Improve the dumping of ProtocolConformances, Substitutions,

and ErasureExpr.

Author: rjmccall

include/swift/AST/ProtocolConformance.h

@@ -286,6 +286,7 @@ class alignas(1 << DeclAlignInBits) ProtocolConformance {
   AbstractStorageDecl *getBehaviorDecl() const;
 
   void dump() const;
+  void dump(llvm::raw_ostream &out, unsigned indent = 0) const;
 
 private:
   friend class Substitution;

include/swift/AST/ProtocolConformanceRef.h

@@ -20,6 +20,10 @@
 #include "llvm/ADT/PointerUnion.h"
 #include "swift/AST/TypeAlignments.h"
 
+namespace llvm {
+  class raw_ostream;
+}
+
 namespace swift {
 
 /// A ProtocolConformanceRef is a handle to a protocol conformance which
@@ -80,6 +84,7 @@ class ProtocolConformanceRef {
   ProtocolDecl *getRequirement() const;
 
   void dump() const;
+  void dump(llvm::raw_ostream &out, unsigned indent = 0) const;
 
   bool operator==(ProtocolConformanceRef other) const {
     return Union == other.Union;

include/swift/AST/Substitution.h

@@ -57,6 +57,7 @@ class Substitution {
   void print(llvm::raw_ostream &os,
              const PrintOptions &PO = PrintOptions()) const;
   void dump() const;
+  void dump(llvm::raw_ostream &os, unsigned indent = 0) const;
 
   /// Substitute the replacement and conformance types with the given
   /// substitution vector.

lib/AST/ASTDumper.cpp

@@ -1504,6 +1504,9 @@ class PrintExpr : public ExprVisitor<PrintExpr> {
     PrintPattern(OS, Indent+2).visit(const_cast<Pattern *>(P));
   }
   void printRec(TypeRepr *T);
+  void printRec(ProtocolConformanceRef conf) {
+    conf.dump(OS, Indent + 2);
+  }
 
   static const char *getAccessKindString(AccessKind kind) {
     switch (kind) {
@@ -1868,6 +1871,10 @@ class PrintExpr : public ExprVisitor<PrintExpr> {
   }
   void visitErasureExpr(ErasureExpr *E) {
     printCommon(E, "erasure_expr") << '\n';
+    for (auto conf : E->getConformances()) {
+      printRec(conf);
+      OS << '\n';
+    }
     printRec(E->getSubExpr());
     OS << ')';
   }
@@ -2385,32 +2392,30 @@ void TypeRepr::dump() const {
 }
 
 void Substitution::dump() const {
-  llvm::raw_ostream &os = llvm::errs();
-
-  print(os);
-  os << '\n';
+  dump(llvm::errs());
+}
 
-  if (!Conformance.size()) return;
+void Substitution::dump(llvm::raw_ostream &out, unsigned indent) const {
+  out.indent(indent);
+  print(out);
+  out << '\n';
 
-  os << '[';
-  bool first = true;
   for (auto &c : Conformance) {
-    if (first) {
-      first = false;
-    } else {
-      os << ' ';
-    }
-    c.dump();
+    c.dump(out, indent + 2);
   }
-  os << " ]";
 }
 
 void ProtocolConformanceRef::dump() const {
-  llvm::raw_ostream &os = llvm::errs();
+  dump(llvm::errs());
+}
+
+void ProtocolConformanceRef::dump(llvm::raw_ostream &out,
+                                  unsigned indent) const {
   if (isConcrete()) {
-    getConcrete()->printName(os);
+    getConcrete()->dump(out, indent);
   } else {
-    os << "abstract:" << getAbstract()->getName();
+    out.indent(indent) << "(abstract_conformance protocol="
+                       << getAbstract()->getName() << ')';
   }
 }
 
@@ -2423,10 +2428,45 @@ void swift::dump(const ArrayRef<Substitution> &subs) {
 }
 
 void ProtocolConformance::dump() const {
-  // FIXME: If we ever write a full print() method for ProtocolConformance, use
-  // that.
-  printName(llvm::errs());
-  llvm::errs() << '\n';
+  auto &out = llvm::errs();
+  dump(out);
+  out << '\n';
+}
+
+void ProtocolConformance::dump(llvm::raw_ostream &out, unsigned indent) const {
+  auto printCommon = [&](StringRef kind) {
+    out.indent(indent) << '(' << kind << "_conformance type=" << getType()
+                       << " protocol=" << getProtocol()->getName();
+  };
+
+  switch (getKind()) {
+  case ProtocolConformanceKind::Normal:
+    printCommon("normal");
+    // Maybe print information about the conforming context?
+    break;
+
+  case ProtocolConformanceKind::Inherited: {
+    auto conf = cast<InheritedProtocolConformance>(this);
+    printCommon("inherited");
+    out << '\n';
+    conf->getInheritedConformance()->dump(out, indent + 2);
+    break;
+  }
+
+  case ProtocolConformanceKind::Specialized: {
+    auto conf = cast<SpecializedProtocolConformance>(this);
+    printCommon("specialized");
+    out << '\n';
+    for (auto sub : conf->getGenericSubstitutions()) {
+      sub.dump(out, indent + 2);
+      out << '\n';
+    }
+    conf->getGenericConformance()->dump(out, indent + 2);
+    break;
+  }
+  }
+
+  out << ')';
 }
 
 //===----------------------------------------------------------------------===//