string escape edgecase (#3717)bun-v0.7.0

* fix edgecase when joining rope strings with backtick

* bonus bugfix in ts decorator

* Update transpiler.test.js

* Fix test

---------

Co-authored-by: Jarred Sumner <709451+Jarred-Sumner@users.noreply.github.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>

4 files changed, 22 insertions, 8 deletions

diff --git a/src/js_parser.zig b/src/js_parser.zig
index f5dda75f0..6390dfdba 100644
--- a/src/js_parser.zig
+++ b/src/js_parser.zig
@@ -213,6 +213,8 @@ fn foldStringAddition(lhs: Expr, rhs: Expr) ?Expr {
                     rhs_clone.data.e_string,
                 );
 
+                orig.prefer_template = orig.prefer_template or rhs_clone.data.e_string.prefer_template;
+
                 return Expr.init(E.String, orig, lhs.loc);
             }
         },
@@ -19517,7 +19519,8 @@ fn NewParser_(
                                 .e_number => |k| p.newExpr(E.Number{ .value = k.value }, loc),
                                 .e_string => |k| p.newExpr(E.String{ .data = k.data }, loc),
                                 .e_index => |k| p.newExpr(E.Index{ .target = k.target, .index = k.index }, loc),
-                                else => unreachable,
+                                .e_private_identifier => |k| p.newExpr(E.PrivateIdentifier{ .ref = k.ref }, loc),
+                                else => bun.unreachablePanic("Unexpected AST node type {any}", .{prop.key.?}),
                             };
 
                             const descriptor_kind: f64 = if (!prop.flags.contains(.is_method)) 2 else 1;
diff --git a/src/js_printer.zig b/src/js_printer.zig
index 08a1cb5c1..1f920327c 100644
--- a/src/js_printer.zig
+++ b/src/js_printer.zig
@@ -2592,7 +2592,7 @@ fn NewPrinter(
                     p.addSourceMapping(expr.loc);
 
                     // If this was originally a template literal, print it as one as long as we're not minifying
-                    if (e.prefer_template) {
+                    if (e.prefer_template and !p.options.minify_syntax) {
                         p.print("`");
                         p.printStringContent(e, '`');
                         p.print("`");
@@ -3065,6 +3065,17 @@ fn NewPrinter(
             while (i < len) {
                 switch (utf8[i]) {
                     '\\' => i += 2,
+                    '$' => {
+                        if (comptime c == '`') {
+                            p.print(utf8[0..i]);
+                            p.print("\\$");
+                            utf8 = utf8[i + 1 ..];
+                            len = utf8.len;
+                            i = 0;
+                        } else {
+                            i += 1;
+                        }
+                    },
                     c => {
                         p.print(utf8[0..i]);
                         p.print("\\" ++ &[_]u8{c});
diff --git a/test/bundler/bundler_string.test.ts b/test/bundler/bundler_string.test.ts
index 3c2d7802c..45faaee3e 100644
--- a/test/bundler/bundler_string.test.ts
+++ b/test/bundler/bundler_string.test.ts
@@ -14,8 +14,8 @@ const templateStringTests: Record<string, TemplateStringTest> = {
   // note for writing tests: .print is .trim()'ed due to how run.stdout works
   Empty: { expr: '""', captureRaw: '""' },
   NullByte: { expr: '"hello\0"', captureRaw: '"hello\0"' },
-  EmptyTemplate: { expr: "``", captureRaw: "``" },
-  ConstantTemplate: { expr: "`asdf`", captureRaw: "`asdf`" },
+  EmptyTemplate: { expr: "``", captureRaw: '""' },
+  ConstantTemplate: { expr: "`asdf`", captureRaw: '"asdf"' },
   AddConstant: { expr: "`${7 + 6}`", capture: true },
   AddConstant2: { expr: "`${7 + 6 + 96}`", capture: true },
   AddConstant3: { expr: "`${0.1 + 0.2}`", print: true },
@@ -80,8 +80,8 @@ const templateStringTests: Record<string, TemplateStringTest> = {
   FoldNested4: { expr: "`a${`b`}c${`${`${`${'d'}`}`}`}e`", capture: true },
   FoldNested5: { expr: "`\\$${`d`}`", print: true }, // could be captured
   FoldNested6: { expr: "`a\0${5}c\\${{$${`d`}e`", print: true },
-  EscapedDollar: { expr: "`\\${'a'}`", captureRaw: "`\\${'a'}`" },
-  EscapedDollar2: { expr: "`\\${'a'}\\${'b'}`", captureRaw: "`\\${'a'}\\${'b'}`" },
+  EscapedDollar: { expr: "`\\${'a'}`", captureRaw: "\"${'a'}\"" },
+  EscapedDollar2: { expr: "`\\${'a'}\\${'b'}`", captureRaw: "\"${'a'}${'b'}\"" },
 };
 
 describe("bundler", () => {
diff --git a/test/transpiler/transpiler.test.js b/test/transpiler/transpiler.test.js
index f83c00296..8c77dffe6 100644
--- a/test/transpiler/transpiler.test.js
+++ b/test/transpiler/transpiler.test.js
@@ -2809,7 +2809,7 @@ console.log(foo, array);
 
       expectPrinted("'string' + `template`", `"stringtemplate"`);
 
-      expectPrinted("`template` + 'string'", "`templatestring`");
+      expectPrinted("`template` + 'string'", '"templatestring"');
 
       // TODO: string template simplification
       // expectPrinted("'string' + `a${foo}b`", "`stringa${foo}b`");
@@ -3088,7 +3088,7 @@ console.log(foo, array);
       expectPrinted_('const x = `str` + "``";', "const x = `str\\`\\``");
       expectPrinted_('const x = `` + "`";', "const x = `\\``");
       expectPrinted_('const x = `` + "``";', "const x = `\\`\\``");
-      expectPrinted_('const x = "``" + ``;', 'const x = "``"');
+      expectPrinted_('const x = "``" + ``;', "const x = `\\`\\``");
     });
   });