Fuzzer: SPARQL results: Makes the fuzzers test serialization too

fuzz/Cargo.toml

@@ -9,6 +9,7 @@ edition = "2021"
 cargo-fuzz = true
 
 [dependencies]
+anyhow = "1"
 lazy_static = "1"
 libfuzzer-sys = "0.4"
 spargebra = { path = "../lib/spargebra", features = ["rdf-star", "sep-0006"] }
@@ -16,6 +17,10 @@ sparesults = { path = "../lib/sparesults", features = ["rdf-star"] }
 sparql-smith = { path = "../lib/sparql-smith", features = ["sep-0006"] }
 oxigraph = { path = "../lib" }
 
+[profile.release]
+codegen-units = 1
+debug = true
+
 [workspace]
 
 [[bin]]

fuzz/fuzz_targets/sparql_results_json.rs

@@ -1,15 +1,6 @@
 #![no_main]
 use libfuzzer_sys::fuzz_target;
-use sparesults::{QueryResultsFormat, QueryResultsParser, QueryResultsReader};
+use oxigraph_fuzz::result_format::fuzz_result_format;
+use sparesults::QueryResultsFormat;
 
-fuzz_target!(|data: &[u8]| {
-    let parser = QueryResultsParser::from_format(QueryResultsFormat::Json);
-    if let Ok(QueryResultsReader::Solutions(solutions)) = parser.read_results(data) {
-        for s in solutions {
-            if s.is_err() {
-                // TODO: avoid infinite loop of errors
-                break;
-            }
-        }
-    }
-});
+fuzz_target!(|data: &[u8]| { fuzz_result_format(QueryResultsFormat::Json, data) });

fuzz/fuzz_targets/sparql_results_tsv.rs

@@ -1,10 +1,6 @@
 #![no_main]
 use libfuzzer_sys::fuzz_target;
-use sparesults::{QueryResultsFormat, QueryResultsParser, QueryResultsReader};
+use oxigraph_fuzz::result_format::fuzz_result_format;
+use sparesults::QueryResultsFormat;
 
-fuzz_target!(|data: &[u8]| {
-    let parser = QueryResultsParser::from_format(QueryResultsFormat::Tsv);
-    if let Ok(QueryResultsReader::Solutions(solutions)) = parser.read_results(data) {
-        for _ in solutions {}
-    }
-});
+fuzz_target!(|data: &[u8]| { fuzz_result_format(QueryResultsFormat::Tsv, data) });

fuzz/fuzz_targets/sparql_results_xml.rs

@@ -1,10 +1,6 @@
 #![no_main]
 use libfuzzer_sys::fuzz_target;
-use sparesults::{QueryResultsFormat, QueryResultsParser, QueryResultsReader};
+use oxigraph_fuzz::result_format::fuzz_result_format;
+use sparesults::QueryResultsFormat;
 
-fuzz_target!(|data: &[u8]| {
-    let parser = QueryResultsParser::from_format(QueryResultsFormat::Xml);
-    if let Ok(QueryResultsReader::Solutions(solutions)) = parser.read_results(data) {
-        for _ in solutions {}
-    }
-});
+fuzz_target!(|data: &[u8]| { fuzz_result_format(QueryResultsFormat::Xml, data) });

fuzz/src/lib.rs

@@ -0,0 +1 @@
+pub mod result_format;

fuzz/src/result_format.rs

@@ -0,0 +1,63 @@
+use anyhow::Context;
+use sparesults::{
+    QueryResultsFormat, QueryResultsParser, QueryResultsReader, QueryResultsSerializer,
+};
+
+pub fn fuzz_result_format(format: QueryResultsFormat, data: &[u8]) {
+    let parser = QueryResultsParser::from_format(format);
+    let serializer = QueryResultsSerializer::from_format(format);
+
+    let Ok(reader) = parser.read_results(data) else {
+        return;
+    };
+    match reader {
+        QueryResultsReader::Solutions(solutions) => {
+            let Ok(solutions) = solutions.collect::<Result<Vec<_>, _>>() else {
+                return;
+            };
+
+            // We try to write again
+            let mut writer = serializer
+                .solutions_writer(
+                    Vec::new(),
+                    solutions
+                        .get(0)
+                        .map_or_else(Vec::new, |s| s.variables().to_vec()),
+                )
+                .unwrap();
+            for solution in &solutions {
+                writer.write(solution).unwrap();
+            }
+            let serialized = String::from_utf8(writer.finish().unwrap()).unwrap();
+
+            // And to parse again
+            if let QueryResultsReader::Solutions(roundtrip_solutions) = parser
+                .read_results(serialized.as_bytes())
+                .with_context(|| format!("Parsing {:?}", &serialized))
+                .unwrap()
+            {
+                assert_eq!(
+                    roundtrip_solutions
+                        .collect::<Result<Vec<_>, _>>()
+                        .with_context(|| format!("Parsing {:?}", &serialized))
+                        .unwrap(),
+                    solutions
+                )
+            }
+        }
+        QueryResultsReader::Boolean(value) => {
+            // We try to write again
+            let mut serialized = Vec::new();
+            serializer
+                .write_boolean_result(&mut serialized, value)
+                .unwrap();
+
+            // And to parse again
+            if let QueryResultsReader::Boolean(roundtrip_value) =
+                parser.read_results(serialized.as_slice()).unwrap()
+            {
+                assert_eq!(roundtrip_value, value)
+            }
+        }
+    }
+}