Remove FormatFStringPart

crates/ruff_python_formatter/src/expression/expr_f_string.rs

@@ -4,7 +4,7 @@ use ruff_text_size::TextSlice;
 use crate::expression::parentheses::{
     in_parentheses_only_group, NeedsParentheses, OptionalParentheses,
 };
-use crate::other::f_string_part::FormatFStringPart;
+use crate::other::f_string::FormatFString;
 use crate::prelude::*;
 use crate::string::implicit::FormatImplicitConcatenatedStringFlat;
 use crate::string::{implicit::FormatImplicitConcatenatedString, Quoting, StringLikeExtensions};
@@ -17,8 +17,11 @@ impl FormatNodeRule<ExprFString> for FormatExprFString {
         let ExprFString { value, .. } = item;
 
         if let [f_string_part] = value.as_slice() {
-            FormatFStringPart::new(f_string_part, f_string_quoting(item, f.context().source()))
-                .fmt(f)
+            // SAFETY: A single string literal cannot be an f-string. This is guaranteed by the
+            // [`ruff_python_ast::FStringValue::single`] constructor.
+            let f_string = f_string_part.as_f_string().unwrap();
+
+            FormatFString::new(f_string, f_string_quoting(item, f.context().source())).fmt(f)
         } else {
             // Always join fstrings that aren't parenthesized and thus, are always on a single line.
             if !f.context().node_level().is_parenthesized() {

crates/ruff_python_formatter/src/other/mod.rs

@@ -8,7 +8,6 @@ pub(crate) mod elif_else_clause;
 pub(crate) mod except_handler_except_handler;
 pub(crate) mod f_string;
 pub(crate) mod f_string_element;
-pub(crate) mod f_string_part;
 pub(crate) mod identifier;
 pub(crate) mod keyword;
 pub(crate) mod match_case;