fix(44448): Non-optional but undefined delete under exactOptionalPropertyTypes

src/compiler/checker.ts

@@ -31276,8 +31276,9 @@ namespace ts {
         }
 
         function checkDeleteExpressionMustBeOptional(expr: AccessExpression, type: Type) {
-            const AnyOrUnknownOrNeverFlags = TypeFlags.AnyOrUnknown | TypeFlags.Never;
-            if (strictNullChecks && !(type.flags & AnyOrUnknownOrNeverFlags) && !(getFalsyFlags(type) & TypeFlags.Undefined)) {
+            if (strictNullChecks &&
+                !(type.flags & (TypeFlags.AnyOrUnknown | TypeFlags.Never)) &&
+                !(exactOptionalPropertyTypes ? 0 : getFalsyFlags(type) & TypeFlags.Undefined)) {
                 error(expr, Diagnostics.The_operand_of_a_delete_operator_must_be_optional);
             }
         }

src/testRunner/compilerRunner.ts

@@ -136,6 +136,7 @@ namespace Harness {
             "skipDefaultLibCheck",
             "preserveConstEnums",
             "skipLibCheck",
+            "exactOptionalPropertyTypes"
         ];
         private fileName: string;
         private justName: string;

tests/baselines/reference/deleteExpressionMustBeOptional(strict=false).errors.txt

@@ -43,4 +43,5 @@ tests/cases/compiler/deleteExpressionMustBeOptional.ts(34,10): error TS2339: Pro
     delete a.b
 
     delete b.a
-    delete b.b
+    delete b.b
+

tests/baselines/reference/deleteExpressionMustBeOptional(strict=false).js

@@ -38,7 +38,8 @@ delete a.a
 delete a.b
 
 delete b.a
-delete b.b
+delete b.b
+
 
 //// [deleteExpressionMustBeOptional.js]
 delete f.a;

tests/baselines/reference/deleteExpressionMustBeOptional(strict=true).errors.txt

@@ -49,4 +49,5 @@ tests/cases/compiler/deleteExpressionMustBeOptional.ts(34,10): error TS2339: Pro
     delete a.b
 
     delete b.a
-    delete b.b
+    delete b.b
+

tests/baselines/reference/deleteExpressionMustBeOptional(strict=true).js

@@ -38,7 +38,8 @@ delete a.a
 delete a.b
 
 delete b.a
-delete b.b
+delete b.b
+
 
 //// [deleteExpressionMustBeOptional.js]
 "use strict";

tests/baselines/reference/deleteExpressionMustBeOptional_exactOptionalPropertyTypes(exactoptionalpropertytypes=false).errors.txt

@@ -0,0 +1,53 @@
+tests/cases/compiler/deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts(25,8): error TS2790: The operand of a 'delete' operator must be optional.
+tests/cases/compiler/deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts(27,8): error TS2790: The operand of a 'delete' operator must be optional.
+tests/cases/compiler/deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts(34,10): error TS2339: Property 'j' does not exist on type 'Foo'.
+
+
+==== tests/cases/compiler/deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts (3 errors) ====
+    interface Foo {
+        a: number
+        b: number | undefined
+        c: number | null
+        d?: number
+        e: number | undefined | null
+        f?: number | undefined | null
+        g: unknown
+        h: any
+        i: never
+    }
+
+    interface AA {
+        [s: string]: number
+    }
+
+    type BB = {
+        [P in keyof any]: number
+    }
+
+    declare const f: Foo
+    declare const a: AA
+    declare const b: BB
+
+    delete f.a
+           ~~~
+!!! error TS2790: The operand of a 'delete' operator must be optional.
+    delete f.b
+    delete f.c
+           ~~~
+!!! error TS2790: The operand of a 'delete' operator must be optional.
+    delete f.d
+    delete f.e
+    delete f.f
+    delete f.g
+    delete f.h
+    delete f.i
+    delete f.j
+             ~
+!!! error TS2339: Property 'j' does not exist on type 'Foo'.
+
+    delete a.a
+    delete a.b
+
+    delete b.a
+    delete b.b
+

tests/baselines/reference/deleteExpressionMustBeOptional_exactOptionalPropertyTypes(exactoptionalpropertytypes=false).js

@@ -0,0 +1,58 @@
+//// [deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts]
+interface Foo {
+    a: number
+    b: number | undefined
+    c: number | null
+    d?: number
+    e: number | undefined | null
+    f?: number | undefined | null
+    g: unknown
+    h: any
+    i: never
+}
+
+interface AA {
+    [s: string]: number
+}
+
+type BB = {
+    [P in keyof any]: number
+}
+
+declare const f: Foo
+declare const a: AA
+declare const b: BB
+
+delete f.a
+delete f.b
+delete f.c
+delete f.d
+delete f.e
+delete f.f
+delete f.g
+delete f.h
+delete f.i
+delete f.j
+
+delete a.a
+delete a.b
+
+delete b.a
+delete b.b
+
+
+//// [deleteExpressionMustBeOptional_exactOptionalPropertyTypes.js]
+delete f.a;
+delete f.b;
+delete f.c;
+delete f.d;
+delete f.e;
+delete f.f;
+delete f.g;
+delete f.h;
+delete f.i;
+delete f.j;
+delete a.a;
+delete a.b;
+delete b.a;
+delete b.b;

tests/baselines/reference/deleteExpressionMustBeOptional_exactOptionalPropertyTypes(exactoptionalpropertytypes=false).symbols

@@ -0,0 +1,118 @@
+=== tests/cases/compiler/deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts ===
+interface Foo {
+>Foo : Symbol(Foo, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 0, 0))
+
+    a: number
+>a : Symbol(Foo.a, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 0, 15))
+
+    b: number | undefined
+>b : Symbol(Foo.b, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 1, 13))
+
+    c: number | null
+>c : Symbol(Foo.c, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 2, 25))
+
+    d?: number
+>d : Symbol(Foo.d, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 3, 20))
+
+    e: number | undefined | null
+>e : Symbol(Foo.e, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 4, 14))
+
+    f?: number | undefined | null
+>f : Symbol(Foo.f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 5, 32))
+
+    g: unknown
+>g : Symbol(Foo.g, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 6, 33))
+
+    h: any
+>h : Symbol(Foo.h, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 7, 14))
+
+    i: never
+>i : Symbol(Foo.i, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 8, 10))
+}
+
+interface AA {
+>AA : Symbol(AA, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 10, 1))
+
+    [s: string]: number
+>s : Symbol(s, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 13, 5))
+}
+
+type BB = {
+>BB : Symbol(BB, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 14, 1))
+
+    [P in keyof any]: number
+>P : Symbol(P, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 17, 5))
+}
+
+declare const f: Foo
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>Foo : Symbol(Foo, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 0, 0))
+
+declare const a: AA
+>a : Symbol(a, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 21, 13))
+>AA : Symbol(AA, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 10, 1))
+
+declare const b: BB
+>b : Symbol(b, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 22, 13))
+>BB : Symbol(BB, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 14, 1))
+
+delete f.a
+>f.a : Symbol(Foo.a, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 0, 15))
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>a : Symbol(Foo.a, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 0, 15))
+
+delete f.b
+>f.b : Symbol(Foo.b, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 1, 13))
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>b : Symbol(Foo.b, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 1, 13))
+
+delete f.c
+>f.c : Symbol(Foo.c, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 2, 25))
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>c : Symbol(Foo.c, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 2, 25))
+
+delete f.d
+>f.d : Symbol(Foo.d, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 3, 20))
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>d : Symbol(Foo.d, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 3, 20))
+
+delete f.e
+>f.e : Symbol(Foo.e, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 4, 14))
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>e : Symbol(Foo.e, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 4, 14))
+
+delete f.f
+>f.f : Symbol(Foo.f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 5, 32))
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>f : Symbol(Foo.f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 5, 32))
+
+delete f.g
+>f.g : Symbol(Foo.g, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 6, 33))
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>g : Symbol(Foo.g, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 6, 33))
+
+delete f.h
+>f.h : Symbol(Foo.h, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 7, 14))
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>h : Symbol(Foo.h, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 7, 14))
+
+delete f.i
+>f.i : Symbol(Foo.i, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 8, 10))
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+>i : Symbol(Foo.i, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 8, 10))
+
+delete f.j
+>f : Symbol(f, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 20, 13))
+
+delete a.a
+>a : Symbol(a, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 21, 13))
+
+delete a.b
+>a : Symbol(a, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 21, 13))
+
+delete b.a
+>b : Symbol(b, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 22, 13))
+
+delete b.b
+>b : Symbol(b, Decl(deleteExpressionMustBeOptional_exactOptionalPropertyTypes.ts, 22, 13))
+