93bf16d · dodrio · git.iko.soy

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Assert that keys are unique among siblings in debug mode

93bf16dNick Fitzgerald8 years ago

src/diff.rs+22

@@ -275,6 +275,28 @@ fn diff_keyed_children(

275 new: &[Node],

276 cached_roots: &mut FxHashSet<CacheId>,

277) {

278+ if cfg!(debug_assertions) {

279+ let mut keys = FxHashSet::default();

280+ let mut assert_unique_keys = |children: &[Node]| {

281+ keys.clear();

282+ for child in children {

283+ let key = child.key();

284+ debug_assert!(

285+ key.is_some(),

286+ "if any sibling is keyed, all siblings must be keyed"

287+ );

288+ keys.insert(key);

289+ }

290+ debug_assert_eq!(

291+ children.len(),

292+ keys.len(),

293+ "keyed siblings must each have a unique key"

294+ );

295+ };

296+ assert_unique_keys(old);

297+ assert_unique_keys(new);

298+ }

299+

278 // First up, we diff all the nodes with the same key at the beginning of the

300 // First up, we diff all the nodes with the same key at the beginning of the

279 // children.

301 // children.

280 //

302 //