Assertions return boolean

.github/workflows/ci.yml

@@ -41,7 +41,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ts-version: [~3.7.5, ~3.8, ~3.9]
+        ts-version: [~3.7.5, ~3.8, ~3.9, ~4.0]
     steps:
       - uses: actions/checkout@v1
         with:

ava.config.js

@@ -1,4 +1,9 @@
+const skipTests = [];
+if (process.versions.node < '12.14.0') {
+	skipTests.push('!test/configurable-module-format/module.js');
+}
+
 export default {
-	files: ['test/**', '!test/**/{fixtures,helpers}/**'],
+	files: ['test/**', '!test/**/{fixtures,helpers}/**', ...skipTests],
 	ignoredByWatcher: ['{coverage,docs,media,test-d,test-tap}/**']
 };

docs/02-execution-context.md

@@ -24,7 +24,7 @@ Contains shared state from hooks.
 
 ## `t.passed`
 
-Whether a test has passed. This value is only accurate in the `test.afterEach()` and `test.afterEach.always()` hooks.
+When used in `test.afterEach()` or `test.afterEach.always()` hooks this tells you whether the test has passed. When used in a test itself (including teardown functions) this remains `true` until an assertion fails, the test has ended with an error, or a teardown function caused an error. This value has no meaning in other hooks.
 
 ## `t.end()`
 
@@ -36,7 +36,7 @@ Log values contextually alongside the test result instead of immediately printin
 
 ## `t.plan(count)`
 
-Plan how many assertion there are in the test. The test will fail if the actual assertion count doesn't match the number of planned assertions. See [assertion planning](./03-assertions.md#assertion-planning).
+Plan how many assertions there are in the test. The test will fail if the actual assertion count doesn't match the number of planned assertions. See [assertion planning](./03-assertions.md#assertion-planning).
 
 ## `t.teardown(fn)`
 

docs/03-assertions.md

@@ -244,7 +244,7 @@ Assert that an error is thrown. `fn` must be a function which should throw. The
 * `name`: the expected `.name` value of the thrown error
 * `code`: the expected `.code` value of the thrown error
 
-`expectation` does not need to be specified. If you don't need it but do want to set an assertion message you have to specify `null`.
+`expectation` does not need to be specified. If you don't need it but do want to set an assertion message you have to specify `undefined`. (AVA 3 also allows you to specify `null`. This will be removed in AVA 4. You can opt into this change early by enabling the `disableNullExpectations` experiment.)
 
 Example:
 
@@ -276,7 +276,7 @@ The thrown value *must* be an error. It is returned so you can run more assertio
 * `name`: the expected `.name` value of the thrown error
 * `code`: the expected `.code` value of the thrown error
 
-`expectation` does not need to be specified. If you don't need it but do want to set an assertion message you have to specify `null`.
+`expectation` does not need to be specified. If you don't need it but do want to set an assertion message you have to specify `undefined`. (AVA 3 also allows you to specify `null`. This will be removed in AVA 4. You can opt into this change early by enabling the `disableNullExpectations` experiment.)
 
 Example:
 

docs/06-configuration.md

@@ -52,7 +52,7 @@ Arguments passed to the CLI will always take precedence over the CLI options con
 - `tap`: if `true`, enables the [TAP reporter](./05-command-line.md#tap-reporter)
 - `verbose`: if `true`, enables verbose output
 - `snapshotDir`: specifies a fixed location for storing snapshot files. Use this if your snapshots are ending up in the wrong location
-- `extensions`: extensions of test files. Setting this overrides the default `["cjs", "mjs", "js"]` value, so make sure to include those extensions in the list
+- `extensions`: extensions of test files. Setting this overrides the default `["cjs", "mjs", "js"]` value, so make sure to include those extensions in the list. [Experimentally you can configure how files are loaded](#configuring-module-formats)
 - `require`: extra modules to require before tests are run. Modules are required in the [worker processes](./01-writing-tests.md#process-isolation)
 - `timeout`: Timeouts in AVA behave differently than in other test frameworks. AVA resets a timer after each test, forcing tests to quit if no new test results were received within the specified timeout. This can be used to handle stalled tests. See our [timeout documentation](./07-test-timeouts.md) for more options.
 - `nodeArguments`: Configure Node.js arguments used to launch worker processes.
@@ -213,6 +213,27 @@ export default {
 };
 ```
 
+### Configuring module formats
+
+Node.js can only load non-standard extension as ES Modules when using [experimental loaders](https://nodejs.org/docs/latest/api/esm.html#esm_experimental_loaders). To use this you'll also have to configure AVA to `import()` your test file.
+
+This is still an experimental feature. You can opt in to it by enabling the `configurableModuleFormat` experiment. Afterwards, you'll be able to specify per-extension module formats using an object form.
+
+As with the array form, you need to explicitly list `js`, `cjs`, and `mjs` extensions. These **must** be set using the `true` value; other extensions are configurable using either `'commonjs'` or `'module'`:
+
+`ava.config.js`:
+```js
+export default {
+	nonSemVerExperiments: {
+		configurableModuleFormat: true
+	},
+	extensions: {
+		js: true,
+		ts: 'module'
+	}
+};
+```
+
 ## Node arguments
 
 The `nodeArguments` configuration may be used to specify additional arguments for launching worker processes. These are combined with `--node-arguments` passed on the CLI and any arguments passed to the `node` binary when starting AVA.

docs/recipes/debugging-with-vscode.md

@@ -13,7 +13,7 @@ You can use VS Code's “JavaScript Debug Terminal” to automatically debug AVA
 
 ## Creating a launch configuration
 
-Alternatively you can create a lanch configuration, which makes it easier to debug individual test files.
+Alternatively you can create a launch configuration, which makes it easier to debug individual test files.
 
 1. Open a workspace for your project.
 1. In the sidebar click the *Debug* handle.

docs/recipes/react.md

@@ -26,21 +26,59 @@ You can find more information in [`@ava/babel`](https://github.com/avajs/babel).
 
 ## Using [Enzyme](https://github.com/airbnb/enzyme)
 
-Let's first see how to use AVA with one of the most popular React testing libraries: [Enzyme](https://github.com/airbnb/enzyme).
+Let's first see how to use AVA with one of the most popular React testing libraries: [Enzyme](https://github.com/enzymejs/enzyme).
 
 If you intend to only use [shallow component rendering](https://facebook.github.io/react/docs/test-utils.html#shallow-rendering), you don't need any extra setup.
 
-First install [Enzyme required packages](https://github.com/airbnb/enzyme/#installation):
+### Install Enzyme
+
+First install [Enzyme and its required adapter](https://github.com/enzymejs/enzyme#installation):
 
 ```console
-$ npm install --save-dev enzyme react-addons-test-utils react-dom
+$ npm install --save-dev enzyme enzyme-adapter-react-16
+```
+
+### Set up Enzyme
+
+Create a helper file, prefixed with an underscore. This ensures AVA does not treat it as a test.
+
+`test/_setup-enzyme-adapter.js`:
+
+```js
+const Enzyme = require('enzyme');
+const Adapter = require('enzyme-adapter-react-16');
+
+Enzyme.configure({
+	adapter: new Adapter()
+});
+```
+
+### Configure tests to use Enzyme
+
+Configure AVA to `require` the helper before every test file.
+
+**`package.json`:**
+
+```json
+{
+	"ava": {
+		"require": [
+			"./test/_setup-enzyme-adapter.js"
+		]
+	}
+}
 ```
 
+### Enjoy
+
 Then you can use Enzyme straight away:
 
+`test.js`:
+
 ```js
 const test = require('ava');
 const React = require('react');
+const PropTypes = require('prop-types');
 const {shallow} = require('enzyme');
 
 const Foo = ({children}) =>
@@ -51,7 +89,7 @@ const Foo = ({children}) =>
 	</div>;
 
 Foo.propTypes = {
-	children: React.PropTypes.any
+	children: PropTypes.any
 };
 
 test('has a .Foo class name', t => {
@@ -93,6 +131,7 @@ Usage example:
 ```js
 const test = require('ava');
 const React = require('react');
+const PropTypes = require('prop-types');
 const {renderJSX, JSX} = require('jsx-test-helpers');
 
 const Foo = ({children}) =>
@@ -103,7 +142,7 @@ const Foo = ({children}) =>
 	</div>;
 
 Foo.propTypes = {
-	children: React.PropTypes.any
+	children: PropTypes.any
 };
 
 test('renders correct markup', t => {

index.d.ts

@@ -433,7 +433,7 @@ export interface CbExecutionContext<Context = unknown> extends ExecutionContext<
 	end(error?: any): void;
 }
 
-export type ImplementationResult = PromiseLike<void> | Subscribable | void; // eslint-disable-line @typescript-eslint/no-invalid-void-type
+export type ImplementationResult = PromiseLike<void> | Subscribable | void;
 export type Implementation<Context = unknown> = (t: ExecutionContext<Context>) => ImplementationResult;
 export type CbImplementation<Context = unknown> = (t: CbExecutionContext<Context>) => ImplementationResult;