fix: simplify Ast

Author: Alvaro Muñoz

ql/lib/codeql/actions/Ast.qll

@@ -149,7 +149,7 @@ class JobStmt extends Statement instanceof Actions::Job {
    *   out1: ${steps.foo.bar}
    *   out2: ${steps.foo.baz}
    */
-  JobOutputStmt getOutputStmt() { result = this.(Actions::Job).lookup("outputs") }
+  OutputsStmt getOutputsStmt() { result = this.(Actions::Job).lookup("outputs") }
 
   /**
    * Reusable workflow jobs may have Uses children
@@ -166,28 +166,6 @@ class JobStmt extends Statement instanceof Actions::Job {
   }
 }
 
-/**
- * Declaration of the outputs for the job.
- * eg:
- *   out1: ${steps.foo.bar}
- *   out2: ${steps.foo.baz}
- */
-class JobOutputStmt extends Statement instanceof YamlMapping {
-  JobStmt job;
-
-  JobOutputStmt() { job.(YamlMapping).lookup("outputs") = this }
-
-  YamlMapping asYamlMapping() { result = this }
-
-  /**
-   * Gets a specific value expression
-   * eg: ${steps.foo.bar}
-   */
-  Expression getOutputExpr(string id) {
-    this.(YamlMapping).maps(any(YamlScalar s | s.getValue() = id), result)
-  }
-}
-
 /**
  * A Step is a single task that can be executed as part of a job.
  */
@@ -435,9 +413,9 @@ class NeedsCtxAccessExpr extends CtxAccessExpr {
     job.getLocation().getFile() = this.getLocation().getFile() and
     (
       // regular jobs
-      job.getOutputStmt().getOutputExpr(fieldName) = result
+      job.getOutputsStmt() = result
       or
-      // jobs calling reusable workflows
+      // reusable workflow calling jobs
       job.getUsesExpr() = result
     )
   }
@@ -464,7 +442,7 @@ class JobsCtxAccessExpr extends CtxAccessExpr {
     exists(JobStmt job |
       job.getId() = jobId and
       job.getLocation().getFile() = this.getLocation().getFile() and
-      job.getOutputStmt().getOutputExpr(fieldName) = result
+      job.getOutputsStmt() = result
     )
   }
 }

ql/lib/codeql/actions/controlflow/internal/Cfg.qll

@@ -231,7 +231,7 @@ private class JobTree extends StandardPreOrderTree instanceof JobStmt {
       rank[i](Expression child, Location l |
         (
           child = super.getAStepStmt() or
-          child = super.getOutputStmt() or
+          child = super.getOutputsStmt() or
           child = super.getUsesExpr()
         ) and
         l = child.getLocation()
@@ -243,10 +243,6 @@ private class JobTree extends StandardPreOrderTree instanceof JobStmt {
   }
 }
 
-private class JobOutputTree extends StandardPreOrderTree instanceof JobOutputStmt {
-  override ControlFlowTree getChildNode(int i) { result = super.asYamlMapping().getValueNode(i) }
-}
-
 private class StepUsesTree extends StandardPreOrderTree instanceof StepUsesExpr {
   override ControlFlowTree getChildNode(int i) {
     result =