core(speed-index): only compute perceptual speed index

lighthouse-core/audits/speed-index-metric.js

@@ -43,7 +43,7 @@ class SpeedIndexMetric extends Audit {
         throw new Error('Trace unable to find visual progress frames.');
       }
 
-      if (speedline.speedIndex === 0) {
+      if (speedline.perceptualSpeedIndex === 0) {
         throw new Error('Error in Speedline calculating Speed Index (speedIndex of 0).');
       }
 
@@ -71,14 +71,12 @@ class SpeedIndexMetric extends Audit {
           firstVisualChange: speedline.first,
           visuallyReady: visuallyReadyInMs,
           visuallyComplete: speedline.complete,
-          speedIndex: speedline.speedIndex,
           perceptualSpeedIndex: speedline.perceptualSpeedIndex,
         },
         timestamps: {
           firstVisualChange: (speedline.first + speedline.beginning) * 1000,
           visuallyReady: (visuallyReadyInMs + speedline.beginning) * 1000,
           visuallyComplete: (speedline.complete + speedline.beginning) * 1000,
-          speedIndex: (speedline.speedIndex + speedline.beginning) * 1000,
           perceptualSpeedIndex: (speedline.perceptualSpeedIndex + speedline.beginning) * 1000,
         },
         frames: speedline.frames.map(frame => {

lighthouse-core/gather/computed/speedline.js

@@ -29,6 +29,7 @@ class Speedline extends ComputedArtifact {
       return speedline(traceEvents, {
         timeOrigin: navStart,
         fastMode: true,
+        include: 'perceptualSpeedIndex',
       });
     });
   }

lighthouse-core/test/audits/speed-index-metric-test.js

@@ -9,6 +9,8 @@
 
 const Audit = require('../../audits/speed-index-metric.js');
 const assert = require('assert');
+const pwaTrace = require('../fixtures/traces/progressive-app.json');
+const Runner = require('../../runner.js');
 
 const emptyTraceStub = {
   traces: {
@@ -34,6 +36,21 @@ describe('Performance: speed-index-metric audit', () => {
     };
   }
 
+  it('works on a real trace', () => {
+    const artifacts = Object.assign(Runner.instantiateComputedArtifacts(), {
+      traces: {defaultPass: {traceEvents: pwaTrace}},
+    });
+
+    return Audit.audit(artifacts).then(result => {
+      assert.equal(result.score, 100);
+      assert.equal(result.rawValue, 609);
+      assert.equal(Math.round(result.extendedInfo.value.timings.firstVisualChange), 475);
+      assert.equal(Math.round(result.extendedInfo.value.timings.visuallyReady), 700);
+      assert.equal(Math.round(result.extendedInfo.value.timings.visuallyComplete), 1105);
+      assert.equal(Math.round(result.extendedInfo.value.timings.perceptualSpeedIndex), 609);
+    });
+  });
+
   it('throws an error if no frames', () => {
     const artifacts = mockArtifactsWithSpeedlineResult({frames: []});
     return Audit.audit(artifacts).then(
@@ -44,7 +61,7 @@ describe('Performance: speed-index-metric audit', () => {
   it('throws an error if speed index of 0', () => {
     const SpeedlineResult = {
       frames: [frame(), frame(), frame()],
-      speedIndex: 0,
+      perceptualSpeedIndex: 0,
     };
     const artifacts = mockArtifactsWithSpeedlineResult(SpeedlineResult);
 
@@ -53,12 +70,11 @@ describe('Performance: speed-index-metric audit', () => {
       _ => assert.ok(true));
   });
 
-  it('scores speed index of 831 as 100', () => {
+  it('scores speed index of 845 as 100', () => {
     const SpeedlineResult = {
       frames: [frame(), frame(), frame()],
       first: 630,
       complete: 930,
-      speedIndex: 831,
       perceptualSpeedIndex: 845,
     };
     const artifacts = mockArtifactsWithSpeedlineResult(SpeedlineResult);
@@ -67,7 +83,6 @@ describe('Performance: speed-index-metric audit', () => {
       assert.equal(response.rawValue, 845);
       assert.equal(response.extendedInfo.value.timings.firstVisualChange, 630);
       assert.equal(response.extendedInfo.value.timings.visuallyComplete, 930);
-      assert.equal(response.extendedInfo.value.timings.speedIndex, 831);
       assert.equal(response.extendedInfo.value.timings.perceptualSpeedIndex, 845);
     });
   });

lighthouse-core/test/gather/computed/speedline-test.js

@@ -29,16 +29,17 @@ describe('Speedline gatherer', () => {
     });
   });
 
-  it('measures the pwa.rocks example with speed index of 577', () => {
+  it('measures the pwa.rocks example', () => {
     return computedArtifacts.requestSpeedline({traceEvents: pwaTrace}).then(speedline => {
-      return assert.equal(Math.floor(speedline.speedIndex), 561);
+      assert.equal(speedline.speedIndex, undefined);
+      assert.equal(Math.floor(speedline.perceptualSpeedIndex), 609);
     });
   });
 
   it('measures SI of 3 frame trace (blank @1s, content @2s, more content @3s)', () => {
     return computedArtifacts.requestSpeedline(threeFrameTrace).then(speedline => {
-      assert.equal(Math.floor(speedline.speedIndex), 2040);
-      return assert.equal(Math.floor(speedline.perceptualSpeedIndex), 2030);
+      assert.equal(speedline.speedIndex, undefined);
+      assert.equal(Math.floor(speedline.perceptualSpeedIndex), 2030);
     });
   });
 
@@ -59,7 +60,7 @@ describe('Speedline gatherer', () => {
         assert.ok(Date.now() - start < 50, 'Quick results come from the cache');
         assert.equal(firstResult, speedline, 'Cache match matches');
 
-        return assert.equal(Math.floor(speedline.speedIndex), 561);
+        return assert.equal(Math.floor(speedline.perceptualSpeedIndex), 609);
       });
   });
 

package.json

@@ -88,7 +88,7 @@
     "raven": "^2.2.1",
     "rimraf": "^2.6.1",
     "semver": "^5.3.0",
-    "speedline": "1.2.0",
+    "speedline": "1.3.0",
     "update-notifier": "^2.1.0",
     "whatwg-url": "4.0.0",
     "ws": "1.1.2",

yarn.lock

@@ -2715,7 +2715,7 @@ loose-envify@^1.0.0:
   dependencies:
     js-tokens "^1.0.1"
 
-loud-rejection@^1.0.0, loud-rejection@^1.3.0:
+loud-rejection@^1.0.0, loud-rejection@^1.6.0:
   version "1.6.0"
   resolved "https://registry.yarnpkg.com/loud-rejection/-/loud-rejection-1.6.0.tgz#5b46f80147edee578870f086d04821cf998e551f"
   dependencies:
@@ -3694,14 +3694,14 @@ spdx-license-ids@^1.0.2:
   version "1.2.2"
   resolved "https://registry.yarnpkg.com/spdx-license-ids/-/spdx-license-ids-1.2.2.tgz#c9df7a3424594ade6bd11900d596696dc06bac57"
 
-speedline@1.2.0:
-  version "1.2.0"
-  resolved "https://registry.yarnpkg.com/speedline/-/speedline-1.2.0.tgz#f5828dcf8e9b96a9f6c1da8ab298538820c6668d"
+speedline@1.3.0:
+  version "1.3.0"
+  resolved "https://registry.yarnpkg.com/speedline/-/speedline-1.3.0.tgz#201c458ca7aba2ac847fe5860c1a92966aaed3a9"
   dependencies:
     babar "0.0.3"
     image-ssim "^0.2.0"
     jpeg-js "^0.1.2"
-    loud-rejection "^1.3.0"
+    loud-rejection "^1.6.0"
     meow "^3.7.0"
 
 split2@^2.0.0: