-
Notifications
You must be signed in to change notification settings - Fork 180
/
patch_apply.rs
401 lines (342 loc) · 14.1 KB
/
patch_apply.rs
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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
//! Defines the algorithm for applying generated patches.
use std::{
collections::{HashMap, HashSet},
mem::take,
};
use rbx_dom_weak::types::{Ref, Variant};
use super::{
patch::{AppliedPatchSet, AppliedPatchUpdate, PatchSet, PatchUpdate},
InstanceSnapshot, RojoTree,
};
use crate::{multimap::MultiMap, RojoRef, REF_ID_ATTRIBUTE_NAME, REF_POINTER_ATTRIBUTE_PREFIX};
/// Consumes the input `PatchSet`, applying all of its prescribed changes to the
/// tree and returns an `AppliedPatchSet`, which can be used to keep another
/// tree in sync with Rojo's.
#[profiling::function]
pub fn apply_patch_set(tree: &mut RojoTree, patch_set: PatchSet) -> AppliedPatchSet {
let mut context = PatchApplyContext::default();
{
profiling::scope!("removals");
for removed_id in patch_set.removed_instances {
apply_remove_instance(&mut context, tree, removed_id);
}
}
{
profiling::scope!("additions");
for add_patch in patch_set.added_instances {
apply_add_child(&mut context, tree, add_patch.parent_id, add_patch.instance);
}
}
{
profiling::scope!("updates");
// Updates need to be applied after additions, which reduces the complexity
// of updates significantly.
for update_patch in patch_set.updated_instances {
apply_update_child(&mut context, tree, update_patch);
}
}
finalize_patch_application(context, tree)
}
/// All of the ephemeral state needing during application of a patch.
#[derive(Default)]
struct PatchApplyContext {
/// A map from transient snapshot IDs (generated by snapshot middleware) to
/// instance IDs in the actual tree. These are both the same data type so
/// that they fit into the same `Variant::Ref` type.
///
/// At this point in the patch process, IDs in instance properties have been
/// partially translated from 'snapshot space' into 'tree space' by the
/// patch computation process. An ID not existing in this map means either:
///
/// 1. The ID is already in tree space and refers to an instance that
/// existed in the tree before this patch was applied.
///
/// 2. The ID if in snapshot space, but points to an instance that was not
/// part of the snapshot that was put through the patch computation
/// function.
///
/// #2 should not occur in well-formed projects, but is indistinguishable
/// from #1 right now. It could happen if two model files try to reference
/// eachother.
snapshot_id_to_instance_id: HashMap<Ref, Ref>,
/// Tracks all of the instances added by this patch that have refs that need
/// to be rewritten.
has_refs_to_rewrite: HashSet<Ref>,
/// Tracks all ref properties that were specified using attributes. This has
/// to be handled after everything else is done just like normal referent
/// properties.
attribute_refs_to_rewrite: MultiMap<Ref, (String, String)>,
/// The current applied patch result, describing changes made to the tree.
applied_patch_set: AppliedPatchSet,
}
/// Finalize this patch application, consuming the context, applying any
/// deferred property updates, and returning the finally applied patch set.
///
/// Ref properties from snapshots refer to eachother via snapshot ID. Some of
/// these properties are transformed when the patch is computed, notably the
/// instances that the patch computing method is able to pair up.
///
/// The remaining Ref properties need to be handled during patch application,
/// where we build up a map of snapshot IDs to instance IDs as they're created,
/// then apply properties all at once at the end.
#[profiling::function]
fn finalize_patch_application(context: PatchApplyContext, tree: &mut RojoTree) -> AppliedPatchSet {
for id in context.has_refs_to_rewrite {
// This should always succeed since instances marked as added in our
// patch should be added without fail.
let mut instance = tree
.get_instance_mut(id)
.expect("Invalid instance ID in deferred property map");
for value in instance.properties_mut().values_mut() {
if let Variant::Ref(referent) = value {
if let Some(&instance_referent) = context.snapshot_id_to_instance_id.get(referent) {
*value = Variant::Ref(instance_referent);
}
}
}
}
// This is to get around the fact that `RojoTre::get_specified_id` borrows
// the tree as immutable, but we need to hold a mutable reference to it.
// Not exactly elegant, but it does the job.
let mut real_rewrites = Vec::new();
for (id, map) in context.attribute_refs_to_rewrite {
for (prop_name, prop_value) in map {
if let Some(target) = tree.get_specified_id(&RojoRef::new(prop_value)) {
real_rewrites.push((prop_name, Variant::Ref(target)))
}
}
let mut instance = tree
.get_instance_mut(id)
.expect("Invalid instance ID in deferred attribute ref map");
instance.properties_mut().extend(real_rewrites.drain(..));
}
context.applied_patch_set
}
fn apply_remove_instance(context: &mut PatchApplyContext, tree: &mut RojoTree, removed_id: Ref) {
tree.remove(removed_id);
context.applied_patch_set.removed.push(removed_id);
}
fn apply_add_child(
context: &mut PatchApplyContext,
tree: &mut RojoTree,
parent_id: Ref,
mut snapshot: InstanceSnapshot,
) {
let snapshot_id = snapshot.snapshot_id;
let children = take(&mut snapshot.children);
// If an object we're adding has a non-null referent, we'll note this
// instance down as needing to be revisited later.
let has_refs = snapshot.properties.values().any(|value| match value {
Variant::Ref(value) => value.is_some(),
_ => false,
});
let id = tree.insert_instance(parent_id, snapshot);
context.applied_patch_set.added.push(id);
if has_refs {
context.has_refs_to_rewrite.insert(id);
}
if snapshot_id.is_some() {
context.snapshot_id_to_instance_id.insert(snapshot_id, id);
}
for child in children {
apply_add_child(context, tree, id, child);
}
defer_ref_properties(tree, id, context);
}
fn apply_update_child(context: &mut PatchApplyContext, tree: &mut RojoTree, patch: PatchUpdate) {
let mut applied_patch = AppliedPatchUpdate::new(patch.id);
if let Some(metadata) = patch.changed_metadata {
tree.update_metadata(patch.id, metadata.clone());
applied_patch.changed_metadata = Some(metadata);
}
let mut instance = match tree.get_instance_mut(patch.id) {
Some(instance) => instance,
None => {
log::warn!(
"Patch misapplication: Instance {:?}, referred to by update patch, did not exist.",
patch.id
);
return;
}
};
if let Some(name) = patch.changed_name {
*instance.name_mut() = name.clone();
applied_patch.changed_name = Some(name);
}
if let Some(class_name) = patch.changed_class_name {
*instance.class_name_mut() = class_name.clone();
applied_patch.changed_class_name = Some(class_name);
}
for (key, property_entry) in patch.changed_properties {
match property_entry {
// Ref values need to be potentially rewritten from snapshot IDs to
// instance IDs if they referred to an instance that was created as
// part of this patch.
Some(Variant::Ref(referent)) => {
if referent.is_none() {
continue;
}
// If our ID is not found in this map, then it either refers to
// an existing instance NOT added by this patch, or there was an
// error. See `PatchApplyContext::snapshot_id_to_instance_id`
// for more info.
let new_referent = context
.snapshot_id_to_instance_id
.get(&referent)
.copied()
.unwrap_or(referent);
instance
.properties_mut()
.insert(key.clone(), Variant::Ref(new_referent));
}
Some(ref value) => {
instance.properties_mut().insert(key.clone(), value.clone());
}
None => {
instance.properties_mut().remove(&key);
}
}
applied_patch.changed_properties.insert(key, property_entry);
}
defer_ref_properties(tree, patch.id, context);
context.applied_patch_set.updated.push(applied_patch)
}
/// Calculates manually-specified Ref properties and marks them in the provided
/// `PatchApplyContext` to be rewritten at the end of the patch application
/// process.
///
/// Currently, this only uses attributes but it can easily handle rewriting
/// referents in other ways too!
fn defer_ref_properties(tree: &mut RojoTree, id: Ref, context: &mut PatchApplyContext) {
let instance = tree
.get_instance(id)
.expect("Instances should exist when calculating deferred refs");
let attributes = match instance.properties().get("Attributes") {
Some(Variant::Attributes(attrs)) => attrs,
_ => return,
};
let mut attr_id = None;
for (attr_name, attr_value) in attributes.iter() {
if attr_name == REF_ID_ATTRIBUTE_NAME {
if let Variant::String(specified_id) = attr_value {
attr_id = Some(RojoRef::new(specified_id.clone()));
} else if let Variant::BinaryString(specified_id) = attr_value {
if let Ok(str) = std::str::from_utf8(specified_id.as_ref()) {
attr_id = Some(RojoRef::new(str.to_string()))
} else {
log::error!("Specified IDs must be valid UTF-8 strings.")
}
} else {
log::warn!(
"Attribute {attr_name} is of type {:?} when it was \
expected to be a String",
attr_value.ty()
)
}
}
if let Some(prop_name) = attr_name.strip_prefix(REF_POINTER_ATTRIBUTE_PREFIX) {
if let Variant::String(prop_value) = attr_value {
context
.attribute_refs_to_rewrite
.insert(id, (prop_name.to_owned(), prop_value.clone()));
} else if let Variant::BinaryString(prop_value) = attr_value {
if let Ok(str) = std::str::from_utf8(prop_value.as_ref()) {
context
.attribute_refs_to_rewrite
.insert(id, (prop_name.to_owned(), str.to_string()));
} else {
log::error!("IDs specified by referent property attributes must be valid UTF-8 strings.")
}
} else {
log::warn!(
"Attribute {attr_name} is of type {:?} when it was \
expected to be a String",
attr_value.ty()
)
}
}
}
if let Some(specified_id) = attr_id {
tree.set_specified_id(id, specified_id);
}
}
#[cfg(test)]
mod test {
use super::*;
use std::borrow::Cow;
use maplit::hashmap;
use rbx_dom_weak::types::Variant;
use super::super::PatchAdd;
#[test]
fn add_from_empty() {
let _ = env_logger::try_init();
let mut tree = RojoTree::new(InstanceSnapshot::new());
let root_id = tree.get_root_id();
let snapshot = InstanceSnapshot {
snapshot_id: Ref::none(),
metadata: Default::default(),
name: Cow::Borrowed("Foo"),
class_name: Cow::Borrowed("Bar"),
properties: hashmap! {
"Baz".to_owned() => Variant::Int32(5),
},
children: Vec::new(),
};
let patch_set = PatchSet {
added_instances: vec![PatchAdd {
parent_id: root_id,
instance: snapshot.clone(),
}],
..Default::default()
};
apply_patch_set(&mut tree, patch_set);
let root_instance = tree.get_instance(root_id).unwrap();
let child_id = root_instance.children()[0];
let child_instance = tree.get_instance(child_id).unwrap();
assert_eq!(child_instance.name(), &snapshot.name);
assert_eq!(child_instance.class_name(), &snapshot.class_name);
assert_eq!(child_instance.properties(), &snapshot.properties);
assert!(child_instance.children().is_empty());
}
#[test]
fn update_existing() {
let _ = env_logger::try_init();
let mut tree = RojoTree::new(
InstanceSnapshot::new()
.class_name("OldClassName")
.name("OldName")
.property("Foo", 7i32)
.property("Bar", 3i32)
.property("Unchanged", -5i32),
);
let root_id = tree.get_root_id();
let patch = PatchUpdate {
id: root_id,
changed_name: Some("Foo".to_owned()),
changed_class_name: Some("NewClassName".to_owned()),
changed_properties: hashmap! {
// The value of Foo has changed
"Foo".to_owned() => Some(Variant::Int32(8)),
// Bar has been deleted
"Bar".to_owned() => None,
// Baz has been added
"Baz".to_owned() => Some(Variant::Int32(10)),
},
changed_metadata: None,
};
let patch_set = PatchSet {
updated_instances: vec![patch],
..Default::default()
};
apply_patch_set(&mut tree, patch_set);
let expected_properties = hashmap! {
"Foo".to_owned() => Variant::Int32(8),
"Baz".to_owned() => Variant::Int32(10),
"Unchanged".to_owned() => Variant::Int32(-5),
};
let root_instance = tree.get_instance(root_id).unwrap();
assert_eq!(root_instance.name(), "Foo");
assert_eq!(root_instance.class_name(), "NewClassName");
assert_eq!(root_instance.properties(), &expected_properties);
}
}