[mark-wiemer]

PR Checklist

• Addresses an existing open issue: fixes 🐛 Bug: Mocha 12 RC 6 CLI parser fails to handle negative numbers and quoted flags #6252
• That issue was marked as status: accepting prs
• Steps in CONTRIBUTING.md were taken

Overview

We naively split args on single spaces earlier, which ignored cases like quoted strings, tabs, and more.

We also rejected negative numbers and dash-prefixed option values (--grep -foo is rejected in 12 RC 6), where Mocha 11 does not reject these cases.

This PR adds a splitArgs helper to handle these cases better and the same as Mocha 11.

[codecov]

Codecov Report

❌ Patch coverage is 98.27586% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 82.12%. Comparing base (505b5e9) to head (bf03330).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/cli/parse-args.js	98.27%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6250      +/-   ##
==========================================
+ Coverage   81.93%   82.12%   +0.18%     
==========================================
  Files          64       64              
  Lines        4866     4922      +56     
  Branches     1100     1086      -14     
==========================================
+ Hits         3987     4042      +55     
- Misses        879      880       +1     

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[mark-wiemer]

Without this fix, one new test is broken, and 11 others fail. Skipping the broken should allow negative numeric values in MOCHA_OPTIONS, we get:

  1219 passing (6s)
  4 pending
  11 failing

  1) options
       loadOptions()
         env options
           should parse quoted flags from MOCHA_OPTIONS:
     UnexpectedError: 
expected
{
  _: [ 'bar\'' ], timeout: 1000, extension: [ 'js' ], grep: '\'foo',
  color: true, config: false, package: false
}
to satisfy { grep: 'foo bar', color: true }

{
  _: [ 'bar\'' ],
  timeout: 1000,
  extension: [ 'js' ],
  grep: '\'foo', // should equal 'foo bar'
                 //
                 // 'foo
                 // foo bar
  color: true,
  config: false,
  package: false
}

      at Context.<anonymous> (file:///.../test/node-unit/cli/options.spec.js:486:9)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)
      set UNEXPECTED_FULL_TRACE=true to see the full stack trace

  2) parse-args
       accepts negative numeric option values in separated form:
     Error: Not enough arguments following: timeout
      at <anonymous> (lib/cli/parse-args.js:202:13)
      at Array.forEach (<anonymous>)
      at allArgs (lib/cli/parse-args.js:193:11)
      at parseMochaArgs (lib/cli/parse-args.js:293:3)
      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:243:12)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)

  3) parse-args
       accepts negative numeric option values from strings:
     Error: Not enough arguments following: timeout
      at <anonymous> (lib/cli/parse-args.js:202:13)
      at Array.forEach (<anonymous>)
      at allArgs (lib/cli/parse-args.js:193:11)
      at parseMochaArgs (lib/cli/parse-args.js:293:3)
      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:249:12)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)

  4) parse-args
       accepts decimal and exponential negative numeric option values:
     Error: Not enough arguments following: timeout
      at <anonymous> (lib/cli/parse-args.js:202:13)
      at Array.forEach (<anonymous>)
      at allArgs (lib/cli/parse-args.js:193:11)
      at parseMochaArgs (lib/cli/parse-args.js:293:3)
      at file:///.../test/node-unit/cli/parse-args.spec.js:256:14
      at Array.forEach (<anonymous>)
      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:255:29)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)

  5) parse-args
       parses double-quoted arguments from strings:
     UnexpectedError: 
expected
{
  _: [ 'bar"' ], timeout: 1000, extension: [ 'js' ], grep: '"foo', retries: 3,
  color: true
}
to satisfy { grep: 'foo bar', retries: 3, color: true }

{
  _: [ 'bar"' ],
  timeout: 1000,
  extension: [ 'js' ],
  grep: '"foo', // should equal 'foo bar'
                //
                // "foo
                // foo bar
  retries: 3,
  color: true
}

      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:263:5)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)
      set UNEXPECTED_FULL_TRACE=true to see the full stack trace

  6) parse-args
       parses single-quoted arguments from strings:
     UnexpectedError: 
expected { _: [ 'bar\'' ], timeout: 1000, extension: [ 'js' ], grep: '\'foo', color: true }
to satisfy { grep: 'foo bar', color: true }

{
  _: [ 'bar\'' ],
  timeout: 1000,
  extension: [ 'js' ],
  grep: '\'foo', // should equal 'foo bar'
                 //
                 // 'foo
                 // foo bar
  color: true
}

      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:275:5)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)
      set UNEXPECTED_FULL_TRACE=true to see the full stack trace

  7) parse-args
       parses quoted values attached to options from strings:
     UnexpectedError: 
expected { _: [ 'bar"' ], timeout: 1000, extension: [ 'js' ], grep: '"foo' }
to satisfy { grep: 'foo bar' }

{
  _: [ 'bar"' ],
  timeout: 1000,
  extension: [ 'js' ],
  grep: '"foo' // should equal 'foo bar'
               //
               // "foo
               // foo bar
}

      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:286:5)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)
      set UNEXPECTED_FULL_TRACE=true to see the full stack trace

  8) parse-args
       preserves empty quoted option values from strings:
     UnexpectedError: 
expected { _: [], timeout: 1000, extension: [ 'js' ], grep: '""' } to satisfy { grep: '' }

{
  _: [],
  timeout: 1000,
  extension: [ 'js' ],
  grep: '""' // should equal ''
             //
             // ""
}

      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:292:5)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)
      set UNEXPECTED_FULL_TRACE=true to see the full stack trace

  9) parse-args
       parses escaped spaces and quotes from strings:
     UnexpectedError: 
expected
{
  _: [ 'bar', '\\"quote\\""' ],
  timeout: 1000,
  extension: [ 'js' ],
  grep: 'foo\\',
  fgrep: '"a'
}
to satisfy { grep: 'foo bar', fgrep: 'a "quote"' }

{
  _: [ 'bar', '\\"quote\\""' ],
  timeout: 1000,
  extension: [ 'js' ],
  grep: 'foo\\', // should equal 'foo bar'
                 //
                 // foo\
                 // foo bar
  fgrep: '"a' // should equal 'a "quote"'
              //
              // "a
              // a "quote"
}

      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:298:5)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)
      set UNEXPECTED_FULL_TRACE=true to see the full stack trace

  10) parse-args
       splits arguments on all whitespace:
     UnexpectedError: 
expected { _: [ '\t--grep\nfoo\r\n--color', '', '' ], timeout: 1000, extension: [ 'js' ] }
to satisfy { grep: 'foo', color: true }

{
  _: [ '\t--grep\nfoo\r\n--color', '', '' ],
  timeout: 1000,
  extension: [ 'js' ]
  // missing grep: 'foo'
  // missing color: true
}

      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:315:5)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)
      set UNEXPECTED_FULL_TRACE=true to see the full stack trace

  11) parse-args
       rejects unterminated quoted arguments:
     UnexpectedError: 
expected () => parseMochaArgs('--grep "foo', defaults)
to throw /Unterminated quote in arguments/
  expected function to throw
    did not throw

      at Context.<anonymous> (file:///.../test/node-unit/cli/parse-args.spec.js:326:5)
      at callFn (lib/runnable.js:360:23)
      at Test.run (lib/runnable.js:348:7)
      at Runner.runTest (lib/runner.cjs:809:10)
      at fn (lib/runner.cjs:959:12)
      at next (lib/runner.cjs:724:14)
      at fn (lib/runner.cjs:734:7)
      at next (lib/runner.cjs:595:14)
      at Immediate._onImmediate (lib/runner.cjs:702:5)
      at process.processImmediate (node:internal/timers:485:21)
      set UNEXPECTED_FULL_TRACE=true to see the full stack trace

[JoshuaKGoldberg]

This does seem like an unfortunate amount of code to take internally rather than just use something like yargs-parser 🙃. But yargs-parser is big and I couldn't find another parser that's (a) well-maintained (b) not big (c) handles the cases we need. Ah well.

LGTM! ✅