test: jest (#26)

Q&A.ts

@@ -0,0 +1,150 @@
+/**
+ * 1. 泛型无默认值有字段提示,提升全
+ */
+function foo<T extends Partial<{ str: string; num: number; bool: boolean }>>(obj: T) {
+  obj;
+}
+
+foo({
+  str: "str",
+  // 键入n有字段提示num
+});
+
+/**
+ * 2. 泛型有默认值,只有首key类型提示
+ */
+function foo1<T extends Partial<{ str: string; num: number; bool: boolean }> = {}>(obj: T) {
+  obj;
+}
+
+foo1({
+  bool: false, // 首key,有字段提示,即输入b,提示bool
+  // 键入n无字段提示num
+});
+
+type Options<TComputed, ComputedReturnType> = {
+  computed: TComputed & ThisType<{ data: ComputedReturnType }>;
+};
+
+/**
+ * 3. 泛型字段为`Record<string, () => void>`时,若要通过this相互间引用,需要加默认值。
+ */
+function foo2<
+  TComputed extends Record<string, () => void> = {},
+  ComputedReturnType extends object = { [k in keyof TComputed]: ReturnType<TComputed[k]> },
+>(
+  obj: Options<TComputed, ComputedReturnType>,
+): ComputedReturnType {
+  obj;
+
+  return {} as any;
+}
+
+foo2({
+  computed: {
+    str() {
+      return "a";
+    },
+    bool() {
+      return this.data.str;
+    },
+  },
+});
+
+type Obj = {
+  str: string;
+  num: number;
+  literalNum: 123;
+};
+
+/**
+ * 4. 接上 TComputed约束有具体字段时,返回字面量需要加上const才可以(如num),且没有第二字段提示,且不可以相互this引用。
+ */
+function foo3<
+  TComputed extends { [k in keyof Obj]?: () => Obj[k] } = {},
+  // @ts-ignore 忽略ReturnType<TComputed[k]>报错
+  ComputedReturnType extends object = { [k in keyof TComputed]: ReturnType<TComputed[k]> },
+>(
+  obj: Options<TComputed, ComputedReturnType>,
+): ComputedReturnType {
+  obj;
+
+  return {} as any;
+}
+
+foo3({
+  computed: {
+    str() {
+      return "b";
+    },
+    literalNum() {
+      return 123 as const; // 需要加const
+    },
+    _aaa_other() { // 任意字段可以引用存在字段。
+      return this.data.str;
+    },
+    num() {
+      return 123;
+    },
+  },
+});
+
+foo3({
+  computed: {
+    _aaa_other() {
+      return 123;
+    },
+    // @ts-expect-error 存在字段不可以引用其他字段
+    num() {
+      // @ts-expect-error 存在字段不可以引用其他字段
+      return this.data._aaa_other;
+    },
+  },
+});
+
+// type Validator<TComputed, TObj, > = { [k in keyof TComputed as ReturnType<TComputed[k]> extends TObj[k]?never:k]:()=> TObj[k]};
+
+// type Option<TComputed, ComputedReturnType, TObj> = {
+//   computed?:
+//     & TComputed
+//     & ThisType<{ data: ComputedReturnType }>
+//     & Validator< TComputed, TObj>;
+// };
+
+// //
+// function foo4<
+//   TComputed extends Record<string, () => any> = {},
+//   // @ts-ignore 忽略ReturnType<TComputed[k]>报错
+//   ComputedReturnType extends object = { [k in keyof TComputed]: ReturnType<TComputed[k]> },
+// >(
+//   obj: Option<TComputed, ComputedReturnType, Obj>,
+// ): ComputedReturnType {
+//   obj;
+
+//   return {} as any;
+// }
+
+// const aaa = foo4({
+//   computed: {
+//     num() {
+//       return 123;
+//     },
+//     str() {
+//       return 123;
+//     },
+
+//   },
+// });
+
+// RootComponent({
+//   properties: {
+//     aaa: {
+//       type: String,
+//       value: 123,
+//     },
+//     bbb: {
+//       type: Number,
+//       value: "123",
+//     },
+//   },
+// });