fix: backslash in tagged template

src/ast_utils.rs

@@ -52,14 +52,22 @@ pub fn get_expr_as_string(val: &Box<Expr>) -> Option<String> {
     // `Hello`
     Expr::Tpl(Tpl {quasis, ..}) => {
       if quasis.len() == 1 {
-        return Some(quasis.get(0).unwrap().raw.to_string());
+        return Some(get_template_string_cooked_string(quasis.get(0).unwrap()));
       } else { None }
     }
 
     _ => None
   }
 }
 
+pub fn get_template_string_cooked_string(element: &TplElement) -> String {
+  if let Some(cooked) = &element.cooked {
+    cooked.to_string()
+  } else {
+    element.raw.to_string()
+  }
+}
+
 pub fn pick_jsx_attrs(mut attrs: Vec<JSXAttrOrSpread>, names: HashSet<&str>) -> Vec<JSXAttrOrSpread> {
     attrs.retain(|attr| {
         if let JSXAttrOrSpread::JSXAttr(attr) = attr {

src/macro_utils.rs

@@ -110,7 +110,7 @@ impl MacroCtx {
         let mut tokens: Vec<MsgToken> = Vec::with_capacity(tpl.quasis.len());
 
         for (i, tpl_element) in tpl.quasis.iter().enumerate() {
-            tokens.push(MsgToken::String(tpl_element.raw.to_string()));
+            tokens.push(MsgToken::String(get_template_string_cooked_string(tpl_element)));
 
             if let Some(exp) = tpl.exprs.get(i) {
                 if let Expr::Call(call) = exp.as_ref() {

src/tests/js_t.rs

@@ -162,6 +162,21 @@ to!(
      "#
 );
 
+to!(
+    js_backslash_newlines_are_preserved,
+    r#"
+       import { t } from '@lingui/macro';
+         t`Multiline\nstring`;
+    "#,
+     r#"
+        import { i18n } from "@lingui/core";
+        i18n._({
+            id: "EfogM+",
+            message: "Multiline\nstring"
+        });
+     "#
+);
+
 to!(
     js_support_message_descriptor_in_t_fn,
     r#"