Parse - Module Loading - Hopefully fix libcore without breaking other crates

2 files changed, 117 insertions, 15 deletions

diff --git a/src/ast/ast.hpp b/src/ast/ast.hpp
index b80b5fb7..493b397c 100644
--- a/src/ast/ast.hpp
+++ b/src/ast/ast.hpp
@@ -517,7 +517,11 @@ public:
     struct FileInfo
     {
         bool    controls_dir = false;
+        bool    force_no_load = false;
+        // Path to this module
         ::std::string   path = "!";
+        // Directory controlled by this module
+        ::std::string   dir = "";
     };
 
     FileInfo    m_file_info;
diff --git a/src/parse/root.cpp b/src/parse/root.cpp
index 9ab84c78..d457d197 100644
--- a/src/parse/root.cpp
+++ b/src/parse/root.cpp
@@ -1513,6 +1513,102 @@ bool Parse_MacroInvocation_Opt(TokenStream& lex,  AST::MacroInvocation& out_inv)
     return true;
 }
 
+#if 0
+namespace {
+    ::AST::Module::FileInfo get_submod_file(
+        Span sp, const ::AST::Module::FileInfo& parent_fileinfo, const ::std::string& new_mod_name, const ::std::string& path_attr,
+        bool is_extern_file, bool is_cfg_disabled
+        )
+    {
+        ::AST::Module::FileInfo rv;
+        TRACE_FUNCTION_F(new_mod_name << ", " << path_attr << ", " << is_extern_file);
+        ::std::string   sub_path;
+        bool    sub_file_controls_dir = true;
+
+        // 1. Determine the base path for the module
+        if( parent_fileinfo.path == "-" ) {
+            if( path_attr.size() ) {
+                ERROR(lex.point_span(), E0000, "Cannot load module from file when reading stdin");
+            }
+            sub_path = "-";
+        }
+        else if( path_attr.size() > 0 )
+        {
+            // #[path] present, add to the parent path
+            sub_path = dirname(parent_fileinfo.path) + path_attr;
+        }
+        else if( mod_fileinfo.controls_dir )
+        {
+            // The parent module is either the crate root, or a `mod.rs` (or otherwise a controller)
+            sub_path = parent_fileinfo.dir + name;
+        }
+        else
+        {
+            sub_path = parent_fileinfo.path;
+            sub_file_controls_dir = false;
+        }
+        DEBUG("Mod '" << name << "', sub_path = " << sub_path);
+
+        rv.path = sub_path;
+        rv.controls_dir = sub_file_controls_dir;
+
+        if( is_cfg_disabled || parent_fileinfo.force_no_load )
+        {
+            rv.force_no_load = true;
+        }
+        if( ! is_extern_file )
+        {
+            // If this is an inline module, set the path to just a directory
+            if( sub_path != "-" ) {
+                rv.path = sub_path + "/";
+                rv.dir = sub_path + "/";
+            }
+            else {
+                rv.path = "-";
+            }
+        }
+        else
+        {
+            if( sub_path == "-" )
+            {
+                ERROR(lex.point_span(), E0000, "Cannot load module from file when reading stdin");
+            }
+            else
+            {
+                ::std::string newpath_dir  = sub_path + "/";
+                ::std::string newpath_file = path_attr.size() > 0 ? sub_path : sub_path + ".rs";
+                DEBUG("newpath_dir = '" << newpath_dir << "', newpath_file = '" << newpath_file << "'");
+                ::std::ifstream ifs_dir (newpath_dir + "mod.rs");
+                ::std::ifstream ifs_file(newpath_file);
+                if( ifs_dir.is_open() && ifs_file.is_open() )
+                {
+                    // Collision
+                    ERROR(lex.point_span(), E0000, "Both modname.rs and modname/mod.rs exist");
+                }
+                else if( ifs_dir.is_open() )
+                {
+                    // Load from dir
+                    rv.path = newpath_dir + "mod.rs";
+                    rv.dir = newpath_dir;
+                }
+                else if( ifs_file.is_open() )
+                {
+                    rv.path = newpath_file;
+                    rv.dir = newpath_dir;
+                    rv.controls_dir = false;
+                }
+                else
+                {
+                    // Can't find file
+                    ERROR(sp, E0000, "Can't find file for '" << name << "' in '" << parent_fileinfo.dir << "'");
+                }
+            }
+        }
+        return rv;
+    }
+}
+#endif
+
 ::AST::Named<::AST::Item> Parse_Mod_Item_S(TokenStream& lex, const AST::Module::FileInfo& mod_fileinfo, const ::AST::Path& mod_path, AST::AttributeList meta_items)
 {
     TRACE_FUNCTION_F("mod_path="<<mod_path<<", meta_items="<<meta_items);
@@ -1828,6 +1924,19 @@ bool Parse_MacroInvocation_Opt(TokenStream& lex,  AST::MacroInvocation& out_inv)
         DEBUG("Sub module '" << name << "'");
         AST::Module submod( mod_path + name );
 
+        // Check #[cfg] and don't load if it fails
+        struct H {
+            static bool check_item_cfg(const ::AST::AttributeList& attrs)
+            {
+                for(const auto& at : attrs.m_items) {
+                    if( at.name() == "cfg" && !check_cfg(at.span(), at) ) {
+                        return false;
+                    }
+                }
+                return true;
+            }
+        };
+
         // Rules for external files (/ path handling):
         // - IF using stdin (path='-') - Disallow and propagate '-' as path
         // - IF a #[path] attribute was passed, allow
@@ -1835,7 +1944,7 @@ bool Parse_MacroInvocation_Opt(TokenStream& lex,  AST::MacroInvocation& out_inv)
         // - else, disallow and set flag
         ::std::string path_attr = (meta_items.has("path") ? meta_items.get("path")->string() : "");
 
-        //submod.m_file_info = get_submod_file(lex.end_span(ps), mod_fileinfo,  name, path_attr, LOOK_AHEAD(lex) == TOK_SEMICOLON);
+        //submod.m_file_info = get_submod_file(lex.end_span(ps), mod_fileinfo,  name, path_attr, LOOK_AHEAD(lex) == TOK_SEMICOLON, H::check_item_cfg(meta_items));
 
         ::std::string   sub_path;
         bool    sub_file_controls_dir = true;
@@ -1863,23 +1972,12 @@ bool Parse_MacroInvocation_Opt(TokenStream& lex,  AST::MacroInvocation& out_inv)
         submod.m_file_info.path = sub_path;
         submod.m_file_info.controls_dir = sub_file_controls_dir;
 
-        // Check #[cfg] and don't load if it fails
-        struct H {
-            static bool check_item_cfg(const ::AST::AttributeList& attrs)
-            {
-                for(const auto& at : attrs.m_items) {
-                    if( at.name() == "cfg" && !check_cfg(at.span(), at) ) {
-                        return false;
-                    }
-                }
-                return true;
-            }
-        };
-
         switch( GET_TOK(tok, lex) )
         {
         case TOK_BRACE_OPEN:
             submod.m_file_info.path = sub_path + "/";
+            // TODO: If cfg fails, just eat the TT until a matching #[cfg]?
+            // - Or, mark the file infor as not being valid (so child modules don't try to load)
             Parse_ModRoot(lex, submod, meta_items);
             GET_CHECK_TOK(tok, lex, TOK_BRACE_CLOSE);
             break;
@@ -1934,7 +2032,7 @@ bool Parse_MacroInvocation_Opt(TokenStream& lex,  AST::MacroInvocation& out_inv)
                 else if( ifs_file.is_open() )
                 {
                     submod.m_file_info.path = newpath_file;
-                    submod.m_file_info.controls_dir = false;
+                    //submod.m_file_info.controls_dir = false;
                 }
                 // TODO: If this is not a controlling file, look in `modname/` for the new module
                 else