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// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
use serde_json::{Map, Value};
use std::collections::HashMap;
#[cfg(feature = "stateful")]
pub type JsonObject = Map<String, Value>;
/// Replace any instance of [from] with [to] in any string within the [serde_json::Value].
///
/// This recursively descends into the object, looking at string values and keys.
#[allow(dead_code)]
pub(crate) fn replace_str(value: &mut Value, from: &str, to: &str) {
let replacer = create_str_replacer(from, to);
replace_str_with(value, &replacer);
}
/// Replace any instance of [from] with [to] in any string within the [serde_json::Value::Map].
///
/// This recursively descends into the object, looking at string values and keys.
pub(crate) fn replace_str_in_map(map: &mut Map<String, Value>, from: &str, to: &str) {
let replacer = create_str_replacer(from, to);
replace_str_in_map_with(map, &replacer);
}
fn replace_str_with<F>(value: &mut Value, replacer: &F)
where
F: Fn(&str) -> Option<String> + ?Sized,
{
match value {
Value::String(s) => {
if let Some(r) = replacer(s) {
*s = r;
}
}
Value::Array(list) => {
for item in list.iter_mut() {
replace_str_with(item, replacer);
}
}
Value::Object(map) => {
replace_str_in_map_with(map, replacer);
}
_ => (),
};
}
pub(crate) fn replace_str_in_map_with<F>(map: &mut Map<String, Value>, replacer: &F)
where
F: Fn(&str) -> Option<String> + ?Sized,
{
// Replace values in place.
for v in map.values_mut() {
replace_str_with(v, replacer);
}
// Replacing keys in place is a little trickier.
let mut changes = HashMap::new();
for k in map.keys() {
if let Some(new) = replacer(k) {
changes.insert(k.to_owned(), new);
}
}
for (k, new) in changes {
let v = map.remove(&k).unwrap();
_ = map.insert(new, v);
}
}
fn create_str_replacer<'a>(from: &'a str, to: &'a str) -> impl Fn(&str) -> Option<String> + 'a {
move |s: &str| -> Option<String> {
if s.contains(from) {
Some(s.replace(from, to))
} else {
None
}
}
}
#[cfg(test)]
mod unit_tests {
use super::*;
use serde_json::json;
#[test]
fn test_replace_str() {
let mut value = json!("{test}");
replace_str(&mut value, "{test}", "success");
assert_eq!(value, json!("success"));
let mut value = json!("{test}-postfix");
replace_str(&mut value, "{test}", "success");
assert_eq!(value, json!("success-postfix"));
let mut value = json!("prefix-{test}");
replace_str(&mut value, "{test}", "success");
assert_eq!(value, json!("prefix-success"));
let mut value = json!("prefix-{test}-postfix");
replace_str(&mut value, "{test}", "success");
assert_eq!(value, json!("prefix-success-postfix"));
let mut value = json!("prefix-{test}-multi-{test}-postfix");
replace_str(&mut value, "{test}", "success");
assert_eq!(value, json!("prefix-success-multi-success-postfix"));
}
#[test]
fn test_replace_str_in_array() {
let mut value = json!(["alice", "bob", "{placeholder}", "daphne"]);
replace_str(&mut value, "{placeholder}", "charlie");
assert_eq!(value, json!(["alice", "bob", "charlie", "daphne"]));
}
#[test]
fn test_replace_str_in_map() {
let mut value = json!({
"key": "{test}",
"not": true,
"or": 2,
});
replace_str(&mut value, "{test}", "success");
assert_eq!(
value,
json!({
"key": "success",
"not": true,
"or": 2,
})
);
}
#[test]
fn test_replace_str_in_map_keys() {
let mut value = json!({
"{test}-en-US": "{test}",
"not": true,
"or": 2,
});
replace_str(&mut value, "{test}", "success");
assert_eq!(
value,
json!({
"success-en-US": "success",
"not": true,
"or": 2,
})
);
}
#[test]
fn test_replace_str_mixed() {
let mut value = json!({
"messages": {
"{test}-en-US": {
"test": "{test}"
},
"{test}{test}": {
"test": "{test}{test}"
}
}
});
replace_str(&mut value, "{test}", "success");
assert_eq!(
value,
json!({
"messages": {
"success-en-US": {
"test": "success"
},
"successsuccess": {
"test": "successsuccess"
}
}
})
);
}
}