Merge #1607

1607: Improve AST Fragment class r=CohenArthur a=CohenArthur

This changes the APIs around creating AST fragments and refactors the class into its own header and source file, hopefully making it easier to use. This will also help creating "unexpanded" AST fragments for proper builtin macro expansion with the new fixed-point algorithm introduced by #1606 

`@liushuyu` pinging you since you've worked extensively with the macro system. Would love your review!

Co-authored-by: Arthur Cohen <arthur.cohen@embecosm.com>

1 files changed, 21 insertions, 21 deletions

diff --git a/gcc/rust/expand/rust-macro-expand.cc b/gcc/rust/expand/rust-macro-expand.cc
index 96b74da..5894434 100644
--- a/gcc/rust/expand/rust-macro-expand.cc
+++ b/gcc/rust/expand/rust-macro-expand.cc
@@ -26,7 +26,7 @@
 #include "rust-early-name-resolver.h"
 
 namespace Rust {
-AST::ASTFragment
+AST::Fragment
 MacroExpander::expand_decl_macro (Location invoc_locus,
 				  AST::MacroInvocData &invoc,
 				  AST::MacroRulesDefinition &rules_def,
@@ -103,7 +103,7 @@ MacroExpander::expand_decl_macro (Location invoc_locus,
       RichLocation r (invoc_locus);
       r.add_range (rules_def.get_locus ());
       rust_error_at (r, "Failed to match any rule within macro");
-      return AST::ASTFragment::create_error ();
+      return AST::Fragment::create_error ();
     }
 
   return transcribe_rule (*matched_rule, invoc_token_tree, matched_fragments,
@@ -139,7 +139,7 @@ MacroExpander::expand_invoc (AST::MacroInvocation &invoc, bool has_semicolon)
   //      - else is unreachable
   //  - derive container macro - unreachable
 
-  auto fragment = AST::ASTFragment::create_error ();
+  auto fragment = AST::Fragment::create_error ();
   invoc_data.set_expander (this);
 
   // lookup the rules
@@ -707,7 +707,7 @@ MacroExpander::match_repetition (Parser<MacroInvocLexer> &parser,
 /**
  * Helper function to refactor calling a parsing function 0 or more times
  */
-static AST::ASTFragment
+static AST::Fragment
 parse_many (Parser<MacroInvocLexer> &parser, TokenId &delimiter,
 	    std::function<AST::SingleASTNode ()> parse_fn)
 {
@@ -723,13 +723,13 @@ parse_many (Parser<MacroInvocLexer> &parser, TokenId &delimiter,
 	  for (auto err : parser.get_errors ())
 	    err.emit_error ();
 
-	  return AST::ASTFragment::create_error ();
+	  return AST::Fragment::create_error ();
 	}
 
       nodes.emplace_back (std::move (node));
     }
 
-  return AST::ASTFragment (std::move (nodes));
+  return AST::Fragment::complete (std::move (nodes));
 }
 
 /**
@@ -738,7 +738,7 @@ parse_many (Parser<MacroInvocLexer> &parser, TokenId &delimiter,
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_items (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
 {
   return parse_many (parser, delimiter, [&parser] () {
@@ -753,7 +753,7 @@ transcribe_many_items (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_ext (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
 {
   return parse_many (parser, delimiter, [&parser] () {
@@ -768,7 +768,7 @@ transcribe_many_ext (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_trait_items (Parser<MacroInvocLexer> &parser,
 			     TokenId &delimiter)
 {
@@ -784,7 +784,7 @@ transcribe_many_trait_items (Parser<MacroInvocLexer> &parser,
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_impl_items (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
 {
   return parse_many (parser, delimiter, [&parser] () {
@@ -799,7 +799,7 @@ transcribe_many_impl_items (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
  * @param parser Parser to extract items from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_trait_impl_items (Parser<MacroInvocLexer> &parser,
 				  TokenId &delimiter)
 {
@@ -815,7 +815,7 @@ transcribe_many_trait_impl_items (Parser<MacroInvocLexer> &parser,
  * @param parser Parser to extract statements from
  * @param delimiter Id of the token on which parsing should stop
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_many_stmts (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
 {
   auto restrictions = ParseRestrictions ();
@@ -835,12 +835,12 @@ transcribe_many_stmts (Parser<MacroInvocLexer> &parser, TokenId &delimiter)
  *
  * @param parser Parser to extract statements from
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_expression (Parser<MacroInvocLexer> &parser)
 {
   auto expr = parser.parse_expr ();
 
-  return AST::ASTFragment ({std::move (expr)});
+  return AST::Fragment::complete ({std::move (expr)});
 }
 
 /**
@@ -848,17 +848,17 @@ transcribe_expression (Parser<MacroInvocLexer> &parser)
  *
  * @param parser Parser to extract statements from
  */
-static AST::ASTFragment
+static AST::Fragment
 transcribe_type (Parser<MacroInvocLexer> &parser)
 {
   auto type = parser.parse_type (true);
   for (auto err : parser.get_errors ())
     err.emit_error ();
 
-  return AST::ASTFragment ({std::move (type)});
+  return AST::Fragment::complete ({std::move (type)});
 }
 
-static AST::ASTFragment
+static AST::Fragment
 transcribe_on_delimiter (Parser<MacroInvocLexer> &parser, bool semicolon,
 			 AST::DelimType delimiter, TokenId last_token_id)
 {
@@ -868,7 +868,7 @@ transcribe_on_delimiter (Parser<MacroInvocLexer> &parser, bool semicolon,
     return transcribe_expression (parser);
 } // namespace Rust
 
-static AST::ASTFragment
+static AST::Fragment
 transcribe_context (MacroExpander::ContextType ctx,
 		    Parser<MacroInvocLexer> &parser, bool semicolon,
 		    AST::DelimType delimiter, TokenId last_token_id)
@@ -929,7 +929,7 @@ tokens_to_str (std::vector<std::unique_ptr<AST::Token>> &tokens)
   return str;
 }
 
-AST::ASTFragment
+AST::Fragment
 MacroExpander::transcribe_rule (
   AST::MacroRule &match_rule, AST::DelimTokenTree &invoc_token_tree,
   std::map<std::string, MatchedFragmentContainer> &matched_fragments,
@@ -951,7 +951,7 @@ MacroExpander::transcribe_rule (
   rust_debug ("substituted tokens: %s",
 	      tokens_to_str (substituted_tokens).c_str ());
 
-  // parse it to an ASTFragment
+  // parse it to an Fragment
   MacroInvocLexer lex (std::move (substituted_tokens));
   Parser<MacroInvocLexer> parser (lex);
 
@@ -994,7 +994,7 @@ MacroExpander::transcribe_rule (
     {
       for (auto &err : parser.get_errors ())
 	rust_error_at (err.locus, "%s", err.message.c_str ());
-      return AST::ASTFragment::create_error ();
+      return AST::Fragment::create_error ();
     }
 
   // are all the tokens used?