Test self-assignment w/array spread in loop

Author: sandersn

tests/baselines/reference/selfReferencingSpreadInLoop.errors.txt

@@ -0,0 +1,14 @@
+tests/cases/compiler/selfReferencingSpreadInLoop.ts(1,5): error TS7034: Variable 'additional' implicitly has type 'any[]' in some locations where its type cannot be determined.
+tests/cases/compiler/selfReferencingSpreadInLoop.ts(3,22): error TS7005: Variable 'additional' implicitly has an 'any[]' type.
+
+
+==== tests/cases/compiler/selfReferencingSpreadInLoop.ts (2 errors) ====
+    let additional = [];
+        ~~~~~~~~~~
+!!! error TS7034: Variable 'additional' implicitly has type 'any[]' in some locations where its type cannot be determined.
+    for (const subcomponent of [1, 2, 3]) {
+        additional = [...additional, subcomponent];
+                         ~~~~~~~~~~
+!!! error TS7005: Variable 'additional' implicitly has an 'any[]' type.
+    }
+    

tests/baselines/reference/selfReferencingSpreadInLoop.js

@@ -0,0 +1,13 @@
+//// [selfReferencingSpreadInLoop.ts]
+let additional = [];
+for (const subcomponent of [1, 2, 3]) {
+    additional = [...additional, subcomponent];
+}
+
+
+//// [selfReferencingSpreadInLoop.js]
+var additional = [];
+for (var _i = 0, _a = [1, 2, 3]; _i < _a.length; _i++) {
+    var subcomponent = _a[_i];
+    additional = additional.concat([subcomponent]);
+}

tests/cases/compiler/selfReferencingSpreadInLoop.ts

@@ -0,0 +1,5 @@
+// @noImplicitAny: true
+let additional = [];
+for (const subcomponent of [1, 2, 3]) {
+    additional = [...additional, subcomponent];
+}