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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151

use jql_parser::errors::JqlParserError;
use serde_json::Value;
use thiserror::Error;

static SLICE_SEP: &str = " ... ";
static SLICE_LEN: usize = 7;
static SEP: &str = ", ";

/// Joins multiple `String`.
fn join(values: &[String]) -> String {
    values.join(SEP)
}

/// Shortens a JSON `Value` for error injection.
fn shorten(json: &Value) -> String {
    let full_json_string = json.to_string();

    if full_json_string.len() < SLICE_LEN * 2 + SLICE_SEP.len() {
        return full_json_string;
    }

    let start_slice = &full_json_string[..SLICE_LEN];
    let end_slice = &full_json_string[full_json_string.len() - SLICE_LEN..];

    [start_slice, end_slice].join(SLICE_SEP)
}

/// Returns the type of a JSON `Value`.
fn get_json_type(json: &Value) -> &str {
    match json {
        Value::Array(_) => "array",
        Value::Bool(_) => "boolean",
        Value::Null => "null",
        Value::Number(_) => "number",
        Value::Object(_) => "object",
        Value::String(_) => "string",
    }
}

/// Error type returned by the runner.
#[derive(Debug, Error, PartialEq)]
pub enum JqlRunnerError {
    /// Empty query error.
    #[error("Query is empty")]
    EmptyQueryError,

    /// Flatten error.
    #[error("Value {0} is neither an array nor an object and can't be flattened")]
    FlattenError(Value),

    /// Index out of bounds error.
    #[error("Index {index} in parent {parent} is out of bounds")]
    IndexOutOfBoundsError {
        /// Index.
        index: usize,
        /// Parent value.
        parent: Value,
    },

    /// Invalid array error.
    #[error("Value {0} is not a JSON array ({})", get_json_type(.0))]
    InvalidArrayError(Value),

    /// Invalid object error.
    #[error("Value {0} is not a JSON object ({})", get_json_type(.0))]
    InvalidObjectError(Value),

    /// Key not found error.
    #[error(r#"Key "{key}" doesn't exist in parent {}"#, shorten(parent))]
    KeyNotFoundError {
        /// Key not found.
        key: String,
        /// Parent value.
        parent: Value,
    },

    /// Keys not found error.
    #[error("Keys {} don't exist in parent {}", join(keys), shorten(parent))]
    MultiKeyNotFoundError {
        /// Keys not found.
        keys: Vec<String>,
        /// Parent value.
        parent: Value,
    },

    /// Parsing error.
    #[error(transparent)]
    ParsingError(#[from] JqlParserError),

    /// Pipe in error.
    #[error("Pipe in operator used on {0} which is not an array")]
    PipeInError(Value),

    /// Pipe in error.
    #[error("Pipe out operator used without a preceding pipe in operator")]
    PipeOutError,

    /// Range out of bounds error.
    #[error("Range [{start}:{end}] in parent {parent} is out of bounds")]
    RangeOutOfBoundsError {
        /// Start range.
        start: usize,
        /// End range.
        end: usize,
        /// parent value.
        parent: Value,
    },

    /// Unknown error.
    #[error("Unknown error")]
    UnknownError,
}

#[cfg(test)]
mod tests {

    use serde_json::json;

    use super::{
        get_json_type,
        join,
        shorten,
    };

    #[test]
    fn check_get_json_type() {
        assert_eq!(get_json_type(&json!([])), "array");
        assert_eq!(get_json_type(&json!(true)), "boolean");
        assert_eq!(get_json_type(&json!(null)), "null");
        assert_eq!(get_json_type(&json!(1)), "number");
        assert_eq!(get_json_type(&json!({})), "object");
        assert_eq!(get_json_type(&json!("a")), "string");
    }

    #[test]
    fn check_join() {
        assert_eq!(
            join(&["a".to_string(), "b".to_string(), "c".to_string()]),
            "a, b, c".to_string()
        );
    }

    #[test]
    fn check_shorten() {
        assert_eq!(shorten(&json!("thismakesnosense")), r#""thismakesnosense""#);
        assert_eq!(
            shorten(&json!({ "a": { "b": { "c": [1, 2 ,3, 4, 5, 6, 7, 8, 9] } } })),
            r#"{"a":{" ... 8,9]}}}"#.to_string()
        );
    }
}