Cannot install drush for Drupal 8.4

[mh35]

I installed Drupal 8.4, but Composer said an error as below.

./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

Problem 1
- drush/drush 8.1.0 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.1 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.2 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.3 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.4 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.5 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.6 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.7 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.8 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.9 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- Conclusion: don't install drush/drush 8.1.14
- Conclusion: don't install drush/drush 8.1.13
- Conclusion: don't install drush/drush 8.1.12
- Conclusion: don't install drush/drush 8.1.11
- Conclusion: don't install drush/drush 8.1.10
- Conclusion: don't install drush/drush 8.x-dev
- Installation request for drupal/drupal No version set (parsed as 1.0.0) -> satisfiable by drupal/drupal[No version set (parsed as 1.0.0)].
- Conclusion: remove symfony/console v3.2.8
- Installation request for symfony/dependency-injection (locked at v3.2.8, required as ~3.2.8) -> satisfiable by symfony/dependency-injection[v3.2.8].
- Installation request for drush/drush ^8.1 -> satisfiable by drush/drush[8.1.0, 8.1.1, 8.1.10, 8.1.11, 8.1.12, 8.1.13, 8.1.14, 8.1.2, 8.1.3, 8.1.4, 8.1.5, 8.1.6, 8.1.7, 8.1.8, 8.1.9, 8.8.x-dev, 8.x-dev].
- Conclusion: don't install symfony/console v3.2.8
- drush/drush 8.8.x-dev requires symfony/console ~2.7 -> satisfiable by symfony/console[2.7.x-dev, 2.8.x-dev].
- Can only install one of: symfony/console[2.7.x-dev, v3.2.8].
- Can only install one of: symfony/console[2.8.x-dev, v3.2.8].
- Installation request for symfony/console (locked at v3.2.8, required as ~3.2.8) -> satisfiable by symfony/console[v3.2.8].

Installation failed, reverting ./composer.json to its original content.

Maybe Drush has some dependency conflicts, so please check them.

[greg-1-anderson]

Try installing with 8.x-dev. We will tag a 8.1.15 release to fix this; would be helpful if some folks would help test.

[Matombo]

installing 8.x-dev fails too

$ composer require drush/drush 8.x-dev
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - Installation request for drush/drush 8.x-dev -> satisfiable by drush/drush[8.x-dev].
    - Conclusion: remove symfony/dependency-injection v3.2.8
    - Conclusion: don't install symfony/dependency-injection v3.2.8
    - drush/drush 8.x-dev requires symfony/yaml ~2.3 -> satisfiable by symfony/yaml[2.3.x-dev, 2.4.x-dev, 2.5.x-dev, 2.6.x-dev, 2.7.x-dev, 2.8.x-dev].
    - symfony/yaml 2.3.x-dev conflicts with symfony/dependency-injection[v3.2.8].
    - symfony/yaml 2.4.x-dev conflicts with symfony/dependency-injection[v3.2.8].
    - symfony/yaml 2.5.x-dev conflicts with symfony/dependency-injection[v3.2.8].
    - symfony/yaml 2.6.x-dev conflicts with symfony/dependency-injection[v3.2.8].
    - symfony/yaml 2.7.x-dev conflicts with symfony/dependency-injection[v3.2.8].
    - symfony/yaml 2.8.x-dev conflicts with symfony/dependency-injection[v3.2.8].
    - Installation request for symfony/dependency-injection (locked at v3.2.8, required as ~3.2.8) -> satisfiable by symfony/dependency-injection[v3.2.8].


Installation failed, reverting ./composer.json to its original content.

[greg-1-anderson]

Looks like we need to let the version of symfony/yml float now too.

[ergophobe]

Same issue. I had installed Drush 8.1.14 as mentioned in the Drupal 8.4 release docs, but that did not work because of the dependency conflicts mentioned above.

I installed Drush 9.x and that was fine.

Er... fine for Drupal 8.4. The drush install had issues, but that's a separate concern.

So what I meant to say by "fine" was it solved the dependency problem once I explicitly asked for compatible versions of symfony, drush and Drupal:

composer update --with-dependencies symfony/class-loader:~3.2.8 drupal/core:~8.4 drush/drush:~9.@dev

[greg-1-anderson]

I made another change to the composer.json file in the Drush 8.x dev branch, and after that was able to composer install Drupal 8.4.0 with Drush 8.x-dev.

[grasmash]

I was also able to: acquia/blt#2107

[ultimike]

I'm still unable to install Drush with Drupal core 8.4.0. Here's what I've done...

1. I was at Drupal core 8.3.7 and Drush 8.1.12.
2. I initially tried to do a composer update drupal/core --with-dependencies and was denied due to the previously well documented conflicts/changes symfony component version updates.
3. I then removed Drush using composer remove drush/drush
4. I tried updating Drupal core using Composer again, but kept getting conflicts. On a suggestion from @greg-1-anderson in Slack (thanks!) I deleted my composer.lock and entire /vendor directory and did a composer update (proceed with caution!) - this successfully updated Drupal core to 8.4.
5. Again, on a suggestion from @greg-1-anderson I waited a few days to try to reinstall Drush - he indicated he was working on a new Drush release to help solve the issue.
6. This morning, I tried composer require drush/drush --prefer-dist - I received the Your requirements could not be resolved to an installable set of packages. message (it was clear Composer was only trying to install an 8.x version of Drush).
7. I then tried composer require drush/drush:9.x --prefer-dist - I received the same message, but with different conflicts.
8. Based on the above thread, I tried composer require drush/drush:8.x-dev - still no luck. Screenshot attached.

Not sure how to proceed at this point...

thanks,
-mike

[greg-1-anderson]

reflection-dockblock can be a problem. We only support version 2 and 3 in annotated command. I want to stop using this component in Drush & c. completely.

Try composer why phpdocumentor/reflection-docblock. You might be successful if you uninstall the component that depends on that, then install Drush, then put back the other component.

We'll work on making this better.

[ultimike]

@greg-1-anderson thanks for the info.

I tracked the phpdocumentor/reflection-docblock dependency to phpunit/phpunit. I tried running composer update phpunit/phpunit --with-dependencies, but no update was available.

So, I did a composer remove phpunit/phpunit (I'm not using it) and then tried installing Drush via composer require drush/drush:8.x-dev - with success! One thing I did notice is that when I removed phpunit, it also (correctly) removed phpdocumentor/reflection-docblock version 4.1.1 and then when I installed drush/drush, it added phpdocumentor/reflection-docblock version 2.0.5.

I then tested my local by running a few drush commands and all appears to be working (phew!)

Next, I tried re-adding phpunit/phpunit with composer require phpunit/phpunit --dev --prefer-dist and it appears that version 6.4.1 was installed (I believe the previous version was 4.something - will this be an issue?)

So, at this point, I think all is well. Should I be on the lookout for a Drush 8.x or 9.x release to update to?

thanks,
-mike

[grasmash]

Try composer require drush/drush:8.x-dev --no-update && composer update.

As @greg-1-anderson indicated with his suggestion to remove composer.lock and vendor, composer update vendor/package --with-dependencies can be insufficient.

[ergophobe]

@greg-1-anderson: "We only support version 2 and 3 in annotated command"

Actually, I ran into the reflection-docblock issues as well and noticed that in fact in phpunit and annotated-command it allows:

"phpdocumentor/reflection-docblock": "^2.0|^3.0.2|^4.0"

Only the direct dependency on reflection-docblock in drush is defined as
"phpdocumentor/reflection-docblock": "^2.0"

This actually resulted in a couple more rounds of remove/require/update to deal with, but if drush had the same dependency definintion as annotated-command and phpunit, this would have worked for me with a lot less hassle.

I didn't mention it above because I wanted to run a test first to see whether reflection-docblock 4 worked with drush. If it does, could we just have the same requirements across the board?

@ultimike - that's basically what I did except

• delete composer.lock, /vendor and /web/core
• remove drush/drush and drupal/console
• run a composer update specifying versions of symfony, drupal and drush
• allow dev versions of drush (your version constraint of "9.x" would not allow dev versions I'm fairly sure - see https://getcomposer.org/doc/articles/versions.md#stability-constraints )

After this: composer update --with-dependencies symfony/class-loader:~3.2.8 drupal/core:~8.4 drush/drush:~9.@dev

Everything worked except drush which needed the patch 494f11a from #2912

I think I went overboard in terms of what I was deleting and removing, but was trying to get unstuck.

My issue with reflection-docblock started because at one point I tried composer update --with-dependencies which moved all sorts of things to the highest allowed versions at the time (and without drush required, that meant 4.x)

[MPParsley]

In my case another project had locked a too high version of phpdocumentor/reflection-docblock but drush ~8.1.12 only accepts ~2.0.0
- Installation request for phpdocumentor/reflection-docblock (locked at 3.2.2) -> satisfiable by phpdocumentor/reflection-docblock[3.2.2].

Fixed with:

• composer require phpdocumentor/reflection-docblock:~2.0.0
• composer require drush/drush:~8.1.12 --dev

[Matombo]

Similar issue with drupal 8.4.1:

$ composer require drush/drush
Using version ^8.1 for drush/drush
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

Problem 1
- drush/drush 8.1.0 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.1 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.2 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.3 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.4 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.5 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.6 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.7 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.8 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- drush/drush 8.1.9 conflicts with drupal/drupal[No version set (parsed as 1.0.0)].
- Conclusion: don't install drush/drush 8.1.15
- Conclusion: don't install drush/drush 8.1.14
- Conclusion: don't install drush/drush 8.1.13
- Conclusion: don't install drush/drush 8.1.12
- Conclusion: don't install drush/drush 8.1.11
- Conclusion: don't install drush/drush 8.1.10
- Conclusion: don't install drush/drush 8.x-dev
- Installation request for drupal/drupal No version set (parsed as 1.0.0) -> satisfiable by drupal/drupal[No version set (parsed as 1.0.0)].
- Conclusion: remove symfony/console v3.2.13
- Installation request for phpdocumentor/reflection-docblock (locked at 4.1.1) -> satisfiable by phpdocumentor/reflection-docblock[4.1.1].
- Installation request for drush/drush ^8.1 -> satisfiable by drush/drush[8.1.0, 8.1.1, 8.1.10, 8.1.11, 8.1.12, 8.1.13, 8.1.14, 8.1.15, 8.1.2, 8.1.3, 8.1.4, 8.1.5, 8.1.6, 8.1.7, 8.1.8, 8.1.9, 8.8.x-dev, 8.x-dev].
- Conclusion: don't install symfony/console v3.2.13
- drush/drush 8.8.x-dev requires symfony/console ~2.7 -> satisfiable by symfony/console[2.7.x-dev, 2.8.x-dev].
- Can only install one of: symfony/console[2.7.x-dev, v3.2.13].
- Can only install one of: symfony/console[2.8.x-dev, v3.2.13].
- Installation request for symfony/console (locked at v3.2.13, required as ~3.2.8) -> satisfiable by symfony/console[v3.2.13].

$ composer require drush/drush 8.x-dev
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

Problem 1
- Installation request for drush/drush 8.x-dev -> satisfiable by drush/drush[8.x-dev].
- Conclusion: remove phpdocumentor/reflection-docblock 4.1.1
- Conclusion: don't install phpdocumentor/reflection-docblock 4.1.1
- drush/drush 8.x-dev requires phpdocumentor/reflection-docblock ^2.0 -> satisfiable by phpdocumentor/reflection-docblock[2.0.0, 2.0.0a1, 2.0.0a2, 2.0.0a3, 2.0.1, 2.0.2, 2.0.3, 2.0.4, 2.0.5].
- Can only install one of: phpdocumentor/reflection-docblock[2.0.0, 4.1.1].
- Can only install one of: phpdocumentor/reflection-docblock[2.0.0a1, 4.1.1].
- Can only install one of: phpdocumentor/reflection-docblock[2.0.0a2, 4.1.1].
- Can only install one of: phpdocumentor/reflection-docblock[2.0.0a3, 4.1.1].
- Can only install one of: phpdocumentor/reflection-docblock[2.0.1, 4.1.1].
- Can only install one of: phpdocumentor/reflection-docblock[2.0.2, 4.1.1].
- Can only install one of: phpdocumentor/reflection-docblock[2.0.3, 4.1.1].
- Can only install one of: phpdocumentor/reflection-docblock[2.0.4, 4.1.1].
- Can only install one of: phpdocumentor/reflection-docblock[2.0.5, 4.1.1].
- Installation request for phpdocumentor/reflection-docblock (locked at 4.1.1) -> satisfiable by phpdocumentor/reflection-docblock[4.1.1].

[greg-1-anderson]

Try again with 8.x-dev now that #3157 has been merged. If that works, we can make a new tagged release.

If that does not work, try removing composer.lock and vendor and try again with 8.x-dev.

[Matombo]

it works, thanks