Merge branch 'refactor/ci-config-add-logical-validation' into 'master'

Pass dependencies to CI configuration nodes

## What does this MR do?

This MR makes it possible to pass dependencies to CI configuration nodes.

## What are the relevant issue numbers?

See #15060

## Does this MR meet the acceptance criteria?

- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing

See merge request !6009

11 files changed, 120 insertions, 93 deletions

diff --git a/lib/ci/gitlab_ci_yaml_processor.rb b/lib/ci/gitlab_ci_yaml_processor.rb
index e8c86349339..caa815f720f 100644
--- a/lib/ci/gitlab_ci_yaml_processor.rb
+++ b/lib/ci/gitlab_ci_yaml_processor.rb
@@ -55,12 +55,7 @@ module Ci
       {
         stage_idx: @stages.index(job[:stage]),
         stage: job[:stage],
-        ##
-        # Refactoring note:
-        #  - before script behaves differently than after script
-        #  - after script returns an array of commands
-        #  - before script should be a concatenated command
-        commands: [job[:before_script] || @before_script, job[:script]].flatten.compact.join("\n"),
+        commands: job[:commands],
         tag_list: job[:tags] || [],
         name: job[:name].to_s,
         allow_failure: job[:allow_failure] || false,
@@ -68,12 +63,12 @@ module Ci
         environment: job[:environment],
         yaml_variables: yaml_variables(name),
         options: {
-          image: job[:image] || @image,
-          services: job[:services] || @services,
+          image: job[:image],
+          services: job[:services],
           artifacts: job[:artifacts],
-          cache: job[:cache] || @cache,
+          cache: job[:cache],
           dependencies: job[:dependencies],
-          after_script: job[:after_script] || @after_script,
+          after_script: job[:after_script],
         }.compact
       }
     end
diff --git a/lib/gitlab/ci/config.rb b/lib/gitlab/ci/config.rb
index ae82c0db3f1..bbfa6cf7d05 100644
--- a/lib/gitlab/ci/config.rb
+++ b/lib/gitlab/ci/config.rb
@@ -14,7 +14,7 @@ module Gitlab
         @config = Loader.new(config).load!
 
         @global = Node::Global.new(@config)
-        @global.process!
+        @global.compose!
       end
 
       def valid?
diff --git a/lib/gitlab/ci/config/node/configurable.rb b/lib/gitlab/ci/config/node/configurable.rb
index 2de82d40c9d..6b7ab2fdaf2 100644
--- a/lib/gitlab/ci/config/node/configurable.rb
+++ b/lib/gitlab/ci/config/node/configurable.rb
@@ -23,9 +23,9 @@ module Gitlab
             end
           end
 
-          private
+          def compose!(deps = nil)
+            return unless valid?
 
-          def compose!
             self.class.nodes.each do |key, factory|
               factory
                 .value(@config[key])
@@ -33,6 +33,12 @@ module Gitlab
 
               @entries[key] = factory.create!
             end
+
+            yield if block_given?
+
+            @entries.each_value do |entry|
+              entry.compose!(deps)
+            end
           end
 
           class_methods do
diff --git a/lib/gitlab/ci/config/node/entry.rb b/lib/gitlab/ci/config/node/entry.rb
index 0c782c422b5..8717eabf81e 100644
--- a/lib/gitlab/ci/config/node/entry.rb
+++ b/lib/gitlab/ci/config/node/entry.rb
@@ -20,11 +20,14 @@ module Gitlab
             @validator.validate(:new)
           end
 
-          def process!
+          def [](key)
+            @entries[key] || Node::Undefined.new
+          end
+
+          def compose!(deps = nil)
             return unless valid?
 
-            compose!
-            descendants.each(&:process!)
+            yield if block_given?
           end
 
           def leaf?
@@ -73,11 +76,6 @@ module Gitlab
           def self.validator
             Validator
           end
-
-          private
-
-          def compose!
-          end
         end
       end
     end
diff --git a/lib/gitlab/ci/config/node/factory.rb b/lib/gitlab/ci/config/node/factory.rb
index 707b052e6a8..5387f29ad59 100644
--- a/lib/gitlab/ci/config/node/factory.rb
+++ b/lib/gitlab/ci/config/node/factory.rb
@@ -37,8 +37,8 @@ module Gitlab
             # See issue #18775.
             #
             if @value.nil?
-              Node::Undefined.new(
-                fabricate_undefined
+              Node::Unspecified.new(
+                fabricate_unspecified
               )
             else
               fabricate(@node, @value)
@@ -47,13 +47,13 @@ module Gitlab
 
           private
 
-          def fabricate_undefined
+          def fabricate_unspecified
             ##
             # If node has a default value we fabricate concrete node
             # with default value.
             #
             if @node.default.nil?
-              fabricate(Node::Null)
+              fabricate(Node::Undefined)
             else
               fabricate(@node, @node.default)
             end
diff --git a/lib/gitlab/ci/config/node/global.rb b/lib/gitlab/ci/config/node/global.rb
index ccd539fb003..2a2943c9288 100644
--- a/lib/gitlab/ci/config/node/global.rb
+++ b/lib/gitlab/ci/config/node/global.rb
@@ -36,15 +36,15 @@ module Gitlab
           helpers :before_script, :image, :services, :after_script,
                   :variables, :stages, :types, :cache, :jobs
 
-          private
-
-          def compose!
-            super
-
-            compose_jobs!
-            compose_deprecated_entries!
+          def compose!(_deps = nil)
+            super(self) do
+              compose_jobs!
+              compose_deprecated_entries!
+            end
           end
 
+          private
+
           def compose_jobs!
             factory = Node::Factory.new(Node::Jobs)
               .value(@config.except(*self.class.nodes.keys))
diff --git a/lib/gitlab/ci/config/node/job.rb b/lib/gitlab/ci/config/node/job.rb
index e84737acbb9..0cbdf7619c0 100644
--- a/lib/gitlab/ci/config/node/job.rb
+++ b/lib/gitlab/ci/config/node/job.rb
@@ -80,7 +80,19 @@ module Gitlab
 
           helpers :before_script, :script, :stage, :type, :after_script,
                   :cache, :image, :services, :only, :except, :variables,
-                  :artifacts
+                  :artifacts, :commands
+
+          def compose!(deps = nil)
+            super do
+              if type_defined? && !stage_defined?
+                @entries[:stage] = @entries[:type]
+              end
+
+              @entries.delete(:type)
+            end
+
+            inherit!(deps)
+          end
 
           def name
             @metadata[:name]
@@ -90,12 +102,30 @@ module Gitlab
             @config.merge(to_hash.compact)
           end
 
+          def commands
+            (before_script_value.to_a + script_value.to_a).join("\n")
+          end
+
           private
 
+          def inherit!(deps)
+            return unless deps
+
+            self.class.nodes.each_key do |key|
+              global_entry = deps[key]
+              job_entry = @entries[key]
+
+              if global_entry.specified? && !job_entry.specified?
+                @entries[key] = global_entry
+              end
+            end
+          end
+
           def to_hash
             { name: name,
               before_script: before_script,
               script: script,
+              commands: commands,
               image: image,
               services: services,
               stage: stage,
@@ -106,16 +136,6 @@ module Gitlab
               artifacts: artifacts,
               after_script: after_script }
           end
-
-          def compose!
-            super
-
-            if type_defined? && !stage_defined?
-              @entries[:stage] = @entries[:type]
-            end
-
-            @entries.delete(:type)
-          end
         end
       end
     end
diff --git a/lib/gitlab/ci/config/node/jobs.rb b/lib/gitlab/ci/config/node/jobs.rb
index a1a26d4fd8f..d10e80d1a7d 100644
--- a/lib/gitlab/ci/config/node/jobs.rb
+++ b/lib/gitlab/ci/config/node/jobs.rb
@@ -26,19 +26,23 @@ module Gitlab
             name.to_s.start_with?('.')
           end
 
-          private
-
-          def compose!
-            @config.each do |name, config|
-              node = hidden?(name) ? Node::Hidden : Node::Job
-
-              factory = Node::Factory.new(node)
-                .value(config || {})
-                .metadata(name: name)
-                .with(key: name, parent: self,
-                      description: "#{name} job definition.")
+          def compose!(deps = nil)
+            super do
+              @config.each do |name, config|
+                node = hidden?(name) ? Node::Hidden : Node::Job
+
+                factory = Node::Factory.new(node)
+                  .value(config || {})
+                  .metadata(name: name)
+                  .with(key: name, parent: self,
+                        description: "#{name} job definition.")
+
+                @entries[name] = factory.create!
+              end
 
-              @entries[name] = factory.create!
+              @entries.each_value do |entry|
+                entry.compose!(deps)
+              end
             end
           end
         end
diff --git a/lib/gitlab/ci/config/node/null.rb b/lib/gitlab/ci/config/node/null.rb
deleted file mode 100644
index 88a5f53f13c..00000000000
--- a/lib/gitlab/ci/config/node/null.rb
+++ /dev/null
@@ -1,34 +0,0 @@
-module Gitlab
-  module Ci
-    class Config
-      module Node
-        ##
-        # This class represents an undefined node.
-        #
-        # Implements the Null Object pattern.
-        #
-        class Null < Entry
-          def value
-            nil
-          end
-
-          def valid?
-            true
-          end
-
-          def errors
-            []
-          end
-
-          def specified?
-            false
-          end
-
-          def relevant?
-            false
-          end
-        end
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/ci/config/node/undefined.rb b/lib/gitlab/ci/config/node/undefined.rb
index 45fef8c3ae5..33e78023539 100644
--- a/lib/gitlab/ci/config/node/undefined.rb
+++ b/lib/gitlab/ci/config/node/undefined.rb
@@ -3,15 +3,34 @@ module Gitlab
     class Config
       module Node
         ##
-        # This class represents an unspecified entry node.
+        # This class represents an undefined node.
         #
-        # It decorates original entry adding method that indicates it is
-        # unspecified.
+        # Implements the Null Object pattern.
         #
-        class Undefined < SimpleDelegator
+        class Undefined < Entry
+          def initialize(*)
+            super(nil)
+          end
+
+          def value
+            nil
+          end
+
+          def valid?
+            true
+          end
+
+          def errors
+            []
+          end
+
           def specified?
             false
           end
+
+          def relevant?
+            false
+          end
         end
       end
     end
diff --git a/lib/gitlab/ci/config/node/unspecified.rb b/lib/gitlab/ci/config/node/unspecified.rb
new file mode 100644
index 00000000000..a7d1f6131b8
--- /dev/null
+++ b/lib/gitlab/ci/config/node/unspecified.rb
@@ -0,0 +1,19 @@
+module Gitlab
+  module Ci
+    class Config
+      module Node
+        ##
+        # This class represents an unspecified entry node.
+        #
+        # It decorates original entry adding method that indicates it is
+        # unspecified.
+        #
+        class Unspecified < SimpleDelegator
+          def specified?
+            false
+          end
+        end
+      end
+    end
+  end
+end