Add this.error() method in plugin context

.changeset/eight-teachers-sit.md

@@ -0,0 +1,5 @@
+---
+'wmr': patch
+---
+
+Fix missing `this.error()` method in Rollup plugins

packages/wmr/src/lib/rollup-plugin-container.js

@@ -156,6 +156,16 @@ export function createPluginContainer(plugins, opts = {}) {
 		warn(...args) {
 			// eslint-disable-next-line no-console
 			console.log(`[${plugin.name}]`, ...args);
+		},
+		// Rollup has typed the return value as `never` because they
+		// throw and abort the build. Doing that in "development"
+		// mode would be very annoying so we intentionally have a
+		// type mismatch.
+		// @ts-ignore
+		error(err) {
+			if (typeof err === 'string') err = { message: err };
+			// eslint-disable-next-line no-console
+			console.log(`[${plugin.name}]`, err.message);
 		}
 	};
 

packages/wmr/test/fixtures/plugin-error/public/index.html

@@ -0,0 +1,2 @@
+<h1>check console</h1>
+<script type="module" src="index.js"></script>

packages/wmr/test/fixtures/plugin-error/wmr.config.mjs

@@ -0,0 +1,16 @@
+export default {
+	plugins: [
+		{
+			name: 'plugin-a',
+			resolveId() {
+				this.error(`oh no #1`);
+			},
+			load() {
+				this.error(`oh no #2`);
+			},
+			transform() {
+				this.error(`oh no #3`);
+			}
+		}
+	]
+};

packages/wmr/test/plugins/plugins.test.js

@@ -1,4 +1,4 @@
-import { loadFixture, runWmrFast, setupTest, teardown, waitForMessage, withLog } from '../test-helpers.js';
+import { getOutput, loadFixture, runWmrFast, setupTest, teardown, waitForMessage, withLog } from '../test-helpers.js';
 
 jest.setTimeout(30000);
 
@@ -45,5 +45,14 @@ describe('config', () => {
 				await waitForMessage(instance.output, /OPTIONS format: esm/);
 			});
 		});
+
+		it('should support `this.error()`', async () => {
+			await loadFixture('plugin-error', env);
+			instance = await runWmrFast(env.tmp.path);
+			await getOutput(env, instance);
+			await waitForMessage(instance.output, /oh no #1/);
+			await waitForMessage(instance.output, /oh no #2/);
+			await waitForMessage(instance.output, /oh no #3/);
+		});
 	});
 });