CFG: Model nodes with simple flow

ql/src/codeql_ruby/controlflow/internal/ControlFlowGraphImpl.qll

@@ -228,6 +228,14 @@ abstract private class LeafTree extends PreOrderTree, PostOrderTree {
 
 /** Defines the CFG by dispatch on the various AST types. */
 private module Trees {
+  private class AliasTree extends StandardPreOrderTree, Alias {
+    final override AstNode getChildNode(int i) {
+      i = 0 and result = this.getName()
+      or
+      i = 1 and result = this.getAlias()
+    }
+  }
+
   private class ArgumentListTree extends StandardPostOrderTree, ArgumentList {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
 
@@ -246,6 +254,22 @@ private module Trees {
     }
   }
 
+  private class BareStringTree extends StandardPostOrderTree, BareString {
+    final override AstNode getChildNode(int i) {
+      result = this.getChild(i) and result instanceof Interpolation
+    }
+  }
+
+  private class BareSymbolTree extends StandardPostOrderTree, BareSymbol {
+    final override AstNode getChildNode(int i) {
+      result = this.getChild(i) and result instanceof Interpolation
+    }
+  }
+
+  private class BeginTree extends StandardPreOrderTree, Begin {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+  }
+
   private class BeginBlockTree extends StandardPreOrderTree, BeginBlock {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
   }
@@ -260,7 +284,21 @@ private module Trees {
     }
   }
 
-  private class BlockParametersTree extends LeafTree, BlockParameters {
+  private class BlockTree extends StandardPreOrderTree, Block {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+
+    override predicate isHidden() { any() }
+  }
+
+  private class BlockArgumentTree extends StandardPostOrderTree, BlockArgument {
+    final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+  }
+
+  private class BlockParameterTree extends LeafTree, BlockParameter { }
+
+  private class BlockParametersTree extends StandardPreOrderTree, BlockParameters {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+
     override predicate isHidden() { any() }
   }
 
@@ -314,10 +352,33 @@ private module Trees {
     }
   }
 
+  private class ChainedStringTree extends StandardPostOrderTree, ChainedString {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+
+    override predicate isHidden() { any() }
+  }
+
+  private class CharacterTree extends LeafTree, Character { }
+
   private class ClassTree extends StandardPreOrderTree, Class {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
   }
 
+  private class ClassVariableTree extends LeafTree, ClassVariable { }
+
+  private class ComplexTree extends LeafTree, Complex { }
+
+  private class ConstantTree extends LeafTree, Constant { }
+
+  private class DestructuredLeftAssignmentTree extends StandardPostOrderTree,
+    DestructuredLeftAssignment {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+  }
+
+  private class DestructuredParameterTree extends StandardPostOrderTree, DestructuredParameter {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+  }
+
   private class DoTree extends StandardPreOrderTree, Do {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
 
@@ -330,16 +391,50 @@ private module Trees {
     override predicate isHidden() { any() }
   }
 
+  private class ElementReferenceTree extends StandardPostOrderTree, ElementReference {
+    final override AstNode getChildNode(int i) {
+      i = 0 and result = this.getObject()
+      or
+      result = this.getChild(i - 1)
+    }
+  }
+
   private class ElseTree extends StandardPreOrderTree, Else {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
 
     override predicate isHidden() { any() }
   }
 
+  private class EmptyStatementTree extends LeafTree, EmptyStatement { }
+
   private class EndBlockTree extends StandardPreOrderTree, EndBlock {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
   }
 
+  private class EnsureTree extends StandardPreOrderTree, Ensure {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+
+    override predicate isHidden() { any() }
+  }
+
+  private class EscapeSequenceTree extends LeafTree, EscapeSequence { }
+
+  private class ExceptionVariableTree extends StandardPostOrderTree, ExceptionVariable {
+    final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+
+    override predicate isHidden() { any() }
+  }
+
+  private class ExceptionsTree extends StandardPostOrderTree, Exceptions {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+
+    override predicate isHidden() { any() }
+  }
+
+  private class FalseTree extends LeafTree, False { }
+
+  private class FloatTree extends LeafTree, Float { }
+
   /**
    * Control flow of a for-in loop
    *
@@ -431,6 +526,18 @@ private module Trees {
     }
   }
 
+  private class GlobalVariableTree extends LeafTree, GlobalVariable { }
+
+  private class HashTree extends StandardPostOrderTree, Hash {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+  }
+
+  private class HashSplatArgumentTree extends StandardPostOrderTree, HashSplatArgument {
+    final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+  }
+
+  private class HashSplatParameterTree extends LeafTree, HashSplatParameter { }
+
   private class HeredocBeginningTree extends StandardPreOrderTree, HeredocBeginning {
     final override AstNode getChildNode(int i) {
       i = 0 and
@@ -452,6 +559,16 @@ private module Trees {
     }
   }
 
+  private class HeredocBodyTree extends StandardPostOrderTree, HeredocBody {
+    final override AstNode getChildNode(int i) {
+      result = this.getChild(i) and result instanceof Interpolation
+    }
+  }
+
+  private class HeredocContentTree extends LeafTree, HeredocContent { }
+
+  private class HeredocEndTree extends LeafTree, HeredocEnd { }
+
   private class IdentifierTree extends LeafTree, Identifier { }
 
   private class IfElsifTree extends PreOrderTree, IfElsifAstNode {
@@ -491,8 +608,40 @@ private module Trees {
     override predicate isHidden() { any() }
   }
 
+  private class InstanceVariableTree extends LeafTree, InstanceVariable { }
+
   private class IntegerTree extends LeafTree, Integer { }
 
+  private class InterpolationTree extends StandardPostOrderTree, Interpolation {
+    final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+  }
+
+  private class KeywordParameterTree extends StandardPostOrderTree, KeywordParameter {
+    final override AstNode getChildNode(int i) { result = this.getValue() and i = 0 }
+  }
+
+  private class LambdaTree extends StandardPreOrderTree, Lambda {
+    final override AstNode getChildNode(int i) {
+      result = this.getParameters() and i = 0
+      or
+      result = this.getBody() and i = 1
+    }
+
+    override predicate isHidden() { any() }
+  }
+
+  private class LambdaParametersTree extends StandardPreOrderTree, LambdaParameters {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+
+    override predicate isHidden() { any() }
+  }
+
+  private class LeftAssignmentListTree extends StandardPostOrderTree, LeftAssignmentList {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+
+    override predicate isHidden() { any() }
+  }
+
   class LogicalAndTree extends PostOrderTree, LogicalAndAstNode {
     final override predicate propagatesAbnormal(AstNode child) { child in [left, right] }
 
@@ -564,6 +713,12 @@ private module Trees {
     }
   }
 
+  private class MethodParametersTree extends StandardPreOrderTree, MethodParameters {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+
+    override predicate isHidden() { any() }
+  }
+
   private class ModuleTree extends StandardPreOrderTree, Module {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
   }
@@ -572,6 +727,8 @@ private module Trees {
     final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
   }
 
+  private class NilTree extends LeafTree, Nil { }
+
   private class OperatorAssignmentTree extends StandardPostOrderTree, OperatorAssignment {
     final override AstNode getChildNode(int i) {
       result = this.getLeft() and i = 0
@@ -580,6 +737,18 @@ private module Trees {
     }
   }
 
+  private class OptionalParameterTree extends StandardPostOrderTree, OptionalParameter {
+    final override AstNode getChildNode(int i) { result = this.getValue() and i = 0 }
+  }
+
+  private class PairTree extends StandardPostOrderTree, Pair {
+    final override AstNode getChildNode(int i) {
+      result = this.getKey() and i = 0
+      or
+      result = this.getValue() and i = 1
+    }
+  }
+
   private class ParenthesizedStatementsTree extends StandardPostOrderTree, ParenthesizedStatements {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
   }
@@ -594,10 +763,32 @@ private module Trees {
     override predicate isHidden() { any() }
   }
 
+  private class RangeTree extends StandardPostOrderTree, Range {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+  }
+
+  private class RationalTree extends LeafTree, Rational { }
+
   private class RedoTree extends StandardPostOrderTree, Redo {
     final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
   }
 
+  private class RegexTree extends StandardPostOrderTree, Regex {
+    final override AstNode getChildNode(int i) {
+      result = this.getChild(i) and result instanceof Interpolation
+    }
+  }
+
+  private class RescueTree extends StandardPreOrderTree, Rescue {
+    final override AstNode getChildNode(int i) {
+      result = this.getExceptions() and i = 0
+      or
+      result = this.getVariable() and i = 1
+      or
+      result = this.getBody() and i = 2
+    }
+  }
+
   private class RescueModifierTree extends PreOrderTree, RescueModifier {
     final override predicate propagatesAbnormal(AstNode child) { child = this.getHandler() }
 
@@ -619,10 +810,36 @@ private module Trees {
     }
   }
 
+  private class RestAssignmentTree extends StandardPostOrderTree, RestAssignment {
+    final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+  }
+
+  private class RetryTree extends StandardPreOrderTree, Retry {
+    final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+  }
+
   private class ReturnTree extends StandardPostOrderTree, Return {
     final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
   }
 
+  private class RightAssignmentListTree extends StandardPostOrderTree, RightAssignmentList {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+
+    override predicate isHidden() { any() }
+  }
+
+  private class ScopeResolutionTree extends StandardPostOrderTree, ScopeResolution {
+    final override AstNode getChildNode(int i) {
+      result = this.getScope() and i = 0
+      or
+      result = this.getName() and i = 1
+    }
+  }
+
+  private class SelfTree extends LeafTree, Self { }
+
+  private class SetterTree extends LeafTree, Setter { }
+
   private class SingletonClassTree extends StandardPreOrderTree, SingletonClass {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
 
@@ -635,7 +852,47 @@ private module Trees {
     override predicate isHidden() { any() }
   }
 
-  private class StringTree extends LeafTree, String { }
+  private class SplatArgumentTree extends StandardPostOrderTree, SplatArgument {
+    final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+  }
+
+  private class SplatParameterTree extends StandardPostOrderTree, SplatArgument {
+    final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+  }
+
+  private class StringTree extends StandardPostOrderTree, String {
+    final override AstNode getChildNode(int i) {
+      result = this.getChild(i) and result instanceof Interpolation
+    }
+  }
+
+  private class StringArrayTree extends StandardPostOrderTree, StringArray {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+  }
+
+  private class StringContentTree extends LeafTree, StringContent { }
+
+  private class SubshellTree extends StandardPostOrderTree, Subshell {
+    final override AstNode getChildNode(int i) {
+      result = this.getChild(i) and result instanceof Interpolation
+    }
+  }
+
+  private class SuperTree extends LeafTree, Super { }
+
+  private class SuperclassTree extends StandardPostOrderTree, Superclass {
+    final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+  }
+
+  private class SymbolTree extends StandardPostOrderTree, Symbol {
+    final override AstNode getChildNode(int i) {
+      result = this.getChild(i) and result instanceof Interpolation
+    }
+  }
+
+  private class SymbolArrayTree extends StandardPostOrderTree, SymbolArray {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+  }
 
   private class ThenTree extends StandardPreOrderTree, Then {
     final override AstNode getChildNode(int i) { result = this.getChild(i) }
@@ -643,12 +900,18 @@ private module Trees {
     override predicate isHidden() { any() }
   }
 
+  private class TrueTree extends LeafTree, True { }
+
   private class UnaryTree extends StandardPostOrderTree, Unary {
     UnaryTree() { not this instanceof LogicalNotAstNode }
 
     final override AstNode getChildNode(int i) { result = this.getOperand() and i = 0 }
   }
 
+  private class UndefTree extends StandardPreOrderTree, Undef {
+    final override AstNode getChildNode(int i) { result = this.getChild(i) }
+  }
+
   private class WhenTree extends PreOrderTree, When {
     final override predicate propagatesAbnormal(AstNode child) { child = this.getPattern(_) }
 
@@ -718,6 +981,10 @@ private module Trees {
   }
 }
 
+private class YieldTree extends StandardPreOrderTree, Yield {
+  final override AstNode getChildNode(int i) { result = this.getChild() and i = 0 }
+}
+
 cached
 private module Cached {
   private predicate isAbnormalExitType(SuccessorType t) {

ql/test/library-tests/controlflow/graph/Cfg.expected

@@ -1,4 +1,41 @@
 nodes
+| cfg.rb:1:1:22:2 | enter top-level |
+| cfg.rb:1:1:22:2 | exit top-level |
+| cfg.rb:1:1:22:2 | exit top-level (normal) |
+| cfg.rb:3:1:3:13 | Alias |
+| cfg.rb:3:7:3:9 | foo |
+| cfg.rb:3:11:3:13 | bar |
+| cfg.rb:5:1:5:1 | b |
+| cfg.rb:5:1:5:6 | Assignment |
+| cfg.rb:5:5:5:6 | 42 |
+| cfg.rb:7:1:7:21 | SymbolArray |
+| cfg.rb:7:4:7:12 | BareSymbol |
+| cfg.rb:7:7:7:12 | Interpolation |
+| cfg.rb:7:10:7:10 | b |
+| cfg.rb:7:14:7:20 | BareSymbol |
+| cfg.rb:9:1:9:21 | StringArray |
+| cfg.rb:9:4:9:12 | BareString |
+| cfg.rb:9:7:9:12 | Interpolation |
+| cfg.rb:9:10:9:10 | b |
+| cfg.rb:9:14:9:20 | BareString |
+| cfg.rb:12:1:14:3 | Begin |
+| cfg.rb:13:3:13:6 | puts |
+| cfg.rb:13:3:13:8 | MethodCall |
+| cfg.rb:13:8:13:8 | 4 |
+| cfg.rb:16:1:18:1 | BeginBlock |
+| cfg.rb:16:1:18:1 | enter BEGIN block |
+| cfg.rb:16:1:18:1 | exit BEGIN block |
+| cfg.rb:16:1:18:1 | exit BEGIN block (normal) |
+| cfg.rb:17:3:17:6 | puts |
+| cfg.rb:17:3:17:14 | MethodCall |
+| cfg.rb:17:8:17:14 | String |
+| cfg.rb:20:1:22:1 | EndBlock |
+| cfg.rb:20:1:22:1 | enter END block |
+| cfg.rb:20:1:22:1 | exit END block |
+| cfg.rb:20:1:22:1 | exit END block (normal) |
+| cfg.rb:21:3:21:6 | puts |
+| cfg.rb:21:3:21:14 | MethodCall |
+| cfg.rb:21:8:21:14 | String |
 | exit.rb:1:1:6:3 | enter m1 |
 | exit.rb:1:1:6:3 | exit m1 |
 | exit.rb:1:1:6:3 | exit m1 (abnormal) |
@@ -171,6 +208,40 @@ nodes
 | raise.rb:5:3:5:15 | MethodCall |
 | raise.rb:5:8:5:15 | String |
 edges
+| cfg.rb:1:1:22:2 | enter top-level | cfg.rb:3:1:3:13 | Alias | semmle.label | successor |
+| cfg.rb:1:1:22:2 | exit top-level (normal) | cfg.rb:1:1:22:2 | exit top-level | semmle.label | successor |
+| cfg.rb:3:1:3:13 | Alias | cfg.rb:3:7:3:9 | foo | semmle.label | successor |
+| cfg.rb:3:7:3:9 | foo | cfg.rb:3:11:3:13 | bar | semmle.label | successor |
+| cfg.rb:3:11:3:13 | bar | cfg.rb:5:5:5:6 | 42 | semmle.label | successor |
+| cfg.rb:5:1:5:1 | b | cfg.rb:5:1:5:6 | Assignment | semmle.label | successor |
+| cfg.rb:5:1:5:6 | Assignment | cfg.rb:7:10:7:10 | b | semmle.label | successor |
+| cfg.rb:5:5:5:6 | 42 | cfg.rb:5:1:5:1 | b | semmle.label | successor |
+| cfg.rb:7:1:7:21 | SymbolArray | cfg.rb:9:10:9:10 | b | semmle.label | successor |
+| cfg.rb:7:4:7:12 | BareSymbol | cfg.rb:7:14:7:20 | BareSymbol | semmle.label | successor |
+| cfg.rb:7:7:7:12 | Interpolation | cfg.rb:7:4:7:12 | BareSymbol | semmle.label | successor |
+| cfg.rb:7:10:7:10 | b | cfg.rb:7:7:7:12 | Interpolation | semmle.label | successor |
+| cfg.rb:7:14:7:20 | BareSymbol | cfg.rb:7:1:7:21 | SymbolArray | semmle.label | successor |
+| cfg.rb:9:1:9:21 | StringArray | cfg.rb:12:1:14:3 | Begin | semmle.label | successor |
+| cfg.rb:9:4:9:12 | BareString | cfg.rb:9:14:9:20 | BareString | semmle.label | successor |
+| cfg.rb:9:7:9:12 | Interpolation | cfg.rb:9:4:9:12 | BareString | semmle.label | successor |
+| cfg.rb:9:10:9:10 | b | cfg.rb:9:7:9:12 | Interpolation | semmle.label | successor |
+| cfg.rb:9:14:9:20 | BareString | cfg.rb:9:1:9:21 | StringArray | semmle.label | successor |
+| cfg.rb:12:1:14:3 | Begin | cfg.rb:13:8:13:8 | 4 | semmle.label | successor |
+| cfg.rb:13:3:13:6 | puts | cfg.rb:13:3:13:8 | MethodCall | semmle.label | successor |
+| cfg.rb:13:3:13:8 | MethodCall | cfg.rb:1:1:22:2 | exit top-level (normal) | semmle.label | successor |
+| cfg.rb:13:8:13:8 | 4 | cfg.rb:13:3:13:6 | puts | semmle.label | successor |
+| cfg.rb:16:1:18:1 | BeginBlock | cfg.rb:17:8:17:14 | String | semmle.label | successor |
+| cfg.rb:16:1:18:1 | enter BEGIN block | cfg.rb:16:1:18:1 | BeginBlock | semmle.label | successor |
+| cfg.rb:16:1:18:1 | exit BEGIN block (normal) | cfg.rb:16:1:18:1 | exit BEGIN block | semmle.label | successor |
+| cfg.rb:17:3:17:6 | puts | cfg.rb:17:3:17:14 | MethodCall | semmle.label | successor |
+| cfg.rb:17:3:17:14 | MethodCall | cfg.rb:16:1:18:1 | exit BEGIN block (normal) | semmle.label | successor |
+| cfg.rb:17:8:17:14 | String | cfg.rb:17:3:17:6 | puts | semmle.label | successor |
+| cfg.rb:20:1:22:1 | EndBlock | cfg.rb:21:8:21:14 | String | semmle.label | successor |
+| cfg.rb:20:1:22:1 | enter END block | cfg.rb:20:1:22:1 | EndBlock | semmle.label | successor |
+| cfg.rb:20:1:22:1 | exit END block (normal) | cfg.rb:20:1:22:1 | exit END block | semmle.label | successor |
+| cfg.rb:21:3:21:6 | puts | cfg.rb:21:3:21:14 | MethodCall | semmle.label | successor |
+| cfg.rb:21:3:21:14 | MethodCall | cfg.rb:20:1:22:1 | exit END block (normal) | semmle.label | successor |
+| cfg.rb:21:8:21:14 | String | cfg.rb:21:3:21:6 | puts | semmle.label | successor |
 | exit.rb:1:1:6:3 | enter m1 | exit.rb:2:3:4:5 | If | semmle.label | successor |
 | exit.rb:1:1:6:3 | exit m1 (abnormal) | exit.rb:1:1:6:3 | exit m1 | semmle.label | successor |
 | exit.rb:1:1:6:3 | exit m1 (normal) | exit.rb:1:1:6:3 | exit m1 | semmle.label | successor |

ql/test/library-tests/controlflow/graph/cfg.rb

@@ -0,0 +1,22 @@
+def bar; end
+
+alias foo bar
+
+b = 42
+
+%I(one#{ b } another) # bare symbol
+
+%W(one#{ b } another) # bare string
+
+
+begin 
+  puts 4
+end
+
+BEGIN {
+  puts "hello"
+}
+
+END {
+  puts "world"
+}