Merge pull request #1032 from Zokrates/fail-early-on-complex-value-inequality

Fail at compile time on unsatisfied equality of complex values

changelogs/unreleased/1032-schaeff

@@ -0,0 +1 @@
+Fail at compile time when complex types are known not to be equal

zokrates_cli/examples/compile_errors/assertion_unequal_arrays.zok

@@ -0,0 +1,3 @@
+def main():
+    assert([1f] == [2f])
+    return

zokrates_core/src/static_analysis/zir_propagation.rs

@@ -2,8 +2,8 @@ use crate::zir::result_folder::fold_statement;
 use crate::zir::result_folder::ResultFolder;
 use crate::zir::types::UBitwidth;
 use crate::zir::{
-    BooleanExpression, FieldElementExpression, Identifier, UExpression, UExpressionInner,
-    ZirExpression, ZirProgram, ZirStatement,
+    BooleanExpression, FieldElementExpression, Identifier, RuntimeError, UExpression,
+    UExpressionInner, ZirExpression, ZirProgram, ZirStatement,
 };
 use std::collections::HashMap;
 use std::fmt;
@@ -15,6 +15,7 @@ type Constants<'ast, T> = HashMap<Identifier<'ast>, ZirExpression<'ast, T>>;
 pub enum Error {
     OutOfBounds(u128, u128),
     DivisionByZero,
+    AssertionFailed(RuntimeError),
 }
 
 impl fmt::Display for Error {
@@ -28,6 +29,7 @@ impl fmt::Display for Error {
             Error::DivisionByZero => {
                 write!(f, "Division by zero detected in zir during static analysis",)
             }
+            Error::AssertionFailed(err) => write!(f, "{}", err),
         }
     }
 }
@@ -53,6 +55,7 @@ impl<'ast, T: Field> ResultFolder<'ast, T> for ZirPropagator<'ast, T> {
         match s {
             ZirStatement::Assertion(e, error) => match self.fold_boolean_expression(e)? {
                 BooleanExpression::Value(true) => Ok(vec![]),
+                BooleanExpression::Value(false) => Err(Error::AssertionFailed(error)),
                 e => Ok(vec![ZirStatement::Assertion(e, error)]),
             },
             ZirStatement::Definition(a, e) => {

zokrates_core_test/tests/tests/assert_array_equality.json

@@ -0,0 +1,32 @@
+{
+    "entry_point": "./tests/tests/assert_array_equality.zok",
+    "curves": ["Bn128", "Bls12_381", "Bls12_377", "Bw6_761"],
+    "tests": [
+        {
+            "input": {
+                "values": ["1", "2"]
+            },
+            "output": {
+                "Ok": {
+                    "values": []
+                }
+            }
+        },
+        {
+            "input": {
+                "values": ["1", "1"]
+            },
+            "output": {
+                "Err": {
+                    "UnsatisfiedConstraint": {
+                        "left": "0",
+                        "right": "1",
+                        "error": {
+                            "SourceAssertion": "Assertion failed at ./tests/tests/assert_array_equality.zok:2:2"
+                        }
+                    }
+                }
+            }
+        }
+    ]
+}

zokrates_core_test/tests/tests/assert_array_equality.zok

@@ -0,0 +1,3 @@
+def main(field[2] a):
+	assert(a == [1, 2])
+	return