From 8c497f0b7ad84daf061ef299ee53741c1bd946a9 Mon Sep 17 00:00:00 2001
From: gluax <jonathan.t.pavlik@gmail.com>
Date: Mon, 19 Apr 2021 13:53:49 -0400
Subject: [PATCH] more test coverage

---
 ast/src/errors/combiner.rs                               | 8 +-------
 ast/src/reducer/canonicalization.rs                      | 9 ++++-----
 .../tests/canonicalization/illegal_array_range_fail.leo  | 4 ++++
 compiler/tests/canonicalization/mod.rs                   | 8 ++++++++
 4 files changed, 17 insertions(+), 12 deletions(-)
 create mode 100644 compiler/tests/canonicalization/illegal_array_range_fail.leo

diff --git a/ast/src/errors/combiner.rs b/ast/src/errors/combiner.rs
index 7c8aa72375..5a1022db27 100644
--- a/ast/src/errors/combiner.rs
+++ b/ast/src/errors/combiner.rs
@@ -35,15 +35,9 @@ impl CombinerError {
         Self::new_from_span(message, span)
     }
 
-    pub fn illegal_compound_array_access(span: &Span) -> Self {
+    pub fn illegal_compound_array_range(span: &Span) -> Self {
         let message = "Illegal compound assignement with array range".to_string();
 
         Self::new_from_span(message, span)
     }
-
-    pub fn illegal_compound_operation(span: &Span) -> Self {
-        let message = "Illegal compound assignment operator =".to_string();
-
-        Self::new_from_span(message, span)
-    }
 }
diff --git a/ast/src/reducer/canonicalization.rs b/ast/src/reducer/canonicalization.rs
index bdba3ab7f8..7237d88d69 100644
--- a/ast/src/reducer/canonicalization.rs
+++ b/ast/src/reducer/canonicalization.rs
@@ -69,7 +69,7 @@ impl Canonicalizer {
                         span: span.clone(),
                     }));
                 }
-                _ => return Err(ReducerError::from(CombinerError::illegal_compound_array_access(&span))),
+                _ => return Err(ReducerError::from(CombinerError::illegal_compound_array_range(&span))),
             }
         }
 
@@ -79,10 +79,9 @@ impl Canonicalizer {
     pub fn compound_operation_converstion(
         &mut self,
         operation: &AssignOperation,
-        span: &Span,
     ) -> Result<BinaryOperation, ReducerError> {
         match operation {
-            AssignOperation::Assign => Err(ReducerError::from(CombinerError::illegal_compound_operation(&span))),
+            AssignOperation::Assign => unreachable!(),
             AssignOperation::Add => Ok(BinaryOperation::Add),
             AssignOperation::Sub => Ok(BinaryOperation::Sub),
             AssignOperation::Mul => Ok(BinaryOperation::Mul),
@@ -550,7 +549,7 @@ impl ReconstructingReducer for Canonicalizer {
                     &assign.span,
                 )?;
                 let right = Box::new(Expression::Binary(binary_expr));
-                let op = self.compound_operation_converstion(&assign.operation, &assign.span)?;
+                let op = self.compound_operation_converstion(&assign.operation)?;
 
                 let new_value = Expression::Binary(BinaryExpression {
                     left,
@@ -573,7 +572,7 @@ impl ReconstructingReducer for Canonicalizer {
                     &assign.span,
                 )?;
                 let right = Box::new(Expression::Value(value_expr));
-                let op = self.compound_operation_converstion(&assign.operation, &assign.span)?;
+                let op = self.compound_operation_converstion(&assign.operation)?;
 
                 let new_value = Expression::Binary(BinaryExpression {
                     left,
diff --git a/compiler/tests/canonicalization/illegal_array_range_fail.leo b/compiler/tests/canonicalization/illegal_array_range_fail.leo
new file mode 100644
index 0000000000..af14957712
--- /dev/null
+++ b/compiler/tests/canonicalization/illegal_array_range_fail.leo
@@ -0,0 +1,4 @@
+function main () {
+  let x = [1u32; 5];
+  x[..2] += 1;
+}
\ No newline at end of file
diff --git a/compiler/tests/canonicalization/mod.rs b/compiler/tests/canonicalization/mod.rs
index fd2db5da3f..f420b2370c 100644
--- a/compiler/tests/canonicalization/mod.rs
+++ b/compiler/tests/canonicalization/mod.rs
@@ -87,3 +87,11 @@ fn test_compound_assignment() {
 
     assert_eq!(expected_ast, ast);
 }
+
+#[test]
+fn test_illegal_array_range_fail() {
+    // Check program is invalid.
+    let program_string = include_str!("illegal_array_range_fail.leo");
+    let program = parse_program(program_string);
+    assert!(program.is_err());
+}