uefi-macros: Drop the cstr16 macro

This is replaced by a new `cstr16` declarative macro in the `uefi` crate.

Author: nicholasbishop

uefi-macros/CHANGELOG.md

@@ -1,5 +1,9 @@
 # uefi-macros - [Unreleased]
 
+## Removed
+- Removed the `cstr16` macro. Use the `cstr16` declarative macro exported by the
+  `uefi` crate instead.
+
 # uefi-macros - 0.13.0 (2023-11-12)
 
 ## Changed

uefi-macros/src/lib.rs

@@ -288,47 +288,3 @@ pub fn cstr8(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
             .into(),
     }
 }
-
-/// Builds a `CStr16` literal at compile time from a string literal.
-///
-/// This will throw a compile error if an invalid character is in the passed string.
-///
-/// # Example
-/// ```rust
-/// # use uefi_macros::cstr16;
-/// // Empty string
-/// assert_eq!(cstr16!().to_u16_slice_with_nul(), [0]);
-/// assert_eq!(cstr16!("").to_u16_slice_with_nul(), [0]);
-/// // Non-empty string
-/// assert_eq!(cstr16!("test €").to_u16_slice_with_nul(), [116, 101, 115, 116, 32, 8364, 0]);
-/// ```
-#[proc_macro]
-pub fn cstr16(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
-    // Accept empty input.
-    if input.is_empty() {
-        return quote!(unsafe { ::uefi::CStr16::from_u16_with_nul_unchecked(&[0]) }).into();
-    }
-    let input: LitStr = parse_macro_input!(input);
-    let input = input.value();
-    // Accept "" input.
-    if input.is_empty() {
-        return quote!(unsafe { ::uefi::CStr16::from_u16_with_nul_unchecked(&[0]) }).into();
-    }
-
-    // Accept any non-empty string input.
-    match input
-        .chars()
-        .map(|c| u16::try_from(c as u32))
-        .collect::<Result<Vec<u16>, _>>()
-    {
-        Ok(c) => {
-            quote!(unsafe { ::uefi::CStr16::from_u16_with_nul_unchecked(&[ #(#c),* , 0 ]) }).into()
-        }
-        Err(_) => syn::Error::new_spanned(
-            input,
-            "There are UTF-8 characters that can't be transformed to UCS-2 character",
-        )
-        .into_compile_error()
-        .into(),
-    }
-}