[Constraint] Pass solverState indents to ASTPrinter's dump so that AST printed during conjunction attempts are indented correctly.

Author: Amritpan Kaur

include/swift/Sema/Constraint.h

@@ -855,7 +855,8 @@ class Constraint final : public llvm::ilist_node<Constraint>,
   /// Print constraint placed on type and constraint properties.
   ///
   /// \c skipLocator skips printing of locators.
-  void print(llvm::raw_ostream &Out, SourceManager *sm, bool skipLocator = false) const;
+  void print(llvm::raw_ostream &Out, SourceManager *sm, unsigned indent = 0,
+             bool skipLocator = false) const;
 
   SWIFT_DEBUG_DUMPER(dump(SourceManager *SM));
 

include/swift/Sema/ConstraintSystem.h

@@ -6107,7 +6107,7 @@ class DisjunctionChoice {
   bool isSymmetricOperator() const;
   bool isUnaryOperator() const;
 
-  void print(llvm::raw_ostream &Out, SourceManager *SM) const {
+  void print(llvm::raw_ostream &Out, SourceManager *SM, unsigned indent = 0) const {
     Out << "disjunction choice ";
     Choice->print(Out, SM);
   }
@@ -6139,9 +6139,9 @@ class ConjunctionElement {
 
   ConstraintLocator *getLocator() const { return Element->getLocator(); }
 
-  void print(llvm::raw_ostream &Out, SourceManager *SM) const {
+  void print(llvm::raw_ostream &Out, SourceManager *SM, unsigned indent) const {
     Out << "conjunction element ";
-    Element->print(Out, SM);
+    Element->print(Out, SM, indent);
   }
 
 private:
@@ -6176,7 +6176,7 @@ class TypeVariableBinding {
   Optional<std::pair<ConstraintFix *, unsigned>>
   fixForHole(ConstraintSystem &cs) const;
 
-  void print(llvm::raw_ostream &Out, SourceManager *) const {
+  void print(llvm::raw_ostream &Out, SourceManager *, unsigned indent) const {
     PrintOptions PO;
     PO.PrintTypesForDebugging = true;
     Out << "type variable " << TypeVar->getString(PO)

lib/Sema/CSStep.h

@@ -519,7 +519,7 @@ template <typename P> class BindingStep : public SolverStep {
       if (CS.isDebugMode()) {
         auto &log = getDebugLogger();
         log << "(attempting ";
-        choice->print(log, &CS.getASTContext().SourceMgr);
+        choice->print(log, &CS.getASTContext().SourceMgr, CS.solverState->depth * 2 + 2);
         log << '\n';
       }
 

lib/Sema/Constraint.cpp

@@ -322,7 +322,7 @@ Constraint *Constraint::clone(ConstraintSystem &cs) const {
   llvm_unreachable("Unhandled ConstraintKind in switch.");
 }
 
-void Constraint::print(llvm::raw_ostream &Out, SourceManager *sm, bool skipLocator) const {
+void Constraint::print(llvm::raw_ostream &Out, SourceManager *sm, unsigned indent, bool skipLocator) const {
   // Print all type variables as $T0 instead of _ here.
   PrintOptions PO;
   PO.PrintTypesForDebugging = true;
@@ -383,11 +383,11 @@ void Constraint::print(llvm::raw_ostream &Out, SourceManager *sm, bool skipLocat
       Out << "pattern binding element @ ";
       Out << patternBindingElt->getIndex() << " : ";
       Out << '\n';
-      patternBinding->getPattern(patternBindingElt->getIndex())->dump(Out);
+      patternBinding->getPattern(patternBindingElt->getIndex())->dump(Out, indent);
     } else {
       Out << "syntactic element ";
       Out << '\n';
-      element.dump(Out);
+      element.dump(Out, indent);
     }
 
     return;