diff --git a/src/uu/expr/src/syntax_tree.rs b/src/uu/expr/src/syntax_tree.rs index ad421edb7..eaa6be1f5 100644 --- a/src/uu/expr/src/syntax_tree.rs +++ b/src/uu/expr/src/syntax_tree.rs @@ -161,7 +161,8 @@ impl AstNode { { let mut out = Vec::with_capacity(operands.len()); let mut operands = operands.iter(); - + // check the first value before `|`, stop evaluate and return directly if it is true. + // push dummy to pass the check of `len() == 2` if op_type == "|" { if let Some(value) = operands.next() { let value = value.evaluate()?;