make insert_from_end work correctly

diff --git a/src/prolog/heap_print.rs b/src/prolog/heap_print.rs
index 4c577974bc1e771419db0e6fa61239b87aeb227e..8e1bcc5edefc724c80fe2604bb8790f8f9edf32c 100644 (file)
--- a/src/prolog/heap_print.rs
+++ b/src/prolog/heap_print.rs
@@ -82,7 +82,8 @@ impl HCValueOutputter for PrinterOutputter {
     }
 
     fn insert_from_end(&mut self, idx: usize, c: char) {
-        self.contents.insert(idx, c);
+        let len = self.contents.len();
+        self.contents.insert(len - idx, c);
     }
 
     fn result(self) -> Self::Output {

diff --git a/src/tests.rs b/src/tests.rs
index 9602fba8a3c392fd2b7b50ac06be4f2b93497cd1..a7ae5558bef37d82d4cea118a49ceb91942b7369 100644 (file)
--- a/src/tests.rs
+++ b/src/tests.rs
@@ -51,7 +51,8 @@ impl HCValueOutputter for TestOutputter {
     }
 
     fn insert_from_end(&mut self, idx: usize, c: char) {
-        self.focus.insert(idx, c);
+        let len = self.focus.len();
+        self.focus.insert(len - idx, c);
     }
     
     fn result(self) -> Self::Output {