Simplify streaming API and improve pretty printing

This removes the obligation from the caller to correctly maintain flags to
describe the current anonymous context, instead making the writer handle this
itself as much as possible.  Flags remain for the cases the writer can not
infer from context: the start of anonymous subject and object nodes.

1 files changed, 10 insertions, 15 deletions

diff --git a/src/n3.c b/src/n3.c
index cdb2d9a7..e976edf6 100644
--- a/src/n3.c
+++ b/src/n3.c
@@ -927,7 +927,7 @@ read_anon(SerdReader* reader, ReadContext ctx, bool subject, SerdNode** dest)
 	bool empty;
 	eat_byte_safe(reader, '[');
 	if ((empty = peek_delim(reader, ']'))) {
-		*ctx.flags |= (subject) ? SERD_EMPTY_S : SERD_EMPTY_O;
+		*ctx.flags |= (subject) ? SERD_EMPTY_S : SERD_ANON_O_BEGIN;
 	} else {
 		*ctx.flags |= (subject) ? SERD_ANON_S_BEGIN : SERD_ANON_O_BEGIN;
 		if (peek_delim(reader, '=')) {
@@ -949,21 +949,19 @@ read_anon(SerdReader* reader, ReadContext ctx, bool subject, SerdNode** dest)
 
 	ctx.subject = *dest;
 	if (!empty) {
-		*ctx.flags &= ~(SERD_LIST_CONT);
-		if (!subject) {
-			*ctx.flags |= SERD_ANON_CONT;
-		}
 		bool ate_dot_in_list = false;
 		read_predicateObjectList(reader, ctx, &ate_dot_in_list);
 		if (ate_dot_in_list) {
 			return r_err(reader, SERD_ERR_BAD_SYNTAX, "`.' inside blank\n");
 		}
 		read_ws_star(reader);
-		if (reader->sink->end) {
-			reader->sink->end(reader->sink->handle, *dest);
-		}
 		*ctx.flags = old_flags;
 	}
+
+	if (reader->sink->end && (!subject || !empty)) {
+		reader->sink->end(reader->sink->handle, *dest);
+	}
+
 	return (eat_byte_check(reader, ']') == ']') ? SERD_SUCCESS
 	                                            : SERD_ERR_BAD_SYNTAX;
 }
@@ -1114,9 +1112,8 @@ read_predicateObjectList(SerdReader* reader, ReadContext ctx, bool* ate_dot)
 }
 
 static SerdStatus
-end_collection(SerdReader* reader, ReadContext ctx, SerdStatus st)
+end_collection(SerdReader* reader, SerdStatus st)
 {
-	*ctx.flags &= ~SERD_LIST_CONT;
 	if (!st) {
 		eat_byte_safe(reader, ')');
 	}
@@ -1134,13 +1131,12 @@ read_collection(SerdReader* reader, ReadContext ctx, SerdNode** dest)
 		// subject predicate _:head
 		*ctx.flags |= (end ? 0 : SERD_LIST_O_BEGIN);
 		TRY(st, emit_statement(reader, ctx, *dest));
-		*ctx.flags |= SERD_LIST_CONT;
 	} else {
 		*ctx.flags |= (end ? 0 : SERD_LIST_S_BEGIN);
 	}
 
 	if (end) {
-		return end_collection(reader, ctx, st);
+		return end_collection(reader, st);
 	}
 
 	/* The order of node allocation here is necessarily not in stack order,
@@ -1160,7 +1156,7 @@ read_collection(SerdReader* reader, ReadContext ctx, SerdNode** dest)
 		ctx.predicate = reader->rdf_first;
 		bool ate_dot = false;
 		if ((st = read_object(reader, &ctx, true, &ate_dot)) || ate_dot) {
-			return end_collection(reader, ctx, SERD_FAILURE);
+			return end_collection(reader, SERD_FAILURE);
 		}
 
 		if (!(end = peek_delim(reader, ')'))) {
@@ -1174,7 +1170,6 @@ read_collection(SerdReader* reader, ReadContext ctx, SerdNode** dest)
 		}
 
 		// _:node rdf:rest _:rest
-		*ctx.flags |= SERD_LIST_CONT;
 		ctx.predicate = reader->rdf_rest;
 		TRY(st, emit_statement(reader, ctx, (end ? reader->rdf_nil : rest)));
 
@@ -1183,7 +1178,7 @@ read_collection(SerdReader* reader, ReadContext ctx, SerdNode** dest)
 		node        = ctx.subject;  // invariant
 	}
 
-	return end_collection(reader, ctx, st);
+	return end_collection(reader, st);
 }
 
 static SerdStatus