fix(stageExecution): In evaluable variable stage restart scenario var…

…iables are not cleaned properly (#16) (backport #4307) (#4327)

Co-authored-by: Oscar Michel Herrera <oscarmichelh@gmail.com>

orca-core/src/main/java/com/netflix/spinnaker/orca/pipeline/EvaluateVariablesStage.java

@@ -49,6 +49,22 @@ public void taskGraph(@Nonnull StageExecution stage, @Nonnull TaskNode.Builder b
     builder.withTask("evaluateVariables", EvaluateVariablesTask.class);
   }
 
+  @Override
+  public void prepareStageForRestart(@Nonnull StageExecution stage) {
+    stage.getOutputs().clear();
+    EvaluateVariablesStageContext context = stage.mapTo(EvaluateVariablesStageContext.class);
+
+    List<Variable> variables =
+        Optional.ofNullable(context.getVariables()).orElse(Collections.emptyList());
+    for (Variable var : variables) {
+      if (var.sourceExpression instanceof String) {
+        var.value = var.sourceExpression.toString().replace("{", "${");
+        var.sourceExpression = null;
+      }
+    }
+    stage.getContext().put("variables", variables);
+  }
+
   @Override
   public boolean processExpressions(
       @Nonnull StageExecution stage,

orca-core/src/test/groovy/com/netflix/spinnaker/orca/pipeline/tasks/EvaluateVariablesStageSpec.groovy

@@ -81,4 +81,29 @@ class EvaluateVariablesStageSpec extends Specification {
     shouldContinue == false
     stage.context.notifications[0].address == "someone@somewhere.com"
   }
+
+  void "Should correctly clean variables in restart scenario"() {
+    setup:
+    def summary = new ExpressionEvaluationSummary()
+
+    def stage = stage {
+      refId = "1"
+      type = "evaluateVariables"
+      context["variables"] = [
+          ["key": "status", "value": "expressionToEvaluate"],
+      ]
+    }
+
+    when:
+    evaluateVariablesStage.processExpressions(stage, contextParameterProcessor, summary)
+    evaluateVariablesStage.prepareStageForRestart(stage)
+    def variables = stage.mapTo(EvaluateVariablesStage.EvaluateVariablesStageContext.class).getVariables()
+    def variablesCleaned = false
+    variables.each {
+      variablesCleaned = it.sourceExpression == null
+    }
+
+    then:
+    variablesCleaned == true
+  }
 }