diff --git a/dsc_lib/src/functions/mod.rs b/dsc_lib/src/functions/mod.rs index 28eddc4b..0accfa02 100644 --- a/dsc_lib/src/functions/mod.rs +++ b/dsc_lib/src/functions/mod.rs @@ -13,6 +13,7 @@ pub mod concat; pub mod create_array; pub mod div; pub mod envvar; +pub mod mod_function; pub mod mul; pub mod parameters; pub mod resource_id; @@ -64,6 +65,7 @@ impl FunctionDispatcher { functions.insert("createArray".to_string(), Box::new(create_array::CreateArray{})); functions.insert("div".to_string(), Box::new(div::Div{})); functions.insert("envvar".to_string(), Box::new(envvar::Envvar{})); + functions.insert("mod".to_string(), Box::new(mod_function::Mod{})); functions.insert("mul".to_string(), Box::new(mul::Mul{})); functions.insert("parameters".to_string(), Box::new(parameters::Parameters{})); functions.insert("resourceId".to_string(), Box::new(resource_id::ResourceId{})); diff --git a/dsc_lib/src/functions/mod_function.rs b/dsc_lib/src/functions/mod_function.rs new file mode 100644 index 00000000..50e63b4a --- /dev/null +++ b/dsc_lib/src/functions/mod_function.rs @@ -0,0 +1,79 @@ +// Copyright (c) Microsoft Corporation. +// Licensed under the MIT License. + +use crate::DscError; +use crate::configure::context::Context; +use crate::functions::{AcceptedArgKind, Function}; +use serde_json::Value; +use tracing::debug; + +#[derive(Debug, Default)] +pub struct Mod {} + +impl Function for Mod { + fn min_args(&self) -> usize { + 2 + } + + fn max_args(&self) -> usize { + 2 + } + + fn accepted_arg_types(&self) -> Vec { + vec![AcceptedArgKind::Number] + } + + fn invoke(&self, args: &[Value], _context: &Context) -> Result { + debug!("mod function"); + if let (Some(arg1), Some(arg2)) = (args[0].as_i64(), args[1].as_i64()) { + if arg2 == 0 { + return Err(DscError::Parser("Cannot divide by zero".to_string())); + } + Ok(Value::Number((arg1 % arg2).into())) + } else { + Err(DscError::Parser("Invalid argument(s)".to_string())) + } + } +} + +#[cfg(test)] +mod tests { + use crate::configure::context::Context; + use crate::parser::Statement; + + #[test] + fn numbers() { + let mut parser = Statement::new().unwrap(); + let result = parser.parse_and_execute("[mod(7, 3)]", &Context::new()).unwrap(); + assert_eq!(result, 1); + } + + #[test] + fn nested() { + let mut parser = Statement::new().unwrap(); + let result = parser.parse_and_execute("[mod(18, mod(8, 3))]", &Context::new()).unwrap(); + assert_eq!(result, 0); + } + + #[test] + fn invalid_one_parameter() { + let mut parser = Statement::new().unwrap(); + let result = parser.parse_and_execute("[mod(5)]", &Context::new()); + assert!(result.is_err()); + } + + #[test] + fn invalid_div_by_zero() { + let mut parser = Statement::new().unwrap(); + let result = parser.parse_and_execute("[mod(5, 0)]", &Context::new()); + assert!(result.is_err()); + } + + #[test] + fn overflow_input() { + let mut parser = Statement::new().unwrap(); + // max value for i64 is 2^63 -1 (or 9,223,372,036,854,775,807) + let result = parser.parse_and_execute("[mod(9223372036854775808, 2)]", &Context::new()); + assert!(result.is_err()); + } +}