Add support for evaluating pipeline expression variables

4 files changed, 9 insertions, 4 deletions

diff --git a/lib/gitlab/ci/pipeline/expression/lexeme/equals.rb b/lib/gitlab/ci/pipeline/expression/lexeme/equals.rb
index b499d41a509..18e4db49eee 100644
--- a/lib/gitlab/ci/pipeline/expression/lexeme/equals.rb
+++ b/lib/gitlab/ci/pipeline/expression/lexeme/equals.rb
@@ -11,7 +11,7 @@ module Gitlab
               @right = right
             end
 
-            def evaluate(**variables)
+            def evaluate(variables)
               @left.evaluate(variables) == @right.evaluate(variables)
             end
 
diff --git a/lib/gitlab/ci/pipeline/expression/lexeme/null.rb b/lib/gitlab/ci/pipeline/expression/lexeme/null.rb
index 5bf06a9eee2..b62e72cde2a 100644
--- a/lib/gitlab/ci/pipeline/expression/lexeme/null.rb
+++ b/lib/gitlab/ci/pipeline/expression/lexeme/null.rb
@@ -10,9 +10,13 @@ module Gitlab
               @value = value
             end
 
-            def evaluate(**_)
+            def evaluate(_)
               nil
             end
+
+            def self.build(value)
+              new(value)
+            end
           end
         end
       end
diff --git a/lib/gitlab/ci/pipeline/expression/lexeme/string.rb b/lib/gitlab/ci/pipeline/expression/lexeme/string.rb
index 6f77d443c3c..d655b029315 100644
--- a/lib/gitlab/ci/pipeline/expression/lexeme/string.rb
+++ b/lib/gitlab/ci/pipeline/expression/lexeme/string.rb
@@ -10,7 +10,7 @@ module Gitlab
               @value = value
             end
 
-            def evaluate(**_)
+            def evaluate(_)
               @value.to_s
             end
 
diff --git a/lib/gitlab/ci/pipeline/expression/lexeme/variable.rb b/lib/gitlab/ci/pipeline/expression/lexeme/variable.rb
index 01eea6b19a6..ccf1fdfae2c 100644
--- a/lib/gitlab/ci/pipeline/expression/lexeme/variable.rb
+++ b/lib/gitlab/ci/pipeline/expression/lexeme/variable.rb
@@ -10,7 +10,8 @@ module Gitlab
               @name = name
             end
 
-            def evaluate(**variables)
+            def evaluate(variables)
+              variables[@name]
             end
 
             def self.build(string)