mirror of
https://github.com/serde-rs/json.git
synced 2025-10-02 07:21:29 +00:00
309ef6b887
This method inserts a key-value pair in the map at the given index. If the map did not have this key present, `None` is returned. If the map did have this key present, the key is moved to the new position, the value is updated, and the old value is returned. This is useful when you want to insert a key-value pair at a specific position in the map, and is a necessary method when writing a JSON editor that can mutate the keys in a JSON object.
58 lines
1.6 KiB
Rust
58 lines
1.6 KiB
Rust
use serde_json::{from_str, Map, Value};
|
|
|
|
#[test]
|
|
fn test_preserve_order() {
|
|
// Sorted order
|
|
#[cfg(not(feature = "preserve_order"))]
|
|
const EXPECTED: &[&str] = &["a", "b", "c"];
|
|
|
|
// Insertion order
|
|
#[cfg(feature = "preserve_order")]
|
|
const EXPECTED: &[&str] = &["b", "a", "c"];
|
|
|
|
let v: Value = from_str(r#"{"b":null,"a":null,"c":null}"#).unwrap();
|
|
let keys: Vec<_> = v.as_object().unwrap().keys().collect();
|
|
assert_eq!(keys, EXPECTED);
|
|
}
|
|
|
|
#[test]
|
|
#[cfg(feature = "preserve_order")]
|
|
fn test_shift_insert() {
|
|
let mut v: Value = from_str(r#"{"b":null,"a":null,"c":null}"#).unwrap();
|
|
let val = v.as_object_mut().unwrap();
|
|
val.shift_insert(0, "d".to_string(), Value::Null);
|
|
|
|
let keys: Vec<_> = val.keys().collect();
|
|
assert_eq!(keys, &["d", "b", "a", "c"]);
|
|
}
|
|
|
|
#[test]
|
|
fn test_append() {
|
|
// Sorted order
|
|
#[cfg(not(feature = "preserve_order"))]
|
|
const EXPECTED: &[&str] = &["a", "b", "c"];
|
|
|
|
// Insertion order
|
|
#[cfg(feature = "preserve_order")]
|
|
const EXPECTED: &[&str] = &["b", "a", "c"];
|
|
|
|
let mut v: Value = from_str(r#"{"b":null,"a":null,"c":null}"#).unwrap();
|
|
let val = v.as_object_mut().unwrap();
|
|
let mut m = Map::new();
|
|
m.append(val);
|
|
let keys: Vec<_> = m.keys().collect();
|
|
|
|
assert_eq!(keys, EXPECTED);
|
|
assert!(val.is_empty());
|
|
}
|
|
|
|
#[test]
|
|
fn test_retain() {
|
|
let mut v: Value = from_str(r#"{"b":null,"a":null,"c":null}"#).unwrap();
|
|
let val = v.as_object_mut().unwrap();
|
|
val.retain(|k, _| k.as_str() != "b");
|
|
|
|
let keys: Vec<_> = val.keys().collect();
|
|
assert_eq!(keys, &["a", "c"]);
|
|
}
|