feat(execution-engine)!: this patch prohibits error code = 0 (#702)

air/src/execution_step/errors/catchable_errors.rs

@@ -17,7 +17,7 @@
 use super::ErrorAffectable;
 use super::Joinable;
 use crate::execution_step::execution_context::errors::StreamMapError;
-use crate::execution_step::execution_context::LastErrorObjectError;
+use crate::execution_step::execution_context::ErrorObjectError;
 use crate::execution_step::lambda_applier::LambdaError;
 use crate::JValue;
 use crate::ToErrorCode;
@@ -77,7 +77,7 @@ pub enum CatchableError {
 
     /// This error type is produced by a fail instruction that tries to throw a scalar that have inappropriate type.
     #[error(transparent)]
-    InvalidLastErrorObjectError(#[from] LastErrorObjectError),
+    InvalidErrorObjectError(#[from] ErrorObjectError),
 
     /// A new with this variable name was met and right after that it was accessed
     /// that is prohibited.

air/src/execution_step/execution_context/instruction_error/errors.rs

@@ -20,7 +20,7 @@ use thiserror::Error as ThisError;
 
 /// Describes errors related to converting a scalar into error object.
 #[derive(Debug, Clone, ThisError)]
-pub enum LastErrorObjectError {
+pub enum ErrorObjectError {
     #[error("scalar should have an object type to be converted into error object, but '{0}' doesn't have")]
     ScalarMustBeObject(JValue),
 
@@ -33,4 +33,7 @@ pub enum LastErrorObjectError {
         field_name: &'static str,
         expected_type: &'static str,
     },
+
+    #[error("error code must be non-zero, but it is zero")]
+    ErrorCodeMustBeNonZero,
 }

air/src/execution_step/execution_context/instruction_error/instruction_error_definition.rs

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-use super::LastErrorObjectError;
+use super::ErrorObjectError;
 use crate::execution_step::RcSecurityTetraplet;
 use crate::JValue;
 
@@ -72,25 +72,25 @@ pub(crate) fn error_from_raw_fields(error_code: i64, error_message: &str, instru
 }
 
 /// Checks that a scalar is a value of an object types that contains at least two fields:
-///  - error_code
+///  - error_code != 0
 ///  - message
-pub(crate) fn check_error_object(scalar: &JValue) -> Result<(), LastErrorObjectError> {
+pub(crate) fn check_error_object(scalar: &JValue) -> Result<(), ErrorObjectError> {
     let fields = match scalar {
         JValue::Object(fields) => fields,
-        _ => return Err(LastErrorObjectError::ScalarMustBeObject(scalar.clone())),
+        _ => return Err(ErrorObjectError::ScalarMustBeObject(scalar.clone())),
     };
 
     let check_field = |field_name| {
         fields
             .get(field_name)
-            .ok_or_else(|| LastErrorObjectError::ScalarMustContainField {
+            .ok_or_else(|| ErrorObjectError::ScalarMustContainField {
                 scalar: scalar.clone(),
                 field_name,
             })
     };
 
     let error_code = check_field(ERROR_CODE_FIELD_NAME)?;
-    ensure_jvalue_is_integer(scalar, error_code, ERROR_CODE_FIELD_NAME)?;
+    ensure_error_code_correct(scalar, error_code, ERROR_CODE_FIELD_NAME)?;
 
     let message = check_field(MESSAGE_FIELD_NAME)?;
     ensure_jvalue_is_string(scalar, message, MESSAGE_FIELD_NAME)?;
@@ -98,14 +98,16 @@ pub(crate) fn check_error_object(scalar: &JValue) -> Result<(), LastErrorObjectE
     Ok(())
 }
 
-fn ensure_jvalue_is_integer(
+fn ensure_error_code_correct(
     scalar: &JValue,
     value: &JValue,
     field_name: &'static str,
-) -> Result<(), LastErrorObjectError> {
+) -> Result<(), ErrorObjectError> {
     match value {
-        JValue::Number(number) if number.is_i64() || number.is_u64() => Ok(()),
-        _ => Err(LastErrorObjectError::ScalarFieldIsWrongType {
+        JValue::Number(number) if number.is_i64() | number.is_u64() => {
+            ensure_error_code_is_error(number.as_i64().unwrap())
+        }
+        _ => Err(ErrorObjectError::ScalarFieldIsWrongType {
             scalar: scalar.clone(),
             field_name,
             expected_type: "integer",
@@ -113,14 +115,18 @@ fn ensure_jvalue_is_integer(
     }
 }
 
-fn ensure_jvalue_is_string(
-    scalar: &JValue,
-    value: &JValue,
-    field_name: &'static str,
-) -> Result<(), LastErrorObjectError> {
+fn ensure_error_code_is_error(number: i64) -> Result<(), ErrorObjectError> {
+    if number == NO_ERROR_ERROR_CODE {
+        Err(ErrorObjectError::ErrorCodeMustBeNonZero)
+    } else {
+        Ok(())
+    }
+}
+
+fn ensure_jvalue_is_string(scalar: &JValue, value: &JValue, field_name: &'static str) -> Result<(), ErrorObjectError> {
     match value {
         JValue::String(_) => Ok(()),
-        _ => Err(LastErrorObjectError::ScalarFieldIsWrongType {
+        _ => Err(ErrorObjectError::ScalarFieldIsWrongType {
             scalar: scalar.clone(),
             field_name,
             expected_type: "string",

air/src/execution_step/execution_context/instruction_error/mod.rs

@@ -20,7 +20,7 @@ mod errors_utils;
 mod instruction_error_definition;
 mod last_error_descriptor;
 
-pub use errors::LastErrorObjectError;
+pub use errors::ErrorObjectError;
 pub use instruction_error_definition::no_error;
 pub use instruction_error_definition::no_error_object;
 pub use instruction_error_definition::InstructionError;

air/src/execution_step/instructions/fail.rs

@@ -55,7 +55,7 @@ fn fail_with_scalar<'i>(scalar: &ast::Scalar<'i>, exec_ctx: &mut ExecutionCtx<'i
     let (value, mut tetraplet, provenance) = scalar.resolve(exec_ctx)?;
     // tetraplets always have one element here and it'll be refactored after boxed value
     let tetraplet = tetraplet.remove(0);
-    check_error_object(&value).map_err(CatchableError::InvalidLastErrorObjectError)?;
+    check_error_object(&value).map_err(CatchableError::InvalidErrorObjectError)?;
 
     fail_with_error_object(exec_ctx, Rc::new(value), Some(tetraplet), provenance)
 }
@@ -64,7 +64,7 @@ fn fail_with_scalar_wl<'i>(scalar: &ast::ScalarWithLambda<'i>, exec_ctx: &mut Ex
     let (value, mut tetraplet, provenance) = scalar.resolve(exec_ctx)?;
     // tetraplets always have one element here and it'll be refactored after boxed value
     let tetraplet = tetraplet.remove(0);
-    check_error_object(&value).map_err(CatchableError::InvalidLastErrorObjectError)?;
+    check_error_object(&value).map_err(CatchableError::InvalidErrorObjectError)?;
 
     fail_with_error_object(exec_ctx, Rc::new(value), Some(tetraplet), provenance)
 }
@@ -97,7 +97,7 @@ fn fail_with_canon_stream(
     let (value, mut tetraplets, provenance) = ast_canon.resolve(exec_ctx)?;
 
     // tetraplets always have one element here and it'll be refactored after boxed value
-    check_error_object(&value).map_err(CatchableError::InvalidLastErrorObjectError)?;
+    check_error_object(&value).map_err(CatchableError::InvalidErrorObjectError)?;
 
     fail_with_error_object(exec_ctx, Rc::new(value), Some(tetraplets.remove(0)), provenance)
 }
@@ -111,6 +111,8 @@ fn fail_with_last_error(exec_ctx: &mut ExecutionCtx<'_>) -> ExecutionResult<()>
         provenance,
     } = exec_ctx.last_error_descriptor.error();
 
+    check_error_object(error).map_err(CatchableError::InvalidErrorObjectError)?;
+
     // to avoid warnings from https://github.com/rust-lang/rust/issues/59159
     let error = error.clone();
     let tetraplet = tetraplet.clone();
@@ -127,6 +129,8 @@ fn fail_with_error(exec_ctx: &mut ExecutionCtx<'_>) -> ExecutionResult<()> {
         provenance,
     } = exec_ctx.error_descriptor.error();
 
+    check_error_object(error).map_err(CatchableError::InvalidErrorObjectError)?;
+
     fail_with_error_object(exec_ctx, error.clone(), tetraplet.clone(), provenance.clone())
 }
 

air/src/execution_step/mod.rs

@@ -29,7 +29,7 @@ const TETRAPLET_IDX_CORRECT: &str = "selects always return a correct index insid
 pub use errors::CatchableError;
 pub use errors::ExecutionError;
 pub use errors::UncatchableError;
-pub use execution_context::LastErrorObjectError;
+pub use execution_context::ErrorObjectError;
 pub use lambda_applier::LambdaError;
 
 pub mod errors_prelude {

air/src/lib.rs

@@ -46,9 +46,9 @@ pub use execution_step::execution_context::InstructionError;
 pub use execution_step::execution_context::NO_ERROR_ERROR_CODE;
 pub use execution_step::execution_context::NO_ERROR_MESSAGE;
 pub use execution_step::CatchableError;
+pub use execution_step::ErrorObjectError;
 pub use execution_step::ExecutionError;
 pub use execution_step::LambdaError;
-pub use execution_step::LastErrorObjectError;
 pub use execution_step::UncatchableError;
 pub use farewell_step::FarewellError;
 pub use polyplets::ResolvedTriplet;

air/tests/test_module/features/errors/error.rs

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2023 Fluence Labs Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+use air::no_error_object;
+use air::ExecutionCidState;
+use air_test_framework::AirScriptExecutor;
+use air_test_utils::prelude::*;
+
+#[test]
+fn fail_with_rebubble_error() {
+    let peer_id = "peer_id";
+    let script = r#"
+    (seq
+        (xor
+            (xor
+                (match 1 2 (null) )
+                (fail :error:)
+            )
+            (call "peer_id" ("m" "f1") [:error:] scalar1) ; behaviour = echo
+        )
+        (call "peer_id" ("m" "f2") [:error:] scalar2) ; behaviour = echo
+    )
+    "#
+    .to_string();
+
+    let executor = AirScriptExecutor::from_annotated(TestRunParameters::from_init_peer_id(peer_id), &script)
+        .expect("invalid test AIR script");
+    let result = executor.execute_all(peer_id).unwrap();
+    let actual_trace = trace_from_result(&result.last().unwrap());
+
+    let mut cid_tracker: ExecutionCidState = ExecutionCidState::new();
+    let expected_error_json = {
+        json!({
+          "error_code": 10006,
+          "instruction": "xor",
+          "message": "fail with '{\"error_code\":10001,\"instruction\":\"match 1 2\",\"message\":\"compared values do not match\"}' is used without corresponding xor"
+        })
+    };
+
+    let expected_trace: Vec<ExecutedState> = vec![
+        scalar_tracked!(
+            expected_error_json.clone(),
+            cid_tracker,
+            peer = peer_id,
+            service = "m..0",
+            function = "f1",
+            args = [expected_error_json]
+        ),
+        scalar_tracked!(
+            no_error_object(),
+            cid_tracker,
+            peer = peer_id,
+            service = "m..1",
+            function = "f2",
+            args = [no_error_object()]
+        ),
+    ];
+
+    assert_eq!(actual_trace, expected_trace,);
+}

air/tests/test_module/features/errors/last_error.rs

@@ -16,10 +16,10 @@
 
 use air::no_error_object;
 use air::CatchableError;
+use air::ErrorObjectError;
 use air::ExecutionCidState;
 use air::ExecutionError;
 use air::LambdaError;
-use air::LastErrorObjectError;
 use air::SecurityTetraplet;
 use air::NO_ERROR_ERROR_CODE;
 use air::NO_ERROR_MESSAGE;
@@ -422,7 +422,7 @@ fn fail_with_scalar_from_call_not_enough_fields() {
 
     let result = call_vm!(vm, <_>::default(), &script, "", "");
 
-    let expected_error = CatchableError::InvalidLastErrorObjectError(LastErrorObjectError::ScalarMustContainField {
+    let expected_error = CatchableError::InvalidErrorObjectError(ErrorObjectError::ScalarMustContainField {
         scalar: service_result,
         field_name: "message",
     });
@@ -446,8 +446,7 @@ fn fail_with_scalar_from_call_not_right_type() {
 
     let result = call_vm!(vm, <_>::default(), &script, "", "");
 
-    let expected_error =
-        CatchableError::InvalidLastErrorObjectError(LastErrorObjectError::ScalarMustBeObject(service_result));
+    let expected_error = CatchableError::InvalidErrorObjectError(ErrorObjectError::ScalarMustBeObject(service_result));
     assert!(check_error(&result, expected_error));
 }
 
@@ -468,7 +467,7 @@ fn fail_with_scalar_from_call_field_not_right_type() {
 
     let result = call_vm!(vm, <_>::default(), &script, "", "");
 
-    let expected_error = CatchableError::InvalidLastErrorObjectError(LastErrorObjectError::ScalarFieldIsWrongType {
+    let expected_error = CatchableError::InvalidErrorObjectError(ErrorObjectError::ScalarFieldIsWrongType {
         scalar: service_result,
         field_name: "error_code",
         expected_type: "integer",

air/tests/test_module/features/errors/mod.rs

@@ -14,5 +14,6 @@
  * limitations under the License.
  */
 
+mod error;
 mod invalid_air;
 mod last_error;

air/tests/test_module/instructions/fail.rs

@@ -15,6 +15,9 @@
  */
 
 use air::CatchableError;
+use air::ErrorObjectError;
+use air::ExecutionError;
+use air_test_framework::AirScriptExecutor;
 use air_test_utils::prelude::*;
 
 #[test]
@@ -209,3 +212,58 @@ fn fail_with_canon_stream() {
     };
     assert!(check_error(&result, expected_error));
 }
+
+fn fail_to_fail_with_unsupported_errorcode(script: &str) {
+    let local_peer_id = "local_peer_id";
+    let script = script.to_string();
+
+    let executor = AirScriptExecutor::from_annotated(TestRunParameters::from_init_peer_id(local_peer_id), &script)
+        .expect("invalid test AIR script");
+    let results = executor.execute_all(local_peer_id).unwrap();
+
+    let expected_error = ExecutionError::Catchable(rc!(CatchableError::InvalidErrorObjectError(
+        ErrorObjectError::ErrorCodeMustBeNonZero
+    )));
+    assert!(check_error(&results.last().unwrap(), expected_error));
+}
+
+#[test]
+fn fail_to_fail_with_unsupported_errorcode_in_scalar() {
+    let script = r#"
+        (seq
+            (call "local_peer_id" ("m" "f1") [] scalar) ; ok = {"error_code": 0, "message": "some message"}
+            (fail scalar)
+        )
+    "#;
+    fail_to_fail_with_unsupported_errorcode(script);
+}
+
+#[test]
+fn fail_to_fail_with_unsupported_errorcode_in_scalar_wl() {
+    let script = r#"
+        (seq
+            (call "local_peer_id" ("m" "f1") [] scalar) ; ok = {"key": {"error_code": 0, "message": "some message"} }
+            (fail scalar.$.key)
+        )
+    "#;
+    fail_to_fail_with_unsupported_errorcode(script);
+}
+
+#[test]
+fn fail_to_fail_with_unsupported_errorcode_in_canon() {
+    let script = r#"
+        (seq
+            (call "local_peer_id" ("m" "f1") [] scalar) ; ok = [{"error_code": 0, "message": "some message"}]
+            (fail scalar.$.[0])
+        )
+    "#;
+    fail_to_fail_with_unsupported_errorcode(script);
+}
+
+#[test]
+fn fail_to_fail_with_unsupported_errorcode_in_error() {
+    let script = r#"
+        (fail :error:)
+    "#;
+    fail_to_fail_with_unsupported_errorcode(script);
+}

crates/air-lib/air-parser/src/parser/air.lalrpop

@@ -86,7 +86,10 @@ Instr: Box<Instruction<'input>> = {
         Box::new(Instruction::New(new))
     },
 
-    "(" fail <fail_body: FailBody> ")" => {
+    <left: @L> "(" fail <fail_body: FailBody> ")" <right: @R> => {
+        let span = Span::new(left, right);
+        validator.met_fail_literal(&fail_body, span);
+
         Box::new(Instruction::Fail(fail_body))
     },
 

crates/air-lib/air-parser/src/parser/errors.rs

@@ -53,6 +53,9 @@ pub enum ParserError {
         ap_key_type: String,
         ap_result_name: String,
     },
+
+    #[error("error code 0 with fail is unsupported")]
+    UnsupportedLiteralErrCodes { span: Span },
 }
 
 impl ParserError {
@@ -67,6 +70,7 @@ impl ParserError {
             Self::MultipleIterableValuesForOneIterator { span, .. } => *span,
             Self::MultipleNextInFold { span, .. } => *span,
             Self::UnsupportedMapKeyType { span, .. } => *span,
+            Self::UnsupportedLiteralErrCodes { span } => *span,
         }
     }
 
@@ -116,6 +120,10 @@ impl ParserError {
             ap_result_name: ap_result_name.into(),
         }
     }
+
+    pub fn unsupported_literal_errcodes(span: Span) -> Self {
+        Self::UnsupportedLiteralErrCodes { span }
+    }
 }
 
 impl From<std::convert::Infallible> for ParserError {

crates/air-lib/air-parser/src/parser/tests/dsl.rs

@@ -92,6 +92,10 @@ pub(super) fn fail_last_error() -> Instruction<'static> {
     Instruction::Fail(Fail::LastError)
 }
 
+pub(super) fn fail_error() -> Instruction<'static> {
+    Instruction::Fail(Fail::Error)
+}
+
 pub(super) fn fold_scalar_variable<'i>(
     scalar: Scalar<'i>,
     iterator: Scalar<'i>,

crates/air-lib/air-parser/src/parser/tests/fail.rs

@@ -68,3 +68,47 @@ fn parse_fail_scalar_with_lambda() {
     ));
     assert_eq!(instruction, expected)
 }
+
+#[test]
+fn parse_fail_scalar_with_error() {
+    let source_code = r#"
+           (fail :error:)
+        "#;
+    let instruction = parse(source_code);
+    let expected = fail_error();
+    assert_eq!(instruction, expected)
+}
+
+#[test]
+fn parse_fail_literal_0() {
+    use crate::parser::errors::ParserError;
+    use lalrpop_util::ParseError;
+
+    let source_code = r#"
+           (fail 0 "some error")
+        "#;
+
+    let lexer = crate::AIRLexer::new(source_code);
+
+    let parser = crate::AIRParser::new();
+    let mut errors = Vec::new();
+    let mut validator = crate::parser::VariableValidator::new();
+    parser
+        .parse(source_code, &mut errors, &mut validator, lexer)
+        .expect("parser shouldn't fail");
+
+    let errors = validator.finalize();
+
+    assert_eq!(errors.len(), 1);
+
+    let error = &errors[0].error;
+    let parser_error = match error {
+        ParseError::User { error } => error,
+        _ => panic!("unexpected error type"),
+    };
+
+    assert!(matches!(
+        parser_error,
+        ParserError::UnsupportedLiteralErrCodes { .. }
+    ));
+}

crates/air-lib/air-parser/src/parser/validator.rs

@@ -59,9 +59,12 @@ pub struct VariableValidator<'i> {
     /// Contains all names that should be checked that they are not iterators.
     not_iterators_candidates: Vec<(&'i str, Span)>,
 
-    // This contains info about unssuported map key arguments used with ap instruction,
-    // namely (key map ApArgument)
+    /// This contains info about unssuported map key arguments used with ap instruction,
+    /// namely (key map ApArgument).
     unsupported_map_keys: Vec<(String, &'i str, Span)>,
+
+    /// This vector contains all literal error codes used with fail.
+    unsupported_literal_errcodes: Vec<(i64, Span)>,
 }
 
 impl<'i> VariableValidator<'i> {
@@ -197,6 +200,15 @@ impl<'i> VariableValidator<'i> {
         }
     }
 
+    pub(super) fn met_fail_literal(&mut self, fail: &Fail<'i>, span: Span) {
+        match fail {
+            Fail::Literal { ret_code, .. } if *ret_code == 0 => {
+                self.unsupported_literal_errcodes.push((*ret_code, span))
+            }
+            _ => {}
+        }
+    }
+
     pub(super) fn finalize(self) -> Vec<ErrorRecovery<AirPos, Token<'i>, ParserError>> {
         ValidatorErrorBuilder::new(self)
             .check_undefined_variables()
@@ -205,6 +217,7 @@ impl<'i> VariableValidator<'i> {
             .check_new_on_iterators()
             .check_iterator_for_multiple_definitions()
             .check_for_unsupported_map_keys()
+            .check_for_unsupported_literal_errcodes()
             .build()
     }
 
@@ -496,6 +509,14 @@ impl<'i> ValidatorErrorBuilder<'i> {
         self
     }
 
+    fn check_for_unsupported_literal_errcodes(mut self) -> Self {
+        for (_, span) in self.validator.unsupported_literal_errcodes.iter_mut() {
+            let error = ParserError::unsupported_literal_errcodes(*span);
+            add_to_errors(&mut self.errors, *span, Token::New, error);
+        }
+        self
+    }
+
     fn build(self) -> Vec<ErrorRecovery<AirPos, Token<'i>, ParserError>> {
         self.errors
     }