4.3.1

[connorjclark]

v4 branch is currently identical to tag v4.3.0

This PR proposes adding these cherrypicks to the v4 branch:

#7122
#8294
#8338
#8354
#8387

No merge conflicts :)

Fixes #8447

[connorjclark]

should be g2g, if tests pass.

[paulirish]

1 smoketest failure

node lighthouse-cli/index.js http://localhost:10200/byte-efficiency/tester.html --config-path=/home/travis/build/GoogleChrome/lighthouse/lighthouse-cli/test/smokehouse/byte-config.js --output-path=smokehouse-37174.report.json --output=json --quiet --port=0 
Asserting expected results match those found. (http://localhost:10200/byte-efficiency/tester.html)
  ✘ difference at unused-javascript.details.overallSavingsBytes
              expected: ">=25000"
                 found: 21018
          found result:

      {
        "id": "unused-javascript",
        "title": "Remove unused JavaScript",
        "description": "Remove unused JavaScript to reduce bytes consumed by network activity.",
        "score": 0.67,
        "scoreDisplayMode": "numeric",
        "rawValue": 450,
        "displayValue": "Potential savings of 21 KB",
        "details": {
          "type": "opportunity",
          "headings": [
            {
              "key": "url",
              "valueType": "url",
              "label": "URL"
            },
            {
              "key": "totalBytes",
              "valueType": "bytes",
              "label": "Size (KB)"
            },
            {
              "key": "wastedBytes",
              "valueType": "bytes",
              "label": "Potential Savings (KB)"
            }
          ],
          "items": [
            {
              "url": "http://localhost:10200/byte-efficiency/script.js",
              "totalBytes": 53181,
              "wastedBytes": 14415,
              "wastedPercent": 27.105307847614018
            },
            {
              "url": "http://localhost:10200/byte-efficiency/tester.html",
              "totalBytes": 15089,
              "wastedBytes": 6603,
              "wastedPercent": 43.76043266341724
            }
          ],
          "overallSavingsMs": 450,
          "overallSavingsBytes": 21018
        }
      }

[patrickhulce]

That failure looks suspiciously like that chrome bug from forever ago it didn't make it to stable, right?

the backports doesn't have our chrome version printing in travis so hard to tell :)

[connorjclark]

That failure looks suspiciously like that chrome bug from forever ago it didn't make it to stable, right?

#7065 (comment)
yup exactly the same

[connorjclark]

but the repro doesnt happen for me in stable ( https://bugs.chromium.org/p/chromium/issues/detail?id=927464 )

so that must mean travis is NOT using stable chrome ..

[connorjclark]

pushed a commit to print the chrome version in travis.

Google Chrome 74.0.3729.131. Which is indeed stable..

Could the smokes somehow be using a Chrome other than the one defined by:

export CHROME_PATH="$(which google-chrome-stable)"

?

[connorjclark]

coverage (in stable) for the failing bytes tester.html fixture:

lgtm

[connorjclark]

I'm 99% convinced Travis is using an old, broken Canary.

[connorjclark]

diff --git a/lighthouse-core/audits/byte-efficiency/unused-javascript.js b/lighthouse-core/audits/byte-efficiency/unused-javascript.js
index f13e0272..2d6e33a7 100644
--- a/lighthouse-core/audits/byte-efficiency/unused-javascript.js
+++ b/lighthouse-core/audits/byte-efficiency/unused-javascript.js
@@ -50,11 +50,14 @@ class UnusedJavaScript extends ByteEfficiencyAudit {
     const unusedByIndex = new Uint8Array(maximumEndOffset);
     for (const func of script.functions) {
       for (const range of func.ranges) {
+        let c = 0;
         if (range.count === 0) {
           for (let i = range.startOffset; i < range.endOffset; i++) {
             unusedByIndex[i] = 1;
+            c++;
           }
         }
+        console.log(func.functionName, range.count, c);
       }
     }

  status Evaluating: Remove unused JavaScript +3ms
 1 0
generateInlineStyleWithSize 1 0
longTask 1 0
 1 0
 1 0
 1 0
 1 0
 1 0
unusedFunction 0 6554
 1 0
anUnusedFunction 0 14365
aUsedFunction 1 0

notice aNestedUnusedFunction is missing, which accounts for 7875 missed unused bytes.

[connorjclark]

running master LH:

 1 0
generateInlineStyleWithSize 1 0
longTask 1 0
 1 0
 1 0
 1 0
 1 0
 1 0
unusedFunction 0 6554
 1 0
anUnusedFunction 0 14365
aUsedFunction 1 0
aNestedUnusedFunction 0 7875 <<<<<<<<<<<<<

hmmm....

no diff in the script.js / audit between master/v430 .

[connorjclark]

We gonna just change the smoke test value to pass. The unused-javascript audit is not in default config and won't ever run in DT (which will be shipped with 4.3.1 for a while).

There may be some sort of big to file upstream but it won't affect LH since the async stacks PR does something to fix things.

As for why the errors smoke test fails ... It works locally, maybe it's just flaky. Let's try again.