Swift: move BindingPattern to the hidden AST

swift/ql/lib/codeql/swift/controlflow/internal/Completion.qll

@@ -222,7 +222,7 @@ predicate catchMatchingPattern(DoCatchStmt s, CaseStmt c, Pattern pattern) {
 
 /** Holds if `sub` is a subpattern of `p`. */
 private predicate isSubPattern(Pattern p, Pattern sub) {
-  sub = p.(BindingPattern).getSubPattern().getFullyUnresolved()
+  sub = p.(BindingPattern).getResolveStep()
   or
   sub = p.(EnumElementPattern).getSubPattern().getFullyUnresolved()
   or
@@ -260,8 +260,6 @@ private string getPatternValue(Pattern p) {
 private predicate isIrrefutableMatch(Pattern p) {
   (p instanceof NamedPattern or p instanceof AnyPattern)
   or
-  isIrrefutableMatch(p.(BindingPattern).getSubPattern().getFullyUnresolved())
-  or
   isIrrefutableMatch(p.(TypedPattern).getSubPattern().getFullyUnresolved())
   or
   // A pattern hidden underneath a conversion is also an irrefutable pattern.

swift/ql/lib/codeql/swift/controlflow/internal/ControlFlowGraphImpl.qll

@@ -897,21 +897,12 @@ module Patterns {
     }
   }
 
-  private class BindingTree extends AstPostOrderTree {
+  private class BindingTree extends AstStandardPostOrderTree {
     override BindingPattern ast;
 
-    final override predicate propagatesAbnormal(ControlFlowElement n) {
-      n.asAstNode() = ast.getSubPattern().getFullyUnresolved()
-    }
-
-    final override predicate first(ControlFlowElement n) {
-      astFirst(ast.getSubPattern().getFullyUnresolved(), n)
-    }
-
-    override predicate succ(ControlFlowElement pred, ControlFlowElement succ, Completion c) {
-      astLast(ast.getSubPattern().getFullyUnresolved(), pred, c) and
-      c.(MatchingCompletion).isMatch() and
-      succ.asAstNode() = ast
+    final override ControlFlowElement getChildElement(int i) {
+      i = 0 and
+      result.asAstNode() = ast.getResolveStep()
     }
   }
 

swift/ql/lib/codeql/swift/elements/pattern/BindingPattern.qll

@@ -1,5 +1,7 @@
 private import codeql.swift.generated.pattern.BindingPattern
 
 class BindingPattern extends Generated::BindingPattern {
+  final override Pattern getResolveStep() { result = getImmediateSubPattern() }
+
   override string toString() { result = "let ..." }
 }

swift/ql/test/extractor-tests/statements/ConditionElements.expected

@@ -1,7 +1,7 @@
 | statements.swift:3:8:3:13 | ... .==(_:_:) ... | statements.swift:3:8:3:13 | ... .==(_:_:) ... |
 | statements.swift:10:17:10:24 | ... .<(_:_:) ... | statements.swift:10:18:10:22 | ... .<(_:_:) ... |
 | statements.swift:39:9:39:14 | ... .!=(_:_:) ... | statements.swift:39:9:39:14 | ... .!=(_:_:) ... |
-| statements.swift:65:4:65:19 | let ... = ...  | statements.swift:65:9:65:15 | let ... |
-| statements.swift:65:4:65:19 | let ... = ...  | statements.swift:65:19:65:19 | x |
+| statements.swift:65:4:65:19 | let ...? = ...  | statements.swift:65:13:65:15 | let ...? |
+| statements.swift:65:4:65:19 | let ...? = ...  | statements.swift:65:19:65:19 | x |
 | statements.swift:67:4:67:20 | .some(...) = ...  | statements.swift:67:9:67:16 | .some(...) |
 | statements.swift:67:4:67:20 | .some(...) = ...  | statements.swift:67:20:67:20 | x |

swift/ql/test/library-tests/ast/PrintAst.expected

@@ -180,8 +180,8 @@ cfg.swift:
 #   35|           getPattern(): [IsPattern] ... is ...
 #   35|             getSubPattern(): [EnumElementPattern] .error3(...)
 #   35|               getSubPattern(): [TuplePattern] (...)
-#   35|                 getElement(0): [BindingPattern] let ...
-#   35|                   getSubPattern(): [NamedPattern] withParam
+#   35|                 getElement(0): [NamedPattern] withParam
+#   35|                 getElement(0).getFullyUnresolved(): [BindingPattern] let ...
 #   37|       getCatch(2): [CaseStmt] case ...
 #   37|         getBody(): [BraceStmt] { ... }
 #   38|           getElement(0): [CallExpr] call to print(_:separator:terminator:)
@@ -239,9 +239,9 @@ cfg.swift:
 #   40|               getExpr(): [DefaultArgumentExpr] default separator
 #   40|             getArgument(2): [Argument] terminator: default terminator
 #   40|               getExpr(): [DefaultArgumentExpr] default terminator
-#   39|         getLabel(0): [CaseLabelItem] let ...
-#   39|           getPattern(): [BindingPattern] let ...
-#   39|             getSubPattern(): [NamedPattern] error
+#   39|         getLabel(0): [CaseLabelItem] error
+#   39|           getPattern(): [NamedPattern] error
+#   39|           getPattern().getFullyUnresolved(): [BindingPattern] let ...
 #   42|     getElement(1): [ReturnStmt] return ...
 #   42|       getResult(): [IntegerLiteralExpr] 0
 #   35| [ConcreteVarDecl] withParam
@@ -803,9 +803,9 @@ cfg.swift:
 #  156|       getCondition(): [StmtCondition] StmtCondition
 #  156|         getElement(0): [ConditionElement] .some(...) = ... 
 #  156|           getPattern(): [EnumElementPattern] .some(...)
-#  156|             getSubPattern(): [BindingPattern] let ...
-#  156|               getSubPattern(): [NamedPattern] x
+#  156|             getSubPattern(): [NamedPattern] x
 #  156|             getSubPattern().getFullyUnresolved(): [ParenPattern] (...)
+#  156|               getImmediateSubPattern(): [BindingPattern] let ...
 #  156|           getInitializer(): [DeclRefExpr] xOptional
 #  156|       getThen(): [BraceStmt] { ... }
 #  157|         getElement(0): [ReturnStmt] return ...
@@ -5375,11 +5375,11 @@ patterns.swift:
 #   12|       getCase(0): [CaseStmt] case ...
 #   12|         getBody(): [BraceStmt] { ... }
 #   12|           getElement(0): [StringLiteralExpr] binding
-#   12|         getLabel(0): [CaseLabelItem] let ...
-#   12|           getPattern(): [BindingPattern] let ...
-#   12|             getSubPattern(): [TuplePattern] (...)
-#   12|               getElement(0): [NamedPattern] xx
-#   12|               getElement(1): [NamedPattern] yy
+#   12|         getLabel(0): [CaseLabelItem] (...)
+#   12|           getPattern(): [TuplePattern] (...)
+#   12|             getElement(0): [NamedPattern] xx
+#   12|             getElement(1): [NamedPattern] yy
+#   12|           getPattern().getFullyUnresolved(): [BindingPattern] let ...
 #   15|     getElement(3): [SwitchStmt] switch 3 { ... }
 #   15|       getExpr(): [IntegerLiteralExpr] 3
 #   16|       getCase(0): [CaseStmt] case ...
@@ -5424,12 +5424,12 @@ patterns.swift:
 #   28|       getCase(1): [CaseStmt] case ...
 #   28|         getBody(): [BraceStmt] { ... }
 #   28|           getElement(0): [DeclRefExpr] i
-#   28|         getLabel(0): [CaseLabelItem] let ...
-#   28|           getPattern(): [BindingPattern] let ...
-#   28|             getSubPattern(): [EnumElementPattern] .baz(...)
-#   28|               getSubPattern(): [TuplePattern] (...)
-#   28|                 getElement(0): [NamedPattern] i
-#   28|                 getElement(1): [NamedPattern] s
+#   28|         getLabel(0): [CaseLabelItem] .baz(...)
+#   28|           getPattern(): [EnumElementPattern] .baz(...)
+#   28|             getSubPattern(): [TuplePattern] (...)
+#   28|               getElement(0): [NamedPattern] i
+#   28|               getElement(1): [NamedPattern] s
+#   28|           getPattern().getFullyUnresolved(): [BindingPattern] let ...
 #   31|     getElement(8): [PatternBindingDecl] var ... = ...
 #   31|       getInit(0): [NilLiteralExpr] nil
 #   31|       getPattern(0): [TypedPattern] ... as ...
@@ -5442,10 +5442,10 @@ patterns.swift:
 #   34|       getCase(0): [CaseStmt] case ...
 #   34|         getBody(): [BraceStmt] { ... }
 #   34|           getElement(0): [DeclRefExpr] n
-#   34|         getLabel(0): [CaseLabelItem] let ...
-#   34|           getPattern(): [BindingPattern] let ...
-#   34|             getSubPattern(): [OptionalSomePattern] let ...?
-#   34|               getSubPattern(): [NamedPattern] n
+#   34|         getLabel(0): [CaseLabelItem] let ...?
+#   34|           getPattern(): [OptionalSomePattern] let ...?
+#   34|             getSubPattern(): [NamedPattern] n
+#   34|           getPattern().getFullyUnresolved(): [BindingPattern] let ...
 #   35|       getCase(1): [CaseStmt] case ...
 #   35|         getBody(): [BraceStmt] { ... }
 #   35|           getElement(0): [StringLiteralExpr] none
@@ -5470,11 +5470,11 @@ patterns.swift:
 #   42|       getCase(1): [CaseStmt] case ...
 #   42|         getBody(): [BraceStmt] { ... }
 #   42|           getElement(0): [StringLiteralExpr] as pattern
-#   42|         getLabel(0): [CaseLabelItem] let ...
-#   42|           getPattern(): [BindingPattern] let ...
-#   42|             getSubPattern(): [IsPattern] ... is ...
-#   42|               getCastTypeRepr(): [TypeRepr] String
-#   42|               getSubPattern(): [NamedPattern] x
+#   42|         getLabel(0): [CaseLabelItem] ... is ...
+#   42|           getPattern(): [IsPattern] ... is ...
+#   42|             getCastTypeRepr(): [TypeRepr] String
+#   42|             getSubPattern(): [NamedPattern] x
+#   42|           getPattern().getFullyUnresolved(): [BindingPattern] let ...
 #   43|       getCase(2): [CaseStmt] case ...
 #   43|         getBody(): [BraceStmt] { ... }
 #   43|           getElement(0): [StringLiteralExpr] other
@@ -5621,9 +5621,9 @@ statements.swift:
 #   22|               getExpr(): [DefaultArgumentExpr] default separator
 #   22|             getArgument(2): [Argument] terminator: default terminator
 #   22|               getExpr(): [DefaultArgumentExpr] default terminator
-#   21|         getLabel(0): [CaseLabelItem] let ...
-#   21|           getPattern(): [BindingPattern] let ...
-#   21|             getSubPattern(): [NamedPattern] error
+#   21|         getLabel(0): [CaseLabelItem] error
+#   21|           getPattern(): [NamedPattern] error
+#   21|           getPattern().getFullyUnresolved(): [BindingPattern] let ...
 #   25|     getElement(7): [DoCatchStmt] do { ... } catch { ... }
 #   25|       getBody(): [BraceStmt] { ... }
 #   26|         getElement(0): [TryExpr] try ...
@@ -5660,9 +5660,9 @@ statements.swift:
 #   30|               getExpr(): [DefaultArgumentExpr] default separator
 #   30|             getArgument(2): [Argument] terminator: default terminator
 #   30|               getExpr(): [DefaultArgumentExpr] default terminator
-#   29|         getLabel(0): [CaseLabelItem] let ...
-#   29|           getPattern(): [BindingPattern] let ...
-#   29|             getSubPattern(): [NamedPattern] error
+#   29|         getLabel(0): [CaseLabelItem] error
+#   29|           getPattern(): [NamedPattern] error
+#   29|           getPattern().getFullyUnresolved(): [BindingPattern] let ...
 #    2| [ConcreteVarDecl] i
 #    2|     Type = Int
 #   21| [ConcreteVarDecl] error
@@ -5884,10 +5884,10 @@ statements.swift:
 #   65|   getBody(): [BraceStmt] { ... }
 #   65|     getElement(0): [IfStmt] if ... then { ... }
 #   65|       getCondition(): [StmtCondition] StmtCondition
-#   65|         getElement(0): [ConditionElement] let ... = ... 
-#   65|           getPattern(): [BindingPattern] let ...
-#   65|             getSubPattern(): [OptionalSomePattern] let ...?
-#   65|               getSubPattern(): [NamedPattern] xx
+#   65|         getElement(0): [ConditionElement] let ...? = ... 
+#   65|           getPattern(): [OptionalSomePattern] let ...?
+#   65|             getSubPattern(): [NamedPattern] xx
+#   65|           getPattern().getFullyUnresolved(): [BindingPattern] let ...
 #   65|           getInitializer(): [DeclRefExpr] x
 #   65|       getThen(): [BraceStmt] { ... }
 #   67| [TopLevelCodeDecl] { ... }

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

@@ -334,7 +334,10 @@ cfg.swift:
 #-----|  -> default separator
 
 #   39| case ...
-#-----|  -> let ...
+#-----|  -> error
+
+#   39| error
+#-----|  -> error
 
 #   39| error
 #-----| match -> let ...
@@ -342,9 +345,6 @@ cfg.swift:
 #   39| let ...
 #-----| match -> print(_:separator:terminator:)
 
-#   39| let ...
-#-----|  -> error
-
 #   40| print(_:separator:terminator:)
 
 #   40| call to print(_:separator:terminator:)