feat: capture reassignable variable and mutable objects

examples/tests/valid/capture_mutables.w

@@ -0,0 +1,16 @@
+let a = MutArray<str>["hello"];
+let s = MutSet<num>{12};
+let m = MutMap<bool>{"hello": true};
+
+let aCloned = (Array<str>["hello"]).copyMut();
+
+let handler = inflight () => {
+  assert(a.length == 1);
+  assert(s.size == 1);
+  assert(m.size() == 1);
+  assert(aCloned.length == 1);
+};
+
+test "main" {
+  handler();
+}

examples/tests/valid/capture_reassigable_class_field.w

@@ -0,0 +1,38 @@
+bring cloud;
+class KeyValueStore {
+  bucket: cloud.Bucket;
+  var onUpdateCallback : inflight (str): void;
+  init(store: cloud.Bucket) {
+    this.bucket = store;
+    this.onUpdateCallback = inflight (k: str) => {};
+  }
+
+  onUpdate(fn: inflight (str):void){
+    this.onUpdateCallback = fn;
+  }
+
+  inflight get(key: str): Json {
+    return this.bucket.getJson(key);
+  }
+  inflight set(key: str, value: Json): void {
+    this.onUpdateCallback(key);
+    this.bucket.putJson(key, value);
+  }
+}
+
+let kv = new KeyValueStore(new cloud.Bucket());
+let counter = new cloud.Counter();
+kv.onUpdate(inflight (key: str): void => {
+  counter.inc(1, key);
+});
+
+test "main" {
+  kv.set("k", Json { 
+    value: "v" 
+  });
+  kv.get("k");
+  kv.get("k");
+  kv.get("k2");
+  assert(counter.peek("k") == 2);
+  assert(counter.peek("k2") == 1);
+}

examples/tests/valid/capture_reassignable.w

@@ -0,0 +1,12 @@
+bring cloud;
+
+let var x = 5;
+
+let handler = inflight (): void => {
+    assert(x == 5);
+
+};
+
+test "main" {
+    handler();
+}

libs/wingc/src/jsify.rs

@@ -1359,7 +1359,7 @@ impl<'a> JSifier<'a> {
 				.filter(|(_, kind, _)| {
 					let var = kind.as_variable().unwrap();
 					// We capture preflight non-reassignable fields
-					var.phase != Phase::Inflight && !var.reassignable && var.type_.is_capturable()
+					var.phase != Phase::Inflight && var.type_.is_capturable()
 				})
 				.map(|(name, ..)| name)
 				.collect_vec()
@@ -1541,19 +1541,8 @@ impl<'ast> Visit<'ast> for FieldReferenceVisitor<'ast> {
 					}
 
 					// now we need to verify that the component can be captured.
-					// (1) non-reassignable
 					// (2) capturable type (immutable/resource).
 
-					// if the variable is reassignable, bail out
-					if variable.reassignable {
-						report_diagnostic(Diagnostic {
-							message: format!("Cannot capture reassignable field '{curr}'"),
-							span: Some(curr.span.clone()),
-						});
-
-						return;
-					}
-
 					// if this type is not capturable, bail out
 					if !variable.type_.is_capturable() {
 						report_diagnostic(Diagnostic {

libs/wingc/src/type_check.rs

@@ -894,10 +894,10 @@ impl TypeRef {
 			Type::Anything => false,
 			Type::Unresolved => false,
 			Type::Void => false,
-			Type::MutJson => false,
-			Type::MutArray(_) => false,
-			Type::MutMap(_) => false,
-			Type::MutSet(_) => false,
+			Type::MutJson => true,
+			Type::MutArray(v) => v.is_capturable(),
+			Type::MutMap(v) => v.is_capturable(),
+			Type::MutSet(v) => v.is_capturable(),
 			Type::Function(sig) => sig.phase == Phase::Inflight,
 
 			// only preflight classes can be captured

tools/hangar/__snapshots__/invalid.ts.snap

@@ -116,63 +116,6 @@ error: Cannot find module \\"foobar\\" in source directory: Unable to load \\"fo
 
 
 
-Tests 1 failed (1) 
-Duration <DURATION>
-"
-`;
-
-exports[`capture_mutables.w 1`] = `
-"error: Cannot capture field 'a' with non-capturable type 'MutArray<str>'
-  --> ../../../examples/tests/invalid/capture_mutables.w:8:10
-  |
-8 |   assert(a.length == 1);
-  |          ^ Cannot capture field 'a' with non-capturable type 'MutArray<str>'
-
-
-error: Cannot capture field 's' with non-capturable type 'MutSet<num>'
-   --> ../../../examples/tests/invalid/capture_mutables.w:10:10
-   |
-10 |   assert(s.size == 1);
-   |          ^ Cannot capture field 's' with non-capturable type 'MutSet<num>'
-
-
-error: Cannot capture field 'm' with non-capturable type 'MutMap<bool>'
-   --> ../../../examples/tests/invalid/capture_mutables.w:12:10
-   |
-12 |   assert(m.size() == 1);
-   |          ^ Cannot capture field 'm' with non-capturable type 'MutMap<bool>'
-
-
-error: Cannot capture field 'aCloned' with non-capturable type 'MutArray<str>'
-   --> ../../../examples/tests/invalid/capture_mutables.w:14:10
-   |
-14 |   assert(aCloned.length == 1);
-   |          ^^^^^^^ Cannot capture field 'aCloned' with non-capturable type 'MutArray<str>'
-
-
-
-
-
-
-
-Tests 1 failed (1) 
-Duration <DURATION>
-"
-`;
-
-exports[`capture_reassignable.w 1`] = `
-"error: Cannot capture reassignable field 'x'
-  --> ../../../examples/tests/invalid/capture_reassignable.w:6:15
-  |
-6 |     log(\\"x: \${x}\\");
-  |               ^ Cannot capture reassignable field 'x'
-
-
-
-
-
-
-
 Tests 1 failed (1) 
 Duration <DURATION>
 "
@@ -733,26 +676,13 @@ Duration <DURATION>
 `;
 
 exports[`inflight_class_capture_mutable.w 1`] = `
-"error: Cannot capture field 'x' with non-capturable type 'MutArray<str>'
-  --> ../../../examples/tests/invalid/inflight_class_capture_mutable.w:5:9
-  |
-5 |     log(x.at(0));
-  |         ^ Cannot capture field 'x' with non-capturable type 'MutArray<str>'
-
-
-error: Cannot capture reassignable field 'foo'
-   --> ../../../examples/tests/invalid/inflight_class_capture_mutable.w:14:12
-   |
-14 |     return foo;
-   |            ^^^ Cannot capture reassignable field 'foo'
-
-
+"pass ─ inflight_class_capture_mutable.wsim (no tests)
 
 
 
 
 
-Tests 1 failed (1) 
+Tests 1 passed (1) 
 Duration <DURATION>
 "
 `;
@@ -1503,21 +1433,7 @@ Duration <DURATION>
 `;
 
 exports[`resource_captures.w 1`] = `
-"error: Cannot capture reassignable field 'reassignable'
-   --> ../../../examples/tests/invalid/resource_captures.w:18:17
-   |
-18 |     log(\\"\${this.reassignable}\\");
-   |                 ^^^^^^^^^^^^ Cannot capture reassignable field 'reassignable'
-
-
-error: Cannot capture field 'mutArray' with non-capturable type 'MutArray<str>'
-   --> ../../../examples/tests/invalid/resource_captures.w:20:14
-   |
-20 |     log(this.mutArray.at(0));
-   |              ^^^^^^^^ Cannot capture field 'mutArray' with non-capturable type 'MutArray<str>'
-
-
-error: Unable to qualify which operations are performed on 'this.bucket' of type 'Bucket'. This is not supported yet.
+"error: Unable to qualify which operations are performed on 'this.bucket' of type 'Bucket'. This is not supported yet.
    --> ../../../examples/tests/invalid/resource_captures.w:23:13
    |
 23 |     let b = this.bucket;