Bug in @bcoe/v8-coverage: undefined is not iterable

[sebbo2002]

• Version: v18.20.4 and v20.12.2
• Platform: Darwin 23.6.0 Kernel Version 23.6.0 / GitHub Runner Ubuntu 22.0.4 LTS

There seems to be a bug in @bcoe/v8-coverage that I am currently struggling with in this repository.
I get the following error at the end of the test:

TypeError: undefined is not iterable (cannot read property Symbol(Symbol.iterator))
    at RangeTree.fromSortedRanges (/home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/range-tree.js:27:39)
    at normalizeFunctionCov (/home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/normalize.js:74:41)
    at Object.deepNormalizeScriptCov (/home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/normalize.js:59:9)
    at mergeScriptCovs (/home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/merge.js:59:21)
    at mergeProcessCovs (/home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/merge.js:34:21)
    at Report._getMergedProcessCov (/home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/c8/lib/report.js:336:12)
    at Report.getCoverageMapFromAllCoverageFiles (/home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/c8/lib/report.js:245:27)
    at Report.run (/home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/c8/lib/report.js:84:31)
    at exports.outputReport (/home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/c8/lib/commands/report.js:42:16)
    at /home/runner/work/vestaboard2mqtt/vestaboard2mqtt/node_modules/c8/bin/c8.js:30:15

There is already a pull request for this in the forked repository. This pull request solves the problem for me. Would it be possible to merge this patch into @bcoe/v8-coverage and use this new version to fix the bug? Thank you very much.

[cenfun]

Try c8 --experimental-monocart mocha to see if the error still exists

[sebbo2002]

After running npm i monocart-coverage-reports@2 --save-dev it works fine, yes.

~/C/vestaboard2mqtt ❯❯❯ npm run coverage

> @sebbo2002/vestaboard2mqtt@1.0.0-test.0 coverage
> c8 mocha



  Cache
    set() / get() / delete()
      ✔ should work

  Calendar
    isSameDay()
      ✔ should work (1)
      ✔ should work (2)

  Message
    write()
      ✔ should start writing from top/left
      ✔ should accept line & row for positioning
      ✔ should add another line if text is too long
      ✔ should work with words > board length
      ✔ should allow to use CURRENT and NEXT line flags
      ✔ should remove unsupported words
    repeat()
      ✔ should work
    word2char()
      ✔ should work
      ✔ should handle german Umlaute
      ✔ should handle color emojis
      ✔ should remove special chars
    centerLines()
      ✔ should work
    center()
      ✔ should work
    isEmpty()
      ✔ should work
    toString()
      ✔ should work with empty board
      ✔ should work with any supported char


  19 passing (22ms)

TypeError: undefined is not iterable (cannot read property Symbol(Symbol.iterator))
    at RangeTree.fromSortedRanges (/Users/sebbo/Code/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/range-tree.js:27:39)
    at normalizeFunctionCov (/Users/sebbo/Code/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/normalize.js:74:41)
    at Object.deepNormalizeScriptCov (/Users/sebbo/Code/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/normalize.js:59:9)
    at mergeScriptCovs (/Users/sebbo/Code/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/merge.js:59:21)
    at mergeProcessCovs (/Users/sebbo/Code/vestaboard2mqtt/node_modules/@bcoe/v8-coverage/dist/lib/merge.js:34:21)
    at Report._getMergedProcessCov (/Users/sebbo/Code/vestaboard2mqtt/node_modules/c8/lib/report.js:336:12)
    at Report.getCoverageMapFromAllCoverageFiles (/Users/sebbo/Code/vestaboard2mqtt/node_modules/c8/lib/report.js:245:27)
    at Report.run (/Users/sebbo/Code/vestaboard2mqtt/node_modules/c8/lib/report.js:84:31)
    at exports.outputReport (/Users/sebbo/Code/vestaboard2mqtt/node_modules/c8/lib/commands/report.js:42:16)
    at /Users/sebbo/Code/vestaboard2mqtt/node_modules/c8/bin/c8.js:30:15
~/C/vestaboard2mqtt ❯❯❯ npx c8 --experimental-monocart mocha                                                                                                       ✘ 1 


  Cache
    set() / get() / delete()
      ✔ should work

  Calendar
    isSameDay()
      ✔ should work (1)
      ✔ should work (2)

  Message
    write()
      ✔ should start writing from top/left
      ✔ should accept line & row for positioning
      ✔ should add another line if text is too long
      ✔ should work with words > board length
      ✔ should allow to use CURRENT and NEXT line flags
      ✔ should remove unsupported words
    repeat()
      ✔ should work
    word2char()
      ✔ should work
      ✔ should handle german Umlaute
      ✔ should handle color emojis
      ✔ should remove special chars
    centerLines()
      ✔ should work
    center()
      ✔ should work
    isEmpty()
      ✔ should work
    toString()
      ✔ should work with empty board
      ✔ should work with any supported char


  19 passing (20ms)

--experimental-monocart requires the plugin monocart-coverage-reports. Run: "npm i monocart-coverage-reports@2 --save-dev"
~/C/vestaboard2mqtt ❯❯❯ npm i monocart-coverage-reports@2 --save-dev                                                                                               ✘ 1 

added 8 packages, and changed 3 packages in 2s

173 packages are looking for funding
  run `npm fund` for details
~/C/vestaboard2mqtt ❯❯❯ npx c8 --experimental-monocart mocha


  Cache
    set() / get() / delete()
      ✔ should work

  Calendar
    isSameDay()
      ✔ should work (1)
      ✔ should work (2)

  Message
    write()
      ✔ should start writing from top/left
      ✔ should accept line & row for positioning
      ✔ should add another line if text is too long
      ✔ should work with words > board length
      ✔ should allow to use CURRENT and NEXT line flags
      ✔ should remove unsupported words
    repeat()
      ✔ should work
    word2char()
      ✔ should work
      ✔ should handle german Umlaute
      ✔ should handle color emojis
      ✔ should remove special chars
    centerLines()
      ✔ should work
    center()
      ✔ should work
    isEmpty()
      ✔ should work
    toString()
      ✔ should work with empty board
      ✔ should work with any supported char


  19 passing (21ms)

------------|---------|----------|---------|---------|---------------------------
File        | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s         
------------|---------|----------|---------|---------|---------------------------
All files   |   78.51 |    85.58 |   83.33 |   78.57 |                           
 cache.ts   |   58.62 |    62.96 |   83.33 |      68 | 15,35-42,67,84-94,103-113 
 config.ts  |    12.5 |      100 |    12.5 |    12.5 | 30-72                     
 index.ts   |       0 |        0 |       0 |       0 |                           
 message.ts |   91.56 |    92.68 |   97.43 |   90.62 | 94,114,206,244,254,304    
 page.ts    |     100 |      100 |     100 |     100 |                           
------------|---------|----------|---------|---------|---------------------------

=============================== Coverage summary ===============================
Statements   : 78.51% ( 95/121 )
Branches     : 85.58% ( 95/111 )
Functions    : 83.33% ( 50/60 )
Lines        : 78.57% ( 77/98 )
================================================================================
~/C/vestaboard2mqtt ❯❯❯ 

[cenfun]

BTW, the PR is here

[sebbo2002]

@cenfun Ah thanks, I hadn't found that one. Then I can close this ticket here, right?

[cenfun]

Yes, it should be fixed in v8-coverage not c8