional = true }
 humantime = { version = "2.0.0", optional = true }
-atty = { version = "0.2.5", optional = true }
+is-terminal = { version = "0.4.0", optional = true }
 
 [[test]]
 name = "regexp_filter"

ci/src/main.rs

@@ -2,7 +2,7 @@ mod permute;
 mod task;
 
 fn main() {
-    let features = ["termcolor", "humantime", "atty", "regex"];
+    let features = ["termcolor", "humantime", "is-terminal", "regex"];
 
     // Run a default build
     if !task::test(Default::default()) {

src/fmt/writer/atty.rs

@@ -1,24 +1,28 @@
 /*
 This internal module contains the terminal detection implementation.
 
-If the `atty` crate is available then we use it to detect whether we're
-attached to a particular TTY. If the `atty` crate is not available we
-assume we're not attached to anything. This effectively prevents styles
-from being printed.
+If the `is-terminal` crate is available then we use it to detect whether
+we're attached to a particular TTY. If the `is-terminal` crate is not
+available we assume we're not attached to anything. This effectively
+prevents styles from being printed.
 */
 
-#[cfg(feature = "atty")]
+#[cfg(feature = "is-terminal")]
 mod imp {
+    use std::io::{stderr, stdout};
+
+    use is_terminal::IsTerminal;
+
     pub(in crate::fmt) fn is_stdout() -> bool {
-        atty::is(atty::Stream::Stdout)
+        stdout().is_terminal()
     }
 
     pub(in crate::fmt) fn is_stderr() -> bool {
-        atty::is(atty::Stream::Stderr)
+        stderr().is_terminal()
     }
 }
 
-#[cfg(not(feature = "atty"))]
+#[cfg(not(feature = "is-terminal"))]
 mod imp {
     pub(in crate::fmt) fn is_stdout() -> bool {
         false