motor: Use UTF-8 guarantee for OS strings

Author: thaliaarchi

library/std/src/os/motor/ffi.rs

@@ -3,35 +3,40 @@
 
 usecrate::ffi::{OsStr,OsString};
 usecrate::sealed::Sealed;
+usecrate::sys_common::{AsInner,IntoInner};
 
-/// Motor OS-specific extensions to [`OsString`].
+/// Motor OS–specific extensions to [`OsString`].
 ///
 /// This trait is sealed: it cannot be implemented outside the standard library.
 /// This is so that future additional methods are not breaking changes.
 pubtraitOsStringExt:Sealed{
-/// Motor OS strings are utf-8, and thus just strings.
-fnas_str(&self) -> &str;
+/// Yields the underlying UTF-8 string of this [`OsString`].
+///
+/// OS strings on Motor OS are guaranteed to be UTF-8, so are just strings.
+fninto_string(self) -> String;
 }
 
 implOsStringExtforOsString{
 #[inline]
-fnas_str(&self) -> &str{
-self.to_str().unwrap()
+fninto_string(self) -> String{
+self.into_inner().inner
 }
 }
 
-/// Motor OS-specific extensions to [`OsString`].
+/// Motor OS–specific extensions to [`OsString`].
 ///
 /// This trait is sealed: it cannot be implemented outside the standard library.
 /// This is so that future additional methods are not breaking changes.
 pubtraitOsStrExt:Sealed{
-/// Motor OS strings are utf-8, and thus just strings.
+/// Gets the underlying UTF-8 string view of the [`OsStr`] slice.
+///
+/// OS strings on Motor OS are guaranteed to be UTF-8, so are just strings.
 fnas_str(&self) -> &str;
 }
 
 implOsStrExtforOsStr{
 #[inline]
 fnas_str(&self) -> &str{
-self.to_str().unwrap()
+&self.as_inner().inner
 }
 }