Add some more debugging information (sorbet#3926)

These functions are handy to have in a debugger.

Author: jez

core/Files.h

@@ -19,6 +19,7 @@ class FileRef final {
     FileRef() : _id(0){};
     FileRef(unsigned int id);
 
+    FileRef(FileRef &f) = default;
     FileRef(const FileRef &f) = default;
     FileRef(FileRef &&f) = default;
     FileRef &operator=(const FileRef &f) = default;

core/Loc.cc

@@ -204,6 +204,12 @@ string LocOffsets::showRaw(const Context ctx) const {
 string LocOffsets::showRaw(const MutableContext ctx) const {
     return Loc(ctx.file, *this).showRaw(ctx);
 }
+string LocOffsets::showRaw(const GlobalState &gs, const FileRef file) const {
+    return Loc(file, *this).showRaw(gs);
+}
+string LocOffsets::showRaw() const {
+    return fmt::format("LocOffsets {{beginPos={}, endPos={}}}", beginPos(), endPos());
+}
 
 string Loc::showRaw(const GlobalState &gs) const {
     string_view path;

core/Loc.h

@@ -36,6 +36,8 @@ struct LocOffsets {
 
     std::string showRaw(const Context ctx) const;
     std::string showRaw(const MutableContext ctx) const;
+    std::string showRaw(const GlobalState &gs, const FileRef file) const;
+    std::string showRaw() const;
 };
 CheckSize(LocOffsets, 8, 4);
 

parser/Builder.cc

@@ -68,12 +68,13 @@ string Dedenter::dedent(string_view str) {
 
 class Builder::Impl {
 public:
-    Impl(GlobalState &gs, core::FileRef file) : gs_(gs) {
+    Impl(GlobalState &gs, core::FileRef file) : gs_(gs), file_(file) {
         this->maxOff_ = file.data(gs).source().size();
         foreignNodes_.emplace_back();
     }
 
     GlobalState &gs_;
+    core::FileRef file_;
     u2 uniqueCounter_ = 1;
     u4 maxOff_;
     ruby_parser::base_driver *driver_;