From 9cc1bb4397ff8e7f8dafffe16f0d9ef8323f5a99 Mon Sep 17 00:00:00 2001
From: RiskyMH <git@riskymh.dev>
Date: Wed, 6 Aug 2025 01:27:54 +1000
Subject: [PATCH] allow template literals in bun macros

---
 src/ast/Macro.zig                          | 51 +++++++++++++++++++++-
 test/bundler/transpiler/macro-test.test.ts | 24 ++++++++++
 test/bundler/transpiler/macro.ts           | 13 ++++++
 3 files changed, 86 insertions(+), 2 deletions(-)

diff --git a/src/ast/Macro.zig b/src/ast/Macro.zig
index b4b3f6dbd4..261ddb2152 100644
--- a/src/ast/Macro.zig
+++ b/src/ast/Macro.zig
@@ -579,8 +579,55 @@ pub const Runner = struct {
                     out.* = value;
                 }
             },
-            .e_template => {
-                @panic("TODO: support template literals in macros");
+            .e_template => |template| {
+                // For tagged template literals, the first argument is an array of template strings
+                // followed by the interpolated values as separate arguments
+                const parts_count = template.parts.len;
+                const total_args = 1 + parts_count + @as(usize, @intFromBool(javascript_object != .zero));
+                js_args = try allocator.alloc(jsc.JSValue, total_args);
+                js_processed_args_len = total_args;
+
+                var template_strings = try allocator.alloc(jsc.JSValue, parts_count + 1);
+                defer allocator.free(template_strings);
+
+                var head_str = switch (template.head) {
+                    .cooked => |str| str,
+                    .raw => |raw| E.String.init(raw),
+                };
+                template_strings[0] = try head_str.toJS(allocator, globalObject);
+                template_strings[0].protect();
+
+                for (template.parts, 1..) |part, i| {
+                    var tail_str = switch (part.tail) {
+                        .cooked => |str| str,
+                        .raw => |raw| E.String.init(raw),
+                    };
+                    template_strings[i] = try tail_str.toJS(allocator, globalObject);
+                    template_strings[i].protect();
+                }
+
+                js_args[0] = try jsc.JSArray.create(globalObject, template_strings);
+                js_args[0].protect();
+
+                for (template_strings) |str| {
+                    str.unprotect();
+                }
+
+                for (template.parts, 0..) |part, i| {
+                    const expr = part.value;
+                    const value = expr.toJS(
+                        allocator,
+                        globalObject,
+                    ) catch |e| {
+                        for (js_args[0 .. i + 1]) |arg| {
+                            arg.unprotect();
+                        }
+                        js_processed_args_len = i + 1;
+                        return e;
+                    };
+                    value.protect();
+                    js_args[i + 1] = value;
+                }
             },
             else => {
                 @panic("Unexpected caller type");
diff --git a/test/bundler/transpiler/macro-test.test.ts b/test/bundler/transpiler/macro-test.test.ts
index bc5ea871f3..e08981dceb 100644
--- a/test/bundler/transpiler/macro-test.test.ts
+++ b/test/bundler/transpiler/macro-test.test.ts
@@ -9,6 +9,9 @@ import defaultMacro, {
   identity as identity1,
   identity as identity2,
   ireturnapromise,
+  simpleTag,
+  interpolateTag,
+  objectTag,
 } from "./macro.ts" assert { type: "macro" };
 
 import * as macros from "./macro.ts" assert { type: "macro" };
@@ -118,6 +121,15 @@ test("namespace import", () => {
   expect(macros.escape()).toBe("\\\f\n\r\t\v\0'\"`$\x00\x0B\x0C");
 });
 
+test("varables", () => {
+  const a = "A";
+  expect(identity(a)).toBe("A");
+});
+
+test("template string basic", () => {
+  expect(identity(`A`)).toBe("A");
+});
+
 // test("template string ascii", () => {
 //   expect(identity(`A${""}`)).toBe("A");
 // });
@@ -129,3 +141,15 @@ test("namespace import", () => {
 test("ireturnapromise", async () => {
   expect(await ireturnapromise()).toEqual("aaa");
 });
+
+test("template literals with macros", () => {
+  expect(simpleTag`World`).toBe("Hello World!");
+  expect(interpolateTag`Alice${100}`).toBe("User Alice has 100 points");
+  expect(objectTag`${{ name: "Bob", age: 25 }}`).toBe("Name: Bob, Age: 25");
+});
+
+test("template literals with namespace import", () => {
+  expect(macros.simpleTag`Test`).toBe("Hello Test!");
+  expect(macros.interpolateTag`Jane${50}`).toBe("User Jane has 50 points");
+  expect(macros.objectTag`${{ name: "Alice", age: 30 }}`).toBe("Name: Alice, Age: 30");
+});
diff --git a/test/bundler/transpiler/macro.ts b/test/bundler/transpiler/macro.ts
index 9da8d72c5a..17db327147 100644
--- a/test/bundler/transpiler/macro.ts
+++ b/test/bundler/transpiler/macro.ts
@@ -23,3 +23,16 @@ export async function ireturnapromise() {
   setTimeout(() => resolve("aaa"), 100);
   return promise;
 }
+
+export function simpleTag(strings: TemplateStringsArray, ..._values: any[]) {
+  return `Hello ${strings[0]}!`;
+}
+
+export function interpolateTag(strings: TemplateStringsArray, ...values: any[]) {
+  return `User ${strings[0]} has ${values[0]} points`;
+}
+
+export function objectTag(_strings: TemplateStringsArray, ...values: any[]) {
+  const obj = values[0];
+  return `Name: ${obj.name}, Age: ${obj.age}`;
+}