first commit

node_modules/ob1/README.md

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+# ob1
+
+A small library for working with 0- and 1-based offsets in a type-checked way.

node_modules/ob1/package.json

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+{
+  "name": "ob1",
+  "version": "0.83.3",
+  "description": "A small library for working with 0- and 1-based offsets in a type-checked way.",
+  "main": "src/ob1.js",
+  "exports": {
+    ".": "./src/ob1.js",
+    "./package.json": "./package.json",
+    "./private/*": "./src/*.js"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git@github.com:facebook/metro.git"
+  },
+  "scripts": {
+    "prepare-release": "test -d build && rm -rf src.real && mv src src.real && mv build src",
+    "cleanup-release": "test ! -e build && mv src build && mv src.real src"
+  },
+  "keywords": [
+    "metro"
+  ],
+  "license": "MIT",
+  "dependencies": {
+    "flow-enums-runtime": "^0.0.6"
+  },
+  "engines": {
+    "node": ">=20.19.4"
+  }
+}

node_modules/ob1/src/__flowtests__/ob1-flowtest.js

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+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true,
+});
+exports.default = void 0;
+var _ob = require("../ob1");
+const FORTY_TWO_0 = (0, _ob.add0)(42);
+const FORTY_TWO_1 = (0, _ob.add1)(42);
+var _default = (exports.default = {
+  testSafeOps() {
+    (0, _ob.add)(FORTY_TWO_0, FORTY_TWO_0);
+    (0, _ob.add)(FORTY_TWO_0, FORTY_TWO_1);
+    (0, _ob.add)(FORTY_TWO_1, FORTY_TWO_0);
+    (0, _ob.sub)(FORTY_TWO_1, FORTY_TWO_1);
+    (0, _ob.add)(FORTY_TWO_0, 9000);
+    (0, _ob.add)(FORTY_TWO_0, 9000);
+    (0, _ob.add)(FORTY_TWO_1, 9000);
+    (0, _ob.sub)(FORTY_TWO_1, 9000);
+    (0, _ob.get0)(FORTY_TWO_0);
+    (0, _ob.get1)(FORTY_TWO_1);
+    (0, _ob.neg)(FORTY_TWO_0);
+    (0, _ob.add1)(FORTY_TWO_0);
+    (0, _ob.sub1)(FORTY_TWO_1);
+    (0, _ob.inc)(FORTY_TWO_0);
+    (0, _ob.inc)(FORTY_TWO_1);
+  },
+  testUnsafeOps() {
+    (0, _ob.add)(FORTY_TWO_1, FORTY_TWO_1);
+    (0, _ob.sub)(FORTY_TWO_0, FORTY_TWO_1);
+    FORTY_TWO_0 - 1;
+    FORTY_TWO_1 - 1;
+    (0, _ob.get0)(FORTY_TWO_1);
+    (0, _ob.get1)(FORTY_TWO_0);
+    (0, _ob.neg)(FORTY_TWO_1);
+    (0, _ob.add1)(FORTY_TWO_1);
+    (0, _ob.sub1)(FORTY_TWO_0);
+    (0, _ob.get0)(42);
+    (0, _ob.get1)(42);
+  },
+});

node_modules/ob1/src/__flowtests__/ob1-flowtest.js.flow

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+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ * @oncall react_native
+ */
+
+import type {Number0, Number1} from '../ob1';
+
+import {add, add0, add1, get0, get1, inc, neg, sub, sub1} from '../ob1';
+
+const FORTY_TWO_0 = add0(42);
+const FORTY_TWO_1 = add1(42);
+
+export default {
+  testSafeOps() {
+    (add(FORTY_TWO_0, FORTY_TWO_0): Number0);
+    (add(FORTY_TWO_0, FORTY_TWO_1): Number1);
+    (add(FORTY_TWO_1, FORTY_TWO_0): Number1);
+    (sub(FORTY_TWO_1, FORTY_TWO_1): Number0);
+    (add(FORTY_TWO_0, 9000): Number0);
+    (add(FORTY_TWO_0, 9000): Number0);
+    (add(FORTY_TWO_1, 9000): Number1);
+    (sub(FORTY_TWO_1, 9000): Number1);
+    (get0(FORTY_TWO_0): number);
+    (get1(FORTY_TWO_1): number);
+    (neg(FORTY_TWO_0): Number0);
+    (add1(FORTY_TWO_0): Number1);
+    (sub1(FORTY_TWO_1): Number0);
+    (inc(FORTY_TWO_0): Number0);
+    (inc(FORTY_TWO_1): Number1);
+  },
+  testUnsafeOps() {
+    // $FlowExpectedError[incompatible-type]  - adding two 1-based offsets.
+    add(FORTY_TWO_1, FORTY_TWO_1);
+
+    // $FlowExpectedError[incompatible-type]  - subtracting 1-based offset from 0-based offset.
+    sub(FORTY_TWO_0, FORTY_TWO_1);
+
+    // $FlowExpectedError[unsafe-arithmetic]  - direct computations with offsets are disallowed.
+    FORTY_TWO_0 - 1;
+
+    // $FlowExpectedError[unsafe-arithmetic]  - direct computations with offsets are disallowed.
+    FORTY_TWO_1 - 1;
+
+    // $FlowExpectedError[incompatible-type]  - extracting a 1-based offset as a 0-based number
+    get0(FORTY_TWO_1);
+
+    // $FlowExpectedError[incompatible-type]  - extracting a 0-based offset as a 1-based number
+    get1(FORTY_TWO_0);
+
+    // $FlowExpectedError[incompatible-type]  - negating a 1-based offset
+    neg(FORTY_TWO_1);
+
+    // $FlowExpectedError[incompatible-type]  - adding 1 to an offset that's already 1-based
+    add1(FORTY_TWO_1);
+
+    // $FlowExpectedError[incompatible-type]  - subtracting 1 from an offset that's already 0-based
+    sub1(FORTY_TWO_0);
+
+    // $FlowExpectedError[incompatible-type]  - extracting an arbitrary number as a 0-based number
+    get0(42);
+
+    // $FlowExpectedError[incompatible-type]  - extracting an arbitrary number as a 1-based number
+    get1(42);
+  },
+};

node_modules/ob1/src/ob1.d.ts

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+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ * @oncall react_native
+ */
+
+export declare type Number0 = symbol & {__Number0__: string};
+export declare type Number1 = symbol & {__Number1__: string};
+export declare function add(a: number, b: number): number;
+export declare function sub(a: number, b: number): number;
+export declare function get0(x: number): number;
+export declare function get1(x: number): number;
+export declare function add1(x: Number0 | number): Number1;
+export declare function sub1(x: Number1): Number0;
+export declare function neg(x: Number0): Number0;
+export declare function add0(x: number): Number0;
+export declare function inc(x: number): number;

node_modules/ob1/src/ob1.js

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+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true,
+});
+exports.add = add;
+exports.add0 = add0;
+exports.add1 = add1;
+exports.get0 = get0;
+exports.get1 = get1;
+exports.inc = inc;
+exports.neg = neg;
+exports.sub = sub;
+exports.sub1 = sub1;
+function add(a, b) {
+  return a + b;
+}
+function sub(a, b) {
+  return a - b;
+}
+function get0(x) {
+  return x;
+}
+function get1(x) {
+  return x;
+}
+function add1(x) {
+  return x + 1;
+}
+function sub1(x) {
+  return x - 1;
+}
+function neg(x) {
+  return -x;
+}
+function add0(x) {
+  return x;
+}
+function inc(x) {
+  return x + 1;
+}

node_modules/ob1/src/ob1.js.flow

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+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ * @oncall react_native
+ */
+
+/* eslint-disable no-redeclare */
+
+// A type representing 0-based offsets.
+export opaque type Number0 = number;
+// A type representing 1-based offsets.
+export opaque type Number1 = number;
+
+// Add two offsets or numbers.
+declare function add(a: Number1, b: number): Number1;
+declare function add(a: number, b: Number1): Number1;
+declare function add(a: Number0, b: number): Number0;
+declare function add(a: number, b: Number0): Number0;
+declare function add(a: Number1, b: Number0): Number1;
+declare function add(a: Number0, b: Number1): Number1;
+declare function add(a: Number0, b: Number0): Number0;
+
+export function add(a: number, b: number): number {
+  return a + b;
+}
+
+// Subtract a number or 0-based offset from a 1/0-based offset.
+declare function sub(a: Number1, b: number): Number1;
+declare function sub(a: Number0, b: number): Number0;
+declare function sub(a: number, b: Number0): Number0;
+declare function sub(a: Number0, b: number): Number0;
+declare function sub(a: Number1, b: Number0): Number1;
+declare function sub(a: Number0, b: Number0): Number0;
+declare function sub(a: Number1, b: Number1): Number0;
+
+export function sub(a: number, b: number): number {
+  return a - b;
+}
+
+// Get the underlying number of a 0-based offset, casting away the opaque type.
+declare function get0(x: Number0): number;
+declare function get0(x: void | null): void | null;
+export function get0(x: number): number {
+  return x;
+}
+
+// Get the underlying number of a 1-based offset, casting away the opaque type.
+declare function get1(x: Number1): number;
+declare function get1(x: void | null): void | null;
+export function get1(x: number): number {
+  return x;
+}
+
+// Add 1 to a 0-based offset, thus converting it to 1-based.
+export function add1(x: Number0 | number): Number1 {
+  return x + 1;
+}
+
+// Subtract 1 from a 1-based offset, thus converting it to 0-based.
+export function sub1(x: Number1): Number0 {
+  return x - 1;
+}
+
+// Negate a 0-based offset.
+export function neg(x: Number0): Number0 {
+  return -x;
+}
+
+// Cast a number to a 0-based offset.
+export function add0(x: number): Number0 {
+  return x;
+}
+
+// Increment a 0-based offset.
+declare function inc(a: Number0): Number0;
+// Increment a 1-based offset.
+declare function inc(a: Number1): Number1;
+
+export function inc(x: number): number {
+  return x + 1;
+}