feat: set useDefineForClassFields to true (#10119)

Fixes: #9773 

4 files changed, 15 insertions, 3 deletions

diff --git a/cli/tests/091_use_define_for_class_fields.ts b/cli/tests/091_use_define_for_class_fields.ts
new file mode 100644
index 000000000..9be984abf
--- /dev/null
+++ b/cli/tests/091_use_define_for_class_fields.ts
@@ -0,0 +1,4 @@
+class A {
+  b = this.a;
+  constructor(public a: unknown) {}
+}
diff --git a/cli/tests/091_use_define_for_class_fields.ts.out b/cli/tests/091_use_define_for_class_fields.ts.out
new file mode 100644
index 000000000..08f94a967
--- /dev/null
+++ b/cli/tests/091_use_define_for_class_fields.ts.out
@@ -0,0 +1,4 @@
+[WILDCARD]error: TS2729 [ERROR]: Property 'a' is used before its initialization.
+  b = this.a;
+           ^
+[WILDCARD]
diff --git a/cli/tests/bundle/fixture13.out b/cli/tests/bundle/fixture13.out
index 2c5115280..1c7a8c991 100644
--- a/cli/tests/bundle/fixture13.out
+++ b/cli/tests/bundle/fixture13.out
@@ -9,11 +9,9 @@ function d() {
     return Object.assign(promise, methods);
 }
 class A {
+    s = d();
     a() {
         this.s.resolve();
     }
-    constructor(){
-        this.s = d();
-    }
 }
 new A();
diff --git a/cli/tests/integration_tests.rs b/cli/tests/integration_tests.rs
index 827fc871b..5067b8163 100644
--- a/cli/tests/integration_tests.rs
+++ b/cli/tests/integration_tests.rs
@@ -2867,6 +2867,12 @@ console.log("finish");
     util::test_pty(args, output, input);
   }
 
+  itest!(_091_use_define_for_class_fields {
+    args: "run 091_use_define_for_class_fields.ts",
+    output: "091_use_define_for_class_fields.ts.out",
+    exit_code: 1,
+  });
+
   itest!(js_import_detect {
     args: "run --quiet --reload js_import_detect.ts",
     output: "js_import_detect.ts.out",