👍 Add isRecordLike and isRecordLikeOf functions

Author: lambdalisue

is/__snapshots__/annotation_test.ts.snap

@@ -1,19 +1,19 @@
 export const snapshot = {};
 
-snapshot[`isOptionalOf<T> > returns properly named function 1`] = `"isOptionalOf(isNumber)"`;
-
-snapshot[`isOptionalOf<T> > returns properly named function 2`] = `"isOptionalOf(isNumber)"`;
-
 snapshot[`isUnwrapOptionalOf<T> > returns properly named function 1`] = `"isNumber"`;
 
 snapshot[`isUnwrapOptionalOf<T> > returns properly named function 2`] = `"isNumber"`;
 
 snapshot[`isUnwrapOptionalOf<T> > returns properly named function 3`] = `"isNumber"`;
 
+snapshot[`isReadonlyOf<T> > returns properly named function 1`] = `"isReadonlyOf(isNumber)"`;
+
+snapshot[`isReadonlyOf<T> > returns properly named function 2`] = `"isReadonlyOf(isReadonlyOf(isNumber))"`;
+
 snapshot[`isUnwrapReadonlyOf<T> > returns properly named function 1`] = `"isNumber"`;
 
 snapshot[`isUnwrapReadonlyOf<T> > returns properly named function 2`] = `"isReadonlyOf(isNumber)"`;
 
-snapshot[`isReadonlyOf<T> > returns properly named function 1`] = `"isReadonlyOf(isNumber)"`;
+snapshot[`isOptionalOf<T> > returns properly named function 1`] = `"isOptionalOf(isNumber)"`;
 
-snapshot[`isReadonlyOf<T> > returns properly named function 2`] = `"isReadonlyOf(isReadonlyOf(isNumber))"`;
+snapshot[`isOptionalOf<T> > returns properly named function 2`] = `"isOptionalOf(isNumber)"`;

is/__snapshots__/factory_test.ts.snap

@@ -1,52 +1,8 @@
 export const snapshot = {};
 
-snapshot[`isObjectOf<T> > returns properly named function 1`] = `
-"isObjectOf({
-  a: isNumber,
-  b: isString,
-  c: isBoolean
-})"
-`;
-
-snapshot[`isObjectOf<T> > returns properly named function 2`] = `"isObjectOf({a: a})"`;
-
-snapshot[`isObjectOf<T> > returns properly named function 3`] = `
-"isObjectOf({
-  a: isObjectOf({
-    b: isObjectOf({c: isBoolean})
-  })
-})"
-`;
-
-snapshot[`isArrayOf<T> > returns properly named function 1`] = `"isArrayOf(isNumber)"`;
-
-snapshot[`isArrayOf<T> > returns properly named function 2`] = `"isArrayOf((anonymous))"`;
-
-snapshot[`isReadonlyTupleOf<T> > returns properly named function 1`] = `
-"isReadonlyOf(isTupleOf([
-  isNumber,
-  isString,
-  isBoolean
-]))"
-`;
-
-snapshot[`isReadonlyTupleOf<T> > returns properly named function 2`] = `"isReadonlyOf(isTupleOf([(anonymous)]))"`;
-
-snapshot[`isReadonlyTupleOf<T> > returns properly named function 3`] = `
-"isReadonlyOf(isTupleOf([
-  isReadonlyOf(isTupleOf([
-    isReadonlyOf(isTupleOf([
-      isNumber,
-      isString,
-      isBoolean
-    ]))
-  ]))
-]))"
-`;
-
-snapshot[`isSetOf<T> > returns properly named function 1`] = `"isSetOf(isNumber)"`;
+snapshot[`isInstanceOf<T> > returns properly named function 1`] = `"isInstanceOf(Date)"`;
 
-snapshot[`isSetOf<T> > returns properly named function 2`] = `"isSetOf((anonymous))"`;
+snapshot[`isInstanceOf<T> > returns properly named function 2`] = `"isInstanceOf((anonymous))"`;
 
 snapshot[`isTupleOf<T> > returns properly named function 1`] = `
 "isTupleOf([
@@ -70,9 +26,17 @@ snapshot[`isTupleOf<T> > returns properly named function 3`] = `
 ])"
 `;
 
-snapshot[`isRecordOf<T> > returns properly named function 1`] = `"isRecordOf(isNumber, undefined)"`;
+snapshot[`isRecordLikeOf<T> > returns properly named function 1`] = `"isRecordLikeOf(isNumber, undefined)"`;
 
-snapshot[`isRecordOf<T> > returns properly named function 2`] = `"isRecordOf((anonymous), undefined)"`;
+snapshot[`isRecordLikeOf<T> > returns properly named function 2`] = `"isRecordLikeOf((anonymous), undefined)"`;
+
+snapshot[`isRecordLikeOf<T, K> > returns properly named function 1`] = `"isRecordLikeOf(isNumber, isString)"`;
+
+snapshot[`isRecordLikeOf<T, K> > returns properly named function 2`] = `"isRecordLikeOf((anonymous), isString)"`;
+
+snapshot[`isMapOf<T, K> > returns properly named function 1`] = `"isMapOf(isNumber, isString)"`;
+
+snapshot[`isMapOf<T, K> > returns properly named function 2`] = `"isMapOf((anonymous), isString)"`;
 
 snapshot[`isReadonlyTupleOf<T, E> > returns properly named function 1`] = `
 "isReadonlyOf(isTupleOf([
@@ -96,37 +60,31 @@ snapshot[`isReadonlyTupleOf<T, E> > returns properly named function 3`] = `
 ], isArray))"
 `;
 
-snapshot[`isTupleOf<T, E> > returns properly named function 1`] = `
-"isTupleOf([
-  isNumber,
-  isString,
-  isBoolean
-], isArray)"
-`;
+snapshot[`isMapOf<T> > returns properly named function 1`] = `"isMapOf(isNumber, undefined)"`;
 
-snapshot[`isTupleOf<T, E> > returns properly named function 2`] = `"isTupleOf([(anonymous)], isArrayOf(isString))"`;
+snapshot[`isMapOf<T> > returns properly named function 2`] = `"isMapOf((anonymous), undefined)"`;
 
-snapshot[`isTupleOf<T, E> > returns properly named function 3`] = `
-"isTupleOf([
-  isTupleOf([
-    isTupleOf([
-      isNumber,
-      isString,
-      isBoolean
-    ], isArray)
-  ], isArray)
-])"
+snapshot[`isObjectOf<T> > returns properly named function 1`] = `
+"isObjectOf({
+  a: isNumber,
+  b: isString,
+  c: isBoolean
+})"
 `;
 
-snapshot[`isInstanceOf<T> > returns properly named function 1`] = `"isInstanceOf(Date)"`;
-
-snapshot[`isInstanceOf<T> > returns properly named function 2`] = `"isInstanceOf((anonymous))"`;
+snapshot[`isObjectOf<T> > returns properly named function 2`] = `"isObjectOf({a: a})"`;
 
-snapshot[`isLiteralOneOf<T> > returns properly named function 1`] = `'isLiteralOneOf(["hello", "world"])'`;
+snapshot[`isObjectOf<T> > returns properly named function 3`] = `
+"isObjectOf({
+  a: isObjectOf({
+    b: isObjectOf({c: isBoolean})
+  })
+})"
+`;
 
-snapshot[`isMapOf<T> > returns properly named function 1`] = `"isMapOf(isNumber, undefined)"`;
+snapshot[`isRecordOf<T> > returns properly named function 1`] = `"isRecordOf(isNumber, undefined)"`;
 
-snapshot[`isMapOf<T> > returns properly named function 2`] = `"isMapOf((anonymous), undefined)"`;
+snapshot[`isRecordOf<T> > returns properly named function 2`] = `"isRecordOf((anonymous), undefined)"`;
 
 snapshot[`isStrictOf<T> > returns properly named function 1`] = `
 "isStrictOf(isObjectOf({
@@ -146,10 +104,6 @@ snapshot[`isStrictOf<T> > returns properly named function 3`] = `
 }))"
 `;
 
-snapshot[`isRecordOf<T, K> > returns properly named function 1`] = `"isRecordOf(isNumber, isString)"`;
-
-snapshot[`isRecordOf<T, K> > returns properly named function 2`] = `"isRecordOf((anonymous), isString)"`;
-
 snapshot[`isLiteralOf<T> > returns properly named function 1`] = `'isLiteralOf("hello")'`;
 
 snapshot[`isLiteralOf<T> > returns properly named function 2`] = `"isLiteralOf(100)"`;
@@ -164,18 +118,72 @@ snapshot[`isLiteralOf<T> > returns properly named function 6`] = `"isLiteralOf(u
 
 snapshot[`isLiteralOf<T> > returns properly named function 7`] = `"isLiteralOf(Symbol(asdf))"`;
 
-snapshot[`isMapOf<T, K> > returns properly named function 1`] = `"isMapOf(isNumber, isString)"`;
+snapshot[`isLiteralOneOf<T> > returns properly named function 1`] = `'isLiteralOneOf(["hello", "world"])'`;
 
-snapshot[`isMapOf<T, K> > returns properly named function 2`] = `"isMapOf((anonymous), isString)"`;
+snapshot[`isReadonlyTupleOf<T> > returns properly named function 1`] = `
+"isReadonlyOf(isTupleOf([
+  isNumber,
+  isString,
+  isBoolean
+]))"
+`;
+
+snapshot[`isReadonlyTupleOf<T> > returns properly named function 2`] = `"isReadonlyOf(isTupleOf([(anonymous)]))"`;
+
+snapshot[`isReadonlyTupleOf<T> > returns properly named function 3`] = `
+"isReadonlyOf(isTupleOf([
+  isReadonlyOf(isTupleOf([
+    isReadonlyOf(isTupleOf([
+      isNumber,
+      isString,
+      isBoolean
+    ]))
+  ]))
+]))"
+`;
+
+snapshot[`isReadonlyUniformTupleOf<T> > returns properly named function 1`] = `"isReadonlyOf(isUniformTupleOf(3, isAny))"`;
+
+snapshot[`isReadonlyUniformTupleOf<T> > returns properly named function 2`] = `"isReadonlyOf(isUniformTupleOf(3, isNumber))"`;
+
+snapshot[`isReadonlyUniformTupleOf<T> > returns properly named function 3`] = `"isReadonlyOf(isUniformTupleOf(3, (anonymous)))"`;
 
 snapshot[`isUniformTupleOf<T> > returns properly named function 1`] = `"isUniformTupleOf(3, isAny)"`;
 
 snapshot[`isUniformTupleOf<T> > returns properly named function 2`] = `"isUniformTupleOf(3, isNumber)"`;
 
 snapshot[`isUniformTupleOf<T> > returns properly named function 3`] = `"isUniformTupleOf(3, (anonymous))"`;
 
-snapshot[`isReadonlyUniformTupleOf<T> > returns properly named function 1`] = `"isReadonlyOf(isUniformTupleOf(3, isAny))"`;
+snapshot[`isRecordOf<T, K> > returns properly named function 1`] = `"isRecordOf(isNumber, isString)"`;
 
-snapshot[`isReadonlyUniformTupleOf<T> > returns properly named function 2`] = `"isReadonlyOf(isUniformTupleOf(3, isNumber))"`;
+snapshot[`isRecordOf<T, K> > returns properly named function 2`] = `"isRecordOf((anonymous), isString)"`;
 
-snapshot[`isReadonlyUniformTupleOf<T> > returns properly named function 3`] = `"isReadonlyOf(isUniformTupleOf(3, (anonymous)))"`;
+snapshot[`isArrayOf<T> > returns properly named function 1`] = `"isArrayOf(isNumber)"`;
+
+snapshot[`isArrayOf<T> > returns properly named function 2`] = `"isArrayOf((anonymous))"`;
+
+snapshot[`isTupleOf<T, E> > returns properly named function 1`] = `
+"isTupleOf([
+  isNumber,
+  isString,
+  isBoolean
+], isArray)"
+`;
+
+snapshot[`isTupleOf<T, E> > returns properly named function 2`] = `"isTupleOf([(anonymous)], isArrayOf(isString))"`;
+
+snapshot[`isTupleOf<T, E> > returns properly named function 3`] = `
+"isTupleOf([
+  isTupleOf([
+    isTupleOf([
+      isNumber,
+      isString,
+      isBoolean
+    ], isArray)
+  ], isArray)
+])"
+`;
+
+snapshot[`isSetOf<T> > returns properly named function 1`] = `"isSetOf(isNumber)"`;
+
+snapshot[`isSetOf<T> > returns properly named function 2`] = `"isSetOf((anonymous))"`;

is/__snapshots__/utility_test.ts.snap

@@ -1,22 +1,5 @@
 export const snapshot = {};
 
-snapshot[`isUnionOf<T> > returns properly named function 1`] = `
-"isUnionOf([
-  isNumber,
-  isString,
-  isBoolean
-])"
-`;
-
-snapshot[`isOmitOf<T, K> > returns properly named function 1`] = `
-"isObjectOf({
-  a: isNumber,
-  c: isBoolean
-})"
-`;
-
-snapshot[`isOmitOf<T, K> > returns properly named function 2`] = `"isObjectOf({a: isNumber})"`;
-
 snapshot[`isPartialOf<T> > returns properly named function 1`] = `
 "isObjectOf({
   a: isOptionalOf(isNumber),
@@ -39,15 +22,6 @@ snapshot[`isPartialOf<T> > returns properly named function 2`] = `
 })"
 `;
 
-snapshot[`isPickOf<T, K> > returns properly named function 1`] = `
-"isObjectOf({
-  a: isNumber,
-  c: isBoolean
-})"
-`;
-
-snapshot[`isPickOf<T, K> > returns properly named function 2`] = `"isObjectOf({a: isNumber})"`;
-
 snapshot[`isRequiredOf<T> > returns properly named function 1`] = `
 "isObjectOf({
   a: isNumber,
@@ -76,3 +50,29 @@ snapshot[`isIntersectionOf<T> > returns properly named function 1`] = `
   b: isString
 })"
 `;
+
+snapshot[`isPickOf<T, K> > returns properly named function 1`] = `
+"isObjectOf({
+  a: isNumber,
+  c: isBoolean
+})"
+`;
+
+snapshot[`isPickOf<T, K> > returns properly named function 2`] = `"isObjectOf({a: isNumber})"`;
+
+snapshot[`isOmitOf<T, K> > returns properly named function 1`] = `
+"isObjectOf({
+  a: isNumber,
+  c: isBoolean
+})"
+`;
+
+snapshot[`isOmitOf<T, K> > returns properly named function 2`] = `"isObjectOf({a: isNumber})"`;
+
+snapshot[`isUnionOf<T> > returns properly named function 1`] = `
+"isUnionOf([
+  isNumber,
+  isString,
+  isBoolean
+])"
+`;

is/core.ts

@@ -142,6 +142,9 @@ export function isSet(x: unknown): x is Set<unknown> {
 /**
  * Return `true` if the type of `x` is `Record<PropertyKey, unknown>`.
  *
+ * Note that this function check if the `x` is an instance of `Object`.
+ * Use `isRecordLike` instead if you want to check if the `x` satisfies the `Record<PropertyKey, unknown>` type.
+ *
  * ```ts
  * import { is } from "https://deno.land/x/unknownutil@$MODULE_VERSION/mod.ts";
  *
@@ -158,6 +161,33 @@ export function isRecord(
   return x != null && typeof x === "object" && x.constructor === Object;
 }
 
+/**
+ * Return `true` if the type of `x` is like `Record<PropertyKey, unknown>`.
+ *
+ * Note that this function returns `true` for ambiguous instances like `Set`, `Map`, `Date`, `Promise`, etc.
+ *
+ * ```ts
+ * import { is } from "https://deno.land/x/unknownutil@$MODULE_VERSION/mod.ts";
+ *
+ * const a: unknown = {"a": 0, "b": 1};
+ * if (is.RecordLike(a)) {
+ *   // a is narrowed to Record<PropertyKey, unknown>
+ *   const _: Record<PropertyKey, unknown> = a;
+ * }
+ *
+ * const b: unknown = new Date();
+ * if (is.RecordLike(b)) {
+ *   // a is narrowed to Record<PropertyKey, unknown>
+ *   const _: Record<PropertyKey, unknown> = b;
+ * }
+ * ```
+ */
+export function isRecordLike(
+  x: unknown,
+): x is Record<PropertyKey, unknown> {
+  return x != null && !Array.isArray(x) && typeof x === "object";
+}
+
 /**
  * Return `true` if the type of `x` is `Map<unknown, unknown>`.
  *
@@ -345,6 +375,7 @@ export default {
   Number: isNumber,
   Primitive: isPrimitive,
   Record: isRecord,
+  RecordLike: isRecordLike,
   Set: isSet,
   String: isString,
   Symbol: isSymbol,

is/core_test.ts

@@ -17,6 +17,7 @@ import is, {
   isNumber,
   isPrimitive,
   isRecord,
+  isRecordLike,
   isSet,
   isString,
   isSymbol,
@@ -147,6 +148,12 @@ Deno.test("isRecord", async (t) => {
   });
 });
 
+Deno.test("isRecordLike", async (t) => {
+  await testWithExamples(t, isRecordLike, {
+    validExamples: ["record", "date", "promise", "set", "map"],
+  });
+});
+
 Deno.test("isMap", async (t) => {
   await testWithExamples(t, isMap, {
     validExamples: ["map"],