From 01d22e2807d00bfddc3f8e1867b7cd6c1f506aa3 Mon Sep 17 00:00:00 2001
From: Mark Wubben <mark@novemberborn.net>
Date: Mon, 1 Nov 2021 20:50:17 +0100
Subject: [PATCH 1/9] Simplify issue template

---
 .github/ISSUE_TEMPLATE/config.yml | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/.github/ISSUE_TEMPLATE/config.yml b/.github/ISSUE_TEMPLATE/config.yml
index 6f91954..0086358 100644
--- a/.github/ISSUE_TEMPLATE/config.yml
+++ b/.github/ISSUE_TEMPLATE/config.yml
@@ -1,8 +1 @@
 blank_issues_enabled: true
-contact_links:
-  - name: AVA on Spectrum
-    url: https://spectrum.chat/ava
-    about: Ask questions and discuss in our Spectrum community
-  - name: Stack Overflow
-    url: https://stackoverflow.com/questions/tagged/ava
-    about: Tag your question on Stack Overflow

From d508fb6673a3ab75cf3aba678c217f9c6ce5d606 Mon Sep 17 00:00:00 2001
From: Mark Wubben <mark@novemberborn.net>
Date: Mon, 1 Nov 2021 20:52:34 +0100
Subject: [PATCH 2/9] Upgrade XO and apply changes

---
 index.js                          | 42 +++++++++++++++----------------
 package.json                      |  6 +++--
 test/_with-provider.js            | 32 +++++++++++------------
 test/compilation.js               | 28 ++++++++++-----------
 test/fixtures/install-and-load.js |  5 ++--
 test/protocol-ava-3.2.js          |  2 +-
 6 files changed, 56 insertions(+), 59 deletions(-)

diff --git a/index.js b/index.js
index 8fc5369..1a027ea 100644
--- a/index.js
+++ b/index.js
@@ -44,7 +44,7 @@ const configProperties = {
 		required: true,
 		isValid(compile) {
 			return compile === false || compile === 'tsc';
-		}
+		},
 	},
 	rewritePaths: {
 		required: true,
@@ -53,20 +53,18 @@ const configProperties = {
 				return false;
 			}
 
-			return Object.entries(rewritePaths).every(([from, to]) => {
-				return from.endsWith('/') && typeof to === 'string' && to.endsWith('/');
-			});
-		}
+			return Object.entries(rewritePaths).every(([from, to]) => from.endsWith('/') && typeof to === 'string' && to.endsWith('/'));
+		},
 	},
 	extensions: {
 		required: false,
 		isValid(extensions) {
-			return Array.isArray(extensions) &&
-				extensions.length > 0 &&
-				extensions.every(ext => typeof ext === 'string' && ext !== '') &&
-				new Set(extensions).size === extensions.length;
-		}
-	}
+			return Array.isArray(extensions)
+				&& extensions.length > 0
+				&& extensions.every(ext => typeof ext === 'string' && ext !== '')
+				&& new Set(extensions).size === extensions.length;
+		},
+	},
 };
 
 module.exports = ({negotiateProtocol}) => {
@@ -86,12 +84,12 @@ module.exports = ({negotiateProtocol}) => {
 			const {
 				extensions = ['ts'],
 				rewritePaths: relativeRewritePaths,
-				compile
+				compile,
 			} = config;
 
 			const rewritePaths = Object.entries(relativeRewritePaths).map(([from, to]) => [
 				path.join(protocol.projectDir, from),
-				path.join(protocol.projectDir, to)
+				path.join(protocol.projectDir, to),
 			]);
 			const testFileExtension = new RegExp(`\\.(${extensions.map(ext => escapeStringRegexp(ext)).join('|')})$`);
 
@@ -102,13 +100,13 @@ module.exports = ({negotiateProtocol}) => {
 					}
 
 					return {
-						extensions: extensions.slice(),
-						rewritePaths: rewritePaths.slice()
+						extensions: [...extensions],
+						rewritePaths: [...rewritePaths],
 					};
 				},
 
 				get extensions() {
-					return extensions.slice();
+					return [...extensions];
 				},
 
 				ignoreChange(filePath) {
@@ -139,14 +137,14 @@ module.exports = ({negotiateProtocol}) => {
 						filePatterns: [
 							...filePatterns,
 							'!**/*.d.ts',
-							...Object.values(relativeRewritePaths).map(to => `!${to}**`)
+							...Object.values(relativeRewritePaths).map(to => `!${to}**`),
 						],
 						ignoredByWatcherPatterns: [
 							...ignoredByWatcherPatterns,
-							...Object.values(relativeRewritePaths).map(to => `${to}**/*.js.map`)
-						]
+							...Object.values(relativeRewritePaths).map(to => `${to}**/*.js.map`),
+						],
 					};
-				}
+				},
 			};
 		},
 
@@ -169,8 +167,8 @@ module.exports = ({negotiateProtocol}) => {
 					// TODO: Support JSX preserve mode — https://www.typescriptlang.org/docs/handbook/jsx.html
 					const rewritten = `${to}${ref.slice(from.length)}`.replace(testFileExtension, '.js');
 					return requireFn(rewritten);
-				}
+				},
 			};
-		}
+		},
 	};
 };
diff --git a/package.json b/package.json
index c88c33c..cc83afa 100644
--- a/package.json
+++ b/package.json
@@ -27,7 +27,7 @@
     "c8": "^7.7.1",
     "del": "^6.0.0",
     "typescript": "^4.2.4",
-    "xo": "^0.38.2"
+    "xo": "^0.46.3"
   },
   "c8": {
     "reporter": [
@@ -47,7 +47,9 @@
       "test/broken-fixtures"
     ],
     "rules": {
-      "import/order": "off"
+      "import/extensions": "off",
+      "import/order": "off",
+      "unicorn/prefer-module": "off"
     }
   }
 }
diff --git a/test/_with-provider.js b/test/_with-provider.js
index 9bc8089..39e6b2e 100644
--- a/test/_with-provider.js
+++ b/test/_with-provider.js
@@ -2,22 +2,20 @@ const path = require('path');
 const pkg = require('../package.json');
 const makeProvider = require('..');
 
-const createProviderMacro = (identifier, avaVersion, projectDir = __dirname) => {
-	return (t, run) => run(t, makeProvider({
-		negotiateProtocol(identifiers, {version}) {
-			t.true(identifiers.includes(identifier));
-			t.is(version, pkg.version);
-			return {
-				ava: {avaVersion},
-				identifier,
-				normalizeGlobPatterns: patterns => patterns,
-				async findFiles({patterns}) {
-					return patterns.map(file => path.join(projectDir, file));
-				},
-				projectDir
-			};
-		}
-	}));
-};
+const createProviderMacro = (identifier, avaVersion, projectDir = __dirname) => (t, run) => run(t, makeProvider({
+	negotiateProtocol(identifiers, {version}) {
+		t.true(identifiers.includes(identifier));
+		t.is(version, pkg.version);
+		return {
+			ava: {avaVersion},
+			identifier,
+			normalizeGlobPatterns: patterns => patterns,
+			async findFiles({patterns}) {
+				return patterns.map(file => path.join(projectDir, file));
+			},
+			projectDir,
+		};
+	},
+}));
 
 module.exports = createProviderMacro;
diff --git a/test/compilation.js b/test/compilation.js
index 0a791dd..3be563c 100644
--- a/test/compilation.js
+++ b/test/compilation.js
@@ -12,26 +12,24 @@ test.before('deleting compiled files', async t => {
 	t.log(await del('test/broken-fixtures/typescript/compiled'));
 });
 
-const compile = async provider => {
-	return {
-		state: await provider.main({
-			config: {
-				rewritePaths: {
-					'ts/': 'typescript/',
-					'compiled/': 'typescript/compiled/'
-				},
-				compile: 'tsc'
-			}
-		}).compile()
-	};
-};
+const compile = async provider => ({
+	state: await provider.main({
+		config: {
+			rewritePaths: {
+				'ts/': 'typescript/',
+				'compiled/': 'typescript/compiled/',
+			},
+			compile: 'tsc',
+		},
+	}).compile(),
+});
 
 test('worker(): load rewritten paths files', withProvider, async (t, provider) => {
 	const {state} = await compile(provider);
 	const {stdout, stderr} = await execa.node(
 		path.join(__dirname, 'fixtures/install-and-load'),
 		[JSON.stringify(state), path.join(__dirname, 'fixtures/ts', 'file.ts')],
-		{cwd: path.join(__dirname, 'fixtures')}
+		{cwd: path.join(__dirname, 'fixtures')},
 	);
 	if (stderr.length > 0) {
 		t.log(stderr);
@@ -45,7 +43,7 @@ test('worker(): runs compiled files', withProvider, async (t, provider) => {
 	const {stdout, stderr} = await execa.node(
 		path.join(__dirname, 'fixtures/install-and-load'),
 		[JSON.stringify(state), path.join(__dirname, 'fixtures/compiled', 'index.ts')],
-		{cwd: path.join(__dirname, 'fixtures')}
+		{cwd: path.join(__dirname, 'fixtures')},
 	);
 	if (stderr.length > 0) {
 		t.log(stderr);
diff --git a/test/fixtures/install-and-load.js b/test/fixtures/install-and-load.js
index 5e1f26c..d95ec87 100644
--- a/test/fixtures/install-and-load.js
+++ b/test/fixtures/install-and-load.js
@@ -1,15 +1,16 @@
 const path = require('path');
+const process = require('process');
 const makeProvider = require('../..');
 
 const provider = makeProvider({
 	negotiateProtocol() {
 		return {identifier: 'ava-3.2', ava: {version: '3.15.0'}, projectDir: __dirname};
-	}
+	},
 });
 
 const worker = provider.worker({
 	extensionsToLoadAsModules: [],
-	state: JSON.parse(process.argv[2])
+	state: JSON.parse(process.argv[2]),
 });
 
 const ref = path.resolve(process.argv[3]);
diff --git a/test/protocol-ava-3.2.js b/test/protocol-ava-3.2.js
index 476895f..fa4281b 100644
--- a/test/protocol-ava-3.2.js
+++ b/test/protocol-ava-3.2.js
@@ -81,6 +81,6 @@ test('main() updateGlobs()', withProvider, (t, provider) => {
 	const main = provider.main({config: {rewritePaths: {'src/': 'build/'}, compile: false}});
 	t.snapshot(main.updateGlobs({
 		filePatterns: ['src/test.ts'],
-		ignoredByWatcherPatterns: ['assets/**']
+		ignoredByWatcherPatterns: ['assets/**'],
 	}));
 });

From 5560c2518065c9c7c086299f5329bae61c68468f Mon Sep 17 00:00:00 2001
From: Mark Wubben <mark@novemberborn.net>
Date: Mon, 1 Nov 2021 20:53:37 +0100
Subject: [PATCH 3/9] Update dependencies

---
 package.json                            |   8 ++++----
 test/snapshots/compilation.js.snap      | Bin 284 -> 303 bytes
 test/snapshots/protocol-ava-3.2.js.snap | Bin 738 -> 756 bytes
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/package.json b/package.json
index cc83afa..4c88f5c 100644
--- a/package.json
+++ b/package.json
@@ -20,13 +20,13 @@
   },
   "dependencies": {
     "escape-string-regexp": "^4.0.0",
-    "execa": "^5.0.0"
+    "execa": "^5.1.1"
   },
   "devDependencies": {
-    "ava": "^3.15.0",
-    "c8": "^7.7.1",
+    "ava": "4.0.0-rc.1",
+    "c8": "^7.10.0",
     "del": "^6.0.0",
-    "typescript": "^4.2.4",
+    "typescript": "^4.4.4",
     "xo": "^0.46.3"
   },
   "c8": {
diff --git a/test/snapshots/compilation.js.snap b/test/snapshots/compilation.js.snap
index 1d4c4eda42693aee7cdbddc2638609b68826f39e..9171aa333cc64d20e81c90be6ea85a5bbb0f8d9e 100644
GIT binary patch
literal 303
zcmV+~0nq+IRzV<BZeeh9Xm4~Nb~6eC06C!S(MIkVm%+^bbq^LuGLdr+{-cveFMB1<
z4cC2+A|Hzg00000000AZkHJpDKoCGn3^DP>2N>pHq$E-VIrYjX=)vpQ9q7t-w%M7c
z^=SAK{8HCO0>n6{IZWPrbJ)B&U+iT6MQYVich~x`qmWK>a2^c=YJ*iJh8ndL*jPtm
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z+01egs3KN$H)r<K8WYmR!y^9Jd*S7I`SiHTVU5gQV|sKjRs<8AWZ(Mo5fg#|007I2
Bm9YQ-

literal 284
zcmV+%0ptEbRzV<BZeeh9Xm4~Nb}|YA0H)o?dT(pg`6XmWVZ~dd>mQ2<000000009E
zVPIfjX7DZG_h>lz^`yk==h7;_AHHW~009#quFJABdvy0#)aO7O=8IE4XflFDgMoPE
zxvtXB_X7B~Tdj6jbo}T}MzH8LuzBoY{fw*(f{bc8`RVDYDGHf+3Tc@YC8b5F#rh?c
z1*yf!MVSR9`k8qtsTF!9#VC3Nk@e)H>SduympbR?<|gK)D5NC<Wm6Q&GfOfQQY$h`
z6q55(QWcD>6iSMd6?Ano^OB2Fb5rw55_7natVA$@_G%dF7;0K6q!tzB7b%1U8yOpz
iSSdIs=H=y=0PP0ak(Zd8s-T{zt_J`Mn{bIL0RR9UyMMj_

diff --git a/test/snapshots/protocol-ava-3.2.js.snap b/test/snapshots/protocol-ava-3.2.js.snap
index 1e9982c6d786e2920d8fc33c830852e8b9ff307d..df5d750c263db1c2bb8361d6bada36e5e552c2a5 100644
GIT binary patch
literal 756
zcmV<Q0t@{?RzV<BZeeh9Xm4~Nb~6eC0J4%V`;vmdZ(9<?TVlGK-E_to+^}}p>nHiq
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mhkmu1ZCo1Oc!~jV3z>Xq+quFL_ud9CVfr6`iB?@V5C8yMZFbQB

literal 738
zcmV<80v-K9RzV<BZeeh9Xm4~Nb}|YA0O+H_HspE{tW@J71B8x4{U3`600000000B+
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z0aSpzgRi?eLL6(r<^@}OIDsP!pcr~Q9t5ipNC;K~407RGkP(!7!4=b!_@KrZCI%JR
zu_alb9yd&aqs^HfjYWDf`K7FYvbS9Mo?~8A<To!55~5{5DnxF#Tbxqmf}I@g%Y^c8
zLMO`Z?BWWkc!)|$A}Yg_1sKie018QGjo+{O1JNZpsgQHjg!}YlRQ3BsV`+I~hej!8
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zIx$vy8MA1Es>XHJ+ZPT*%#^C7wFFfeFQ=kh4JXa8nywwNPR0XiOek-1M(t<~?rm!g
zq@sV);xKB{Db<a*QpZnb@k_VjJOW+v6}yTDD)}k-Dfub=BT61umdAZYT1)EDlE;7C
U<Nt71{|=8o0S*B0Qq2tj0C?h8g#Z8m


From f958b1878f124358746fb2955126d4d4cdc076ff Mon Sep 17 00:00:00 2001
From: Mark Wubben <mark@novemberborn.net>
Date: Mon, 1 Nov 2021 21:07:39 +0100
Subject: [PATCH 4/9] Upgrade to ESM

---
 index.js                              | 14 +++++++-------
 package.json                          | 13 ++++++-------
 test/_with-provider.js                | 12 ++++++++----
 test/base.js                          |  4 ++--
 test/compilation.js                   | 14 ++++++++------
 test/fixtures/install-and-load.js     | 12 ++++++++----
 test/fixtures/typescript/package.json |  3 +++
 test/protocol-ava-3.2.js              | 13 ++++++++-----
 8 files changed, 50 insertions(+), 35 deletions(-)
 create mode 100644 test/fixtures/typescript/package.json

diff --git a/index.js b/index.js
index 1a027ea..c3c66c0 100644
--- a/index.js
+++ b/index.js
@@ -1,9 +1,9 @@
-'use strict';
-const path = require('path');
-const escapeStringRegexp = require('escape-string-regexp');
-const execa = require('execa');
-const pkg = require('./package.json');
+import fs from 'node:fs';
+import path from 'node:path';
+import escapeStringRegexp from 'escape-string-regexp';
+import execa from 'execa';
 
+const pkg = fs.readFileSync(new URL('package.json', import.meta.url));
 const help = `See https://github.com/avajs/typescript/blob/v${pkg.version}/README.md`;
 
 function isPlainObject(x) {
@@ -67,7 +67,7 @@ const configProperties = {
 	},
 };
 
-module.exports = ({negotiateProtocol}) => {
+export default function typescriptProvider({negotiateProtocol}) {
 	const protocol = negotiateProtocol(['ava-3.2'], {version: pkg.version});
 	if (protocol === null) {
 		return;
@@ -171,4 +171,4 @@ module.exports = ({negotiateProtocol}) => {
 			};
 		},
 	};
-};
+}
diff --git a/package.json b/package.json
index 4c88f5c..9cd4823 100644
--- a/package.json
+++ b/package.json
@@ -8,6 +8,10 @@
   "files": [
     "index.js"
   ],
+  "exports": {
+    ".": "./index.js"
+  },
+  "type": "module",
   "author": "Mark Wubben (https://novemberborn.net)",
   "repository": "avajs/typescript",
   "license": "MIT",
@@ -19,7 +23,7 @@
     "test": "xo && c8 ava"
   },
   "dependencies": {
-    "escape-string-regexp": "^4.0.0",
+    "escape-string-regexp": "^5.0.0",
     "execa": "^5.1.1"
   },
   "devDependencies": {
@@ -45,11 +49,6 @@
   "xo": {
     "ignores": [
       "test/broken-fixtures"
-    ],
-    "rules": {
-      "import/extensions": "off",
-      "import/order": "off",
-      "unicorn/prefer-module": "off"
-    }
+    ]
   }
 }
diff --git a/test/_with-provider.js b/test/_with-provider.js
index 39e6b2e..673be3f 100644
--- a/test/_with-provider.js
+++ b/test/_with-provider.js
@@ -1,6 +1,10 @@
-const path = require('path');
-const pkg = require('../package.json');
-const makeProvider = require('..');
+import fs from 'node:fs';
+import path from 'node:path';
+import {fileURLToPath} from 'node:url';
+import makeProvider from '@ava/typescript';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const pkg = fs.readFileSync(new URL('../package.json', import.meta.url));
 
 const createProviderMacro = (identifier, avaVersion, projectDir = __dirname) => (t, run) => run(t, makeProvider({
 	negotiateProtocol(identifiers, {version}) {
@@ -18,4 +22,4 @@ const createProviderMacro = (identifier, avaVersion, projectDir = __dirname) =>
 	},
 }));
 
-module.exports = createProviderMacro;
+export default createProviderMacro;
diff --git a/test/base.js b/test/base.js
index d3344e5..1fb0df1 100644
--- a/test/base.js
+++ b/test/base.js
@@ -1,5 +1,5 @@
-const test = require('ava');
-const makeProvider = require('..');
+import test from 'ava';
+import makeProvider from '@ava/typescript';
 
 test('bails when negotiating protocol returns `null`', t => {
 	const provider = makeProvider({negotiateProtocol: () => null});
diff --git a/test/compilation.js b/test/compilation.js
index 3be563c..dddb2da 100644
--- a/test/compilation.js
+++ b/test/compilation.js
@@ -1,9 +1,11 @@
-const path = require('path');
-const test = require('ava');
-const del = require('del');
-const execa = require('execa');
-const createProviderMacro = require('./_with-provider');
-
+import path from 'node:path';
+import {fileURLToPath} from 'node:url';
+import test from 'ava';
+import del from 'del';
+import execa from 'execa';
+import createProviderMacro from './_with-provider.js';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
 const withProvider = createProviderMacro('ava-3.2', '3.2.0', path.join(__dirname, 'fixtures'));
 const withAltProvider = createProviderMacro('ava-3.2', '3.2.0', path.join(__dirname, 'broken-fixtures'));
 
diff --git a/test/fixtures/install-and-load.js b/test/fixtures/install-and-load.js
index d95ec87..08217bb 100644
--- a/test/fixtures/install-and-load.js
+++ b/test/fixtures/install-and-load.js
@@ -1,6 +1,10 @@
-const path = require('path');
-const process = require('process');
-const makeProvider = require('../..');
+import {createRequire} from 'node:module';
+import path from 'node:path';
+import process from 'node:process';
+import {fileURLToPath} from 'node:url';
+import makeProvider from '@ava/typescript';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
 
 const provider = makeProvider({
 	negotiateProtocol() {
@@ -16,5 +20,5 @@ const worker = provider.worker({
 const ref = path.resolve(process.argv[3]);
 
 if (worker.canLoad(ref)) {
-	worker.load(ref, {requireFn: require});
+	worker.load(ref, {requireFn: createRequire(import.meta.url)});
 }
diff --git a/test/fixtures/typescript/package.json b/test/fixtures/typescript/package.json
new file mode 100644
index 0000000..5bbefff
--- /dev/null
+++ b/test/fixtures/typescript/package.json
@@ -0,0 +1,3 @@
+{
+  "type": "commonjs"
+}
diff --git a/test/protocol-ava-3.2.js b/test/protocol-ava-3.2.js
index fa4281b..366ba1b 100644
--- a/test/protocol-ava-3.2.js
+++ b/test/protocol-ava-3.2.js
@@ -1,8 +1,11 @@
-const path = require('path');
-const test = require('ava');
-const pkg = require('../package.json');
-const createProviderMacro = require('./_with-provider');
-
+import fs from 'node:fs';
+import path from 'node:path';
+import {fileURLToPath} from 'node:url';
+import test from 'ava';
+import createProviderMacro from './_with-provider.js';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const pkg = fs.readFileSync(new URL('../package.json', import.meta.url));
 const withProvider = createProviderMacro('ava-3.2', '3.15.0');
 
 const validateConfig = (t, provider, config) => {

From 8b22ed3ed24b9acc278505208d3df15d5cebb88a Mon Sep 17 00:00:00 2001
From: Mark Wubben <mark@novemberborn.net>
Date: Mon, 1 Nov 2021 21:08:49 +0100
Subject: [PATCH 5/9] Match AVA 4 Node.js versions

---
 .github/workflows/ci.yml | 2 +-
 package.json             | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4c247ee..250a51d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        node-version: [^12.22, ^14.16, ^15]
+        node-version: [^12.22, ^14.17, ^16.4, ^17]
         os: [ubuntu-latest, windows-latest]
     steps:
       - uses: actions/checkout@v1
diff --git a/package.json b/package.json
index 9cd4823..c064fcb 100644
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
   "version": "2.0.0",
   "description": "TypeScript provider for AVA",
   "engines": {
-    "node": ">=12.22 <13 || >=14.16 <15 || >=15"
+    "node": ">=12.22 <13 || >=14.17 <15 || >=16.4 <17 || >=17"
   },
   "files": [
     "index.js"

From 3debd9d8e81367c6949fe290944fb38d9296a879 Mon Sep 17 00:00:00 2001
From: Mark Wubben <mark@novemberborn.net>
Date: Mon, 1 Nov 2021 21:08:55 +0100
Subject: [PATCH 6/9] Update CI

---
 .github/workflows/ci.yml | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 250a51d..cd5d2cd 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,12 +16,13 @@ jobs:
         node-version: [^12.22, ^14.17, ^16.4, ^17]
         os: [ubuntu-latest, windows-latest]
     steps:
-      - uses: actions/checkout@v1
-        with:
-          fetch-depth: 1
-      - uses: actions/setup-node@v1
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
         with:
           node-version: ${{ matrix.node-version }}
       - run: npm install --no-audit
       - run: npm test
-      - uses: codecov/codecov-action@v1
+      - uses: codecov/codecov-action@v2
+        with:
+          files: coverage/lcov.info
+          name: ${{ matrix.os }}/${{ matrix.node-version }}

From 407378175469625ec77d51d6416975feff38bcde Mon Sep 17 00:00:00 2001
From: Mark Wubben <mark@novemberborn.net>
Date: Mon, 1 Nov 2021 21:39:57 +0100
Subject: [PATCH 7/9] Support ESM files

Fixes #5.
---
 README.md                         |   4 ++++
 index.js                          |  10 +++------
 package.json                      |   4 ++++
 test/compilation.js               |   4 ++--
 test/esm.js                       |  33 ++++++++++++++++++++++++++++++
 test/fixtures/esm/index.js        |   1 +
 test/fixtures/esm/index.ts        |   1 +
 test/fixtures/esm/tsconfig.json   |   8 ++++++++
 test/fixtures/install-and-load.js |   3 ++-
 test/snapshots/esm.js.md          |  11 ++++++++++
 test/snapshots/esm.js.snap        | Bin 0 -> 169 bytes
 11 files changed, 69 insertions(+), 10 deletions(-)
 create mode 100644 test/esm.js
 create mode 100644 test/fixtures/esm/index.js
 create mode 100644 test/fixtures/esm/index.ts
 create mode 100644 test/fixtures/esm/tsconfig.json
 create mode 100644 test/snapshots/esm.js.md
 create mode 100644 test/snapshots/esm.js.snap

diff --git a/README.md b/README.md
index 4466038..c0452b5 100644
--- a/README.md
+++ b/README.md
@@ -39,6 +39,10 @@ Output files are expected to have the `.js` extension.
 
 AVA searches your entire project for `*.js`, `*.cjs`, `*.mjs` and `*.ts` files (or other extensions you've configured). It will ignore such files found in the `rewritePaths` targets (e.g. `build/`). If you use more specific paths, for instance `build/main/`, you may need to change AVA's `files` configuration to ignore other directories.
 
+## ES Modules
+
+When used with AVA 4, if your `package.json` has configured `"type": "module"`, or you've configured AVA to treat the `js` extension as `module`, then `@ava/typescript` will import the output file as an ES module. Note that this is based on the *output file*, not the `ts` extension.
+
 ## Add additional extensions
 
 You can configure AVA to recognize additional file extensions. To add (partial†) JSX support:
diff --git a/index.js b/index.js
index c3c66c0..d27d1b0 100644
--- a/index.js
+++ b/index.js
@@ -1,5 +1,6 @@
 import fs from 'node:fs';
 import path from 'node:path';
+import {pathToFileURL} from 'node:url';
 import escapeStringRegexp from 'escape-string-regexp';
 import execa from 'execa';
 
@@ -149,6 +150,7 @@ export default function typescriptProvider({negotiateProtocol}) {
 		},
 
 		worker({extensionsToLoadAsModules, state: {extensions, rewritePaths}}) {
+			const useImport = extensionsToLoadAsModules.includes('js');
 			const testFileExtension = new RegExp(`\\.(${extensions.map(ext => escapeStringRegexp(ext)).join('|')})$`);
 
 			return {
@@ -157,16 +159,10 @@ export default function typescriptProvider({negotiateProtocol}) {
 				},
 
 				async load(ref, {requireFn}) {
-					for (const extension of extensionsToLoadAsModules) {
-						if (ref.endsWith(`.${extension}`)) {
-							throw new Error('@ava/typescript cannot yet load ESM files');
-						}
-					}
-
 					const [from, to] = rewritePaths.find(([from]) => ref.startsWith(from));
 					// TODO: Support JSX preserve mode — https://www.typescriptlang.org/docs/handbook/jsx.html
 					const rewritten = `${to}${ref.slice(from.length)}`.replace(testFileExtension, '.js');
-					return requireFn(rewritten);
+					return useImport ? import(pathToFileURL(rewritten)) : requireFn(rewritten); // eslint-disable-line node/no-unsupported-features/es-syntax
 				},
 			};
 		},
diff --git a/package.json b/package.json
index c064fcb..35fb797 100644
--- a/package.json
+++ b/package.json
@@ -44,6 +44,10 @@
     "files": [
       "!test/broken-fixtures/**"
     ],
+    "ignoredByWatcher": [
+      "test/fixtures/**",
+      "test/broken-fixtures/**"
+    ],
     "timeout": "60s"
   },
   "xo": {
diff --git a/test/compilation.js b/test/compilation.js
index dddb2da..6cf9257 100644
--- a/test/compilation.js
+++ b/test/compilation.js
@@ -30,7 +30,7 @@ test('worker(): load rewritten paths files', withProvider, async (t, provider) =
 	const {state} = await compile(provider);
 	const {stdout, stderr} = await execa.node(
 		path.join(__dirname, 'fixtures/install-and-load'),
-		[JSON.stringify(state), path.join(__dirname, 'fixtures/ts', 'file.ts')],
+		[JSON.stringify({state}), path.join(__dirname, 'fixtures/ts', 'file.ts')],
 		{cwd: path.join(__dirname, 'fixtures')},
 	);
 	if (stderr.length > 0) {
@@ -44,7 +44,7 @@ test('worker(): runs compiled files', withProvider, async (t, provider) => {
 	const {state} = await compile(provider);
 	const {stdout, stderr} = await execa.node(
 		path.join(__dirname, 'fixtures/install-and-load'),
-		[JSON.stringify(state), path.join(__dirname, 'fixtures/compiled', 'index.ts')],
+		[JSON.stringify({state}), path.join(__dirname, 'fixtures/compiled', 'index.ts')],
 		{cwd: path.join(__dirname, 'fixtures')},
 	);
 	if (stderr.length > 0) {
diff --git a/test/esm.js b/test/esm.js
new file mode 100644
index 0000000..4d9d5e3
--- /dev/null
+++ b/test/esm.js
@@ -0,0 +1,33 @@
+import path from 'node:path';
+import {fileURLToPath} from 'node:url';
+import test from 'ava';
+import execa from 'execa';
+import createProviderMacro from './_with-provider.js';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const withProvider = createProviderMacro('ava-3.2', '3.2.0', path.join(__dirname, 'fixtures'));
+
+const setup = async provider => ({
+	state: await provider.main({
+		config: {
+			rewritePaths: {
+				'esm/': 'esm/',
+			},
+			compile: false,
+		},
+	}).compile(),
+});
+
+test('worker(): import ESM', withProvider, async (t, provider) => {
+	const {state} = await setup(provider);
+	const {stdout, stderr} = await execa.node(
+		path.join(__dirname, 'fixtures/install-and-load'),
+		[JSON.stringify({extensionsToLoadAsModules: ['js'], state}), path.join(__dirname, 'fixtures/esm', 'index.ts')],
+		{cwd: path.join(__dirname, 'fixtures')},
+	);
+	if (stderr.length > 0) {
+		t.log(stderr);
+	}
+
+	t.snapshot(stdout);
+});
diff --git a/test/fixtures/esm/index.js b/test/fixtures/esm/index.js
new file mode 100644
index 0000000..b8a2e5c
--- /dev/null
+++ b/test/fixtures/esm/index.js
@@ -0,0 +1 @@
+console.log('logged in fixtures/esm/index.js');
diff --git a/test/fixtures/esm/index.ts b/test/fixtures/esm/index.ts
new file mode 100644
index 0000000..ed203aa
--- /dev/null
+++ b/test/fixtures/esm/index.ts
@@ -0,0 +1 @@
+console.log('logged in fixtures/esm/index.ts');
diff --git a/test/fixtures/esm/tsconfig.json b/test/fixtures/esm/tsconfig.json
new file mode 100644
index 0000000..41da438
--- /dev/null
+++ b/test/fixtures/esm/tsconfig.json
@@ -0,0 +1,8 @@
+{
+	"compilerOptions": {
+		"outDir": "compiled"
+	},
+	"include": [
+		"."
+	]
+}
diff --git a/test/fixtures/install-and-load.js b/test/fixtures/install-and-load.js
index 08217bb..c92a633 100644
--- a/test/fixtures/install-and-load.js
+++ b/test/fixtures/install-and-load.js
@@ -14,7 +14,8 @@ const provider = makeProvider({
 
 const worker = provider.worker({
 	extensionsToLoadAsModules: [],
-	state: JSON.parse(process.argv[2]),
+	state: {},
+	...JSON.parse(process.argv[2]),
 });
 
 const ref = path.resolve(process.argv[3]);
diff --git a/test/snapshots/esm.js.md b/test/snapshots/esm.js.md
new file mode 100644
index 0000000..1642bed
--- /dev/null
+++ b/test/snapshots/esm.js.md
@@ -0,0 +1,11 @@
+# Snapshot report for `test/esm.js`
+
+The actual snapshot is saved in `esm.js.snap`.
+
+Generated by [AVA](https://avajs.dev).
+
+## worker(): import ESM
+
+> Snapshot 1
+
+    'logged in fixtures/esm/index.js'
diff --git a/test/snapshots/esm.js.snap b/test/snapshots/esm.js.snap
new file mode 100644
index 0000000000000000000000000000000000000000..d31fee50dc3c121aa0c9c8c46f7238150160a77f
GIT binary patch
literal 169
zcmV;a09OA&RzV<BZeeh9Xm4~Nb~6eC0AeXKkxUUNlBNk2U50so+uASnw-lE-z%olV
zCNx|1Hy?`#00000000A9n3j~2pPXIXxG1$Gvm__Aq&&YUJGDqd(@G&Tw;;c$M8P%K
zH?ue|v7k63zofWvVM<D3Nn(U9GXpyV2r#lT2r|m&<fo^nrYL0QDWqjql#~{w7VD=L
X=jvzXrKDEqWfcPe5@hY*WdHyG<`+WH

literal 0
HcmV?d00001


From 21be95c0e667d62062eddea4c52da0183a4d97fa Mon Sep 17 00:00:00 2001
From: Mark Wubben <mark@novemberborn.net>
Date: Tue, 2 Nov 2021 20:34:57 +0100
Subject: [PATCH 8/9] Test using npm@8

---
 .github/workflows/ci.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index cd5d2cd..0800452 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,6 +20,7 @@ jobs:
       - uses: actions/setup-node@v2
         with:
           node-version: ${{ matrix.node-version }}
+      - run: npm install --global npm@8
       - run: npm install --no-audit
       - run: npm test
       - uses: codecov/codecov-action@v2

From cebe60bd8a6ef36b2ca4efd7020a9854d7665090 Mon Sep 17 00:00:00 2001
From: Mark Wubben <mark@novemberborn.net>
Date: Tue, 2 Nov 2021 20:35:08 +0100
Subject: [PATCH 9/9] Fix branch reference

---
 .github/workflows/ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0800452..c336669 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -2,7 +2,7 @@ name: Install and test @ava/typescript
 on:
   push:
     branches:
-    - master
+    - main
   pull_request:
     paths-ignore:
     - '*.md'