project.yml modules.enable/disable empty sets overridden on BLT upgrade

[geerlingguy]

My system information:

• Operating system type: macOS
• Operating system version: 10.12.2
• BLT version: 8.6.6

When I run this command:

composer update acquia/blt --with-dependencies
git diff

I get the following:

diff --git a/blt/project.yml b/blt/project.yml
index c7a481a..bc5036c 100644
--- a/blt/project.yml
+++ b/blt/project.yml
@@ -33,20 +33,20 @@ target-hooks:
 import: '${repo.root}/blt/build.xml'
 modules:
   local:
-    enable: {  }
-    uninstall: {  }
+    enable: [dblog, devel, seckit, views_ui]
+    uninstall: [acsf, acquia_connector, shield]
   ci:
     enable: {  }
-    uninstall: {  }
+    uninstall: [acquia_connector, shield]
   dev:
-    enable: {  }
+    enable: [acquia_connector, shield]
     uninstall: {  }
   test:
-    enable: {  }
-    uninstall: {  }
+    enable: [acquia_connector, shield]
+    uninstall: [devel, views_ui]
   prod:
-    enable: {  }
-    uninstall: {  }
+    enable: [acquia_connector, shield]
+    uninstall: [devel, views_ui]
   deploy:
     enable: {  }
     uninstall: {  }

And I expected this to happen:

• My custom module lists (which were set to empty since I'm using Configuration Split and manage module activation per-environment via Drupal environment-specific configuration) should not be affected by a BLT upgrade.

[grasmash]

Actually, I think this is resolved by #891, but it hasn't been released yet.

[geerlingguy]

@grasmash - on another project, after updating from 8.6.6 to 8.6.10, I got the following change (for a non-empty value) too:

diff --git a/blt/project.yml b/blt/project.yml
index c3eba8b0..b5054660 100644
--- a/blt/project.yml
+++ b/blt/project.yml
@@ -39,10 +39,10 @@ import: '${repo.root}/blt/build.xml'
 modules:
   local:
     enable: [dblog, devel, features_ui, field_ui, seckit, update, views_ui]
-    uninstall: [shield]
+    uninstall: [shield, acquia_connector, shield]

So it might not just affect empty values :/