fix: Handle strict field initialization in inlined ctors (#1369)

src/compiler.ts

@@ -7110,6 +7110,13 @@ export class Compiler extends DiagnosticEmitter {
     // Compile the called function's body in the scope of the inlined flow
     this.compileFunctionBody(instance, body);
 
+    // If a constructor, perform field init checks on its flow directly
+    if (instance.is(CommonFlags.CONSTRUCTOR)) {
+      let parent = instance.parent;
+      assert(parent.kind == ElementKind.CLASS);
+      this.checkFieldInitializationInFlow(<Class>parent, flow);
+    }
+
     // Free any new scoped locals and reset to the original flow
     if (!flow.is(FlowFlags.TERMINATES)) {
       this.performAutoreleases(flow, body);
@@ -9326,7 +9333,11 @@ export class Compiler extends DiagnosticEmitter {
     if (!classInstance) return module.unreachable();
     if (contextualType == Type.void) constraints |= Constraints.WILL_DROP;
     var ctor = this.ensureConstructor(classInstance, expression);
-    this.checkFieldInitialization(classInstance, expression);
+    if (!ctor.hasDecorator(DecoratorFlags.INLINE)) {
+      // Inlined ctors haven't been compiled yet and are checked upon inline
+      // compilation of their body instead.
+      this.checkFieldInitialization(classInstance, expression);
+    }
     return this.compileInstantiate(ctor, expression.args, constraints, expression);
   }
 
@@ -9453,10 +9464,14 @@ export class Compiler extends DiagnosticEmitter {
   checkFieldInitialization(classInstance: Class, relatedNode: Node | null = null): void {
     if (classInstance.didCheckFieldInitialization) return;
     classInstance.didCheckFieldInitialization = true;
+    var ctor = assert(classInstance.constructorInstance);
+    this.checkFieldInitializationInFlow(classInstance, ctor.flow, relatedNode);
+  }
+
+  /** Checks that all class fields have been initialized in the specified flow. */
+  checkFieldInitializationInFlow(classInstance: Class, flow: Flow, relatedNode: Node | null = null): void {
     var members = classInstance.members;
     if (members) {
-      let ctor = assert(classInstance.constructorInstance);
-      let flow = ctor.flow;
       for (let _values = Map_values(members), i = 0, k = _values.length; i < k; ++i) {
         let element = _values[i];
         if (element.kind == ElementKind.FIELD && element.parent == classInstance) {

tests/compiler/field-initialization-errors.json

@@ -5,6 +5,7 @@
   "stderr": [
     "TS2564: Property 'field-initialization-errors/Ref.a' has no initializer",
     "TS2564: Property 'field-initialization-errors/Ref_Ctor.a' has no initializer",
+    "TS2564: Property 'field-initialization-errors/Ref_InlineCtor.a' has no initializer",
     "TS2564: Property 'field-initialization-errors/Ref_Ctor_Branch.a' has no initializer",
     "TS2565: Property 'field-initialization-errors/Ref_Ctor_Use_Init.a' is used before being assigned.",
     "TS2564: Property 'field-initialization-errors/Ref_Ctor_Call_Init.a' has no initializer",

tests/compiler/field-initialization-errors.ts

@@ -16,6 +16,16 @@ class Ref_Ctor {
   new Ref_Ctor();
 }
 
+// Uninitialized with inline ctor
+class Ref_InlineCtor {
+  a: ArrayBuffer; // TS2564
+  @inline constructor() {
+  }
+}
+{
+  new Ref_InlineCtor();
+}
+
 // Uninitialized in any branch
 class Ref_Ctor_Branch {
   a: ArrayBuffer; // TS2564

tests/compiler/field-initialization.optimized.wat

@@ -817,6 +817,52 @@
    call $~lib/builtins/abort
    unreachable
   end
+  i32.const 4
+  i32.const 23
+  call $~lib/rt/stub/__alloc
+  local.tee $0
+  i32.const 0
+  i32.const 0
+  call $~lib/rt/stub/__alloc
+  i32.store
+  local.get $0
+  i32.load
+  i32.eqz
+  if
+   i32.const 0
+   i32.const 1040
+   i32.const 218
+   i32.const 3
+   call $~lib/builtins/abort
+   unreachable
+  end
+  i32.const 4
+  i32.const 24
+  call $~lib/rt/stub/__alloc
+  local.tee $0
+  i32.const 0
+  i32.store
+  i32.const 0
+  i32.const 0
+  call $~lib/rt/stub/__alloc
+  local.set $1
+  local.get $0
+  i32.load
+  drop
+  local.get $0
+  local.get $1
+  i32.store
+  local.get $0
+  i32.load
+  i32.eqz
+  if
+   i32.const 0
+   i32.const 1040
+   i32.const 230
+   i32.const 3
+   call $~lib/builtins/abort
+   unreachable
+  end
  )
  (func $~start
   call $start:field-initialization

tests/compiler/field-initialization.ts

@@ -204,3 +204,28 @@ class Flow_Balanced {
   let o = new Flow_Balanced(true);
   assert(o.a != null);
 }
+
+// inlined ctors
+
+class Ref_Init_InlineCtor {
+  a: ArrayBuffer = new ArrayBuffer(0); // OK
+  @inline
+  constructor() {
+  }
+}
+{
+  let o = new Ref_Init_InlineCtor();
+  assert(o.a != null);
+}
+
+class Ref_InlineCtor_Init {
+  a: ArrayBuffer; // OK (in ctor)
+  @inline
+  constructor() {
+    this.a = new ArrayBuffer(0);
+  }
+}
+{
+  let o = new Ref_InlineCtor_Init();
+  assert(o.a != null);
+}

tests/compiler/field-initialization.untouched.wat

@@ -1583,6 +1583,81 @@
   end
   local.get $4
   call $~lib/rt/stub/__release
+  i32.const 0
+  local.set $1
+  local.get $1
+  i32.eqz
+  if
+   i32.const 4
+   i32.const 23
+   call $~lib/rt/stub/__alloc
+   call $~lib/rt/stub/__retain
+   local.set $1
+  end
+  local.get $1
+  i32.const 0
+  i32.const 0
+  call $~lib/arraybuffer/ArrayBuffer#constructor
+  i32.store
+  local.get $1
+  local.set $1
+  local.get $1
+  i32.load
+  i32.const 0
+  i32.ne
+  i32.eqz
+  if
+   i32.const 0
+   i32.const 32
+   i32.const 218
+   i32.const 3
+   call $~lib/builtins/abort
+   unreachable
+  end
+  local.get $1
+  call $~lib/rt/stub/__release
+  i32.const 0
+  local.set $0
+  local.get $0
+  i32.eqz
+  if
+   i32.const 4
+   i32.const 24
+   call $~lib/rt/stub/__alloc
+   call $~lib/rt/stub/__retain
+   local.set $0
+  end
+  local.get $0
+  i32.const 0
+  i32.store
+  local.get $0
+  local.tee $2
+  i32.const 0
+  i32.const 0
+  call $~lib/arraybuffer/ArrayBuffer#constructor
+  local.set $3
+  local.get $2
+  i32.load
+  call $~lib/rt/stub/__release
+  local.get $3
+  i32.store
+  local.get $0
+  local.set $0
+  local.get $0
+  i32.load
+  i32.const 0
+  i32.ne
+  i32.eqz
+  if
+   i32.const 0
+   i32.const 32
+   i32.const 230
+   i32.const 3
+   call $~lib/builtins/abort
+   unreachable
+  end
+  local.get $0
+  call $~lib/rt/stub/__release
  )
  (func $~start
   call $start:field-initialization