Replace #[doc = ".."] with #[command(description = "...")]

crates/teloxide-macros/src/command_attr.rs

@@ -7,7 +7,8 @@ use crate::{
 };
 
 use proc_macro2::Span;
-use syn::Attribute;
+use quote::quote_spanned;
+use syn::{parse::Parser, spanned::Spanned, Attribute};
 
 /// All attributes that can be used for `derive(BotCommands)`
 pub(crate) struct CommandAttrs {
@@ -48,9 +49,40 @@ enum CommandAttrKind {
 impl CommandAttrs {
     pub fn from_attributes(attributes: &[Attribute]) -> Result<Self> {
         use CommandAttrKind::*;
+        // Convert the `doc` attribute into `command(description = "...")`
+        let attributes = attributes
+            .iter()
+            .map(|attr| {
+                if attr.path.is_ident("doc") {
+                    // Extract the token literal from the doc attribute.
+                    let description = attr
+                        .tokens
+                        .clone()
+                        .into_iter()
+                        .nth(1)
+                        .map(|t| {
+                            // remove first and last quotes only, is expected to be a string literal
+                            let mut s = t.to_string();
+                            s.remove(0);
+                            s.pop();
+                            s.trim().replace(r"\\n", "\n")
+                        })
+                        .unwrap_or_default();
+                    // Convert the doc attribute into a command description attribute.
+                    let sp = attr.span();
+                    let attr = Attribute::parse_outer
+                        .parse2(quote_spanned!(sp => #[command(description = #description)]))
+                        .unwrap();
+                    // SAFETY: `parse_outer` always returns a single attribute.
+                    attr.into_iter().next().unwrap()
+                } else {
+                    attr.clone()
+                }
+            })
+            .collect::<Vec<_>>();
 
         fold_attrs(
-            attributes,
+            attributes.iter(),
             is_command_attribute,
             CommandAttr::parse,
             Self {