fix: unwrap non-null assertion (x!) / satisfies in placeholders (parity with babel macro) (#247)

Author: pkasarda

crates/lingui_macro/src/macro_utils.rs

@@ -9,7 +9,7 @@ use swc_core::ecma::{ast::*, atoms::Atom};
 use swc_core::plugin::errors::HANDLER;
 
 fn expression_to_name(expr: &Expr, ctx: &mut MacroCtx) -> String {
-    let expr = unwrap_ts_as_expr(expr);
+    let expr = unwrap_ts_only_expr(expr);
 
     match expr {
         Expr::Ident(ident) => ident.sym.to_string(),
@@ -33,7 +33,7 @@ fn expression_to_name(expr: &Expr, ctx: &mut MacroCtx) -> String {
 }
 
 fn expression_to_value(expr: Box<Expr>) -> Box<Expr> {
-    let unwrapped = unwrap_ts_as_expr(&expr);
+    let unwrapped = unwrap_ts_only_expr(&expr);
 
     match unwrapped {
         Expr::Object(object) => {
@@ -66,14 +66,18 @@ fn expression_to_value(expr: Box<Expr>) -> Box<Expr> {
     }
 }
 
-// recursively expands TypeScript's as expressions until it reaches a real value
-fn unwrap_ts_as_expr(expr: &Expr) -> &Expr {
+// recursively unwraps TypeScript-only expression wrappers (`x as T`, `x!`,
+// `x satisfies T`) until it reaches a real value, so the inner expression drives
+// placeholder naming (e.g. `${x!}` → `{x}`, not `{0}`).
+fn unwrap_ts_only_expr(expr: &Expr) -> &Expr {
     let mut current = expr;
-    while let Expr::TsAs(TsAsExpr {
-        expr: inner_expr, ..
-    }) = current
-    {
-        current = inner_expr;
+    loop {
+        current = match current {
+            Expr::TsAs(TsAsExpr { expr, .. })
+            | Expr::TsNonNull(TsNonNullExpr { expr, .. })
+            | Expr::TsSatisfies(TsSatisfiesExpr { expr, .. }) => expr,
+            _ => break,
+        };
     }
     current
 }

crates/lingui_macro/tests/js_t.rs

@@ -228,3 +228,21 @@ to!(
      t`Hello World`
      "#
 );
+
+// TS-only expression wrappers unwrap to a named placeholder (parity with `as`),
+// matching @lingui/babel-plugin-lingui-macro (see lingui/js-lingui#2622).
+to!(
+    js_non_null_assertion_gets_named_placeholder,
+    r#"
+     import { t } from '@lingui/core/macro';
+     t`Variable ${name!}`;
+     "#
+);
+
+to!(
+    js_satisfies_gets_named_placeholder,
+    r#"
+     import { t } from '@lingui/core/macro';
+     t`Variable ${name satisfies string}`;
+     "#
+);

crates/lingui_macro/tests/snapshots/js_t__js_non_null_assertion_gets_named_placeholder.snap

@@ -0,0 +1,16 @@
+---
+source: crates/lingui_macro/tests/js_t.rs
+---
+import { t } from '@lingui/core/macro';
+t`Variable ${name!}`;
+
+↓ ↓ ↓ ↓ ↓ ↓
+
+import { i18n as $_i18n } from "@lingui/core";
+$_i18n._(/*i18n*/ {
+    id: "xRRkAE",
+    message: "Variable {name}",
+    values: {
+        name: name!
+    }
+});

crates/lingui_macro/tests/snapshots/js_t__js_satisfies_gets_named_placeholder.snap

@@ -0,0 +1,16 @@
+---
+source: crates/lingui_macro/tests/js_t.rs
+---
+import { t } from '@lingui/core/macro';
+t`Variable ${name satisfies string}`;
+
+↓ ↓ ↓ ↓ ↓ ↓
+
+import { i18n as $_i18n } from "@lingui/core";
+$_i18n._(/*i18n*/ {
+    id: "xRRkAE",
+    message: "Variable {name}",
+    values: {
+        name: name satisfies string
+    }
+});