transpose: added tests for invalid transpose requests (and fixed them)

src/api/transpose.rs

@@ -164,18 +164,22 @@ impl<'store> Transposable<'store> for ResultTextSelectionSet<'store> {
                                         .transpose(remainder_begin as isize)
                                         .expect("transposition of offset must succeed");
                                 }
-                                relative_offsets.push(relative_offset);
-                                selectors_per_side[side_i].push(SelectorBuilder::TextSelector(
-                                    resource.handle().into(),
-                                    source_offset,
-                                ));
                                 if let Some(remainder) = remainder {
+                                    if remainder.begin() < intersection.begin() {
+                                        //not a valid intersection, skip to the next
+                                        continue;
+                                    }
                                     resegment = true;
                                     //the text selection was not matched/consumed entirely
                                     //add the remainder of the text selection back to the buffer
                                     tselbuffer
                                         .push_front((remainder, remainder.begin() - tsel.begin()));
                                 }
+                                relative_offsets.push(relative_offset);
+                                selectors_per_side[side_i].push(SelectorBuilder::TextSelector(
+                                    resource.handle().into(),
+                                    source_offset,
+                                ));
                                 break;
                             }
                         }
@@ -289,7 +293,14 @@ impl<'store> Transposable<'store> for ResultTextSelectionSet<'store> {
         }
 
         match selectors_per_side[source_side.expect("source side must exist at this point")].len() {
-            0 => unreachable!("sources must have been found at this point"),
+            0 => 
+                Err(StamError::TransposeError(
+                    format!(
+                        "No source fragments were found in the complex transposition {}, unable to transpose",
+                        via.id().unwrap_or("(no-id)"),
+                    ),
+                    "",
+                )),
             1 if config.allow_simple && !config.no_transposition => {
                 //output is a simple transposition
                 builders.push(

tests/api.rs

@@ -2148,6 +2148,35 @@ fn transpose_over_simple_transposition() -> Result<(), StamError> {
     Ok(())
 }
 
+#[test]
+#[cfg(feature = "transpose")]
+fn transpose_over_simple_transposition_invalid() -> Result<(), StamError> {
+    let mut store = setup_example_8()?;
+    store.annotate(
+        AnnotationBuilder::new()
+            .with_id("A3")
+            .with_data("mydataset", "species", "homo sapiens")
+            .with_target(SelectorBuilder::textselector(
+                "humanrights",
+                Offset::simple(0, 9), //"all human"
+            )),
+    )?;
+    let transposition = store.annotation("SimpleTransposition1").or_fail()?;
+    let source = store.annotation("A3").or_fail()?;
+    assert_eq!(
+        source.text_simple(),
+        Some("all human"),
+        "sanity check for source annotation"
+    );
+    let config = TransposeConfig {
+        transposition_id: Some("NewTransposition".to_string()),
+        target_side_ids: vec!["A3t".to_string()],
+        ..Default::default()
+    };
+    assert!(source.transpose(&transposition, config).is_err());
+    Ok(())
+}
+
 #[test]
 #[cfg(feature = "transpose")]
 fn transpose_over_complex_transposition() -> Result<(), StamError> {
@@ -2275,3 +2304,34 @@ fn transpose_over_complex_transposition_with_resegmentation() -> Result<(), Stam
     );
     Ok(())
 }
+
+#[test]
+#[cfg(feature = "transpose")]
+fn transpose_over_complex_transposition_invalid() -> Result<(), StamError> {
+    let mut store = setup_example_8b()?;
+    store.annotate(
+        AnnotationBuilder::new()
+            .with_id("A3")
+            .with_data("mydataset", "species", "homo sapiens")
+            .with_target(SelectorBuilder::textselector(
+                "humanrights",
+                Offset::simple(0, 9), //"all human"
+            )),
+    )?;
+    let transposition = store.annotation("ComplexTransposition1").or_fail()?;
+    let source = store.annotation("A3").or_fail()?;
+    assert_eq!(
+        source.text_simple(),
+        Some("all human"),
+        "sanity check for source annotation"
+    );
+    let config = TransposeConfig {
+        transposition_id: Some("NewTransposition".to_string()),
+        target_side_ids: vec!["A3t".to_string()],
+        ..Default::default()
+    };
+    let result = source.transpose(&transposition, config);
+    eprintln!("{:#?}", result);
+    assert!(result.is_err());
+    Ok(())
+}