1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131

//! Declare error types.

/// An error related to an option passed to Arti via a configuration
/// builder.
#[derive(Debug, Clone, thiserror::Error)]
#[non_exhaustive]
pub enum ConfigBuildError {
    /// A mandatory field was not present.
    #[error("Field was not provided: {field}")]
    MissingField {
        /// The name of the missing field.
        field: String,
    },
    /// A single field had a value that proved to be unusable.
    #[error("Value of {field} was incorrect: {problem}")]
    Invalid {
        /// The name of the invalid field
        field: String,
        /// A description of the problem.
        problem: String,
    },
    /// Multiple fields are inconsistent.
    #[error("Fields {fields:?} are inconsistent: {problem}")]
    Inconsistent {
        /// The names of the inconsistent fields
        fields: Vec<String>,
        /// The problem that makes them inconsistent
        problem: String,
    },
}

impl From<derive_builder::UninitializedFieldError> for ConfigBuildError {
    fn from(val: derive_builder::UninitializedFieldError) -> Self {
        ConfigBuildError::MissingField {
            field: val.field_name().to_string(),
        }
    }
}

impl ConfigBuildError {
    /// Return a new ConfigBuildError that prefixes its field name with
    /// `prefix` and a dot.
    #[must_use]
    pub fn within(&self, prefix: &str) -> Self {
        use ConfigBuildError::*;
        match self {
            MissingField { field } => MissingField {
                field: format!("{}.{}", prefix, field),
            },
            Invalid { field, problem } => Invalid {
                field: format!("{}.{}", prefix, field),
                problem: problem.clone(),
            },
            Inconsistent { fields, problem } => Inconsistent {
                fields: fields.iter().map(|f| format!("{}.{}", prefix, f)).collect(),
                problem: problem.clone(),
            },
        }
    }
}

/// An error caused when attempting to reconfigure an existing Arti client, or one of its modules.
#[derive(Debug, Clone, thiserror::Error)]
#[non_exhaustive]
pub enum ReconfigureError {
    /// Tried to change a field that cannot change on a running client.
    #[error("Cannot change {field} on a running client.")]
    CannotChange {
        /// The field (or fields) that we tried to change.
        field: String,
    },
}

#[cfg(test)]
mod test {
    #![allow(clippy::unwrap_used)]
    use super::*;

    #[test]
    fn within() {
        let e1 = ConfigBuildError::MissingField {
            field: "lettuce".to_owned(),
        };
        let e2 = ConfigBuildError::Invalid {
            field: "tomato".to_owned(),
            problem: "too crunchy".to_owned(),
        };
        let e3 = ConfigBuildError::Inconsistent {
            fields: vec!["mayo".to_owned(), "avocado".to_owned()],
            problem: "pick one".to_owned(),
        };

        assert_eq!(
            &e1.within("sandwich").to_string(),
            "Field was not provided: sandwich.lettuce"
        );
        assert_eq!(
            &e2.within("sandwich").to_string(),
            "Value of sandwich.tomato was incorrect: too crunchy"
        );
        assert_eq!(
            &e3.within("sandwich").to_string(),
            r#"Fields ["sandwich.mayo", "sandwich.avocado"] are inconsistent: pick one"#
        );
    }

    #[derive(derive_builder::Builder, Debug)]
    #[builder(build_fn(error = "ConfigBuildError"))]
    #[allow(dead_code)]
    struct Cephalopod {
        // arms have suction cups for their whole length
        arms: u8,
        // Tentacles have suction cups at the ends
        tentacles: u8,
    }

    #[test]
    fn build_err() {
        let squid = CephalopodBuilder::default().arms(8).tentacles(2).build();
        let octopus = CephalopodBuilder::default().arms(8).build();
        assert!(squid.is_ok());
        let squid = squid.unwrap();
        assert_eq!(squid.arms, 8);
        assert_eq!(squid.tentacles, 2);
        assert!(octopus.is_err());
        assert_eq!(
            &octopus.unwrap_err().to_string(),
            "Field was not provided: tentacles"
        );
    }
}