Variable should stay not bound in subqueries even if they are bound in the parent query

Closes #261
2 years ago · d16033ba66
parent becb64b80b
commit d16033ba66
4 changed files with 56 additions and 17 deletions
--- a/lib/src/sparql/eval.rs
+++ b/lib/src/sparql/eval.rs
@ -531,23 +531,32 @@ impl SimpleEvaluator {
                let mapping = mapping.clone();
                Rc::new(move |from| {
                    let mapping = mapping.clone();
-                    // We map forward the "from" values to make sure we join wit them
-                    let mut inner_from = EncodedTuple::with_capacity(mapping.len());
-                    for (input_key, output_key) in mapping.iter() {
-                        if let Some(value) = from.get(*output_key) {
-                            inner_from.set(*input_key, value.clone());
-                        }
-                    }
-                    Box::new(child(inner_from).map(move |tuple| {
-                        let tuple = tuple?;
-                        let mut output_tuple = from.clone();
-                        for (input_key, output_key) in mapping.iter() {
-                            if let Some(value) = tuple.get(*input_key) {
-                                output_tuple.set(*output_key, value.clone());
-                            }
-                        }
-                        Ok(output_tuple)
-                    }))
+                    Box::new(
+                        child(EncodedTuple::with_capacity(mapping.len())).filter_map(
+                            move |tuple| {
+                                match tuple {
+                                    Ok(tuple) => {
+                                        let mut output_tuple = from.clone();
+                                        for (input_key, output_key) in mapping.iter() {
+                                            if let Some(value) = tuple.get(*input_key) {
+                                                if let Some(existing_value) =
+                                                    output_tuple.get(*output_key)
+                                                {
+                                                    if existing_value != value {
+                                                        return None; // Conflict
+                                                    }
+                                                } else {
+                                                    output_tuple.set(*output_key, value.clone());
+                                                }
+                                            }
+                                        }
+                                        Some(Ok(output_tuple))
+                                    }
+                                    Err(e) => Some(Err(e)),
+                                }
+                            },
+                        ),
+                    )
                })
            }
            PlanNode::Aggregate {
--- a/testsuite/oxigraph-tests/sparql/manifest.ttl
+++ b/testsuite/oxigraph-tests/sparql/manifest.ttl
@ -27,6 +27,7 @@
    :nested_expression
    :order_terms
    :nested_anonymous
+    :unbound_variable_in_subquery
    ) .

 :small_unicode_escape_with_multibytes_char rdf:type mf:NegativeSyntaxTest ;
@ -122,3 +123,9 @@
         [ qt:query  <nested_anonymous.rq> ;
           qt:data   <nested_anonymous.ttl> ] ;
    mf:result  <nested_anonymous.srx> .
+
+:unbound_variable_in_subquery rdf:type mf:QueryEvaluationTest ;
+    mf:name "Variable should stay not bound in subqueries even if they are bound in the parent query" ;
+    mf:action
+         [ qt:query  <unbound_variable_in_subquery.rq> ] ;
+    mf:result  <unbound_variable_in_subquery.srx> .
--- a/testsuite/oxigraph-tests/sparql/unbound_variable_in_subquery.rq
+++ b/testsuite/oxigraph-tests/sparql/unbound_variable_in_subquery.rq
@ -0,0 +1,6 @@
+PREFIX ex: <http://example.com/>
+
+SELECT ?a ?b WHERE {
+    BIND(ex:a as ?a)
+    {SELECT ?b WHERE { BIND(ex:b as ?b) FILTER(!BOUND(?a))}}
+}
--- a/testsuite/oxigraph-tests/sparql/unbound_variable_in_subquery.srx
+++ b/testsuite/oxigraph-tests/sparql/unbound_variable_in_subquery.srx
@ -0,0 +1,17 @@
+<?xml version="1.0"?>
+<sparql xmlns="http://www.w3.org/2005/sparql-results#">
+    <head>
+        <variable name="a"/>
+        <variable name="b"/>
+    </head>
+    <results>
+        <result>
+            <binding name="a">
+                <uri>http://example.com/a</uri>
+            </binding>
+            <binding name="b">
+                <uri>http://example.com/b</uri>
+            </binding>
+        </result>
+    </results>
+</sparql>