fix bug with no-identifier var in dead branches

evanw · Feb 23, 2024 · a064abc · a064abc
1 parent 40711af
commit a064abc
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Showing 2 changed files with 5 additions and 0 deletions.
diff --git a/internal/js_parser/js_parser.go b/internal/js_parser/js_parser.go
@@ -8355,6 +8355,9 @@ func shouldKeepStmtInDeadControlFlow(stmt js_ast.Stmt) bool {
 		for _, decl := range s.Decls {
 			identifiers = findIdentifiers(decl.Binding, identifiers)
 		}
+		if len(identifiers) == 0 {
+			return false
+		}
 		s.Decls = identifiers
 		return true
 

diff --git a/internal/js_parser/js_parser_test.go b/internal/js_parser/js_parser_test.go
@@ -5241,6 +5241,8 @@ func TestTrimCodeInDeadControlFlow(t *testing.T) {
 	expectPrintedMangle(t, "if (1) a(); else { var a = b }", "if (1)\n  a();\nelse\n  var a;\n")
 	expectPrintedMangle(t, "if (1) a(); else { var [a] = b }", "if (1)\n  a();\nelse\n  var a;\n")
 	expectPrintedMangle(t, "if (1) a(); else { var {x: a} = b }", "if (1)\n  a();\nelse\n  var a;\n")
+	expectPrintedMangle(t, "if (1) a(); else { var [] = b }", "a();\n")
+	expectPrintedMangle(t, "if (1) a(); else { var {} = b }", "a();\n")
 	expectPrintedMangle(t, "if (1) a(); else { function a() {} }", "if (1)\n  a();\nelse\n  var a;\n")
 	expectPrintedMangle(t, "if (1) a(); else { for(;;){var a} }", "if (1)\n  a();\nelse\n  for (; ; )\n    var a;\n")
 	expectPrintedMangle(t, "if (1) { a(); b() } else { var a; var b; }", "if (1)\n  a(), b();\nelse\n  var a, b;\n")