core(lantern): add LanternError and adapter to LH error

core/computed/metrics/lantern-first-contentful-paint.js

@@ -5,7 +5,7 @@
  */
 
 import {makeComputedArtifact} from '../computed-artifact.js';
-import {getComputationDataParams} from './lantern-metric.js';
+import {getComputationDataParams, lanternErrorAdapter} from './lantern-metric.js';
 import {FirstContentfulPaint} from '../../lib/lantern/metrics/first-contentful-paint.js';
 
 /** @typedef {import('../../lib/lantern/metric.js').Extras} Extras */
@@ -18,7 +18,8 @@ class LanternFirstContentfulPaint extends FirstContentfulPaint {
    * @return {Promise<LH.Artifacts.LanternMetric>}
    */
   static async computeMetricWithGraphs(data, context, extras) {
-    return this.compute(await getComputationDataParams(data, context), extras);
+    return this.compute(await getComputationDataParams(data, context), extras)
+      .catch(lanternErrorAdapter);
   }
 
   /**

core/computed/metrics/lantern-first-meaningful-paint.js

@@ -5,7 +5,7 @@
  */
 
 import {makeComputedArtifact} from '../computed-artifact.js';
-import {getComputationDataParams} from './lantern-metric.js';
+import {getComputationDataParams, lanternErrorAdapter} from './lantern-metric.js';
 import {FirstMeaningfulPaint} from '../../lib/lantern/metrics/first-meaningful-paint.js';
 import {LanternFirstContentfulPaint} from './lantern-first-contentful-paint.js';
 
@@ -19,7 +19,8 @@ class LanternFirstMeaningfulPaint extends FirstMeaningfulPaint {
    * @return {Promise<LH.Artifacts.LanternMetric>}
    */
   static async computeMetricWithGraphs(data, context, extras) {
-    return this.compute(await getComputationDataParams(data, context), extras);
+    return this.compute(await getComputationDataParams(data, context), extras)
+      .catch(lanternErrorAdapter);
   }
 
   /**

core/computed/metrics/lantern-interactive.js

@@ -7,7 +7,7 @@
 import {makeComputedArtifact} from '../computed-artifact.js';
 import {LanternFirstMeaningfulPaint} from './lantern-first-meaningful-paint.js';
 import {Interactive} from '../../lib/lantern/metrics/interactive.js';
-import {getComputationDataParams} from './lantern-metric.js';
+import {getComputationDataParams, lanternErrorAdapter} from './lantern-metric.js';
 
 /** @typedef {import('../../lib/lantern/metric.js').Extras} Extras */
 
@@ -19,7 +19,8 @@ class LanternInteractive extends Interactive {
    * @return {Promise<LH.Artifacts.LanternMetric>}
    */
   static async computeMetricWithGraphs(data, context, extras) {
-    return this.compute(await getComputationDataParams(data, context), extras);
+    return this.compute(await getComputationDataParams(data, context), extras)
+      .catch(lanternErrorAdapter);
   }
 
   /**

core/computed/metrics/lantern-largest-contentful-paint.js

@@ -6,7 +6,7 @@
 
 import {makeComputedArtifact} from '../computed-artifact.js';
 import {LargestContentfulPaint} from '../../lib/lantern/metrics/largest-contentful-paint.js';
-import {getComputationDataParams} from './lantern-metric.js';
+import {getComputationDataParams, lanternErrorAdapter} from './lantern-metric.js';
 import {LanternFirstContentfulPaint} from './lantern-first-contentful-paint.js';
 
 /** @typedef {import('../../lib/lantern/metric.js').Extras} Extras */
@@ -19,7 +19,8 @@ class LanternLargestContentfulPaint extends LargestContentfulPaint {
    * @return {Promise<LH.Artifacts.LanternMetric>}
    */
   static async computeMetricWithGraphs(data, context, extras) {
-    return this.compute(await getComputationDataParams(data, context), extras);
+    return this.compute(await getComputationDataParams(data, context), extras)
+      .catch(lanternErrorAdapter);
   }
 
   /**

core/computed/metrics/lantern-max-potential-fid.js

@@ -6,7 +6,7 @@
 
 import {makeComputedArtifact} from '../computed-artifact.js';
 import {MaxPotentialFID} from '../../lib/lantern/metrics/max-potential-fid.js';
-import {getComputationDataParams} from './lantern-metric.js';
+import {getComputationDataParams, lanternErrorAdapter} from './lantern-metric.js';
 import {LanternFirstContentfulPaint} from './lantern-first-contentful-paint.js';
 
 /** @typedef {import('../../lib/lantern/metric.js').Extras} Extras */
@@ -19,7 +19,8 @@ class LanternMaxPotentialFID extends MaxPotentialFID {
    * @return {Promise<LH.Artifacts.LanternMetric>}
    */
   static async computeMetricWithGraphs(data, context, extras) {
-    return this.compute(await getComputationDataParams(data, context), extras);
+    return this.compute(await getComputationDataParams(data, context), extras)
+      .catch(lanternErrorAdapter);
   }
 
   /**

core/computed/metrics/lantern-metric.js

@@ -4,6 +4,8 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+import {LanternError} from '../../lib/lantern/lantern-error.js';
+import {LighthouseError} from '../../lib/lh-error.js';
 import {LoadSimulator} from '../load-simulator.js';
 import {PageDependencyGraph} from '../page-dependency-graph.js';
 import {ProcessedNavigation} from '../processed-navigation.js';
@@ -24,4 +26,24 @@ async function getComputationDataParams(data, context) {
   return {simulator, graph, processedNavigation};
 }
 
-export {getComputationDataParams};
+/**
+ * @param {unknown} err
+ * @return {never}
+ */
+function lanternErrorAdapter(err) {
+  if (!(err instanceof LanternError)) {
+    throw err;
+  }
+
+  const code = /** @type {keyof LighthouseError.errors} */ (err.message);
+  if (LighthouseError.errors[code]) {
+    throw new LighthouseError(LighthouseError.errors[code]);
+  }
+
+  throw err;
+}
+
+export {
+  getComputationDataParams,
+  lanternErrorAdapter,
+};

core/computed/metrics/lantern-speed-index.js

@@ -5,7 +5,7 @@
  */
 
 import {makeComputedArtifact} from '../computed-artifact.js';
-import {getComputationDataParams} from './lantern-metric.js';
+import {getComputationDataParams, lanternErrorAdapter} from './lantern-metric.js';
 import {Speedline} from '../speedline.js';
 import {LanternFirstContentfulPaint} from './lantern-first-contentful-paint.js';
 import {SpeedIndex} from '../../lib/lantern/metrics/speed-index.js';
@@ -20,7 +20,8 @@ class LanternSpeedIndex extends SpeedIndex {
    * @return {Promise<LH.Artifacts.LanternMetric>}
    */
   static async computeMetricWithGraphs(data, context, extras) {
-    return this.compute(await getComputationDataParams(data, context), extras);
+    return this.compute(await getComputationDataParams(data, context), extras)
+      .catch(lanternErrorAdapter);
   }
 
   /**

core/lib/lantern/lantern-error.js

@@ -0,0 +1,9 @@
+/**
+ * @license
+ * Copyright 2024 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+class LanternError extends Error {}
+
+export {LanternError};

core/lib/lantern/metrics/first-meaningful-paint.js

@@ -6,8 +6,6 @@
 
 import * as Lantern from '../types/lantern.js';
 import {Metric} from '../metric.js';
-// TODO(15841): don't use LighthouseError
-import {LighthouseError} from '../../lh-error.js';
 import {FirstContentfulPaint} from './first-contentful-paint.js';
 
 /** @typedef {import('../base-node.js').Node} Node */
@@ -32,7 +30,7 @@ class FirstMeaningfulPaint extends Metric {
   static getOptimisticGraph(dependencyGraph, processedNavigation) {
     const fmp = processedNavigation.timestamps.firstMeaningfulPaint;
     if (!fmp) {
-      throw new LighthouseError(LighthouseError.errors.NO_FMP);
+      throw new Error('NO_FMP');
     }
     return FirstContentfulPaint.getFirstPaintBasedGraph(dependencyGraph, {
       cutoffTimestamp: fmp,
@@ -51,7 +49,7 @@ class FirstMeaningfulPaint extends Metric {
   static getPessimisticGraph(dependencyGraph, processedNavigation) {
     const fmp = processedNavigation.timestamps.firstMeaningfulPaint;
     if (!fmp) {
-      throw new LighthouseError(LighthouseError.errors.NO_FMP);
+      throw new Error('NO_FMP');
     }
 
     return FirstContentfulPaint.getFirstPaintBasedGraph(dependencyGraph, {

core/lib/lantern/metrics/largest-contentful-paint.js

@@ -6,8 +6,8 @@
 
 import * as Lantern from '../types/lantern.js';
 import {Metric} from '../metric.js';
-import {LighthouseError} from '../../../lib/lh-error.js';
 import {FirstContentfulPaint} from './first-contentful-paint.js';
+import {LanternError} from '../lantern-error.js';
 
 /** @typedef {import('../base-node.js').Node} Node */
 
@@ -45,7 +45,7 @@ class LargestContentfulPaint extends Metric {
   static getOptimisticGraph(dependencyGraph, processedNavigation) {
     const lcp = processedNavigation.timestamps.largestContentfulPaint;
     if (!lcp) {
-      throw new LighthouseError(LighthouseError.errors.NO_LCP);
+      throw new LanternError('NO_LCP');
     }
 
     return FirstContentfulPaint.getFirstPaintBasedGraph(dependencyGraph, {
@@ -62,7 +62,7 @@ class LargestContentfulPaint extends Metric {
   static getPessimisticGraph(dependencyGraph, processedNavigation) {
     const lcp = processedNavigation.timestamps.largestContentfulPaint;
     if (!lcp) {
-      throw new LighthouseError(LighthouseError.errors.NO_LCP);
+      throw new LanternError('NO_LCP');
     }
 
     return FirstContentfulPaint.getFirstPaintBasedGraph(dependencyGraph, {

core/test/computed/metrics/largest-contentful-paint-test.js

@@ -48,14 +48,19 @@ Object {
     assert.equal(result.timestamp, 713038144775);
   });
 
-  it('should fail to compute an observed value for old trace', async () => {
-    const settings = {throttlingMethod: 'provided'};
-    const context = {settings, computedCache: new Map()};
-    const URL = getURLArtifactFromDevtoolsLog(invalidDevtoolsLog);
-    const resultPromise = LargestContentfulPaint.request(
-      {gatherContext, trace: invalidTrace, devtoolsLog: invalidDevtoolsLog, settings, URL},
-      context
-    );
-    await expect(resultPromise).rejects.toThrow('NO_LCP');
+  ['provided', 'simulate'].forEach(throttlingMethod => {
+    it(`should fail to compute a value for old trace (${throttlingMethod})`, async () => {
+      const settings = {throttlingMethod};
+      const context = {settings, computedCache: new Map()};
+      const URL = getURLArtifactFromDevtoolsLog(invalidDevtoolsLog);
+      const resultPromise = LargestContentfulPaint.request(
+        {gatherContext, trace: invalidTrace, devtoolsLog: invalidDevtoolsLog, settings, URL},
+        context
+      );
+      await expect(resultPromise).rejects.toMatchObject({
+        code: 'NO_LCP',
+        friendlyMessage: expect.toBeDisplayString(/The page did not display content.*NO_LCP/),
+      });
+    });
   });
 });