fix(fmt): "singleQuote": true should prefer single quote—not always…

… use one (#21470)

cli/tools/fmt.rs

@@ -523,7 +523,7 @@ fn get_resolved_typescript_config(
  if let Some(single_quote) = options.single_quote {
  if single_quote {
  builder.quote_style(
- dprint_plugin_typescript::configuration::QuoteStyle::AlwaysSingle,
+ dprint_plugin_typescript::configuration::QuoteStyle::PreferSingle,
  );
  }
  }
@@ -792,4 +792,23 @@ mod test {
 
  assert_eq!(result, Some("11".to_string()));
  }
+
+ #[test]
+ fn test_single_quote_true_prefers_single_quote() {
+ let file_text = format_file(
+ &PathBuf::from("test.ts"),
+ "console.log(\"there's\");\nconsole.log('hi');\nconsole.log(\"bye\")\n",
+ &FmtOptionsConfig {
+ single_quote: Some(true),
+ ..Default::default()
+ },
+ )
+ .unwrap()
+ .unwrap();
+ assert_eq!(
+ file_text,
+ // should use double quotes for the string with a single quote
+ "console.log(\"there's\");\nconsole.log('hi');\nconsole.log('bye');\n",
+ );
+ }
 }