From 39d1c8b84490eb1da66ef15396188430635723c6 Mon Sep 17 00:00:00 2001
From: kpreisser <kpreisser@users.noreply.github.com>
Date: Sun, 5 Mar 2017 14:25:59 +0100
Subject: [PATCH 1/2] Allow the right-hand side of an 'in' expression to be of
 non-primitive object type. Fixes #14269

---
 src/compiler/checker.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index a4c0acc405d5e..300fc2e8beffa 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -15546,7 +15546,7 @@ namespace ts {
             if (!(isTypeComparableTo(leftType, stringType) || isTypeOfKind(leftType, TypeFlags.NumberLike | TypeFlags.ESSymbol))) {
                 error(left, Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
             }
-            if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeVariable)) {
+            if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeVariable | TypeFlags.NonPrimitive)) {
                 error(right, Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
             }
             return booleanType;

From 6d02d1fde8ef223b9ac828603112953e8f697df1 Mon Sep 17 00:00:00 2001
From: kpreisser <kpreisser@users.noreply.github.com>
Date: Sun, 5 Mar 2017 14:38:16 +0100
Subject: [PATCH 2/2] Add tests.

---
 .../nonPrimitiveRhsSideOfInExpression.js      | 17 +++++++++++++
 .../nonPrimitiveRhsSideOfInExpression.symbols | 18 +++++++++++++
 .../nonPrimitiveRhsSideOfInExpression.types   | 25 +++++++++++++++++++
 .../nonPrimitiveRhsSideOfInExpression.ts      |  8 ++++++
 4 files changed, 68 insertions(+)
 create mode 100644 tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.js
 create mode 100644 tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.symbols
 create mode 100644 tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.types
 create mode 100644 tests/cases/conformance/types/nonPrimitive/nonPrimitiveRhsSideOfInExpression.ts

diff --git a/tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.js b/tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.js
new file mode 100644
index 0000000000000..4b08610199be9
--- /dev/null
+++ b/tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.js
@@ -0,0 +1,17 @@
+//// [nonPrimitiveRhsSideOfInExpression.ts]
+let o: object = {};
+
+function f(): object {
+	return {};
+}
+
+const b1 = "foo" in o;
+const b2 = "bar" in f();
+
+//// [nonPrimitiveRhsSideOfInExpression.js]
+var o = {};
+function f() {
+    return {};
+}
+var b1 = "foo" in o;
+var b2 = "bar" in f();
diff --git a/tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.symbols b/tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.symbols
new file mode 100644
index 0000000000000..914f77322a53f
--- /dev/null
+++ b/tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.symbols
@@ -0,0 +1,18 @@
+=== tests/cases/conformance/types/nonPrimitive/nonPrimitiveRhsSideOfInExpression.ts ===
+let o: object = {};
+>o : Symbol(o, Decl(nonPrimitiveRhsSideOfInExpression.ts, 0, 3))
+
+function f(): object {
+>f : Symbol(f, Decl(nonPrimitiveRhsSideOfInExpression.ts, 0, 19))
+
+	return {};
+}
+
+const b1 = "foo" in o;
+>b1 : Symbol(b1, Decl(nonPrimitiveRhsSideOfInExpression.ts, 6, 5))
+>o : Symbol(o, Decl(nonPrimitiveRhsSideOfInExpression.ts, 0, 3))
+
+const b2 = "bar" in f();
+>b2 : Symbol(b2, Decl(nonPrimitiveRhsSideOfInExpression.ts, 7, 5))
+>f : Symbol(f, Decl(nonPrimitiveRhsSideOfInExpression.ts, 0, 19))
+
diff --git a/tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.types b/tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.types
new file mode 100644
index 0000000000000..45c8864e43e4c
--- /dev/null
+++ b/tests/baselines/reference/nonPrimitiveRhsSideOfInExpression.types
@@ -0,0 +1,25 @@
+=== tests/cases/conformance/types/nonPrimitive/nonPrimitiveRhsSideOfInExpression.ts ===
+let o: object = {};
+>o : object
+>{} : {}
+
+function f(): object {
+>f : () => object
+
+	return {};
+>{} : {}
+}
+
+const b1 = "foo" in o;
+>b1 : boolean
+>"foo" in o : boolean
+>"foo" : "foo"
+>o : object
+
+const b2 = "bar" in f();
+>b2 : boolean
+>"bar" in f() : boolean
+>"bar" : "bar"
+>f() : object
+>f : () => object
+
diff --git a/tests/cases/conformance/types/nonPrimitive/nonPrimitiveRhsSideOfInExpression.ts b/tests/cases/conformance/types/nonPrimitive/nonPrimitiveRhsSideOfInExpression.ts
new file mode 100644
index 0000000000000..f2a02c7a59afb
--- /dev/null
+++ b/tests/cases/conformance/types/nonPrimitive/nonPrimitiveRhsSideOfInExpression.ts
@@ -0,0 +1,8 @@
+let o: object = {};
+
+function f(): object {
+	return {};
+}
+
+const b1 = "foo" in o;
+const b2 = "bar" in f();
\ No newline at end of file