proc-macro-api: Fix warnings about clippy str_to_string rule

crates/proc-macro-api/src/lib.rs

@@ -197,7 +197,7 @@ pub fn expand(
                     &deserialize_span_data_index_map(&resp.span_data_table),
                 )
             })),
-            _ => Err(ServerError { message: "unexpected response".to_string(), io: None }),
+            _ => Err(ServerError { message: "unexpected response".to_owned(), io: None }),
         }
     }
 }

crates/proc-macro-api/src/msg/flat.rs

@@ -419,7 +419,7 @@ pub(crate) fn intern(&mut self, text: &'a str) -> u32 {
         let table = &mut self.text;
         *self.string_table.entry(text).or_insert_with(|| {
             let idx = table.len();
-            table.push(text.to_string());
+            table.push(text.to_owned());
             idx as u32
         })
     }

crates/proc-macro-api/src/process.rs

@@ -78,7 +78,7 @@ pub(crate) fn version_check(&mut self) -> Result<u32, ServerError> {
 
         match response {
             Response::ApiVersionCheck(version) => Ok(version),
-            _ => Err(ServerError { message: "unexpected response".to_string(), io: None }),
+            _ => Err(ServerError { message: "unexpected response".to_owned(), io: None }),
         }
     }
 
@@ -90,7 +90,7 @@ fn enable_rust_analyzer_spans(&mut self) -> Result<SpanMode, ServerError> {
 
         match response {
             Response::SetConfig(crate::msg::ServerConfig { span_mode }) => Ok(span_mode),
-            _ => Err(ServerError { message: "unexpected response".to_string(), io: None }),
+            _ => Err(ServerError { message: "unexpected response".to_owned(), io: None }),
         }
     }
 
@@ -104,7 +104,7 @@ pub(crate) fn find_proc_macros(
 
         match response {
             Response::ListMacros(it) => Ok(it),
-            _ => Err(ServerError { message: "unexpected response".to_string(), io: None }),
+            _ => Err(ServerError { message: "unexpected response".to_owned(), io: None }),
         }
     }
 

crates/proc-macro-api/src/version.rs

@@ -38,7 +38,7 @@ macro_rules! err {
     let version_part = items.next().ok_or_else(|| err!("no version string"))?;
     let mut version_parts = version_part.split('-');
     let version = version_parts.next().ok_or_else(|| err!("no version"))?;
-    let channel = version_parts.next().unwrap_or_default().to_string();
+    let channel = version_parts.next().unwrap_or_default().to_owned();
 
     let commit = match items.next() {
         Some(commit) => {