Initial implementation, tests, readme

ljharb · ljharb · commit 6ec8c340c2ac · 2025-03-04T16:43:38.000-08:00
diff --git a/.eslintrc b/.eslintrc
@@ -0,0 +1,49 @@
+{
+	"root": true,
+
+	"extends": "@ljharb",
+
+	"globals": {
+		"Float16Array": false,
+		"Float32Array": false,
+		"Float64Array": false,
+		"Int16Array": false,
+		"Int32Array": false,
+		"Int8Array": false,
+		"Uint16Array": false,
+		"Uint32Array": false,
+		"Uint8Array": false,
+		"Uint8ClampedArray": false,
+		"BigInt64Array": false,
+		"BigUint64Array": false,
+	},
+
+	"rules": {
+		"func-style": 0,
+		"id-length": 0,
+		"new-cap": [2, {
+			"capIsNewExceptions": [
+				"Get",
+				"ToIntegerOrInfinity",
+				"ToString",
+				"TypedArrayLength",
+				"ValidateTypedArray",
+			],
+		}],
+		"no-magic-numbers": 0,
+	},
+
+	"overrides": [
+		{
+			"files": "test/**",
+			"rules": {
+				"max-len": 0,
+				"new-cap": [2, {
+					"capIsNewExceptions": [
+						"Z",
+					],
+				}],
+			},
+		},
+	],
+}
diff --git a/.github/FUNDING.yml b/.github/FUNDING.yml
@@ -0,0 +1,12 @@
+# These are supported funding model platforms
+
+github: [ljharb]
+patreon: # Replace with a single Patreon username
+open_collective: # Replace with a single Open Collective username
+ko_fi: # Replace with a single Ko-fi username
+tidelift: npm/typedarray.prototype.at
+community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+liberapay: # Replace with a single Liberapay username
+issuehunt: # Replace with a single IssueHunt username
+otechie: # Replace with a single Otechie username
+custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']
diff --git a/.github/workflows/node-aught.yml b/.github/workflows/node-aught.yml
@@ -0,0 +1,18 @@
+name: 'Tests: node.js < 10'
+
+on: [pull_request, push]
+
+jobs:
+  tests:
+    uses: ljharb/actions/.github/workflows/node.yml@main
+    with:
+      range: '< 10'
+      type: minors
+      command: npm run tests-only
+
+  node:
+    name: 'node < 10'
+    needs: [tests]
+    runs-on: ubuntu-latest
+    steps:
+      - run: 'echo tests completed'
diff --git a/.github/workflows/node-pretest.yml b/.github/workflows/node-pretest.yml
@@ -0,0 +1,7 @@
+name: 'Tests: pretest/posttest'
+
+on: [pull_request, push]
+
+jobs:
+  tests:
+    uses: ljharb/actions/.github/workflows/pretest.yml@main
diff --git a/.github/workflows/node-tens.yml b/.github/workflows/node-tens.yml
@@ -0,0 +1,21 @@
+name: 'Tests: node.js 10 - 20'
+
+on: [pull_request, push]
+
+permissions:
+  contents: read
+
+jobs:
+  tests:
+    uses: ljharb/actions/.github/workflows/node.yml@main
+    with:
+      range: '>= 10 < 20'
+      type: minors
+      command: npm run tests-only
+
+  node:
+    name: 'node 10 - 20'
+    needs: [tests]
+    runs-on: ubuntu-latest
+    steps:
+      - run: true
diff --git a/.github/workflows/node-twenties.yml b/.github/workflows/node-twenties.yml
@@ -0,0 +1,21 @@
+name: 'Tests: node.js >= 20'
+
+on: [pull_request, push]
+
+permissions:
+  contents: read
+
+jobs:
+  tests:
+    uses: ljharb/actions/.github/workflows/node.yml@main
+    with:
+      range: '>= 20'
+      type: minors
+      command: npm run tests-only
+
+  node:
+    name: 'node >= 20'
+    needs: [tests]
+    runs-on: ubuntu-latest
+    steps:
+      - run: true
diff --git a/.github/workflows/rebase.yml b/.github/workflows/rebase.yml
@@ -0,0 +1,9 @@
+name: Automatic Rebase
+
+on: [pull_request_target]
+
+jobs:
+  _:
+    uses: ljharb/actions/.github/workflows/rebase.yml@main
+    secrets:
+      token: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/require-allow-edits.yml b/.github/workflows/require-allow-edits.yml
@@ -0,0 +1,12 @@
+name: Require “Allow Edits”
+
+on: [pull_request_target]
+
+jobs:
+  _:
+    name: "Require “Allow Edits”"
+
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: ljharb/require-allow-edits@main
diff --git a/.gitignore b/.gitignore
@@ -133,3 +133,5 @@ dist
 npm-shrinkwrap.json
 package-lock.json
 yarn.lock
+
+.npmignore
diff --git a/.npmrc b/.npmrc
@@ -1 +1,3 @@
 package-lock=false
+allow-same-version=true
+message=v%s
diff --git a/.nycrc b/.nycrc
@@ -0,0 +1,9 @@
+{
+	"all": true,
+	"check-coverage": false,
+	"reporter": ["text-summary", "text", "html", "json"],
+	"exclude": [
+		"coverage",
+		"test"
+	]
+}
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -0,0 +1,6 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
diff --git a/README.md b/README.md
@@ -1,2 +1,74 @@
-# TypedArray.prototype.at
-An ES5 spec-compliant `TypedArray.prototype.at` shim/polyfill/replacement that works as far down as ES3
+# typedarray.prototype.at <sup>[![Version Badge][npm-version-svg]][package-url]</sup>
+
+[![github actions][actions-image]][actions-url]
+[![coverage][codecov-image]][codecov-url]
+[![License][license-image]][license-url]
+[![Downloads][downloads-image]][downloads-url]
+
+[![npm badge][npm-badge-png]][package-url]
+
+An ES spec-compliant `%TypedArray%.prototype.at` shim/polyfill/replacement that works as far down as ES3.
+
+This package implements the [es-shim API](https://github.com/es-shims/api) interface. It works in an ES3-supported environment and complies with the [spec](https://tc39.es/ecma262/#sec-%typedarray%.prototype.at).
+
+Because `%TypedArray%.prototype.at` depends on a receiver (the “this” value), the main export takes the typed array to operate on as the first argument.
+
+## Example
+
+```js
+var at = require('typedarray.prototype.at');
+var assert = require('assert');
+
+var ta = new Uint8Array([1, 2, 3]);
+
+assert.equal(at(ta, 0), 1);
+assert.equal(at(ta, 1), 2);
+assert.equal(at(ta, 2), 3);
+assert.equal(at(ta, -1), 3);
+assert.equal(at(ta, -2), 2);
+assert.equal(at(ta, -3), 1);
+```
+
+```js
+var shim = require('typedarray.prototype.at/shim');
+var getPolyfill = require('typedarray.prototype.at/polyfill');
+var assert = require('assert');
+/* when TypedArray#at is not present */
+delete Object.getPrototypeOf(Uint8Array.prototype).at;
+var shimmed = shim();
+assert.equal(shimmed, getPolyfill());
+assert.equal(shimmed, Uint8Array.prototype.at);
+
+var ta = new Uint8Array([1, 2, 3]);
+assert.equal(ta.at(-1), at(ta, -1));
+```
+
+```js
+var shim = require('typedarray.prototype.at/shim');
+var assert = require('assert');
+/* when TypedArray#at is present */
+var shimmed = shim();
+assert.equal(shimmed, Uint8Array.prototype.at);
+
+var ta = new Uint8Array([1, 2, 3]);
+assert.equal(ta.at(-1), at(ta, -1));
+```
+
+## Tests
+Simply clone the repo, `npm install`, and run `npm test`
+
+[package-url]: https://npmjs.org/package/typedarray.prototype.at
+[npm-version-svg]: https://versionbadg.es/es-shims/TypedArray.prototype.at.svg
+[deps-svg]: https://david-dm.org/es-shims/TypedArray.prototype.at.svg
+[deps-url]: https://david-dm.org/es-shims/TypedArray.prototype.at
+[dev-deps-svg]: https://david-dm.org/es-shims/TypedArray.prototype.at/dev-status.svg
+[dev-deps-url]: https://david-dm.org/es-shims/TypedArray.prototype.at#info=devDependencies
+[npm-badge-png]: https://nodei.co/npm/typedarray.prototype.at.png?downloads=true&stars=true
+[license-image]: https://img.shields.io/npm/l/typedarray.prototype.at.svg
+[license-url]: LICENSE
+[downloads-image]: https://img.shields.io/npm/dm/typedarray.prototype.at.svg
+[downloads-url]: https://npm-stat.com/charts.html?package=typedarray.prototype.at
+[codecov-image]: https://codecov.io/gh/es-shims/TypedArray.prototype.at/branch/main/graphs/badge.svg
+[codecov-url]: https://app.codecov.io/gh/es-shims/TypedArray.prototype.at/
+[actions-image]: https://img.shields.io/endpoint?url=https://github-actions-badge-u3jn4tfpocch.runkit.sh/es-shims/TypedArray.prototype.at
+[actions-url]: https://github.com/es-shims/TypedArray.prototype.at/actions
diff --git a/auto.js b/auto.js
@@ -0,0 +1,3 @@
+'use strict';
+
+require('./shim')();
diff --git a/implementation.js b/implementation.js
@@ -0,0 +1,25 @@
+'use strict';
+
+var Get = require('es-abstract/2024/Get');
+var ToIntegerOrInfinity = require('es-abstract/2024/ToIntegerOrInfinity');
+var ToString = require('es-abstract/2024/ToString');
+var TypedArrayLength = require('es-abstract/2024/TypedArrayLength');
+var ValidateTypedArray = require('es-abstract/2024/ValidateTypedArray');
+
+module.exports = function at(index) {
+	var O = this; // step 1
+
+	var taRecord = ValidateTypedArray(O, 'SEQ-CST'); // step 2
+
+	var len = TypedArrayLength(taRecord); // step 3
+
+	var relativeIndex = ToIntegerOrInfinity(index); // step 4
+
+	var k = relativeIndex >= 0 ? relativeIndex : len + relativeIndex; // step 5-6
+
+	if (k < 0 || k >= len) {
+		return void undefined; // step 7
+	}
+
+	return Get(O, ToString(k)); // step 8
+};
diff --git a/index.js b/index.js
@@ -0,0 +1,7 @@
+'use strict';
+
+var callBind = require('call-bind');
+
+var getPolyfill = require('./polyfill');
+
+module.exports = callBind(getPolyfill());
diff --git a/package.json b/package.json
@@ -1,13 +1,30 @@
 {
 	"name": "typedarray.prototype.at",
 	"version": "0.0.0",
-	"description": "An ES5 spec-compliant `TypedArray.prototype.at` shim/polyfill/replacement that works as far down as ES3",
+	"description": "An ES5 spec-compliant `%TypedArray%.prototype.at` shim/polyfill/replacement that works as far down as ES3.",
 	"main": "index.js",
 	"exports": {
+		".": "./index.js",
+		"./auto": "./auto.js",
+		"./polyfill": "./polyfill.js",
+		"./implementation": "./implementation.js",
+		"./shim": "./shim.js",
 		"./package.json": "./package.json"
 	},
 	"scripts": {
-		"test": "echo \"Error: no test specified\" && exit 1"
+		"prepack": "npmignore --auto --commentLines=autogenerated",
+		"prepublish": "not-in-publish || npm run prepublishOnly",
+		"prepublishOnly": "safe-publish-latest",
+		"preversion": "auto-changelog",
+		"prelint": "evalmd README.md",
+		"lint": "eslint --ext=js,mjs .",
+		"postlint": "es-shim-api --type=method",
+		"pretest": "npm run lint",
+		"test": "npm run tests-only",
+		"posttest": "npx npm@\">= 10.2\" audit --production",
+		"tests-only": "nyc tape 'test/**/*.js'",
+		"version": "auto-changelog && git add CHANGELOG.md",
+		"postversion": "auto-changelog && git add CHANGELOG.md && git commit --no-edit --amend && git tag -f \"v$(node -e \"console.log(require('./package.json').version)\")\""
 	},
 	"repository": {
 		"type": "git",
@@ -16,17 +33,61 @@
 	"keywords": [
 		"ecmascript",
 		"javascript",
-		"shim.polyfill",
+		"polyfill",
+		"shim",
 		"TypedArray",
-		"at",
 		"TypedArray.prototype.at",
-		"es-shim",
-		"API"
+		"at",
+		"ES5",
+		"es-shim API"
 	],
 	"author": "Jordan Harband <ljharb@gmail.com>",
+	"funding": {
+		"url": "https://github.com/sponsors/ljharb"
+	},
 	"license": "MIT",
 	"bugs": {
 		"url": "https://github.com/es-shims/TypedArray.prototype.at/issues"
 	},
-	"homepage": "https://github.com/es-shims/TypedArray.prototype.at#readme"
+	"homepage": "https://github.com/es-shims/TypedArray.prototype.at#readme",
+	"dependencies": {
+		"call-bind": "^1.0.8",
+		"define-properties": "^1.2.1",
+		"es-abstract": "^1.23.9",
+		"get-proto": "^1.0.1"
+	},
+	"devDependencies": {
+		"@es-shims/api": "^3.0.2",
+		"@ljharb/eslint-config": "^21.1.1",
+		"auto-changelog": "^2.5.0",
+		"encoding": "^0.1.13",
+		"es-value-fixtures": "^1.7.1",
+		"eslint": "=8.8.0",
+		"evalmd": "^0.0.19",
+		"for-each": "^0.3.5",
+		"functions-have-names": "^1.2.3",
+		"has-strict-mode": "^1.1.0",
+		"in-publish": "^2.0.1",
+		"npmignore": "^0.3.1",
+		"nyc": "^10.3.2",
+		"object-inspect": "^1.13.4",
+		"safe-publish-latest": "^2.0.0",
+		"tape": "^5.9.0"
+	},
+	"engines": {
+		"node": ">= 0.4"
+	},
+	"auto-changelog": {
+		"output": "CHANGELOG.md",
+		"template": "keepachangelog",
+		"unreleased": false,
+		"commitLimit": false,
+		"backfillLimit": false,
+		"hideCredit": true
+	},
+	"publishConfig": {
+		"ignore": [
+			".github/workflows"
+		]
+	}
 }
diff --git a/polyfill.js b/polyfill.js
diff --git a/shim.js b/shim.js
diff --git a/test/implementation.js b/test/implementation.js
diff --git a/test/index.js b/test/index.js
diff --git a/test/shimmed.js b/test/shimmed.js
diff --git a/test/tests.js b/test/tests.js

Original file line number	Diff line number	Diff line change
`@@ -1 +1,3 @@`
`1`	`1`	`package-lock=false`
	`2`	`+allow-same-version=true`
	`3`	`+message=v%s`