Backport is_ok_and

On Rust versions that have it, this will be unused, so ignore the unused
import warning.

fish-rust/src/editable_line.rs

@@ -2,6 +2,7 @@ use std::pin::Pin;
 
 use cxx::{CxxWString, UniquePtr};
 
+#[allow(unused_imports)]
 use crate::future::IsSomeAnd;
 use crate::highlight::{HighlightSpec, HighlightSpecListFFI};
 use crate::wchar::prelude::*;

fish-rust/src/fish_indent.rs

@@ -21,8 +21,8 @@ use crate::env::environment::Environment;
 use crate::env::EnvStack;
 use crate::expand::INTERNAL_SEPARATOR;
 use crate::fds::set_cloexec;
-use crate::future::IsSomeAnd;
-use crate::future::IsSorted;
+#[allow(unused_imports)]
+use crate::future::{IsOkAnd, IsSomeAnd, IsSorted};
 use crate::global_safety::RelaxedAtomicBool;
 use crate::highlight::{colorize, highlight_shell, HighlightRole, HighlightSpec};
 use crate::operation_context::OperationContext;

fish-rust/src/future.rs

@@ -24,6 +24,24 @@ impl<T> IsSomeAnd for Option<T> {
     }
 }
 
+pub trait IsOkAnd {
+    type Type;
+    type Error;
+    #[allow(clippy::wrong_self_convention)]
+    fn is_ok_and(self, s: impl FnOnce(Self::Type) -> bool) -> bool;
+}
+
+impl<T, E> IsOkAnd for Result<T, E> {
+    type Type = T;
+    type Error = E;
+    fn is_ok_and(self, f: impl FnOnce(T) -> bool) -> bool {
+        match self {
+            Ok(v) => f(v),
+            Err(_) => false,
+        }
+    }
+}
+
 pub trait IsSorted {
     type T;
     fn is_sorted_by(&self, pred: impl Fn(&Self::T, &Self::T) -> Option<std::cmp::Ordering>)

fish-rust/src/pager.rs

@@ -11,6 +11,7 @@ use crate::compat::MB_CUR_MAX;
 use crate::complete::{Completion, CompletionListFfi};
 use crate::editable_line::EditableLine;
 use crate::fallback::{fish_wcswidth, fish_wcwidth};
+#[allow(unused_imports)]
 use crate::future::IsSomeAnd;
 use crate::highlight::{highlight_shell, HighlightRole, HighlightSpec};
 use crate::operation_context::OperationContext;

fish-rust/src/screen.rs

@@ -27,6 +27,7 @@ use crate::curses::{term, tparm0, tparm1};
 use crate::env::{EnvStackRef, Environment, TERM_HAS_XN};
 use crate::fallback::fish_wcwidth;
 use crate::flog::FLOGF;
+#[allow(unused_imports)]
 use crate::future::IsSomeAnd;
 use crate::global_safety::RelaxedAtomicBool;
 use crate::highlight::{HighlightColorResolver, HighlightSpecListFFI};