Made a module focused on conversion

This commit is contained in:
Kir_Antipov 2023-01-24 11:56:32 +00:00
parent 9d7bf0f627
commit cc3f33cdb2
2 changed files with 1036 additions and 0 deletions

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src/utils/convert.ts Normal file
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import { stringEquals } from "@/utils/string-utils";
import { TypeOfResult, NamedType } from "@/utils/types/type-of";
import { $i } from "@/utils/collections/iterable";
import { getAllNames } from "@/utils/reflection/object-reflector";
/**
* Represents a function that converts a value to some target type.
*
* @template TInput - The input data type.
* @template UTarget - The target data type.
* @template ROutput - The output data type.
*/
export interface Converter<TInput = unknown, UTarget = unknown, ROutput = unknown> {
/**
* Converts a value to some target type.
*
* @param value - The value to convert.
* @param target - The target type of the conversion.
*
* @returns The converted value.
*/
(value: TInput, target: UTarget): ROutput;
}
/**
* Returns whether the given `obj` is `null`, `undefined`, or `NaN`.
*
* @param obj - The object to check.
*
* @returns `true` if the `obj` is `null`, `undefined`, or `NaN`; otherwise, `false`.
*/
function isInvalid(obj: unknown): boolean {
return obj === null || obj === undefined || typeof obj === "number" && isNaN(obj);
}
/**
* Always returns `undefined`, ignoring the input value.
*
* @param _obj - The input value to ignore.
*
* @returns `undefined`.
*/
export function toUndefined(_obj: unknown): undefined {
return undefined;
}
/**
* Converts the given `obj` to a string.
*
* @param obj - The object to convert.
*
* @returns The string representation of `obj`, or `undefined` if the input is `null`, `undefined`, or `NaN`.
*/
export function toString(obj: unknown): string {
return isInvalid(obj) ? undefined : String(obj);
}
/**
* Converts an input value to a boolean value.
*
* @param obj - The object to convert.
*
* @returns The converted boolean value, or `undefined` if the input value cannot be converted to boolean.
*/
export function toBoolean(obj: unknown): boolean {
if (isInvalid(obj)) {
return undefined;
}
switch (typeof obj) {
case "boolean":
return !!obj;
case "number":
return obj !== 0;
case "string":
if (stringEquals("true", obj, { ignoreCase: true })) {
return true;
}
if (stringEquals("false", obj, { ignoreCase: true })) {
return false;
}
break;
}
return undefined;
}
/**
* Converts an input value to a number type.
*
* @param obj - The input value to be converted.
* @param parser - A function to parse the input value.
*
* @returns The converted number value, or `undefined` if the input value cannot be converted to a number type.
*/
function toNumber(obj: unknown, parser: (value: string | number) => number): number {
if (isInvalid(obj)) {
return undefined;
}
switch (typeof obj) {
case "number":
return parser(obj);
case "boolean":
return obj ? 1 : 0;
case "string":
const parsedNumber = parser(obj);
return isNaN(parsedNumber) ? undefined : parsedNumber;
case "object":
if (obj instanceof Date && !isNaN(obj.getTime())) {
return obj.getTime();
}
break;
}
return undefined;
}
/**
* Converts an input value to an integer number.
*
* @param obj - The input value to be converted.
*
* @returns The converted integer number value, or `undefined` if the input value cannot be converted to an integer number type.
*/
export function toInteger(obj: unknown): number {
return toNumber(obj, parseInt);
}
/**
* Converts an input value to a floating-point number.
*
* @param obj - The input value to be converted.
*
* @returns The converted floating-point number value, or `undefined` if the input value cannot be converted to a floating-point number type.
*/
export function toFloat(obj: unknown): number {
return toNumber(obj, parseFloat);
}
/**
* Converts a value to a {@link Date}.
*
* @param obj - The value to convert.
*
* @returns The converted {@link Date}, or `undefined` if the value is invalid.
*/
export function toDate(obj: unknown): Date {
if (isInvalid(obj)) {
return undefined;
}
switch (typeof obj) {
case "object":
if (obj instanceof Date && !isNaN(obj.getTime())) {
return obj;
}
break;
case "string":
case "number":
const date = new Date(obj);
return isNaN(date.getTime()) ? undefined : date;
}
return undefined;
}
/**
* The regular expression used to parse a string representation of a regex into its pattern and flags parts.
*/
const REGEX_PARSER_REGEX = /\/(?<pattern>.*)\/(?<flags>[a-z]*)/;
/**
* Converts a value to a {@link RegExp}.
*
* @param obj - The value to convert.
*
* @returns A {@link RegExp} representing the given `obj`, or `undefined` if the input is invalid or cannot be converted to a regex.
*/
export function toRegExp(obj: unknown): RegExp | undefined {
if (obj instanceof RegExp) {
return obj;
}
if (typeof obj !== "string") {
return undefined;
}
const match = obj.match(REGEX_PARSER_REGEX);
if (!match) {
return undefined;
}
try {
return new RegExp(match.groups.pattern, match.groups.flags);
} catch {
return undefined;
}
}
/**
* A type alias for `globalThis`, the global object in a runtime environment.
*/
type GlobalThis = typeof globalThis;
/**
* A constructor function that creates instances of a given type.
*/
type Constructor<T> = new (...args: unknown[]) => T;
/**
* Represents the return type of a constructor function.
*
* @template T - The constructor function to extract the return type from.
*/
type ConstructorReturnType<T> = T extends Constructor<infer U> ? U : never;
/**
* Represents a member of the `globalThis` object that can be constructed.
*
* @template T - The name of the member of the `globalThis` object to check for constructibility.
*/
type ConstructibleGlobalThisMember<T extends keyof GlobalThis> = GlobalThis[T] extends Constructor<unknown> ? T : never;
/**
* The prefixes that indicate a method is a conversion method.
*/
const CONVERT_METHOD_PREFIXES = ["convert", "from"] as const;
/**
* A function that converts an unknown value to a typed value of a given type.
*/
type Convert<T> = (obj: unknown) => T;
/**
* Obtains the type of a method on a class or object that performs a conversion using a {@link Convert} function.
*/
type ConvertMethod<T> = {
[K in keyof T]: T[K] extends Convert<unknown>
? K extends `${typeof CONVERT_METHOD_PREFIXES[number]}${string}`
? T[K]
: never
: never;
}[keyof T];
/**
* A type that is convertible if it has at least one method that performs a conversion using a {@link Convert} function.
*/
type Convertible<T> = ConvertMethod<T> extends never ? never : T;
/**
* Represents a member of the `globalThis` object that is "convertible" based on whether it has at least one method that performs conversion using a {@link Convert} function.
*
* @template T - The name of the member of the `globalThis` object to check for convertibility.
*/
type ConvertibleGlobalThisMember<T extends keyof GlobalThis> = ConvertMethod<GlobalThis[T]> extends never ? never : T;
/**
* The prefixes that indicate a method is a parsing method.
*/
const PARSE_METHOD_PREFIXES = ["parse"] as const;
/**
* A function that parses a string and returns a value of a given type.
*/
type Parse<T> = (pattern: string) => T;
/**
* Obtains the type of a method on a class or object that performs parsing using a {@link Parse} function.
*/
type ParseMethod<T> = {
[K in keyof T]: T[K] extends Parse<unknown>
? K extends `${typeof PARSE_METHOD_PREFIXES[number]}${string}`
? T[K]
: never
: never;
}[keyof T];
/**
* Represents a type `T` which is considered "parsable" if it has at least one method that performs parsing using a {@link Parse} function.
*/
type Parsable<T> = ParseMethod<T> extends never ? never : T;
/**
* Represents a member of the `globalThis` object that is "parsable" based on whether it has at least one method that performs parsing using a {@link Parse} function.
*
* @template T - The name of the member of the `globalThis` object to check for parsability.
*/
type ParsableGlobalThisMember<T extends keyof GlobalThis> = ParseMethod<GlobalThis[T]> extends never ? never : T;
/**
* Retrieves a `Converter` function from the given object, if one is defined.
*
* @param obj - The object to retrieve the `Converter` function from.
* @returns A `Converter` function that can convert an unknown value to the target type `T`, or `undefined` if none was found.
*/
function getConverter<T>(obj: unknown): Convert<T> | undefined {
// Attempt to retrieve a `Converter` function from the object using the conversion method prefixes.
const converter = getParseLikeFunction(obj, CONVERT_METHOD_PREFIXES) as Convert<T>;
// If a `Converter` function was found, return it.
if (converter) {
return converter;
}
// Otherwise, attempt to retrieve a `Parser` function from the object and create a `Converter` function that uses it.
const parser = getParser<T>(obj);
if (parser) {
return x => typeof x === "string" ? parser(x) : undefined;
}
// If neither a `Converter` nor a `Parser` function was found, return undefined.
return undefined;
}
/**
* Retrieves a `Parser` function from the given object, if one is defined.
*
* @param obj - The object to retrieve the `Parser` function from.
* @returns A `Parser` function that can parse a string to the target type `T`, or `undefined` if none was found.
*/
function getParser<T>(obj: unknown): Parse<T> | undefined {
// Attempt to retrieve a `Parser` function from the object using the parsing method prefixes.
return getParseLikeFunction(obj, PARSE_METHOD_PREFIXES) as Parse<T>;
}
/**
* Attempts to retrieve a parsing method from the given object using the specified prefixes.
*
* @param obj - The object to retrieve the method from.
* @param prefixes - The list of method name prefixes to search for.
*
* @returns The first matching parse-like function that was found, or `undefined` if none were found.
*/
function getParseLikeFunction(obj: unknown, prefixes: readonly string[]): (obj: unknown) => unknown {
// If the object is invalid, return undefined.
if (isInvalid(obj)) {
return undefined;
}
// Find all method names on the object that start with one of the specified prefixes.
const propertyNames = getAllNames(obj);
const parseMethodNames = $i(propertyNames).filter(x => typeof obj[x] === "function" && prefixes.some(p => x.startsWith(p)));
// Determine the first parse-like method name by sorting them based on prefix precedence and taking the first result.
const firstParseMethodName = $i(parseMethodNames).min(
(a, b) => prefixes.findIndex(p => a.startsWith(p)) - prefixes.findIndex(p => b.startsWith(p))
);
// If no parse-like method names were found, return undefined.
if (!firstParseMethodName) {
return undefined;
}
// Return a function that invokes the first parse-like method with the specified input.
return x => obj[firstParseMethodName](x);
}
/**
* Map of known constructors and their corresponding converters.
*/
const KNOWN_CONSTRUCTORS = new Map<Constructor<unknown>, Convert<unknown>>([
[String, toString],
[Number, toFloat],
[Boolean, toBoolean],
[Date, toDate],
[RegExp, toRegExp],
]);
/**
* Map of known types and their corresponding converters.
*/
const KNOWN_TYPES = new Map<TypeOfResult, Convert<unknown>>([
["string", toString],
["number", toFloat],
["boolean", toBoolean],
["undefined", toUndefined],
]);
/**
* Converts a given object to the target type.
*
* @template T - The type of the returned value.
* @param obj - Value to be converted.
* @param type - Name of the type to convert the value to.
*
* @returns The converted value, or `undefined` if the conversion fails.
*/
export function toType<T extends TypeOfResult>(obj: unknown, type: T): NamedType<T>;
/**
* Converts a given object to the target type.
*
* @template T - A key of the `globalThis` object that represents the type to convert to, which must be a constructible type.
*
* @param obj - The unknown value to convert.
* @param type - The name of the constructor function corresponding to the target type `T`.
*
* @returns The converted value, or `undefined` if the conversion fails.
*/
export function toType<T extends keyof GlobalThis>(obj: unknown, type: T & ConstructibleGlobalThisMember<T>): ConstructorReturnType<GlobalThis[T]>;
/**
* Converts a given object to the target type.
*
* @template T - A key of the `globalThis` object that represents the type to convert to, which must have at least one method with a signature that matches the {@link ConvertMethod} type.
*
* @param obj - The unknown value to convert.
* @param type - The name of the convertible method corresponding to the target type `T`.
*
* @returns The converted value, or `undefined` if the conversion fails.
*/
export function toType<T extends keyof GlobalThis>(obj: unknown, type: T & ConvertibleGlobalThisMember<T>): ReturnType<ConvertMethod<GlobalThis[T]>>;
/**
* Parses the given string as the target type.
*
* @template T - A key of the `globalThis` object that represents the type to convert to, which must have at least one method with a signature that matches the {@link ParseMethod} type.
*
* @param obj - The string to parse and convert.
* @param type - The name of the parsing method corresponding to the target type `T`.
*
* @returns The parsed value, or `undefined` if the parsing fails.
*/
export function toType<T extends keyof GlobalThis>(obj: string, type: T & ParsableGlobalThisMember<T>): ReturnType<ParseMethod<GlobalThis[T]>>;
/**
* Converts a given object to the target type.
*
* @template T - The type of the returned value.
* @param obj - Value to be converted.
* @param convertible - Convertible type to convert the value to.
*
* @returns The converted value, or `undefined` if the conversion fails.
*/
export function toType<T>(obj: unknown, convertible: T & Convertible<T>): ReturnType<ConvertMethod<T>>;
/**
* Parses the given string as the target type.
*
* @template T - The type of the returned value.
* @param s - String to be parsed.
* @param parsable - Parsable type to convert the value to.
*
* @returns The parsed value, or `undefined` if the parsing fails.
*/
export function toType<T>(s: string, parsable: T & Parsable<T>): ReturnType<ParseMethod<T>>;
/**
* Converts a given object to the target type.
*
* @template T - The type of the returned value.
* @param obj - Value to be converted.
* @param constructor - Constructor of the type to convert the value to.
*
* @returns The converted value, or `undefined` if the conversion fails.
*/
export function toType<T>(obj: unknown, constructor: Constructor<T>): T;
/**
* A function that converts an unknown object to an unknown target type.
*
* @template T - The type to convert the value to.
* @param obj - The value to convert.
* @param target - The type or constructor function to use for the conversion.
*
* @returns The converted value of type `T`, or `undefined` if the conversion fails.
*/
export function toType<T = unknown>(obj: unknown, target: unknown): T;
/**
* Converts an object to the specified target type.
*
* @param obj - The object to convert.
* @param target - The target type to convert to.
*
* @returns An object of the specified target type, or `undefined` if the conversion failed.
*/
export function toType(obj: unknown, target: unknown): unknown {
// If the input object is invalid, return undefined.
if (isInvalid(obj)) {
return undefined;
}
if (typeof target === "string") {
// If the target is a string representing a known type, use the corresponding conversion function.
const knownConverter = KNOWN_TYPES.get(target as TypeOfResult);
if (knownConverter) {
return knownConverter(obj);
}
// If the target is a key of the `globalThis` object, convert the input to its type.
const globalThisMember = globalThis[target];
if (globalThisMember) {
return toType(obj, globalThisMember);
}
return undefined;
}
// If the target is a known constructor function, use its corresponding conversion function.
if (typeof target === "function" && KNOWN_CONSTRUCTORS.has(target as Constructor<unknown>)) {
const knownConverter = KNOWN_CONSTRUCTORS.get(target as Constructor<unknown>);
return knownConverter(obj);
}
try {
// Attempt to retrieve a converter function from the target type.
const converter = getConverter(target);
// If the converter function was found, use it to convert the input object.
if (converter !== undefined) {
const converted = converter(obj);
return isInvalid(converted) ? undefined : converted;
}
// If no converter function was found, assume that target is a constructor,
// since we've exhausted every over possibility.
return new (target as Constructor<unknown>)(obj);
} catch {
// If an error occurs during conversion, return undefined.
return undefined;
}
}

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import {
toUndefined,
toString,
toBoolean,
toInteger,
toFloat,
toDate,
toRegExp,
toType,
} from "@/utils/convert";
describe("toUndefined", () => {
test("always returns undefined", () => {
expect(toUndefined("something")).toBeUndefined();
expect(toUndefined(123)).toBeUndefined();
expect(toUndefined(null)).toBeUndefined();
expect(toUndefined(undefined)).toBeUndefined();
});
});
describe("toString", () => {
test("returns strings as is", () => {
expect(toString("test")).toBe("test");
});
test("converts valid values to strings", () => {
expect(toString(123)).toBe("123");
expect(toString(true)).toBe("true");
});
test("returns undefined for invalid values", () => {
expect(toString(null)).toBeUndefined();
expect(toString(undefined)).toBeUndefined();
expect(toString(NaN)).toBeUndefined();
});
});
describe("toBoolean", () => {
test("returns booleans as is", () => {
expect(toBoolean(false)).toBe(false);
expect(toBoolean(true)).toBe(true);
});
test("converts 'true' and 'false' strings to booleans ignoring their case", () => {
expect(toBoolean("true")).toBe(true);
expect(toBoolean("false")).toBe(false);
expect(toBoolean("TRUE")).toBe(true);
expect(toBoolean("FALSE")).toBe(false);
expect(toBoolean("True")).toBe(true);
expect(toBoolean("False")).toBe(false);
});
test("converts numbers to booleans", () => {
expect(toBoolean(0)).toBe(false);
expect(toBoolean(1)).toBe(true);
expect(toBoolean(2)).toBe(true);
});
test("returns undefined for invalid values", () => {
expect(toBoolean("invalid")).toBeUndefined();
expect(toBoolean(null)).toBeUndefined();
expect(toBoolean(undefined)).toBeUndefined();
expect(toBoolean(NaN)).toBeUndefined();
});
});
describe("toInteger", () => {
test("returns integers as is", () => {
expect(toInteger(-1)).toBe(-1);
expect(toInteger(0)).toBe(0);
expect(toInteger(123)).toBe(123);
});
test("converts floats to integers", () => {
expect(toInteger(123.456)).toBe(123);
expect(toInteger(true)).toBe(1);
expect(toInteger(false)).toBe(0);
});
test("converts dates to integers", () => {
const date = new Date();
expect(toInteger(date)).toBe(date.getTime());
});
test("converts valid strings to integers", () => {
expect(toInteger("-1")).toBe(-1);
expect(toInteger("-1.23")).toBe(-1);
expect(toInteger("123")).toBe(123);
expect(toInteger("123.456")).toBe(123);
});
test("converts booleans to integers", () => {
expect(toInteger(true)).toBe(1);
expect(toInteger(false)).toBe(0);
});
test("returns undefined for invalid values", () => {
expect(toInteger("invalid")).toBeUndefined();
expect(toInteger(null)).toBeUndefined();
expect(toInteger(undefined)).toBeUndefined();
expect(toInteger(NaN)).toBeUndefined();
});
});
describe("toFloat", () => {
test("returns numbers as is", () => {
expect(toFloat(-1)).toBe(-1);
expect(toFloat(0)).toBe(0);
expect(toFloat(123)).toBe(123);
expect(toFloat(123.456)).toBe(123.456);
});
test("converts dates to floats", () => {
const date = new Date();
expect(toFloat(date)).toBe(date.valueOf());
});
test("converts valid strings to floats", () => {
expect(toFloat("-1")).toBe(-1);
expect(toFloat("-1.23")).toBe(-1.23);
expect(toFloat("123")).toBe(123);
expect(toFloat("123.456")).toBe(123.456);
});
test("converts booleans to floats", () => {
expect(toFloat(true)).toBe(1);
expect(toFloat(false)).toBe(0);
});
test("returns undefined for invalid values", () => {
expect(toFloat("invalid")).toBeUndefined();
expect(toFloat(null)).toBeUndefined();
expect(toFloat(undefined)).toBeUndefined();
expect(toFloat(NaN)).toBeUndefined();
});
});
describe("toDate", () => {
test("returns dates as is", () => {
const date = new Date("1856-07-10T12:34:56.000Z");
expect(toDate(date)).toEqual(date);
});
test("converts valid values to Date objects", () => {
const date = new Date("1856-07-10T12:34:56.000Z");
expect(toDate(date.toISOString())).toEqual(date);
expect(toDate(date.getTime())).toEqual(date);
});
test("returns undefined for invalid values", () => {
expect(toDate(new Date("not a date"))).toBeUndefined();
expect(toDate("invalid")).toBeUndefined();
expect(toDate(null)).toBeUndefined();
expect(toDate(undefined)).toBeUndefined();
expect(toDate(NaN)).toBeUndefined();
});
});
describe("toRegExp", () => {
test("returns RegExps as is", () => {
const regex = /test/i;
expect(toRegExp(regex)).toEqual(regex);
});
test("converts valid string values to RegExp objects", () => {
const regex = /test/i;
expect(toRegExp(regex.toString())).toEqual(regex);
});
test("returns undefined for invalid values", () => {
expect(toDate("invalid")).toBeUndefined();
expect(toDate("/invalid")).toBeUndefined();
expect(toDate(null)).toBeUndefined();
expect(toDate(undefined)).toBeUndefined();
expect(toDate(NaN)).toBeUndefined();
});
});
describe("toType", () => {
describe("via 'typeof' type name", () => {
test("converts an object to a string", () => {
expect(toType("string", "string")).toBe("string");
expect(toType(123, "string")).toBe("123");
expect(toType(true, "string")).toBe("true");
expect(toType(false, "string")).toBe("false");
expect(toType(new Date("1856-07-10T12:34:56.000Z"), "string")).toBe(new Date("1856-07-10T12:34:56.000Z").toString());
expect(toType(/\d/, "string")).toBe(String(/\d/));
});
test("converts an object to a number", () => {
expect(toType(123, "number")).toBe(123);
expect(toType(123.456, "number")).toBe(123.456);
expect(toType("123", "number")).toBe(123);
expect(toType("123.456", "number")).toBe(123.456);
expect(toType(false, "number")).toBe(0);
expect(toType(true, "number")).toBe(1);
expect(toType(new Date("1856-07-10T12:34:56.000Z"), "number")).toBe(new Date("1856-07-10T12:34:56.000Z").getTime());
});
test("converts an object to a boolean", () => {
expect(toType(true, "boolean")).toBe(true);
expect(toType(false, "boolean")).toBe(false);
expect(toType(1, "boolean")).toBe(true);
expect(toType(0, "boolean")).toBe(false);
expect(toType(123.456, "boolean")).toBe(true);
expect(toType("true", "boolean")).toBe(true);
expect(toType("false", "boolean")).toBe(false);
expect(toType("TRUE", "boolean")).toBe(true);
expect(toType("FALSE", "boolean")).toBe(false);
expect(toType("True", "boolean")).toBe(true);
expect(toType("False", "boolean")).toBe(false);
});
test("converts an object to undefined", () => {
expect(toType(true, "undefined")).toBeUndefined();
expect(toType(false, "undefined")).toBeUndefined();
expect(toType("string", "undefined")).toBeUndefined();
expect(toType({}, "undefined")).toBeUndefined();
expect(toType(0, "undefined")).toBeUndefined();
expect(toType(1, "undefined")).toBeUndefined();
expect(toType(new Date(), "undefined")).toBeUndefined();
expect(toType(/\d/, "undefined")).toBeUndefined();
});
test("returns undefined when conversion is not possible", () => {
expect(toType(undefined, "string")).toBeUndefined();
expect(toType(undefined, "number")).toBeUndefined();
expect(toType(undefined, "boolean")).toBeUndefined();
expect(toType(null, "string")).toBeUndefined();
expect(toType(null, "number")).toBeUndefined();
expect(toType(null, "boolean")).toBeUndefined();
expect(toType(NaN, "string")).toBeUndefined();
expect(toType(NaN, "number")).toBeUndefined();
expect(toType(NaN, "boolean")).toBeUndefined();
expect(toType("abc", "number")).toBeUndefined();
expect(toType("abc", "boolean")).toBeUndefined();
expect(toType("123", "date")).toBeUndefined();
expect(toType("123", "void")).toBeUndefined();
});
});
describe("via constructor", () => {
test("converts an object to a string", () => {
expect(toType("string", String)).toBe("string");
expect(toType(123, String)).toBe("123");
expect(toType(true, String)).toBe("true");
expect(toType(false, String)).toBe("false");
expect(toType(new Date("1856-07-10T12:34:56.000Z"), String)).toBe(new Date("1856-07-10T12:34:56.000Z").toString());
expect(toType(/\d/, String)).toBe(String(/\d/));
});
test("converts an object to a number", () => {
expect(toType(123, Number)).toBe(123);
expect(toType(123.456, Number)).toBe(123.456);
expect(toType("123", Number)).toBe(123);
expect(toType("123.456", Number)).toBe(123.456);
expect(toType(false, Number)).toBe(0);
expect(toType(true, Number)).toBe(1);
expect(toType(new Date("1856-07-10T12:34:56.000Z"), Number)).toBe(new Date("1856-07-10T12:34:56.000Z").getTime());
});
test("converts an object to a boolean", () => {
expect(toType(true, Boolean)).toBe(true);
expect(toType(false, Boolean)).toBe(false);
expect(toType(1, Boolean)).toBe(true);
expect(toType(0, Boolean)).toBe(false);
expect(toType(123.456, Boolean)).toBe(true);
expect(toType("true", Boolean)).toBe(true);
expect(toType("false", Boolean)).toBe(false);
expect(toType("TRUE", Boolean)).toBe(true);
expect(toType("FALSE", Boolean)).toBe(false);
expect(toType("True", Boolean)).toBe(true);
expect(toType("False", Boolean)).toBe(false);
});
test("converts an object to a Date", () => {
const date = new Date("1856-07-10T12:34:56.000Z");
expect(toType(date, Date)).toEqual(date);
expect(toType(date.toISOString(), Date)).toEqual(date);
expect(toType(date.getTime(), Date)).toEqual(date);
});
test("converts an object to a RegExp", () => {
const regex = /^a+$/im;
expect(toType(regex, RegExp)).toEqual(regex);
expect(toType(String(regex), RegExp)).toEqual(regex);
});
test("returns undefined when conversion is not possible", () => {
expect(toType(undefined, String)).toBeUndefined();
expect(toType(undefined, Number)).toBeUndefined();
expect(toType(undefined, Boolean)).toBeUndefined();
expect(toType(undefined, Date)).toBeUndefined();
expect(toType(undefined, RegExp)).toBeUndefined();
expect(toType(null, String)).toBeUndefined();
expect(toType(null, Number)).toBeUndefined();
expect(toType(null, Boolean)).toBeUndefined();
expect(toType(null, Date)).toBeUndefined();
expect(toType(null, RegExp)).toBeUndefined();
expect(toType(NaN, String)).toBeUndefined();
expect(toType(NaN, Number)).toBeUndefined();
expect(toType(NaN, Boolean)).toBeUndefined();
expect(toType(NaN, Date)).toBeUndefined();
expect(toType(NaN, RegExp)).toBeUndefined();
expect(toType("abc", Number)).toBeUndefined();
expect(toType("abc", Boolean)).toBeUndefined();
expect(toType("abc", Date)).toBeUndefined();
expect(toType("123", RegExp)).toBeUndefined();
expect(toType("123", undefined)).toBeUndefined();
});
});
describe("via globalThis type name", () => {
test("converts an object to a string", () => {
expect(toType("string", "String")).toBe("string");
expect(toType(123, "String")).toBe("123");
expect(toType(true, "String")).toBe("true");
expect(toType(false, "String")).toBe("false");
expect(toType(new Date("1856-07-10T12:34:56.000Z"), "String")).toBe(new Date("1856-07-10T12:34:56.000Z").toString());
expect(toType(/\d/, "String")).toBe(String(/\d/));
});
test("converts an object to a number", () => {
expect(toType(123, "Number")).toBe(123);
expect(toType(123.456, "Number")).toBe(123.456);
expect(toType("123", "Number")).toBe(123);
expect(toType("123.456", "Number")).toBe(123.456);
expect(toType(false, "Number")).toBe(0);
expect(toType(true, "Number")).toBe(1);
expect(toType(new Date("1856-07-10T12:34:56.000Z"), "Number")).toBe(new Date("1856-07-10T12:34:56.000Z").getTime());
});
test("converts an object to a boolean", () => {
expect(toType(true, "Boolean")).toBe(true);
expect(toType(false, "Boolean")).toBe(false);
expect(toType(1, "Boolean")).toBe(true);
expect(toType(0, "Boolean")).toBe(false);
expect(toType(123.456, "Boolean")).toBe(true);
expect(toType("true", "Boolean")).toBe(true);
expect(toType("false", "Boolean")).toBe(false);
expect(toType("TRUE", "Boolean")).toBe(true);
expect(toType("FALSE", "Boolean")).toBe(false);
expect(toType("True", "Boolean")).toBe(true);
expect(toType("False", "Boolean")).toBe(false);
});
test("converts an object to a Date", () => {
const date = new Date("1856-07-10T12:34:56.000Z");
expect(toType(date, "Date")).toEqual(date);
expect(toType(date.toISOString(), "Date")).toEqual(date);
expect(toType(date.getTime(), "Date")).toEqual(date);
});
test("converts an object to a RegExp", () => {
const regex = /^a+$/im;
expect(toType(regex, "RegExp")).toEqual(regex);
expect(toType(String(regex), "RegExp")).toEqual(regex);
});
test("returns undefined when conversion is not possible", () => {
expect(toType(undefined, "String")).toBeUndefined();
expect(toType(undefined, "Number")).toBeUndefined();
expect(toType(undefined, "Boolean")).toBeUndefined();
expect(toType(undefined, "Date")).toBeUndefined();
expect(toType(undefined, "RegExp")).toBeUndefined();
expect(toType(null, "String")).toBeUndefined();
expect(toType(null, "Number")).toBeUndefined();
expect(toType(null, "Boolean")).toBeUndefined();
expect(toType(null, "Date")).toBeUndefined();
expect(toType(null, "RegExp")).toBeUndefined();
expect(toType(NaN, "String")).toBeUndefined();
expect(toType(NaN, "Number")).toBeUndefined();
expect(toType(NaN, "Boolean")).toBeUndefined();
expect(toType(NaN, "Date")).toBeUndefined();
expect(toType(NaN, "RegExp")).toBeUndefined();
expect(toType("abc", "Number")).toBeUndefined();
expect(toType("abc", "Boolean")).toBeUndefined();
expect(toType("abc", "Date")).toBeUndefined();
expect(toType("123", "RegExp")).toBeUndefined();
expect(toType("123", "NotAType")).toBeUndefined();
});
});
describe("from convertible object", () => {
test("converts a value via the standard 'convert' function", () => {
const convertible = {
convert: jest.fn().mockImplementation(o => String(o)),
};
expect(toType(123, convertible)).toBe("123");
expect(convertible.convert).toBeCalledTimes(1);
expect(convertible.convert).toBeCalledWith(123);
});
test("converts a value via a first function that start with 'convert'", () => {
const convertible = {
convertObjectToNumber: jest.fn().mockImplementation(o => String(o)),
};
expect(toType(123, convertible)).toBe("123");
expect(convertible.convertObjectToNumber).toBeCalledTimes(1);
expect(convertible.convertObjectToNumber).toBeCalledWith(123);
});
test("returns undefined when conversion is not possible", () => {
expect(toType(123, {})).toBeUndefined();
expect(toType(123, { notConvertFunction: () => 42 })).toBeUndefined();
});
test("returns undefined instead of throwing", () => {
const throwingConvertible = {
convert: jest.fn().mockImplementation(() => {
throw new Error("Conversion is impossible");
}),
};
const anotherThrowingConvertible = {
convertNothing: jest.fn().mockImplementation(() => {
throw new Error("Conversion is impossible");
}),
};
expect(toType(123, throwingConvertible)).toBeUndefined();
expect(throwingConvertible.convert).toHaveBeenCalledTimes(1);
expect(throwingConvertible.convert).toHaveBeenCalledWith(123);
expect(toType(123, anotherThrowingConvertible)).toBeUndefined();
expect(anotherThrowingConvertible.convertNothing).toHaveBeenCalledTimes(1);
expect(anotherThrowingConvertible.convertNothing).toHaveBeenCalledWith(123);
});
});
describe("from parsable object", () => {
test("parses a value via the standard 'parse' function", () => {
const parsable = {
parse: jest.fn().mockImplementation(s => +s),
};
expect(toType("123", parsable)).toBe(123);
expect(parsable.parse).toBeCalledTimes(1);
expect(parsable.parse).toBeCalledWith("123");
});
test("parses a value via a first function that start with 'parse'", () => {
const parsable = {
parseStringToNumber: jest.fn().mockImplementation(s => +s),
};
expect(toType("123", parsable)).toBe(123);
expect(parsable.parseStringToNumber).toBeCalledTimes(1);
expect(parsable.parseStringToNumber).toBeCalledWith("123");
});
test("returns undefined when the input value is not a string", () => {
const parsable = {
parse: jest.fn().mockImplementation(s => +s),
};
const anotherParsable = {
parseStringToNumber: jest.fn().mockImplementation(s => +s),
};
expect(toType(123, parsable)).toBeUndefined();
expect(parsable.parse).not.toBeCalled();
expect(toType(123, anotherParsable)).toBeUndefined();
expect(anotherParsable.parseStringToNumber).not.toBeCalled();
});
test("returns undefined when conversion is not possible", () => {
expect(toType("123", {})).toBeUndefined();
expect(toType("123", { notParseFunction: () => 42 })).toBeUndefined();
});
test("returns undefined instead of throwing", () => {
const throwingParsable = {
parse: jest.fn().mockImplementation(() => {
throw new Error("Parsing is impossible");
}),
};
const anotherThrowingParsable = {
parseNothing: jest.fn().mockImplementation(() => {
throw new Error("Parsing is impossible");
}),
};
expect(toType("123", throwingParsable)).toBeUndefined();
expect(throwingParsable.parse).toHaveBeenCalledTimes(1);
expect(throwingParsable.parse).toHaveBeenCalledWith("123");
expect(toType("123", anotherThrowingParsable)).toBeUndefined();
expect(anotherThrowingParsable.parseNothing).toHaveBeenCalledTimes(1);
expect(anotherThrowingParsable.parseNothing).toHaveBeenCalledWith("123");
});
});
});