microsoft
diff --git a/‎src/compiler/checker.ts
Copy file name to clipboard
+23-3Lines changed: 23 additions & 3 deletions b/‎src/compiler/checker.ts
Copy file name to clipboard
+23-3Lines changed: 23 additions & 3 deletions
diff --git a/‎tests/baselines/reference/objectSpread.js
Copy file name to clipboard
+62Lines changed: 62 additions & 0 deletions b/‎tests/baselines/reference/objectSpread.js
Copy file name to clipboard
+62Lines changed: 62 additions & 0 deletions
diff --git a/‎tests/baselines/reference/objectSpread.symbols
Copy file name to clipboard
+181Lines changed: 181 additions & 0 deletions b/‎tests/baselines/reference/objectSpread.symbols
Copy file name to clipboard
+181Lines changed: 181 additions & 0 deletions
@@ -4639,7 +4639,7 @@ namespace ts {
             let type: Type | undefined;
             if (pattern.kind === SyntaxKind.ObjectBindingPattern) {
                 if (declaration.dotDotDotToken) {
-                    if (parentType.flags & TypeFlags.Unknown || !isValidSpreadType(parentType)) {
+                    if (parentType.flags & TypeFlags.Unknown || !isValidSpreadType(parentType) || isGenericObjectType(parentType)) {
                         error(declaration, Diagnostics.Rest_types_may_only_be_created_from_object_types);
                         return errorType;
                     }
@@ -9842,6 +9842,10 @@ namespace ts {
             return symbol ? getLocalTypeParametersOfClassOrInterfaceOrTypeAlias(symbol) : undefined;
         }
 
+        function isNonGenericObjectType(type: Type) {
+            return !!(type.flags & TypeFlags.Object) && !isGenericMappedType(type);
+        }
+
         /**
          * Since the source of spread types are object literals, which are not binary,
          * this function should be called in a left folding style, with left = previous result of getSpreadType
@@ -9870,6 +9874,23 @@ namespace ts {
                 return left;
             }
 
+            if (isGenericObjectType(left) || isGenericObjectType(right)) {
+                if (isEmptyObjectType(left)) {
+                    return right;
+                }
+                // When the left type is an intersection, we may need to merge the last constituent of the
+                // intersection with the right type. For example when the left type is 'T & { a: string }'
+                // and the right type is '{ b: string }' we produce 'T & { a: string, b: string }'.
+                if (left.flags & TypeFlags.Intersection) {
+                    const types = (<IntersectionType>left).types;
+                    const lastLeft = types[types.length - 1];
+                    if (isNonGenericObjectType(lastLeft) && isNonGenericObjectType(right)) {
+                        return getIntersectionType(concatenate(types.slice(0, types.length - 1), [getSpreadType(lastLeft, right, symbol, typeFlags, objectFlags)]));
+                    }
+                }
+                return getIntersectionType([left, right]);
+            }
+
             const members = createSymbolTable();
             const skippedPrivateMembers = createUnderscoreEscapedMap<boolean>();
             let stringIndexInfo: IndexInfo | undefined;
@@ -17700,9 +17721,8 @@ namespace ts {
         }
 
         function isValidSpreadType(type: Type): boolean {
-            return !!(type.flags & (TypeFlags.AnyOrUnknown | TypeFlags.NonPrimitive) ||
+            return !!(type.flags & (TypeFlags.AnyOrUnknown | TypeFlags.NonPrimitive | TypeFlags.Object | TypeFlags.InstantiableNonPrimitive) ||
                 getFalsyFlags(type) & TypeFlags.DefinitelyFalsy && isValidSpreadType(removeDefinitelyFalsyTypes(type)) ||
-                type.flags & TypeFlags.Object && !isGenericMappedType(type) ||
                 type.flags & TypeFlags.UnionOrIntersection && every((<UnionOrIntersectionType>type).types, isValidSpreadType));
         }
 
 
@@ -119,6 +119,41 @@ let a = 12;
 let shortCutted: { a: number, b: string } = { ...o, a }
 // non primitive
 let spreadNonPrimitive = { ...<object>{}};
+
+// generic spreads
+
+function f<T, U>(t: T, u: U) {
+    return { ...t, ...u, id: 'id' };
+}
+
+let exclusive: { id: string, a: number, b: string, c: string, d: boolean } =
+    f({ a: 1, b: 'yes' }, { c: 'no', d: false })
+let overlap: { id: string, a: number, b: string } =
+    f({ a: 1 }, { a: 2, b: 'extra' })
+let overlapConflict: { id:string, a: string } =
+    f({ a: 1 }, { a: 'mismatch' })
+let overwriteId: { id: string, a: number, c: number, d: string } =
+    f({ a: 1, id: true }, { c: 1, d: 'no' })
+
+function genericSpread<T, U>(t: T, u: U, v: T | U, w: T | { s: string }, obj: { x: number }) {
+    let x01 = { ...t };
+    let x02 = { ...t, ...t };
+    let x03 = { ...t, ...u };
+    let x04 = { ...u, ...t };
+    let x05 = { a: 5, b: 'hi', ...t };
+    let x06 = { ...t, a: 5, b: 'hi' };
+    let x07 = { a: 5, b: 'hi', ...t, c: true, ...obj };
+    let x09 = { a: 5, ...t, b: 'hi', c: true, ...obj };
+    let x10 = { a: 5, ...t, b: 'hi', ...u, ...obj };
+    let x11 = { ...v };
+    let x12 = { ...v, ...obj };
+    let x13 = { ...w };
+    let x14 = { ...w, ...obj };
+    let x15 = { ...t, ...v };
+    let x16 = { ...t, ...w };
+    let x17 = { ...t, ...w, ...obj };
+    let x18 = { ...t, ...v, ...w };
+}
 
 
 //// [objectSpread.js]
@@ -214,3 +249,30 @@ var a = 12;
 var shortCutted = __assign({}, o, { a: a });
 // non primitive
 var spreadNonPrimitive = __assign({}, {});
+// generic spreads
+function f(t, u) {
+    return __assign({}, t, u, { id: 'id' });
+}
+var exclusive = f({ a: 1, b: 'yes' }, { c: 'no', d: false });
+var overlap = f({ a: 1 }, { a: 2, b: 'extra' });
+var overlapConflict = f({ a: 1 }, { a: 'mismatch' });
+var overwriteId = f({ a: 1, id: true }, { c: 1, d: 'no' });
+function genericSpread(t, u, v, w, obj) {
+    var x01 = __assign({}, t);
+    var x02 = __assign({}, t, t);
+    var x03 = __assign({}, t, u);
+    var x04 = __assign({}, u, t);
+    var x05 = __assign({ a: 5, b: 'hi' }, t);
+    var x06 = __assign({}, t, { a: 5, b: 'hi' });
+    var x07 = __assign({ a: 5, b: 'hi' }, t, { c: true }, obj);
+    var x09 = __assign({ a: 5 }, t, { b: 'hi', c: true }, obj);
+    var x10 = __assign({ a: 5 }, t, { b: 'hi' }, u, obj);
+    var x11 = __assign({}, v);
+    var x12 = __assign({}, v, obj);
+    var x13 = __assign({}, w);
+    var x14 = __assign({}, w, obj);
+    var x15 = __assign({}, t, v);
+    var x16 = __assign({}, t, w);
+    var x17 = __assign({}, t, w, obj);
+    var x18 = __assign({}, t, v, w);
+}
@@ -452,3 +452,184 @@ let shortCutted: { a: number, b: string } = { ...o, a }
 let spreadNonPrimitive = { ...<object>{}};
 >spreadNonPrimitive : Symbol(spreadNonPrimitive, Decl(objectSpread.ts, 119, 3))
 
+// generic spreads
+
+function f<T, U>(t: T, u: U) {
+>f : Symbol(f, Decl(objectSpread.ts, 119, 42))
+>T : Symbol(T, Decl(objectSpread.ts, 123, 11))
+>U : Symbol(U, Decl(objectSpread.ts, 123, 13))
+>t : Symbol(t, Decl(objectSpread.ts, 123, 17))
+>T : Symbol(T, Decl(objectSpread.ts, 123, 11))
+>u : Symbol(u, Decl(objectSpread.ts, 123, 22))
+>U : Symbol(U, Decl(objectSpread.ts, 123, 13))
+
+    return { ...t, ...u, id: 'id' };
+>t : Symbol(t, Decl(objectSpread.ts, 123, 17))
+>u : Symbol(u, Decl(objectSpread.ts, 123, 22))
+>id : Symbol(id, Decl(objectSpread.ts, 124, 24))
+}
+
+let exclusive: { id: string, a: number, b: string, c: string, d: boolean } =
+>exclusive : Symbol(exclusive, Decl(objectSpread.ts, 127, 3))
+>id : Symbol(id, Decl(objectSpread.ts, 127, 16))
+>a : Symbol(a, Decl(objectSpread.ts, 127, 28))
+>b : Symbol(b, Decl(objectSpread.ts, 127, 39))
+>c : Symbol(c, Decl(objectSpread.ts, 127, 50))
+>d : Symbol(d, Decl(objectSpread.ts, 127, 61))
+
+    f({ a: 1, b: 'yes' }, { c: 'no', d: false })
+>f : Symbol(f, Decl(objectSpread.ts, 119, 42))
+>a : Symbol(a, Decl(objectSpread.ts, 128, 7))
+>b : Symbol(b, Decl(objectSpread.ts, 128, 13))
+>c : Symbol(c, Decl(objectSpread.ts, 128, 27))
+>d : Symbol(d, Decl(objectSpread.ts, 128, 36))
+
+let overlap: { id: string, a: number, b: string } =
+>overlap : Symbol(overlap, Decl(objectSpread.ts, 129, 3))
+>id : Symbol(id, Decl(objectSpread.ts, 129, 14))
+>a : Symbol(a, Decl(objectSpread.ts, 129, 26))
+>b : Symbol(b, Decl(objectSpread.ts, 129, 37))
+
+    f({ a: 1 }, { a: 2, b: 'extra' })
+>f : Symbol(f, Decl(objectSpread.ts, 119, 42))
+>a : Symbol(a, Decl(objectSpread.ts, 130, 7))
+>a : Symbol(a, Decl(objectSpread.ts, 130, 17))
+>b : Symbol(b, Decl(objectSpread.ts, 130, 23))
+
+let overlapConflict: { id:string, a: string } =
+>overlapConflict : Symbol(overlapConflict, Decl(objectSpread.ts, 131, 3))
+>id : Symbol(id, Decl(objectSpread.ts, 131, 22))
+>a : Symbol(a, Decl(objectSpread.ts, 131, 33))
+
+    f({ a: 1 }, { a: 'mismatch' })
+>f : Symbol(f, Decl(objectSpread.ts, 119, 42))
+>a : Symbol(a, Decl(objectSpread.ts, 132, 7))
+>a : Symbol(a, Decl(objectSpread.ts, 132, 17))
+
+let overwriteId: { id: string, a: number, c: number, d: string } =
+>overwriteId : Symbol(overwriteId, Decl(objectSpread.ts, 133, 3))
+>id : Symbol(id, Decl(objectSpread.ts, 133, 18))
+>a : Symbol(a, Decl(objectSpread.ts, 133, 30))
+>c : Symbol(c, Decl(objectSpread.ts, 133, 41))
+>d : Symbol(d, Decl(objectSpread.ts, 133, 52))
+
+    f({ a: 1, id: true }, { c: 1, d: 'no' })
+>f : Symbol(f, Decl(objectSpread.ts, 119, 42))
+>a : Symbol(a, Decl(objectSpread.ts, 134, 7))
+>id : Symbol(id, Decl(objectSpread.ts, 134, 13))
+>c : Symbol(c, Decl(objectSpread.ts, 134, 27))
+>d : Symbol(d, Decl(objectSpread.ts, 134, 33))
+
+function genericSpread<T, U>(t: T, u: U, v: T | U, w: T | { s: string }, obj: { x: number }) {
+>genericSpread : Symbol(genericSpread, Decl(objectSpread.ts, 134, 44))
+>T : Symbol(T, Decl(objectSpread.ts, 136, 23))
+>U : Symbol(U, Decl(objectSpread.ts, 136, 25))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>T : Symbol(T, Decl(objectSpread.ts, 136, 23))
+>u : Symbol(u, Decl(objectSpread.ts, 136, 34))
+>U : Symbol(U, Decl(objectSpread.ts, 136, 25))
+>v : Symbol(v, Decl(objectSpread.ts, 136, 40))
+>T : Symbol(T, Decl(objectSpread.ts, 136, 23))
+>U : Symbol(U, Decl(objectSpread.ts, 136, 25))
+>w : Symbol(w, Decl(objectSpread.ts, 136, 50))
+>T : Symbol(T, Decl(objectSpread.ts, 136, 23))
+>s : Symbol(s, Decl(objectSpread.ts, 136, 59))
+>obj : Symbol(obj, Decl(objectSpread.ts, 136, 72))
+>x : Symbol(x, Decl(objectSpread.ts, 136, 79))
+
+    let x01 = { ...t };
+>x01 : Symbol(x01, Decl(objectSpread.ts, 137, 7))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+
+    let x02 = { ...t, ...t };
+>x02 : Symbol(x02, Decl(objectSpread.ts, 138, 7))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+
+    let x03 = { ...t, ...u };
+>x03 : Symbol(x03, Decl(objectSpread.ts, 139, 7))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>u : Symbol(u, Decl(objectSpread.ts, 136, 34))
+
+    let x04 = { ...u, ...t };
+>x04 : Symbol(x04, Decl(objectSpread.ts, 140, 7))
+>u : Symbol(u, Decl(objectSpread.ts, 136, 34))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+
+    let x05 = { a: 5, b: 'hi', ...t };
+>x05 : Symbol(x05, Decl(objectSpread.ts, 141, 7))
+>a : Symbol(a, Decl(objectSpread.ts, 141, 15))
+>b : Symbol(b, Decl(objectSpread.ts, 141, 21))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+
+    let x06 = { ...t, a: 5, b: 'hi' };
+>x06 : Symbol(x06, Decl(objectSpread.ts, 142, 7))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>a : Symbol(a, Decl(objectSpread.ts, 142, 21))
+>b : Symbol(b, Decl(objectSpread.ts, 142, 27))
+
+    let x07 = { a: 5, b: 'hi', ...t, c: true, ...obj };
+>x07 : Symbol(x07, Decl(objectSpread.ts, 143, 7))
+>a : Symbol(a, Decl(objectSpread.ts, 143, 15))
+>b : Symbol(b, Decl(objectSpread.ts, 143, 21))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>c : Symbol(c, Decl(objectSpread.ts, 143, 36))
+>obj : Symbol(obj, Decl(objectSpread.ts, 136, 72))
+
+    let x09 = { a: 5, ...t, b: 'hi', c: true, ...obj };
+>x09 : Symbol(x09, Decl(objectSpread.ts, 144, 7))
+>a : Symbol(a, Decl(objectSpread.ts, 144, 15))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>b : Symbol(b, Decl(objectSpread.ts, 144, 27))
+>c : Symbol(c, Decl(objectSpread.ts, 144, 36))
+>obj : Symbol(obj, Decl(objectSpread.ts, 136, 72))
+
+    let x10 = { a: 5, ...t, b: 'hi', ...u, ...obj };
+>x10 : Symbol(x10, Decl(objectSpread.ts, 145, 7))
+>a : Symbol(a, Decl(objectSpread.ts, 145, 15))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>b : Symbol(b, Decl(objectSpread.ts, 145, 27))
+>u : Symbol(u, Decl(objectSpread.ts, 136, 34))
+>obj : Symbol(obj, Decl(objectSpread.ts, 136, 72))
+
+    let x11 = { ...v };
+>x11 : Symbol(x11, Decl(objectSpread.ts, 146, 7))
+>v : Symbol(v, Decl(objectSpread.ts, 136, 40))
+
+    let x12 = { ...v, ...obj };
+>x12 : Symbol(x12, Decl(objectSpread.ts, 147, 7))
+>v : Symbol(v, Decl(objectSpread.ts, 136, 40))
+>obj : Symbol(obj, Decl(objectSpread.ts, 136, 72))
+
+    let x13 = { ...w };
+>x13 : Symbol(x13, Decl(objectSpread.ts, 148, 7))
+>w : Symbol(w, Decl(objectSpread.ts, 136, 50))
+
+    let x14 = { ...w, ...obj };
+>x14 : Symbol(x14, Decl(objectSpread.ts, 149, 7))
+>w : Symbol(w, Decl(objectSpread.ts, 136, 50))
+>obj : Symbol(obj, Decl(objectSpread.ts, 136, 72))
+
+    let x15 = { ...t, ...v };
+>x15 : Symbol(x15, Decl(objectSpread.ts, 150, 7))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>v : Symbol(v, Decl(objectSpread.ts, 136, 40))
+
+    let x16 = { ...t, ...w };
+>x16 : Symbol(x16, Decl(objectSpread.ts, 151, 7))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>w : Symbol(w, Decl(objectSpread.ts, 136, 50))
+
+    let x17 = { ...t, ...w, ...obj };
+>x17 : Symbol(x17, Decl(objectSpread.ts, 152, 7))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>w : Symbol(w, Decl(objectSpread.ts, 136, 50))
+>obj : Symbol(obj, Decl(objectSpread.ts, 136, 72))
+
+    let x18 = { ...t, ...v, ...w };
+>x18 : Symbol(x18, Decl(objectSpread.ts, 153, 7))
+>t : Symbol(t, Decl(objectSpread.ts, 136, 29))
+>v : Symbol(v, Decl(objectSpread.ts, 136, 40))
+>w : Symbol(w, Decl(objectSpread.ts, 136, 50))
+}
+