Ruby: Adopt shared ConditionalCompletionSplitting implementation

ruby/ql/lib/codeql/ruby/controlflow/internal/Splitting.qll

@@ -3,7 +3,8 @@
  */
 
 private import codeql.ruby.AST as Ast
-private import Completion
+private import Completion as Comp
+private import Comp
 private import ControlFlowGraphImpl
 private import SuccessorTypes
 private import codeql.ruby.controlflow.ControlFlowGraph
@@ -64,54 +65,64 @@ private module ConditionalCompletionSplitting {
 
   int getNextListOrder() { result = 1 }
 
-  private class ConditionalCompletionSplitImpl extends SplitImpl instanceof ConditionalCompletionSplit
-  {
-    ConditionalCompletion completion;
-
-    ConditionalCompletionSplitImpl() { this = TConditionalCompletionSplit(completion) }
+  private module Input implements SplitImplementations::ConditionalCompletionSplittingInputSig {
+    class ConditionalCompletion = Comp::ConditionalCompletion;
 
-    override ConditionalCompletionSplitKind getKind() { any() }
+    class ConditionalCompletionSplitImpl = ConditionalCompletionSplitImpl_;
 
-    override predicate hasEntry(AstNode pred, AstNode succ, Completion c) {
-      succ(pred, succ, c) and
-      last(succ, _, completion) and
+    bindingset[parent, parentCompletion]
+    predicate condPropagateExpr(
+      AstNode parent, ConditionalCompletion parentCompletion, AstNode child,
+      ConditionalCompletion childCompletion
+    ) {
+      child = parent.(Ast::NotExpr).getOperand() and
+      childCompletion.(BooleanCompletion).getDual() = parentCompletion
+      or
+      childCompletion = parentCompletion and
       (
-        last(succ.(Ast::NotExpr).getOperand(), pred, c) and
-        completion.(BooleanCompletion).getDual() = c
-        or
-        last(succ.(Ast::LogicalAndExpr).getAnOperand(), pred, c) and
-        completion = c
+        child = parent.(Ast::LogicalAndExpr).getAnOperand()
         or
-        last(succ.(Ast::LogicalOrExpr).getAnOperand(), pred, c) and
-        completion = c
+        child = parent.(Ast::LogicalOrExpr).getAnOperand()
         or
-        last(succ.(Ast::StmtSequence).getLastStmt(), pred, c) and
-        completion = c
+        child = parent.(Ast::StmtSequence).getLastStmt()
         or
-        last(succ.(Ast::ConditionalExpr).getBranch(_), pred, c) and
-        completion = c
+        child = parent.(Ast::ConditionalExpr).getBranch(_)
       )
+    }
+  }
+
+  private class SharedImpl =
+    SplitImplementations::ConditionalCompletionSplitting<Input>::ConditionalCompletionSplit;
+
+  private class ConditionalCompletionSplitImpl_ extends SplitImpl instanceof ConditionalCompletionSplit
+  {
+    ConditionalCompletion getCompletion() { this = TConditionalCompletionSplit(result) }
+
+    override ConditionalCompletionSplitKind getKind() { any() }
+
+    override predicate hasEntry(AstNode pred, AstNode succ, Completion c) {
+      this.(SharedImpl).hasEntry(pred, succ, c)
       or
       succ(pred, succ, c) and
       succ instanceof Ast::WhenClause and
-      completion = c
+      c = this.getCompletion()
     }
 
-    override predicate hasEntryScope(CfgScope scope, AstNode succ) { none() }
+    override predicate hasEntryScope(CfgScope scope, AstNode first) {
+      this.(SharedImpl).hasEntryScope(scope, first)
+    }
 
     override predicate hasExit(AstNode pred, AstNode succ, Completion c) {
-      this.appliesTo(pred) and
-      succ(pred, succ, c) and
-      if c instanceof ConditionalCompletion then completion = c else any()
+      this.(SharedImpl).hasExit(pred, succ, c)
     }
 
     override predicate hasExitScope(CfgScope scope, AstNode last, Completion c) {
-      this.appliesTo(last) and
-      succExit(scope, last, c) and
-      if c instanceof ConditionalCompletion then completion = c else any()
+      this.(SharedImpl).hasExitScope(scope, last, c)
     }
 
-    override predicate hasSuccessor(AstNode pred, AstNode succ, Completion c) { none() }
+    override predicate hasSuccessor(AstNode pred, AstNode succ, Completion c) {
+      this.(SharedImpl).hasSuccessor(pred, succ, c)
+    }
   }
 }