Files
jspg/src/validator/instance.rs

99 lines
2.3 KiB
Rust

use serde_json::Value;
use HashSet;
use std::ptr::NonNull;
pub trait ValidationInstance<'a>: Copy + Clone {
fn as_value(&self) -> &'a Value;
fn child_at_key(&self, key: &str) -> Option<Self>;
fn child_at_index(&self, idx: usize) -> Option<Self>;
fn prune_object(&self, _keys: &HashSet<String>) {}
fn prune_array(&self, _indices: &HashSet<usize>) {}
}
#[derive(Clone, Copy)]
pub struct ReadOnlyInstance<'a>(pub &'a Value);
impl<'a> ValidationInstance<'a> for ReadOnlyInstance<'a> {
fn as_value(&self) -> &'a Value {
self.0
}
fn child_at_key(&self, key: &str) -> Option<Self> {
self.0.get(key).map(ReadOnlyInstance)
}
fn child_at_index(&self, idx: usize) -> Option<Self> {
self.0.get(idx).map(ReadOnlyInstance)
}
}
#[derive(Clone, Copy)]
pub struct MutableInstance {
ptr: NonNull<Value>,
}
impl MutableInstance {
pub fn new(val: &mut Value) -> Self {
Self {
ptr: NonNull::from(val),
}
}
}
impl<'a> ValidationInstance<'a> for MutableInstance {
fn as_value(&self) -> &'a Value {
unsafe { self.ptr.as_ref() }
}
fn child_at_key(&self, key: &str) -> Option<Self> {
unsafe {
if let Some(obj) = self.ptr.as_ref().as_object() {
if obj.contains_key(key) {
let parent_mut = &mut *self.ptr.as_ptr();
if let Some(child_val) = parent_mut.get_mut(key) {
return Some(MutableInstance::new(child_val));
}
}
}
None
}
}
fn child_at_index(&self, idx: usize) -> Option<Self> {
unsafe {
if let Some(arr) = self.ptr.as_ref().as_array() {
if idx < arr.len() {
let parent_mut = &mut *self.ptr.as_ptr();
if let Some(child_val) = parent_mut.get_mut(idx) {
return Some(MutableInstance::new(child_val));
}
}
}
None
}
}
fn prune_object(&self, keys: &HashSet<String>) {
unsafe {
let val_mut = &mut *self.ptr.as_ptr();
if let Some(obj) = val_mut.as_object_mut() {
obj.retain(|k, _| keys.contains(k));
}
}
}
fn prune_array(&self, indices: &HashSet<usize>) {
unsafe {
let val_mut = &mut *self.ptr.as_ptr();
if let Some(arr) = val_mut.as_array_mut() {
let mut i = 0;
arr.retain(|_| {
let keep = indices.contains(&i);
i += 1;
keep
});
}
}
}
}