Desugar compound assignments

2026-04-25 08:45:14 +02:00 · 2021-06-04 10:39:06 +02:00
parent da9adfbab4
commit 6678ac0347
15 changed files with 688 additions and 104 deletions
--- a/ql/src/codeql_ruby/ast/Literal.qll
+++ b/ql/src/codeql_ruby/ast/Literal.qll
@@ -752,31 +752,25 @@ class HashLiteral extends Literal, THashLiteral {
 * ```
 */
 class RangeLiteral extends Literal, TRangeLiteral {
-  private Generated::Range g;
-
-  RangeLiteral() { this = TRangeLiteral(g) }
-
  final override string getAPrimaryQlClass() { result = "RangeLiteral" }

  /** Gets the begin expression of this range, if any. */
-  final Expr getBegin() { toGenerated(result) = g.getBegin() }
+  Expr getBegin() { none() }

  /** Gets the end expression of this range, if any. */
-  final Expr getEnd() { toGenerated(result) = g.getEnd() }
+  Expr getEnd() { none() }

  /**
   * Holds if the range is inclusive of the end value, i.e. uses the `..`
   * operator.
   */
-  final predicate isInclusive() { g instanceof @range_dotdot }
+  predicate isInclusive() { none() }

  /**
   * Holds if the range is exclusive of the end value, i.e. uses the `...`
   * operator.
   */
-  final predicate isExclusive() { g instanceof @range_dotdotdot }
-
-  final override string toString() { result = "_ " + g.getOperator() + " _" }
+  predicate isExclusive() { none() }

  final override AstNode getAChild(string pred) {
    result = super.getAChild(pred)
@@ -785,6 +779,44 @@ class RangeLiteral extends Literal, TRangeLiteral {
    or
    pred = "getEnd" and result = this.getEnd()
  }
+
+  final override string toString() {
+    exists(string op |
+      this.isInclusive() and op = ".."
+      or
+      this.isExclusive() and op = "..."
+    |
+      result = "_ " + op + " _"
+    )
+  }
+}
+
+private class RangeLiteralReal extends RangeLiteral, TRangeLiteralReal {
+  private Generated::Range g;
+
+  RangeLiteralReal() { this = TRangeLiteralReal(g) }
+
+  final override Expr getBegin() { toGenerated(result) = g.getBegin() }
+
+  final override Expr getEnd() { toGenerated(result) = g.getEnd() }
+
+  final override predicate isInclusive() { g instanceof @range_dotdot }
+
+  final override predicate isExclusive() { g instanceof @range_dotdotdot }
+}
+
+private class RangeLiteralSynth extends RangeLiteral, TRangeLiteralSynth {
+  private boolean inclusive;
+
+  RangeLiteralSynth() { this = TRangeLiteralSynth(_, _, inclusive) }
+
+  final override Expr getBegin() { result = TIntegerLiteralSynth(this, 0, _) }
+
+  final override Expr getEnd() { result = TIntegerLiteralSynth(this, 1, _) }
+
+  final override predicate isInclusive() { inclusive = true }
+
+  final override predicate isExclusive() { inclusive = false }
 }

 /**
--- a/ql/src/codeql_ruby/ast/Operation.qll
+++ b/ql/src/codeql_ruby/ast/Operation.qll
@@ -91,12 +91,8 @@ class UnaryMinusExpr extends UnaryArithmeticOperation, TUnaryMinusExpr {
 * foo(*args)
 * ```
 */
-class SplatExpr extends UnaryOperation, TSplatArgument {
-  private Generated::SplatArgument g;
-
-  SplatExpr() { this = TSplatArgument(g) }
-
-  final override Expr getOperand() { toGenerated(result) = g.getChild() }
+class SplatExpr extends UnaryOperation, TSplatExpr {
+  final override Expr getOperand() { result = this.(SplatExprImpl).getOperandImpl() }

  final override string getOperator() { result = "*" }

@@ -109,10 +105,10 @@ class SplatExpr extends UnaryOperation, TSplatArgument {
 * foo(**options)
 * ```
 */
-class HashSplatExpr extends UnaryOperation, THashSplatArgument {
+class HashSplatExpr extends UnaryOperation, THashSplatExpr {
  private Generated::HashSplatArgument g;

-  HashSplatExpr() { this = THashSplatArgument(g) }
+  HashSplatExpr() { this = THashSplatExpr(g) }

  final override Expr getOperand() { toGenerated(result) = g.getChild() }

--- a/ql/src/codeql_ruby/ast/Pattern.qll
+++ b/ql/src/codeql_ruby/ast/Pattern.qll
@@ -1,6 +1,7 @@
 private import codeql_ruby.AST
 private import codeql.Locations
 private import internal.AST
+private import internal.Pattern
 private import internal.TreeSitter
 private import internal.Variable

@@ -62,20 +63,9 @@ class VariablePattern extends Pattern, LhsExpr, TVariablePattern { }
 class TuplePattern extends Pattern, TTuplePattern {
  override string getAPrimaryQlClass() { result = "TuplePattern" }

-  private Generated::AstNode getChild(int i) {
-    result = toGenerated(this).(Generated::DestructuredParameter).getChild(i)
-    or
-    result = toGenerated(this).(Generated::DestructuredLeftAssignment).getChild(i)
-    or
-    toGenerated(this) =
-      any(Generated::LeftAssignmentList lal |
-        if
-          strictcount(int j | exists(lal.getChild(j))) = 1 and
-          lal.getChild(0) instanceof Generated::DestructuredLeftAssignment
-        then result = lal.getChild(0).(Generated::DestructuredLeftAssignment).getChild(i)
-        else result = lal.getChild(i)
-      )
-  }
+  private TuplePatternImpl getImpl() { result = toGenerated(this) }
+
+  private Generated::AstNode getChild(int i) { result = this.getImpl().getChildNode(i) }

  /** Gets the `i`th pattern in this tuple pattern. */
  final Pattern getElement(int i) {
@@ -96,9 +86,7 @@ class TuplePattern extends Pattern, TTuplePattern {
   * a, b, *rest, c, d = value
   * ```
   */
-  final int getRestIndex() {
-    result = unique(int i | getChild(i) instanceof Generated::RestAssignment)
-  }
+  final int getRestIndex() { result = this.getImpl().getRestIndex() }

  override Variable getAVariable() { result = this.getElement(_).getAVariable() }

--- a/ql/src/codeql_ruby/ast/internal/AST.qll
+++ b/ql/src/codeql_ruby/ast/internal/AST.qll
@@ -138,7 +138,7 @@ private module Cached {
    } or
    THashKeySymbolLiteral(Generated::HashKeySymbol g) or
    THashLiteral(Generated::Hash g) or
-    THashSplatArgument(Generated::HashSplatArgument g) or
+    THashSplatExpr(Generated::HashSplatArgument g) or
    THashSplatParameter(Generated::HashSplatParameter g) or
    THereDoc(Generated::HeredocBeginning g) or
    TIdentifierMethodCall(Generated::Identifier g) { isIdentifierMethodCall(g) } or
@@ -198,7 +198,10 @@ private module Cached {
    TParenthesizedExpr(Generated::ParenthesizedStatements g) or
    TRShiftExprReal(Generated::Binary g) { g instanceof @binary_ranglerangle } or
    TRShiftExprSynth(AST::AstNode parent, int i) { mkSynthChild(RShiftExprKind(), parent, i) } or
-    TRangeLiteral(Generated::Range g) or
+    TRangeLiteralReal(Generated::Range g) or
+    TRangeLiteralSynth(AST::AstNode parent, int i, boolean inclusive) {
+      mkSynthChild(RangeLiteralKind(inclusive), parent, i)
+    } or
    TRationalLiteral(Generated::Rational g) or
    TRedoStmt(Generated::Redo g) or
    TRegexLiteral(Generated::Regex g) or
@@ -232,7 +235,8 @@ private module Cached {
    TSingletonClass(Generated::SingletonClass g) or
    TSingletonMethod(Generated::SingletonMethod g) or
    TSpaceshipExpr(Generated::Binary g) { g instanceof @binary_langleequalrangle } or
-    TSplatArgument(Generated::SplatArgument g) or
+    TSplatExprReal(Generated::SplatArgument g) or
+    TSplatExprSynth(AST::AstNode parent, int i) { mkSynthChild(SplatExprKind(), parent, i) } or
    TSplatParameter(Generated::SplatParameter g) or
    TStmtSequenceSynth(AST::AstNode parent, int i) { mkSynthChild(StmtSequenceKind(), parent, i) } or
    TStringArrayLiteral(Generated::StringArray g) or
@@ -337,7 +341,7 @@ private module Cached {
    n = TGlobalVariableAccessReal(result, _) or
    n = THashKeySymbolLiteral(result) or
    n = THashLiteral(result) or
-    n = THashSplatArgument(result) or
+    n = THashSplatExpr(result) or
    n = THashSplatParameter(result) or
    n = THereDoc(result) or
    n = TIdentifierMethodCall(result) or
@@ -367,7 +371,7 @@ private module Cached {
    n = TPair(result) or
    n = TParenthesizedExpr(result) or
    n = TRShiftExprReal(result) or
-    n = TRangeLiteral(result) or
+    n = TRangeLiteralReal(result) or
    n = TRationalLiteral(result) or
    n = TRedoStmt(result) or
    n = TRegexLiteral(result) or
@@ -388,7 +392,7 @@ private module Cached {
    n = TSingletonClass(result) or
    n = TSingletonMethod(result) or
    n = TSpaceshipExpr(result) or
-    n = TSplatArgument(result) or
+    n = TSplatExprReal(result) or
    n = TSplatParameter(result) or
    n = TStringArrayLiteral(result) or
    n = TStringConcatenation(result) or
@@ -458,10 +462,14 @@ private module Cached {
    or
    result = TMulExprSynth(parent, i)
    or
+    result = TRangeLiteralSynth(parent, i, _)
+    or
    result = TRShiftExprSynth(parent, i)
    or
    result = TSelfSynth(parent, i)
    or
+    result = TSplatExprSynth(parent, i)
+    or
    result = TStmtSequenceSynth(parent, i)
    or
    result = TSubExprSynth(parent, i)
@@ -493,18 +501,11 @@ private module Cached {
    )
  }

-  private Location synthLocation(AST::AstNode n) {
-    exists(Synthesis s, AST::AstNode parent, int i |
-      s.child(parent, i, _, SomeLocation(result)) and
-      n = getSynthChild(parent, i)
-    )
-  }
-
  cached
  Location getLocation(AST::AstNode n) {
-    result = synthLocation(n)
+    synthLocation(n, result)
    or
-    not exists(synthLocation(n)) and
+    not synthLocation(n, _) and
    result = toGeneratedInclSynth(n).getLocation()
  }
 }
@@ -538,9 +539,10 @@ class TSelf = TSelfReal or TSelfSynth;

 class TExpr =
  TSelf or TArgumentList or TRescueClause or TRescueModifierExpr or TPair or TStringConcatenation or
-      TCall or TBlockArgument or TSplatArgument or THashSplatArgument or TConstantAccess or
-      TControlExpr or TWhenExpr or TLiteral or TCallable or TVariableAccess or TStmtSequence or
-      TOperation or TSimpleParameter;
+      TCall or TBlockArgument or TConstantAccess or TControlExpr or TWhenExpr or TLiteral or
+      TCallable or TVariableAccess or TStmtSequence or TOperation or TSimpleParameter;
+
+class TSplatExpr = TSplatExprReal or TSplatExprSynth;

 class TStmtSequence =
  TBeginBlock or TEndBlock or TThen or TElse or TDo or TEnsure or TStringInterpolationComponent or
@@ -586,7 +588,7 @@ class TOperation = TUnaryOperation or TBinaryOperation or TAssignment;

 class TUnaryOperation =
  TUnaryLogicalOperation or TUnaryArithmeticOperation or TUnaryBitwiseOperation or TDefinedExpr or
-      TSplatArgument or THashSplatArgument;
+      TSplatExpr or THashSplatExpr;

 class TUnaryLogicalOperation = TNotExpr;

@@ -624,6 +626,8 @@ class TBinaryBitwiseOperation =

 class TLShiftExpr = TLShiftExprReal or TLShiftExprSynth;

+class TRangeLiteral = TRangeLiteralReal or TRangeLiteralSynth;
+
 class TRShiftExpr = TRShiftExprReal or TRShiftExprSynth;

 class TBitwiseAndExpr = TBitwiseAndExprReal or TBitwiseAndExprSynth;
--- a/ql/src/codeql_ruby/ast/internal/Operation.qll
+++ b/ql/src/codeql_ruby/ast/internal/Operation.qll
@@ -29,3 +29,19 @@ class AssignOperationImpl extends AssignmentImpl, AssignOperation {

  final override AstNode getRightOperandImpl() { toGenerated(result) = g.getRight() }
 }
+
+abstract class SplatExprImpl extends SplatExpr {
+  abstract Expr getOperandImpl();
+}
+
+class SplatExprReal extends SplatExprImpl, TSplatExprReal {
+  private Generated::SplatArgument g;
+
+  SplatExprReal() { this = TSplatExprReal(g) }
+
+  final override Expr getOperandImpl() { toGenerated(result) = g.getChild() }
+}
+
+class SplatExprSynth extends SplatExprImpl, TSplatExprSynth {
+  final override Expr getOperandImpl() { synthChild(this, 0, result) }
+}
--- a/ql/src/codeql_ruby/ast/internal/Pattern.qll
+++ b/ql/src/codeql_ruby/ast/internal/Pattern.qll
@@ -0,0 +1,32 @@
+private import codeql_ruby.AST
+private import AST
+private import TreeSitter
+
+abstract class TuplePatternImpl extends Generated::AstNode {
+  abstract Generated::AstNode getChildNode(int i);
+
+  final int getRestIndex() {
+    result = unique(int i | this.getChildNode(i) instanceof Generated::RestAssignment)
+  }
+}
+
+class TuplePatternParameterImpl extends TuplePatternImpl, Generated::DestructuredParameter {
+  override Generated::AstNode getChildNode(int i) { result = this.getChild(i) }
+}
+
+class DestructuredLeftAssignmentImpl extends TuplePatternImpl, Generated::DestructuredLeftAssignment {
+  override Generated::AstNode getChildNode(int i) { result = this.getChild(i) }
+}
+
+class LeftAssignmentListImpl extends TuplePatternImpl, Generated::LeftAssignmentList {
+  override Generated::AstNode getChildNode(int i) {
+    this =
+      any(Generated::LeftAssignmentList lal |
+        if
+          strictcount(int j | exists(lal.getChild(j))) = 1 and
+          lal.getChild(0) instanceof Generated::DestructuredLeftAssignment
+        then result = lal.getChild(0).(Generated::DestructuredLeftAssignment).getChild(i)
+        else result = lal.getChild(i)
+      )
+  }
+}
--- a/ql/src/codeql_ruby/ast/internal/Synthesis.qll
+++ b/ql/src/codeql_ruby/ast/internal/Synthesis.qll
@@ -4,6 +4,7 @@ private import AST
 private import TreeSitter
 private import codeql_ruby.ast.internal.Call
 private import codeql_ruby.ast.internal.Variable
+private import codeql_ruby.ast.internal.Pattern
 private import codeql_ruby.AST

 /** A synthesized AST node kind. */
@@ -18,7 +19,7 @@ newtype SynthKind =
  ExponentExprKind() or
  GlobalVariableAccessKind(GlobalVariable v) or
  InstanceVariableAccessKind(InstanceVariable v) or
-  IntegerLiteralKind(int i) { i in [0 .. 1000] } or
+  IntegerLiteralKind(int i) { i in [-1000 .. 1000] } or
  LShiftExprKind() or
  LocalVariableAccessRealKind(LocalVariableReal v) or
  LocalVariableAccessSynthKind(TLocalVariableSynth v) or
@@ -29,7 +30,9 @@ newtype SynthKind =
  } or
  ModuloExprKind() or
  MulExprKind() or
+  RangeLiteralKind(boolean inclusive) { inclusive in [false, true] } or
  RShiftExprKind() or
+  SplatExprKind() or
  StmtSequenceKind() or
  SelfKind() or
  SubExprKind()
@@ -118,8 +121,18 @@ private predicate assign(
  )
 }

+/** Holds if synthesized node `n` should have location `l`. */
+predicate synthLocation(AstNode n, Location l) {
+  exists(Synthesis s, AstNode parent, int i |
+    s.child(parent, i, _, SomeLocation(l)) and
+    n = getSynthChild(parent, i)
+  )
+}
+
 private SomeLocation getSomeLocation(AstNode n) {
  result = SomeLocation(toGenerated(n).getLocation())
+  or
+  result = SomeLocation(any(Location l | synthLocation(n, l)))
 }

 private module ImplicitSelfSynthesis {
@@ -550,3 +563,159 @@ private module AssignOperationDesugar {
    }
  }
 }
+
+private module CompoundAssignDesugar {
+  /** An assignment where the left-hand side is a tuple pattern. */
+  private class TupleAssignExpr extends AssignExpr {
+    private TuplePattern tp;
+
+    pragma[nomagic]
+    TupleAssignExpr() { tp = this.getLeftOperand() }
+
+    TuplePattern getTuplePattern() { result = tp }
+
+    pragma[nomagic]
+    Pattern getElement(int i) { result = tp.getElement(i) }
+
+    pragma[nomagic]
+    int getNumberOfElements() {
+      toGenerated(tp) = any(TuplePatternImpl impl | result = count(impl.getChildNode(_)))
+    }
+
+    pragma[nomagic]
+    int getRestIndexOrNumberOfElements() {
+      result = tp.getRestIndex()
+      or
+      toGenerated(tp) = any(TuplePatternImpl impl | not exists(impl.getRestIndex())) and
+      result = this.getNumberOfElements()
+    }
+
+    pragma[nomagic]
+    SomeLocation getRightOperandLocation() { result = getSomeLocation(this.getRightOperand()) }
+  }
+
+  pragma[nomagic]
+  private predicate compoundAssignSynthesis(AstNode parent, int i, Child child, LocationOption l) {
+    exists(TupleAssignExpr tae |
+      parent = tae and
+      i = -1 and
+      child = SynthChild(StmtSequenceKind()) and
+      l = NoneLocation()
+      or
+      exists(AstNode seq | seq = TStmtSequenceSynth(tae, -1) |
+        parent = seq and
+        i = 0 and
+        child = SynthChild(AssignExprKind()) and
+        l = tae.getRightOperandLocation()
+        or
+        exists(AstNode assign | assign = TAssignExprSynth(seq, 0) |
+          parent = assign and
+          i = 0 and
+          child = SynthChild(LocalVariableAccessSynthKind(TLocalVariableSynth(tae, 0))) and
+          l = tae.getRightOperandLocation()
+          or
+          parent = assign and
+          i = 1 and
+          child = SynthChild(SplatExprKind()) and
+          l = tae.getRightOperandLocation()
+          or
+          parent = TSplatExprSynth(assign, 1) and
+          i = 0 and
+          child = RealChild(tae.getRightOperand()) and
+          l = NoneLocation()
+        )
+        or
+        exists(Pattern p, int j, int restIndex |
+          p = tae.getElement(j) and
+          restIndex = tae.getRestIndexOrNumberOfElements()
+        |
+          parent = seq and
+          i = j + 1 and
+          child = SynthChild(AssignExprKind()) and
+          l = getSomeLocation(p)
+          or
+          exists(AstNode assign | assign = TAssignExprSynth(seq, j + 1) |
+            parent = assign and
+            i = 0 and
+            child = RealChild(p) and
+            l = NoneLocation()
+            or
+            parent = assign and
+            i = 1 and
+            child = SynthChild(MethodCallKind("[]", false, 1)) and
+            l = getSomeLocation(p)
+            or
+            l = getSomeLocation(p) and
+            (
+              parent = TMethodCallSynth(assign, 1, _, _, _) and
+              i = 0 and
+              child = SynthChild(LocalVariableAccessSynthKind(TLocalVariableSynth(tae, 0)))
+              or
+              j < restIndex and
+              parent = TMethodCallSynth(assign, 1, _, _, _) and
+              i = 1 and
+              child = SynthChild(IntegerLiteralKind(j))
+              or
+              j = restIndex and
+              (
+                parent = TMethodCallSynth(assign, 1, _, _, _) and
+                i = 1 and
+                child = SynthChild(RangeLiteralKind(true))
+                or
+                exists(AstNode call |
+                  call = TMethodCallSynth(assign, 1, _, _, _) and
+                  parent = TRangeLiteralSynth(call, 1, _)
+                |
+                  i = 0 and
+                  child = SynthChild(IntegerLiteralKind(j))
+                  or
+                  i = 1 and
+                  child = SynthChild(IntegerLiteralKind(restIndex - tae.getNumberOfElements()))
+                )
+              )
+              or
+              j > restIndex and
+              parent = TMethodCallSynth(assign, 1, _, _, _) and
+              i = 1 and
+              child = SynthChild(IntegerLiteralKind(j - tae.getNumberOfElements()))
+            )
+          )
+        )
+      )
+    )
+  }
+
+  /**
+   * ```rb
+   * x, *y, z = w
+   * ```
+   * desguars to
+   *
+   * ```rb
+   * __synth__0 = *w;
+   * x = __synth__0[0];
+   * y = __synth__0[1..-2];
+   * z = __synth__0[-1];
+   * ```
+   */
+  private class CompoundAssignSynthesis extends Synthesis {
+    final override predicate child(AstNode parent, int i, Child child, LocationOption l) {
+      compoundAssignSynthesis(parent, i, child, l)
+    }
+
+    final override predicate localVariable(AstNode n, int i) {
+      n instanceof TupleAssignExpr and
+      i = 0
+    }
+
+    final override predicate methodCall(string name, boolean setter, int arity) {
+      name = "[]" and
+      setter = false and
+      arity = 1
+    }
+
+    final override predicate excludeFromControlFlowTree(AstNode n) {
+      n = any(TupleAssignExpr tae).getTuplePattern()
+    }
+  }
+}
--- a/ql/src/codeql_ruby/controlflow/internal/ControlFlowGraphImpl.qll
+++ b/ql/src/codeql_ruby/controlflow/internal/ControlFlowGraphImpl.qll
@@ -287,7 +287,12 @@ module Trees {
  }

  private class AssignExprTree extends StandardPostOrderTree, AssignExpr {
-    AssignExprTree() { not this.getLeftOperand() instanceof MethodCall }
+    AssignExprTree() {
+      exists(Expr left | left = this.getLeftOperand() |
+        left instanceof VariableAccess or
+        left instanceof ConstantAccess
+      )
+    }

    final override ControlFlowTree getChildNode(int i) {
      result = this.getLeftOperand() and i = 0
--- a/ql/test/library-tests/ast/AstDesugar.expected
+++ b/ql/test/library-tests/ast/AstDesugar.expected
@@ -31,6 +31,82 @@ calls/calls.rb:
 #  315|         getAnOperand/getRightOperand: [IntegerLiteral] 10
 #  315|       getArgument: [IntegerLiteral] 0
 #  315|     getStmt: [LocalVariableAccess] __synth__0
+#  316| [AssignExpr] ... = ...
+#  316|   getDesugared: [StmtSequence] ...
+#  316|     getStmt: [AssignExpr] ... = ...
+#  316|       getAnOperand/getLeftOperand: [MethodCall] call to foo
+#  316|       getDesugared: [StmtSequence] ...
+#  316|         getStmt: [SetterMethodCall] call to foo=
+#  316|           getReceiver: [Self] self
+#  316|           getArgument: [AssignExpr] ... = ...
+#  316|             getAnOperand/getRightOperand: [MethodCall] call to []
+#  316|               getArgument: [IntegerLiteral] 0
+#  316|               getReceiver: [LocalVariableAccess] __synth__0
+#  316|             getAnOperand/getLeftOperand: [LocalVariableAccess] __synth__0
+#  316|         getStmt: [LocalVariableAccess] __synth__0
+#  316|     getStmt: [AssignExpr] ... = ...
+#  316|       getDesugared: [StmtSequence] ...
+#  316|         getStmt: [SetterMethodCall] call to bar=
+#  316|           getReceiver: [Self] self
+#  316|           getArgument: [AssignExpr] ... = ...
+#  316|             getAnOperand/getRightOperand: [MethodCall] call to []
+#  316|               getArgument: [RangeLiteral] _ .. _
+#  316|                 getBegin: [IntegerLiteral] 1
+#  316|                 getEnd: [IntegerLiteral] -2
+#  316|               getReceiver: [LocalVariableAccess] __synth__0
+#  316|             getAnOperand/getLeftOperand: [LocalVariableAccess] __synth__0
+#  316|         getStmt: [LocalVariableAccess] __synth__0
+#  316|       getAnOperand/getLeftOperand: [MethodCall] call to bar
+#  316|     getStmt: [AssignExpr] ... = ...
+#  316|       getDesugared: [StmtSequence] ...
+#  316|         getStmt: [SetterMethodCall] call to []=
+#  316|           getReceiver: [MethodCall] call to foo
+#  316|             getReceiver: [Self] self
+#  316|           getArgument: [AssignExpr] ... = ...
+#  316|             getAnOperand/getRightOperand: [MethodCall] call to []
+#  316|               getArgument: [IntegerLiteral] -1
+#  316|               getReceiver: [LocalVariableAccess] __synth__0
+#  316|             getAnOperand/getLeftOperand: [LocalVariableAccess] __synth__0
+#  316|           getArgument: [IntegerLiteral] 4
+#  316|         getStmt: [LocalVariableAccess] __synth__0
+#  316|       getAnOperand/getLeftOperand: [ElementReference] ...[...]
+#  316|     getStmt: [AssignExpr] ... = ...
+#  316|       getAnOperand/getRightOperand: [SplatExpr] * ...
+#  316|         getAnOperand/getOperand: [ArrayLiteral] [...]
+#  316|           getElement: [IntegerLiteral] 1
+#  316|           getElement: [IntegerLiteral] 2
+#  316|           getElement: [IntegerLiteral] 3
+#  316|           getElement: [IntegerLiteral] 4
+#  316|       getAnOperand/getLeftOperand: [LocalVariableAccess] __synth__0
+#  317| [AssignExpr] ... = ...
+#  317|   getDesugared: [StmtSequence] ...
+#  317|     getStmt: [AssignExpr] ... = ...
+#  317|       getAnOperand/getLeftOperand: [LocalVariableAccess] a
+#  317|       getAnOperand/getRightOperand: [MethodCall] call to []
+#  317|         getArgument: [IntegerLiteral] 0
+#  317|         getReceiver: [LocalVariableAccess] __synth__0
+#  317|     getStmt: [AssignExpr] ... = ...
+#  317|       getDesugared: [StmtSequence] ...
+#  317|         getStmt: [SetterMethodCall] call to []=
+#  317|           getReceiver: [MethodCall] call to foo
+#  317|             getReceiver: [Self] self
+#  317|           getArgument: [AssignExpr] ... = ...
+#  317|             getAnOperand/getRightOperand: [MethodCall] call to []
+#  317|               getArgument: [RangeLiteral] _ .. _
+#  317|                 getBegin: [IntegerLiteral] 1
+#  317|                 getEnd: [IntegerLiteral] -1
+#  317|               getReceiver: [LocalVariableAccess] __synth__0
+#  317|             getAnOperand/getLeftOperand: [LocalVariableAccess] __synth__0
+#  317|           getArgument: [IntegerLiteral] 5
+#  317|         getStmt: [LocalVariableAccess] __synth__0
+#  317|       getAnOperand/getLeftOperand: [ElementReference] ...[...]
+#  317|     getStmt: [AssignExpr] ... = ...
+#  317|       getAnOperand/getRightOperand: [SplatExpr] * ...
+#  317|         getAnOperand/getOperand: [ArrayLiteral] [...]
+#  317|           getElement: [IntegerLiteral] 1
+#  317|           getElement: [IntegerLiteral] 2
+#  317|           getElement: [IntegerLiteral] 3
+#  317|       getAnOperand/getLeftOperand: [LocalVariableAccess] __synth__0
 #  318| [AssignAddExpr] ... += ...
 #  318|   getDesugared: [StmtSequence] ...
 #  318|     getStmt: [AssignExpr] ... = ...
--- a/ql/test/library-tests/ast/calls/arguments.expected
+++ b/ql/test/library-tests/ast/calls/arguments.expected
@@ -4,6 +4,8 @@ blockArguments
 splatExpr
 | calls.rb:270:5:270:8 | * ... | calls.rb:270:6:270:8 | call to bar |
 | calls.rb:271:5:271:11 | * ... | calls.rb:271:6:271:11 | call to bar |
+| calls.rb:316:31:316:42 | * ... | calls.rb:316:31:316:42 | [...] |
+| calls.rb:317:14:317:22 | * ... | calls.rb:317:14:317:22 | [...] |
 hashSplatExpr
 | calls.rb:274:5:274:9 | ** ... | calls.rb:274:7:274:9 | call to bar |
 | calls.rb:275:5:275:12 | ** ... | calls.rb:275:7:275:12 | call to bar |
--- a/ql/test/library-tests/ast/calls/calls.expected
+++ b/ql/test/library-tests/ast/calls/calls.expected
@@ -35,8 +35,19 @@ callsWithArguments
 | calls.rb:315:1:315:6 | ...[...] | [] | 0 | calls.rb:315:5:315:5 | 0 |
 | calls.rb:315:1:315:6 | call to []= | []= | 0 | calls.rb:315:5:315:5 | 0 |
 | calls.rb:315:1:315:6 | call to []= | []= | 1 | calls.rb:315:1:315:6 | ... = ... |
+| calls.rb:316:1:316:8 | call to [] | [] | 0 | calls.rb:316:1:316:8 | 0 |
+| calls.rb:316:1:316:8 | call to foo= | foo= | 0 | calls.rb:316:1:316:8 | ... = ... |
+| calls.rb:316:12:316:19 | call to [] | [] | 0 | calls.rb:316:12:316:19 | _ .. _ |
+| calls.rb:316:12:316:19 | call to bar= | bar= | 0 | calls.rb:316:12:316:19 | ... = ... |
 | calls.rb:316:22:316:27 | ...[...] | [] | 0 | calls.rb:316:26:316:26 | 4 |
+| calls.rb:316:22:316:27 | call to [] | [] | 0 | calls.rb:316:22:316:27 | -1 |
+| calls.rb:316:22:316:27 | call to []= | []= | 0 | calls.rb:316:26:316:26 | 4 |
+| calls.rb:316:22:316:27 | call to []= | []= | 1 | calls.rb:316:22:316:27 | ... = ... |
+| calls.rb:317:1:317:1 | call to [] | [] | 0 | calls.rb:317:1:317:1 | 0 |
 | calls.rb:317:5:317:10 | ...[...] | [] | 0 | calls.rb:317:9:317:9 | 5 |
+| calls.rb:317:5:317:10 | call to [] | [] | 0 | calls.rb:317:5:317:10 | _ .. _ |
+| calls.rb:317:5:317:10 | call to []= | []= | 0 | calls.rb:317:9:317:9 | 5 |
+| calls.rb:317:5:317:10 | call to []= | []= | 1 | calls.rb:317:5:317:10 | ... = ... |
 | calls.rb:318:1:318:10 | call to count= | count= | 1 | calls.rb:318:12:318:13 | __synth__1 |
 | calls.rb:319:1:319:6 | ...[...] | [] | 0 | calls.rb:319:5:319:5 | 0 |
 | calls.rb:319:1:319:6 | call to [] | [] | 0 | calls.rb:319:5:319:5 | __synth__1 |
@@ -225,12 +236,21 @@ callsWithReceiver
 | calls.rb:315:1:315:3 | call to foo | calls.rb:315:1:315:3 | self |
 | calls.rb:315:1:315:6 | ...[...] | calls.rb:315:1:315:3 | call to foo |
 | calls.rb:315:1:315:6 | call to []= | calls.rb:315:1:315:3 | call to foo |
+| calls.rb:316:1:316:8 | call to [] | calls.rb:316:1:316:8 | __synth__0 |
 | calls.rb:316:1:316:8 | call to foo | calls.rb:316:1:316:4 | self |
+| calls.rb:316:1:316:8 | call to foo= | calls.rb:316:1:316:4 | self |
+| calls.rb:316:12:316:19 | call to [] | calls.rb:316:12:316:19 | __synth__0 |
 | calls.rb:316:12:316:19 | call to bar | calls.rb:316:12:316:15 | self |
+| calls.rb:316:12:316:19 | call to bar= | calls.rb:316:12:316:15 | self |
 | calls.rb:316:22:316:24 | call to foo | calls.rb:316:22:316:24 | self |
 | calls.rb:316:22:316:27 | ...[...] | calls.rb:316:22:316:24 | call to foo |
+| calls.rb:316:22:316:27 | call to [] | calls.rb:316:22:316:27 | __synth__0 |
+| calls.rb:316:22:316:27 | call to []= | calls.rb:316:22:316:24 | call to foo |
+| calls.rb:317:1:317:1 | call to [] | calls.rb:317:1:317:1 | __synth__0 |
 | calls.rb:317:5:317:7 | call to foo | calls.rb:317:5:317:7 | self |
 | calls.rb:317:5:317:10 | ...[...] | calls.rb:317:5:317:7 | call to foo |
+| calls.rb:317:5:317:10 | call to [] | calls.rb:317:5:317:10 | __synth__0 |
+| calls.rb:317:5:317:10 | call to []= | calls.rb:317:5:317:7 | call to foo |
 | calls.rb:318:1:318:10 | call to count | calls.rb:318:1:318:4 | __synth__0 |
 | calls.rb:318:1:318:10 | call to count | calls.rb:318:1:318:4 | self |
 | calls.rb:318:1:318:10 | call to count= | calls.rb:318:1:318:4 | __synth__0 |
@@ -287,6 +307,10 @@ superCallsWithBlock
 setterCalls
 | calls.rb:314:1:314:8 | call to foo= |
 | calls.rb:315:1:315:6 | call to []= |
+| calls.rb:316:1:316:8 | call to foo= |
+| calls.rb:316:12:316:19 | call to bar= |
+| calls.rb:316:22:316:27 | call to []= |
+| calls.rb:317:5:317:10 | call to []= |
 | calls.rb:318:1:318:10 | call to count= |
 | calls.rb:319:1:319:6 | call to []= |
 | calls.rb:320:1:320:32 | call to []= |
--- a/ql/test/library-tests/controlflow/graph/Cfg.expected
+++ b/ql/test/library-tests/controlflow/graph/Cfg.expected
@@ -870,7 +870,7 @@ cfg.rb:
 #-----|  -> ... ? ... : ...

 #   61| ... = ...
-#-----|  -> x
+#-----|  -> __synth__0

 #   61| C
 #-----|  -> "constant"
@@ -878,27 +878,87 @@ cfg.rb:
 #   61| "constant"
 #-----|  -> ... = ...

-#   62| ... = ...
+#   62| ...
 #-----|  -> pattern

-#   62| (..., ...)
-#-----|  -> 1
+#   62| ...
+#-----|  -> ...

 #   62| x
+#-----|  -> __synth__0
+
+#   62| ... = ...
+#-----|  -> __synth__0
+
+#   62| call to []
+#-----|  -> ... = ...
+
+#   62| 0
+#-----|  -> call to []
+
+#   62| __synth__0
+#-----|  -> 0
+
+#   62| call to []
+#-----|  -> * ...
+
+#   62| 1
+#-----|  -> call to []
+
+#   62| __synth__0
+#-----|  -> 1
+
+#   62| ... = ...
 #-----|  -> y

-#   62| (..., ...)
-#-----|  -> (..., ...)
+#   62| * ...
+#-----|  -> ... = ...
+
+#   62| __synth__0
+#-----|  -> __synth__0

 #   62| y
+#-----|  -> __synth__0
+
+#   62| ... = ...
 #-----|  -> z

+#   62| call to []
+#-----|  -> ... = ...
+
+#   62| 0
+#-----|  -> call to []
+
+#   62| __synth__0
+#-----|  -> 0
+
 #   62| z
-#-----|  -> (..., ...)
+#-----|  -> __synth__0
+
+#   62| ... = ...
+#-----|  -> ...
+
+#   62| call to []
+#-----|  -> ... = ...
+
+#   62| 1
+#-----|  -> call to []
+
+#   62| __synth__0
+#-----|  -> 1

 #   62| [...]
+#-----|  -> * ...
+
+#   62| ... = ...
+#-----|  -> x
+
+#   62| * ...
 #-----|  -> ... = ...

+#   62| __synth__0
+#-----|  -> 1
+
 #   62| 1
 #-----|  -> 2

@@ -1514,8 +1574,8 @@ cfg.rb:
 #-----|  -> ... rescue ...

 #  136| ... / ...
-#-----|  -> init
 #-----| raise -> self
+#-----|  -> __synth__0

 #  136| 1
 #-----|  -> 0
@@ -1527,7 +1587,7 @@ cfg.rb:
 #-----|  -> ... / ...

 #  136| call to puts
-#-----|  -> init
+#-----|  -> __synth__0

 #  136| self
 #-----|  -> "div by zero"
@@ -1535,26 +1595,62 @@ cfg.rb:
 #  136| "div by zero"
 #-----|  -> call to puts

-#  138| ... = ...
+#  138| ...
 #-----|  -> M

-#  138| (..., ...)
-#-----|  -> 1
-
 #  138| init
+#-----|  -> __synth__0
+
+#  138| ... = ...
 #-----|  -> last

+#  138| call to []
+#-----|  -> ... = ...
+
+#  138| _ .. _
+#-----|  -> call to []
+
+#  138| __synth__0
+#-----|  -> 0
+
+#  138| 0
+#-----|  -> -2
+
+#  138| -2
+#-----|  -> _ .. _
+
 #  138| last
-#-----|  -> (..., ...)
+#-----|  -> __synth__0
+
+#  138| ... = ...
+#-----|  -> ...
+
+#  138| call to []
+#-----|  -> ... = ...
+
+#  138| -1
+#-----|  -> call to []
+
+#  138| __synth__0
+#-----|  -> -1

 #  138| 1
 #-----|  -> 2

+#  138| ... = ...
+#-----|  -> init
+
+#  138| * ...
+#-----|  -> ... = ...
+
+#  138| __synth__0
+#-----|  -> 1
+
 #  138| 2
 #-----|  -> 3

 #  138| 3
-#-----|  -> ... = ...
+#-----|  -> * ...

 #  140| M
 #-----|  -> Constant
@@ -2370,7 +2466,7 @@ desugar.rb:
 #-----|  -> ... + ...

 #   21| enter m6
-#-----|  -> x
+#-----|  -> __synth__0

 #   21| m6
 #-----|  -> m7
@@ -2380,30 +2476,87 @@ desugar.rb:
 #   21| exit m6 (normal)
 #-----|  -> exit m6

-#   22| ... = ...
+#   22| x
+#-----|  -> __synth__0
+
+#   22| ...
 #-----|  -> exit m6 (normal)

-#   22| (..., ...)
-#-----|  -> 1
-
-#   22| x
+#   22| ... = ...
 #-----|  -> y

+#   22| call to []
+#-----|  -> ... = ...
+
+#   22| 0
+#-----|  -> call to []
+
+#   22| ...
+#-----|  -> ...
+
+#   22| __synth__0
+#-----|  -> 0
+
 #   22| y
+#-----|  -> __synth__0
+
+#   22| ... = ...
 #-----|  -> self

-#   22| call to bar
-#-----|  -> (..., ...)
+#   22| call to []
+#-----|  -> ... = ...
+
+#   22| _ .. _
+#-----|  -> call to []
+
+#   22| __synth__0
+#-----|  -> 1
+
+#   22| 1
+#-----|  -> -2
+
+#   22| -2
+#-----|  -> _ .. _

 #   22| call to z
-#-----|  -> call to bar
+#-----|  -> __synth__0

 #   22| self
 #-----|  -> call to z

-#   22| [...]
+#   22| call to []
 #-----|  -> ... = ...

+#   22| -1
+#-----|  -> call to []
+
+#   22| __synth__0
+#-----|  -> -1
+
+#   22| call to bar=
+#-----|  -> __synth__0
+
+#   22| __synth__0
+#-----|  -> ...
+
+#   22| ... = ...
+#-----|  -> call to bar=
+
+#   22| __synth__0
+#-----|  -> __synth__0
+
+#   22| [...]
+#-----|  -> * ...
+
+#   22| ... = ...
+#-----|  -> x
+
+#   22| * ...
+#-----|  -> ... = ...
+
+#   22| __synth__0
+#-----|  -> 1
+
 #   22| 1
 #-----|  -> 2

@@ -2417,7 +2570,7 @@ desugar.rb:
 #-----|  -> [...]

 #   25| enter m7
-#-----|  -> x
+#-----|  -> __synth__0

 #   25| m7
 #-----|  -> @x
@@ -2427,27 +2580,87 @@ desugar.rb:
 #   25| exit m7 (normal)
 #-----|  -> exit m7

-#   26| ... = ...
+#   26| x
+#-----|  -> __synth__0
+
+#   26| ...
 #-----|  -> exit m7 (normal)

-#   26| (..., ...)
+#   26| ... = ...
+#-----|  -> __synth__0
+
+#   26| call to []
+#-----|  -> ... = ...
+
+#   26| 0
+#-----|  -> call to []
+
+#   26| ...
+#-----|  -> ...
+
+#   26| __synth__0
+#-----|  -> 0
+
+#   26| call to []
+#-----|  -> * ...
+
+#   26| 1
+#-----|  -> call to []
+
+#   26| __synth__0
 #-----|  -> 1

-#   26| x
+#   26| ... = ...
 #-----|  -> y

-#   26| (..., ...)
-#-----|  -> (..., ...)
+#   26| * ...
+#-----|  -> ... = ...
+
+#   26| __synth__0
+#-----|  -> __synth__0

 #   26| y
+#-----|  -> __synth__0
+
+#   26| ... = ...
 #-----|  -> z

+#   26| call to []
+#-----|  -> ... = ...
+
+#   26| 0
+#-----|  -> call to []
+
+#   26| __synth__0
+#-----|  -> 0
+
 #   26| z
-#-----|  -> (..., ...)
+#-----|  -> __synth__0
+
+#   26| ... = ...
+#-----|  -> ...
+
+#   26| call to []
+#-----|  -> ... = ...
+
+#   26| 1
+#-----|  -> call to []
+
+#   26| __synth__0
+#-----|  -> 1

 #   26| [...]
+#-----|  -> * ...
+
+#   26| ... = ...
+#-----|  -> x
+
+#   26| * ...
 #-----|  -> ... = ...

+#   26| __synth__0
+#-----|  -> 1
+
 #   26| 1
 #-----|  -> 2

--- a/ql/test/library-tests/variables/ssa.expected
+++ b/ql/test/library-tests/variables/ssa.expected
@@ -43,10 +43,12 @@ definition
 | scopes.rb:7:1:7:5 | ... = ... | scopes.rb:7:1:7:1 | a |
 | scopes.rb:9:9:18:3 | <captured> | scopes.rb:7:1:7:1 | a |
 | scopes.rb:11:4:11:9 | ... = ... | scopes.rb:7:1:7:1 | a |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:7:1:7:1 | a |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:7:13:7 | b |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:11:13:11 | c |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:14:13:14 | d |
+| scopes.rb:13:4:13:4 | ... = ... | scopes.rb:7:1:7:1 | a |
+| scopes.rb:13:7:13:7 | ... = ... | scopes.rb:13:7:13:7 | b |
+| scopes.rb:13:10:13:15 | ... = ... | scopes.rb:13:10:13:15 | __synth__0 |
+| scopes.rb:13:11:13:11 | ... = ... | scopes.rb:13:11:13:11 | c |
+| scopes.rb:13:14:13:14 | ... = ... | scopes.rb:13:14:13:14 | d |
+| scopes.rb:13:19:13:32 | ... = ... | scopes.rb:13:4:13:32 | __synth__0 |
 | scopes.rb:27:1:27:5 | ... = ... | scopes.rb:27:1:27:1 | x |
 | scopes.rb:42:2:42:9 | ... = ... | scopes.rb:42:2:42:4 | var |
 | scopes.rb:46:5:46:13 | ... = ... | scopes.rb:46:5:46:8 | var2 |
@@ -128,10 +130,15 @@ read
 | scopes.rb:9:9:18:3 | <captured> | scopes.rb:7:1:7:1 | a | scopes.rb:10:9:10:9 | a |
 | scopes.rb:9:9:18:3 | <captured> | scopes.rb:7:1:7:1 | a | scopes.rb:11:4:11:4 | a |
 | scopes.rb:11:4:11:9 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:12:9:12:9 | a |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:14:9:14:9 | a |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:7:13:7 | b | scopes.rb:15:9:15:9 | b |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:11:13:11 | c | scopes.rb:16:9:16:9 | c |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:14:13:14 | d | scopes.rb:17:9:17:9 | d |
+| scopes.rb:13:4:13:4 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:14:9:14:9 | a |
+| scopes.rb:13:7:13:7 | ... = ... | scopes.rb:13:7:13:7 | b | scopes.rb:15:9:15:9 | b |
+| scopes.rb:13:10:13:15 | ... = ... | scopes.rb:13:10:13:15 | __synth__0 | scopes.rb:13:11:13:11 | __synth__0 |
+| scopes.rb:13:10:13:15 | ... = ... | scopes.rb:13:10:13:15 | __synth__0 | scopes.rb:13:14:13:14 | __synth__0 |
+| scopes.rb:13:11:13:11 | ... = ... | scopes.rb:13:11:13:11 | c | scopes.rb:16:9:16:9 | c |
+| scopes.rb:13:14:13:14 | ... = ... | scopes.rb:13:14:13:14 | d | scopes.rb:17:9:17:9 | d |
+| scopes.rb:13:19:13:32 | ... = ... | scopes.rb:13:4:13:32 | __synth__0 | scopes.rb:13:4:13:4 | __synth__0 |
+| scopes.rb:13:19:13:32 | ... = ... | scopes.rb:13:4:13:32 | __synth__0 | scopes.rb:13:7:13:7 | __synth__0 |
+| scopes.rb:13:19:13:32 | ... = ... | scopes.rb:13:4:13:32 | __synth__0 | scopes.rb:13:10:13:15 | __synth__0 |
 | scopes.rb:27:1:27:5 | ... = ... | scopes.rb:27:1:27:1 | x | scopes.rb:28:8:28:8 | x |
 | scopes.rb:27:1:27:5 | ... = ... | scopes.rb:27:1:27:1 | x | scopes.rb:31:10:31:10 | x |
 | scopes.rb:27:1:27:5 | ... = ... | scopes.rb:27:1:27:1 | x | scopes.rb:34:7:34:7 | x |
@@ -209,10 +216,12 @@ firstRead
 | scopes.rb:7:1:7:5 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:8:6:8:6 | a |
 | scopes.rb:9:9:18:3 | <captured> | scopes.rb:7:1:7:1 | a | scopes.rb:10:9:10:9 | a |
 | scopes.rb:11:4:11:9 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:12:9:12:9 | a |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:14:9:14:9 | a |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:7:13:7 | b | scopes.rb:15:9:15:9 | b |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:11:13:11 | c | scopes.rb:16:9:16:9 | c |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:14:13:14 | d | scopes.rb:17:9:17:9 | d |
+| scopes.rb:13:4:13:4 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:14:9:14:9 | a |
+| scopes.rb:13:7:13:7 | ... = ... | scopes.rb:13:7:13:7 | b | scopes.rb:15:9:15:9 | b |
+| scopes.rb:13:10:13:15 | ... = ... | scopes.rb:13:10:13:15 | __synth__0 | scopes.rb:13:11:13:11 | __synth__0 |
+| scopes.rb:13:11:13:11 | ... = ... | scopes.rb:13:11:13:11 | c | scopes.rb:16:9:16:9 | c |
+| scopes.rb:13:14:13:14 | ... = ... | scopes.rb:13:14:13:14 | d | scopes.rb:17:9:17:9 | d |
+| scopes.rb:13:19:13:32 | ... = ... | scopes.rb:13:4:13:32 | __synth__0 | scopes.rb:13:4:13:4 | __synth__0 |
 | scopes.rb:27:1:27:5 | ... = ... | scopes.rb:27:1:27:1 | x | scopes.rb:28:8:28:8 | x |
 | scopes.rb:42:2:42:9 | ... = ... | scopes.rb:42:2:42:4 | var | scopes.rb:44:5:44:7 | var |
 | scopes.rb:46:5:46:13 | ... = ... | scopes.rb:46:5:46:8 | var2 | scopes.rb:47:5:47:8 | var2 |
@@ -280,10 +289,12 @@ lastRead
 | scopes.rb:7:1:7:5 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:8:6:8:6 | a |
 | scopes.rb:9:9:18:3 | <captured> | scopes.rb:7:1:7:1 | a | scopes.rb:11:4:11:4 | a |
 | scopes.rb:11:4:11:9 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:12:9:12:9 | a |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:14:9:14:9 | a |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:7:13:7 | b | scopes.rb:15:9:15:9 | b |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:11:13:11 | c | scopes.rb:16:9:16:9 | c |
-| scopes.rb:13:4:13:32 | ... = ... | scopes.rb:13:14:13:14 | d | scopes.rb:17:9:17:9 | d |
+| scopes.rb:13:4:13:4 | ... = ... | scopes.rb:7:1:7:1 | a | scopes.rb:14:9:14:9 | a |
+| scopes.rb:13:7:13:7 | ... = ... | scopes.rb:13:7:13:7 | b | scopes.rb:15:9:15:9 | b |
+| scopes.rb:13:10:13:15 | ... = ... | scopes.rb:13:10:13:15 | __synth__0 | scopes.rb:13:14:13:14 | __synth__0 |
+| scopes.rb:13:11:13:11 | ... = ... | scopes.rb:13:11:13:11 | c | scopes.rb:16:9:16:9 | c |
+| scopes.rb:13:14:13:14 | ... = ... | scopes.rb:13:14:13:14 | d | scopes.rb:17:9:17:9 | d |
+| scopes.rb:13:19:13:32 | ... = ... | scopes.rb:13:4:13:32 | __synth__0 | scopes.rb:13:10:13:15 | __synth__0 |
 | scopes.rb:27:1:27:5 | ... = ... | scopes.rb:27:1:27:1 | x | scopes.rb:37:5:37:5 | x |
 | scopes.rb:42:2:42:9 | ... = ... | scopes.rb:42:2:42:4 | var | scopes.rb:44:5:44:7 | var |
 | scopes.rb:46:5:46:13 | ... = ... | scopes.rb:46:5:46:8 | var2 | scopes.rb:47:5:47:8 | var2 |
@@ -317,6 +328,9 @@ adjacentReads
 | parameters.rb:7:26:7:31 | pizzas | parameters.rb:7:26:7:31 | pizzas | parameters.rb:8:6:8:11 | pizzas | parameters.rb:11:14:11:19 | pizzas |
 | parameters.rb:25:15:25:18 | name | parameters.rb:25:15:25:18 | name | parameters.rb:25:40:25:43 | name | parameters.rb:26:8:26:11 | name |
 | scopes.rb:9:9:18:3 | <captured> | scopes.rb:7:1:7:1 | a | scopes.rb:10:9:10:9 | a | scopes.rb:11:4:11:4 | a |
+| scopes.rb:13:10:13:15 | ... = ... | scopes.rb:13:10:13:15 | __synth__0 | scopes.rb:13:11:13:11 | __synth__0 | scopes.rb:13:14:13:14 | __synth__0 |
+| scopes.rb:13:19:13:32 | ... = ... | scopes.rb:13:4:13:32 | __synth__0 | scopes.rb:13:4:13:4 | __synth__0 | scopes.rb:13:7:13:7 | __synth__0 |
+| scopes.rb:13:19:13:32 | ... = ... | scopes.rb:13:4:13:32 | __synth__0 | scopes.rb:13:7:13:7 | __synth__0 | scopes.rb:13:10:13:15 | __synth__0 |
 | scopes.rb:27:1:27:5 | ... = ... | scopes.rb:27:1:27:1 | x | scopes.rb:28:8:28:8 | x | scopes.rb:31:10:31:10 | x |
 | scopes.rb:27:1:27:5 | ... = ... | scopes.rb:27:1:27:1 | x | scopes.rb:31:10:31:10 | x | scopes.rb:34:7:34:7 | x |
 | scopes.rb:27:1:27:5 | ... = ... | scopes.rb:27:1:27:1 | x | scopes.rb:34:7:34:7 | x | scopes.rb:34:14:34:14 | x |
--- a/ql/test/library-tests/variables/varaccess.expected
+++ b/ql/test/library-tests/variables/varaccess.expected
@@ -215,10 +215,16 @@ explicitWrite
 | scopes.rb:7:1:7:1 | a | scopes.rb:7:1:7:5 | ... = ... |
 | scopes.rb:11:4:11:4 | a | scopes.rb:11:4:11:9 | ... += ... |
 | scopes.rb:11:4:11:4 | a | scopes.rb:11:4:11:9 | ... = ... |
+| scopes.rb:13:4:13:4 | a | scopes.rb:13:4:13:4 | ... = ... |
 | scopes.rb:13:4:13:4 | a | scopes.rb:13:4:13:32 | ... = ... |
 | scopes.rb:13:7:13:7 | b | scopes.rb:13:4:13:32 | ... = ... |
+| scopes.rb:13:7:13:7 | b | scopes.rb:13:7:13:7 | ... = ... |
+| scopes.rb:13:10:13:15 | __synth__0 | scopes.rb:13:10:13:15 | ... = ... |
 | scopes.rb:13:11:13:11 | c | scopes.rb:13:4:13:32 | ... = ... |
+| scopes.rb:13:11:13:11 | c | scopes.rb:13:11:13:11 | ... = ... |
 | scopes.rb:13:14:13:14 | d | scopes.rb:13:4:13:32 | ... = ... |
+| scopes.rb:13:14:13:14 | d | scopes.rb:13:14:13:14 | ... = ... |
+| scopes.rb:13:19:13:32 | __synth__0 | scopes.rb:13:19:13:32 | ... = ... |
 | scopes.rb:21:1:21:7 | $global | scopes.rb:21:1:21:12 | ... = ... |
 | scopes.rb:24:1:24:6 | script | scopes.rb:24:1:24:11 | ... = ... |
 | scopes.rb:27:1:27:1 | x | scopes.rb:27:1:27:5 | ... = ... |
@@ -334,6 +340,11 @@ readAccess
 | scopes.rb:10:9:10:9 | a |
 | scopes.rb:11:4:11:4 | a |
 | scopes.rb:12:9:12:9 | a |
+| scopes.rb:13:4:13:4 | __synth__0 |
+| scopes.rb:13:7:13:7 | __synth__0 |
+| scopes.rb:13:10:13:15 | __synth__0 |
+| scopes.rb:13:11:13:11 | __synth__0 |
+| scopes.rb:13:14:13:14 | __synth__0 |
 | scopes.rb:14:9:14:9 | a |
 | scopes.rb:15:9:15:9 | b |
 | scopes.rb:16:9:16:9 | c |
--- a/ql/test/library-tests/variables/variable.expected
+++ b/ql/test/library-tests/variables/variable.expected
@@ -54,7 +54,9 @@
 | scopes.rb:4:4:4:4 | a |
 | scopes.rb:7:1:7:1 | a |
 | scopes.rb:9:14:9:14 | x |
+| scopes.rb:13:4:13:32 | __synth__0 |
 | scopes.rb:13:7:13:7 | b |
+| scopes.rb:13:10:13:15 | __synth__0 |
 | scopes.rb:13:11:13:11 | c |
 | scopes.rb:13:14:13:14 | d |
 | scopes.rb:24:1:24:6 | script |