Explicitly encode keyof behaviors for never and unknown into getIndexType (#30753)

* Explicitly encode keyof behaviors for never and unknown into getIndexType

* Merge similar cases

tests/cases/compiler/complicatedIndexedAccessKeyofReliesOnKeyofNeverUpperBound.ts

@@ -0,0 +1,42 @@
+interface TextChannel {
+    id: string;
+    type: 'text';
+    phoneNumber: string;
+}
+
+interface EmailChannel {
+    id: string;
+    type: 'email';
+    addres: string;
+}
+
+type Channel = TextChannel | EmailChannel;
+
+export type ChannelType = Channel extends { type: infer R } ? R : never;
+
+type Omit<T, K extends keyof T> = Pick<
+    T,
+    ({ [P in keyof T]: P } & { [P in K]: never } & { [x: string]: never })[keyof T]
+>;
+
+type ChannelOfType<T extends ChannelType, A = Channel> = A extends { type: T }
+    ? A
+    : never;
+
+
+export type NewChannel<T extends Channel> = Pick<T, 'type'> &
+    Partial<Omit<T, 'type' | 'id'>> & { localChannelId: string };
+
+
+export function makeNewChannel<T extends ChannelType>(type: T): NewChannel<ChannelOfType<T>> {
+    const localChannelId = `blahblahblah`;
+    return { type, localChannelId };
+}
+
+const newTextChannel = makeNewChannel('text');
+// This should work
+newTextChannel.phoneNumber = '613-555-1234';
+
+const newTextChannel2 : NewChannel<TextChannel> = makeNewChannel('text');
+// Compare with this, which ofc works.
+newTextChannel2.phoneNumber = '613-555-1234';

tests/cases/conformance/types/keyof/keyofAndIndexedAccess.ts

@@ -33,7 +33,8 @@ type K03 = keyof boolean;  // "valueOf"
 type K04 = keyof void;  // never
 type K05 = keyof undefined;  // never
 type K06 = keyof null;  // never
-type K07 = keyof never;  // never
+type K07 = keyof never;  // string | number | symbol
+type K08 = keyof unknown; // never
 
 type K10 = keyof Shape;  // "name" | "width" | "height" | "visible"
 type K11 = keyof Shape[];  // "length" | "toString" | ...