Add support for parsing variables

This adds a reader flag and serdi option for extending a syntax with support
for SPARQL-like variables, for storing things like patterns or simple queries.

8 files changed, 65 insertions, 2 deletions

diff --git a/tests/bad/bad-var.ttl b/tests/bad/bad-var.ttl
new file mode 100644
index 00000000..29b5b008
--- /dev/null
+++ b/tests/bad/bad-var.ttl
@@ -0,0 +1,2 @@
+?s
+	<http://example.org/p> <http://example.org/o> .
diff --git a/tests/bad/manifest.ttl b/tests/bad/manifest.ttl
index e8ecb396..1bcf6611 100644
--- a/tests/bad/manifest.ttl
+++ b/tests/bad/manifest.ttl
@@ -70,6 +70,7 @@
 		<#bad-string>
 		<#bad-subject>
 		<#bad-uri-escape>
+		<#bad-var>
 		<#bad-verb>
 		<#invalid-char-in-local>
 		<#invalid-char-in-prefix>
@@ -394,6 +395,11 @@
 	mf:name "bad-uri-escape" ;
 	mf:action <bad-uri-escape.ttl> .
 
+<#bad-var>
+	rdf:type rdft:TestTurtleNegativeSyntax ;
+	mf:name "bad-var" ;
+	mf:action <bad-var.ttl> .
+
 <#bad-verb>
 	rdf:type rdft:TestTurtleNegativeSyntax ;
 	mf:name "bad-verb" ;
diff --git a/tests/overflow_test.c b/tests/overflow_test.c
index 918f1cc4..847884de 100644
--- a/tests/overflow_test.c
+++ b/tests/overflow_test.c
@@ -24,8 +24,8 @@
 static SerdStatus
 test(SerdWorld* world, SerdSink* sink, const char* str, size_t stack_size)
 {
-	SerdReader* reader =
-		serd_reader_new(world, SERD_TURTLE, 0, sink, stack_size);
+	SerdReader* reader = serd_reader_new(
+	        world, SERD_TURTLE, SERD_READ_VARIABLES, sink, stack_size);
 
 	serd_reader_start_string(reader, str, NULL);
 	const SerdStatus st = serd_reader_read_document(reader);
@@ -54,6 +54,7 @@ main(void)
 	                      {":s :p \"literal\"", sizes + 264},
 	                      {":s :p \"verb\"", sizes + 263},
 	                      {":s :p _:blank .", sizes + 276},
+	                      {":s :p ?o .", sizes + 295},
 	                      {":s :p true .", sizes + 295},
 	                      {":s :p true .", sizes + 329},
 	                      {":s :p \"\"@en .", sizes + 302},
diff --git a/tests/pattern/bad-pattern.nq b/tests/pattern/bad-pattern.nq
new file mode 100644
index 00000000..a7e0c994
--- /dev/null
+++ b/tests/pattern/bad-pattern.nq
@@ -0,0 +1 @@
+<http://example.org/s> ?pµ <http://example.org/o> .
diff --git a/tests/pattern/bad-pattern.ttl b/tests/pattern/bad-pattern.ttl
new file mode 100644
index 00000000..5f3dbfdd
--- /dev/null
+++ b/tests/pattern/bad-pattern.ttl
@@ -0,0 +1,2 @@
+?sµ
+	<http://example.org/p> <http://example.org/o> .
diff --git a/tests/pattern/manifest.ttl b/tests/pattern/manifest.ttl
new file mode 100644
index 00000000..a179a64d
--- /dev/null
+++ b/tests/pattern/manifest.ttl
@@ -0,0 +1,35 @@
+@prefix mf: <http://www.w3.org/2001/sw/DataAccess/tests/test-manifest#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix rdft: <http://www.w3.org/ns/rdftest#> .
+
+<>
+	rdf:type mf:Manifest ;
+	rdfs:comment "Serd pattern syntax test cases" ;
+	mf:entries (
+		<#bad-pattern-nq>
+		<#bad-pattern-ttl>
+		<#test-pattern-nt>
+		<#test-pattern-ttl>
+	) .
+
+<#bad-pattern-nq>
+	rdf:type rdft:TestNQuadsNegativeSyntax ;
+	mf:name "bad-pattern-nq" ;
+	mf:action <bad-pattern.nq> .
+
+<#bad-pattern-ttl>
+	rdf:type rdft:TestTurtleNegativeSyntax ;
+	mf:name "bad-pattern" ;
+	mf:action <bad-pattern.ttl> .
+
+<#test-pattern-nt>
+	rdf:type rdft:TestNTriplesPositiveSyntax ;
+	mf:name "test-pattern-nt" ;
+	mf:action <test-pattern.nt> .
+
+<#test-pattern-ttl>
+	rdf:type rdft:TestTurtleEval ;
+	mf:name "test-pattern" ;
+	mf:action <test-pattern.ttl> ;
+	mf:result <test-pattern.nt> .
diff --git a/tests/pattern/test-pattern.nt b/tests/pattern/test-pattern.nt
new file mode 100644
index 00000000..ddfe6d3c
--- /dev/null
+++ b/tests/pattern/test-pattern.nt
@@ -0,0 +1,6 @@
+?s <http://example.org/p1> <http://example.org/o1> .
+<http://example.org/s> ?p <http://example.org/o1> .
+<http://example.org/s> <http://example.org/p1> ?o .
+<http://example.org/s> <http://example.org/p2> _:b1 .
+_:b1 ?2p <http://example.org/o2> .
+_:b1 <http://example.org/p3> ?_o .
diff --git a/tests/pattern/test-pattern.ttl b/tests/pattern/test-pattern.ttl
new file mode 100644
index 00000000..3742e5ed
--- /dev/null
+++ b/tests/pattern/test-pattern.ttl
@@ -0,0 +1,10 @@
+?s
+	<http://example.org/p1> <http://example.org/o1> .
+
+<http://example.org/s>
+	?p <http://example.org/o1> ;
+	<http://example.org/p1> ?o ;
+	<http://example.org/p2> [
+		?2p <http://example.org/o2> ;
+		<http://example.org/p3> ?_o
+	] .