evs@evs-precision3590:~/sites/spec2 $ c283 require --dev phpunit/phpunit:^10
Composer could not detect the root package (root/spec2) version, defaulting to '1.0.0'. See https://getcomposer.org/root-version
./composer.json has been updated
Composer could not detect the root package (root/spec2) version, defaulting to '1.0.0'. See https://getcomposer.org/root-version
Running composer update phpunit/phpunit
Loading composer repositories with package information
Updating dependencies                                 
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Root composer.json requires phpunit/phpunit ^10 -> satisfiable by phpunit/phpunit[10.0.0, ..., 10.5.38].
    - phpunit/phpunit[10.0.0, ..., 10.5.26] require sebastian/comparator ^5.0 -> found sebastian/comparator[5.0.0, 5.0.1, 5.0.2, 5.0.3] but the package is fixed to 6.2.1 (lock file version) by a partial update and that version does not match. Make sure you list it as an argument for the update command.
    - phpunit/phpunit[10.5.27, ..., 10.5.29] require sebastian/comparator ^5.0.1 -> found sebastian/comparator[5.0.1, 5.0.2, 5.0.3] but the package is fixed to 6.2.1 (lock file version) by a partial update and that version does not match. Make sure you list it as an argument for the update command.
    - phpunit/phpunit[10.5.30, ..., 10.5.36] require sebastian/comparator ^5.0.2 -> found sebastian/comparator[5.0.2, 5.0.3] but the package is fixed to 6.2.1 (lock file version) by a partial update and that version does not match. Make sure you list it as an argument for the update command.
    - phpunit/phpunit[10.5.37, ..., 10.5.38] require sebastian/comparator ^5.0.3 -> found sebastian/comparator[5.0.3] but the package is fixed to 6.2.1 (lock file version) by a partial update and that version does not match. Make sure you list it as an argument for the update command.

Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.

Installation failed, reverting ./composer.json and ./composer.lock to their original content.
evs@evs-precision3590:~/sites/spec2 $ c283 require --dev phpunit/phpunit:^10 -w
Composer could not detect the root package (root/spec2) version, defaulting to '1.0.0'. See https://getcomposer.org/root-version
./composer.json has been updated
Composer could not detect the root package (root/spec2) version, defaulting to '1.0.0'. See https://getcomposer.org/root-version
Running composer update phpunit/phpunit --with-dependencies
Loading composer repositories with package information
Updating dependencies                                 
Lock file operations: 22 installs, 4 updates, 0 removals
  - Locking myclabs/deep-copy (1.12.1)
  - Locking nikic/php-parser (v5.3.1)
  - Locking phar-io/manifest (2.0.4)
  - Locking phar-io/version (3.2.1)
  - Locking phpunit/php-code-coverage (10.1.16)
  - Locking phpunit/php-file-iterator (4.1.0)
  - Locking phpunit/php-invoker (4.0.0)
  - Locking phpunit/php-text-template (3.0.1)
  - Locking phpunit/php-timer (6.0.0)
  - Locking phpunit/phpunit (10.5.38)
  - Locking sebastian/cli-parser (2.0.1)
  - Locking sebastian/code-unit (2.0.0)
  - Locking sebastian/code-unit-reverse-lookup (3.0.0)
  - Downgrading sebastian/comparator (6.2.1 => 5.0.3)
  - Locking sebastian/complexity (3.2.0)
  - Downgrading sebastian/diff (6.0.2 => 5.1.1)
  - Locking sebastian/environment (6.1.0)
  - Downgrading sebastian/exporter (6.1.3 => 5.1.2)
  - Locking sebastian/global-state (6.0.2)
  - Locking sebastian/lines-of-code (2.0.2)
  - Locking sebastian/object-enumerator (5.0.0)
  - Locking sebastian/object-reflector (3.0.0)
  - Downgrading sebastian/recursion-context (6.0.2 => 5.0.0)
  - Locking sebastian/type (4.0.0)
  - Locking sebastian/version (4.0.1)
  - Locking theseer/tokenizer (1.2.3)
Writing lock file
Installing dependencies from lock file (including require-dev)
Package operations: 22 installs, 4 updates, 0 removals
  - Downgrading sebastian/recursion-context (6.0.2 => 5.0.0): Extracting archive
  - Downgrading sebastian/exporter (6.1.3 => 5.1.2): Extracting archive
  - Downgrading sebastian/diff (6.0.2 => 5.1.1): Extracting archive
  - Downgrading sebastian/comparator (6.2.1 => 5.0.3): Extracting archive
  - Installing sebastian/version (4.0.1): Extracting archive
  - Installing sebastian/type (4.0.0): Extracting archive
  - Installing sebastian/object-reflector (3.0.0): Extracting archive
  - Installing sebastian/object-enumerator (5.0.0): Extracting archive
  - Installing sebastian/global-state (6.0.2): Extracting archive
  - Installing sebastian/environment (6.1.0): Extracting archive
  - Installing sebastian/code-unit (2.0.0): Extracting archive
  - Installing sebastian/cli-parser (2.0.1): Extracting archive
  - Installing phpunit/php-timer (6.0.0): Extracting archive
  - Installing phpunit/php-text-template (3.0.1): Extracting archive
  - Installing phpunit/php-invoker (4.0.0): Extracting archive
  - Installing phpunit/php-file-iterator (4.1.0): Extracting archive
  - Installing theseer/tokenizer (1.2.3): Extracting archive
  - Installing nikic/php-parser (v5.3.1): Extracting archive
  - Installing sebastian/lines-of-code (2.0.2): Extracting archive
  - Installing sebastian/complexity (3.2.0): Extracting archive
  - Installing sebastian/code-unit-reverse-lookup (3.0.0): Extracting archive
  - Installing phpunit/php-code-coverage (10.1.16): Extracting archive
  - Installing phar-io/version (3.2.1): Extracting archive
  - Installing phar-io/manifest (2.0.4): Extracting archive
  - Installing myclabs/deep-copy (1.12.1): Extracting archive
  - Installing phpunit/phpunit (10.5.38): Extracting archive
1 package suggestions were added by new dependencies, use `composer suggest` to see details.
Generating autoload files
38 packages you are using are looking for funding.
Use the `composer fund` command to find out more!
No security vulnerability advisories found.