test(xatu): cover parse failures

src/xatu/xatu_test.rs

@@ -1,5 +1,6 @@
 use std::path::PathBuf;
 
+use status::Code;
 use xatu::SourceFile;
 
 fn source_file(path: &str, source: &str) -> SourceFile {
@@ -15,7 +16,7 @@ fn future_sight_reports_clean_sources_as_clean() {
         "clean.nix",
         include_str!("testdata/clean.nix"),
     )])
-    .expect("source should parse");
+    .expect("fixture should parse");
 
     assert!(report.is_clean());
 }
@@ -26,7 +27,7 @@ fn future_sight_reports_empty_inherit_findings() {
         "empty_inherit.nix",
         include_str!("testdata/empty_inherit.nix"),
     )])
-    .expect("source should parse");
+    .expect("fixture should parse");
 
     assert_eq!(1, report.diagnostics.len());
 
@@ -37,3 +38,14 @@ fn future_sight_reports_empty_inherit_findings() {
     );
     assert_eq!("empty_inherit", diagnostic.finding.rule_id);
 }
+
+#[test]
+fn future_sight_rejects_parse_errors() {
+    let error = xatu::future_sight(vec![source_file(
+        "invalid.nix",
+        include_str!("testdata/invalid.nix"),
+    )])
+    .expect_err("fixture should fail to parse");
+
+    assert_eq!(Code::FailedPrecondition, error.code());
+}