@sinclair/typebox
Version:
Json Schema Type Builder with Static Type Resolution for TypeScript
172 lines (171 loc) • 6.25 kB
JavaScript
import { HasPropertyKey, IsStandardObject, IsArray, IsTypedArray, IsValueType } from '../guard/index.mjs';
import { ValuePointer } from '../pointer/index.mjs';
import { Clone } from '../clone/index.mjs';
import { Equal } from '../equal/equal.mjs';
import { TypeBoxError } from '../../type/error/index.mjs';
import { Literal } from '../../type/literal/index.mjs';
import { Object } from '../../type/object/index.mjs';
import { String } from '../../type/string/index.mjs';
import { Unknown } from '../../type/unknown/index.mjs';
import { Union } from '../../type/union/index.mjs';
export const Insert = Object({
type: Literal('insert'),
path: String(),
value: Unknown(),
});
export const Update = Object({
type: Literal('update'),
path: String(),
value: Unknown(),
});
export const Delete = Object({
type: Literal('delete'),
path: String(),
});
export const Edit = Union([Insert, Update, Delete]);
// ------------------------------------------------------------------
// Errors
// ------------------------------------------------------------------
export class ValueDiffError extends TypeBoxError {
constructor(value, message) {
super(message);
this.value = value;
}
}
// ------------------------------------------------------------------
// Command Factory
// ------------------------------------------------------------------
function CreateUpdate(path, value) {
return { type: 'update', path, value };
}
function CreateInsert(path, value) {
return { type: 'insert', path, value };
}
function CreateDelete(path) {
return { type: 'delete', path };
}
// ------------------------------------------------------------------
// AssertDiffable
// ------------------------------------------------------------------
function AssertDiffable(value) {
if (globalThis.Object.getOwnPropertySymbols(value).length > 0)
throw new ValueDiffError(value, 'Cannot diff objects with symbols');
}
// ------------------------------------------------------------------
// Diffing Generators
// ------------------------------------------------------------------
function* ObjectType(path, current, next) {
AssertDiffable(current);
AssertDiffable(next);
if (!IsStandardObject(next))
return yield CreateUpdate(path, next);
const currentKeys = globalThis.Object.getOwnPropertyNames(current);
const nextKeys = globalThis.Object.getOwnPropertyNames(next);
// ----------------------------------------------------------------
// inserts
// ----------------------------------------------------------------
for (const key of nextKeys) {
if (HasPropertyKey(current, key))
continue;
yield CreateInsert(`${path}/${key}`, next[key]);
}
// ----------------------------------------------------------------
// updates
// ----------------------------------------------------------------
for (const key of currentKeys) {
if (!HasPropertyKey(next, key))
continue;
if (Equal(current, next))
continue;
yield* Visit(`${path}/${key}`, current[key], next[key]);
}
// ----------------------------------------------------------------
// deletes
// ----------------------------------------------------------------
for (const key of currentKeys) {
if (HasPropertyKey(next, key))
continue;
yield CreateDelete(`${path}/${key}`);
}
}
function* ArrayType(path, current, next) {
if (!IsArray(next))
return yield CreateUpdate(path, next);
for (let i = 0; i < Math.min(current.length, next.length); i++) {
yield* Visit(`${path}/${i}`, current[i], next[i]);
}
for (let i = 0; i < next.length; i++) {
if (i < current.length)
continue;
yield CreateInsert(`${path}/${i}`, next[i]);
}
for (let i = current.length - 1; i >= 0; i--) {
if (i < next.length)
continue;
yield CreateDelete(`${path}/${i}`);
}
}
function* TypedArrayType(path, current, next) {
if (!IsTypedArray(next) || current.length !== next.length || globalThis.Object.getPrototypeOf(current).constructor.name !== globalThis.Object.getPrototypeOf(next).constructor.name)
return yield CreateUpdate(path, next);
for (let i = 0; i < Math.min(current.length, next.length); i++) {
yield* Visit(`${path}/${i}`, current[i], next[i]);
}
}
function* ValueType(path, current, next) {
if (current === next)
return;
yield CreateUpdate(path, next);
}
function* Visit(path, current, next) {
if (IsStandardObject(current))
return yield* ObjectType(path, current, next);
if (IsArray(current))
return yield* ArrayType(path, current, next);
if (IsTypedArray(current))
return yield* TypedArrayType(path, current, next);
if (IsValueType(current))
return yield* ValueType(path, current, next);
throw new ValueDiffError(current, 'Unable to diff value');
}
// ------------------------------------------------------------------
// Diff
// ------------------------------------------------------------------
export function Diff(current, next) {
return [...Visit('', current, next)];
}
// ------------------------------------------------------------------
// Patch
// ------------------------------------------------------------------
function IsRootUpdate(edits) {
return edits.length > 0 && edits[0].path === '' && edits[0].type === 'update';
}
function IsIdentity(edits) {
return edits.length === 0;
}
export function Patch(current, edits) {
if (IsRootUpdate(edits)) {
return Clone(edits[0].value);
}
if (IsIdentity(edits)) {
return Clone(current);
}
const clone = Clone(current);
for (const edit of edits) {
switch (edit.type) {
case 'insert': {
ValuePointer.Set(clone, edit.path, edit.value);
break;
}
case 'update': {
ValuePointer.Set(clone, edit.path, edit.value);
break;
}
case 'delete': {
ValuePointer.Delete(clone, edit.path);
break;
}
}
}
return clone;
}