Implement "gap" property for flexbox algorithm (#248)

* Consistently use camelCase in test_helper.js

* Add support for parsing grid style properties to test_helper.js

* Add support for generating Taffy Grid styles in tests to gentest main.rs

* Add generated tests for flexbox gap

* Add gap property to style module

* Implement gap property for flexbox algorthim

* Add gap to changelog

* Add tests for percentage gutters with defined parent node size

* Add test for percentage gap with undefined parent node size

* Fix percentage main-axis column gaps in containers with undefined main size

* Gentest: delete generated tests before recreating (ensures tests are deleted if fixture is deleted)

* Cargo fmt

* Add test for percentage row gap in a flex-wrap container with undefined height

* gentest: fix clippy warnings

* Add more small benchmarks + harmonise benchmarks names with 0.1 benchmarks

* Create helper function for summing axis total gap

* Add flexbox-gap example

* Add test for fixed gaps with undefined parent size

* Remove commented out code in gentest script

Co-authored-by: Alice Cecile <[email protected]>

* Use Size::UNDEFINED as the default for the gap style property

* Fix fixed size column gaps with undefined parent width

* Add additional flexbox gap test

Co-authored-by: Alice Cecile <[email protected]>

RELEASES.md

@@ -12,6 +12,7 @@
 - Added support for `AlignContent::SpaceEvenly`
 - Added `AvailableSpace` enum
 - Added `debug` modules with a `print_tree` function, which prints a debug representation of the computed layout for a tree of nodes.
+- Added support for `gap` property (shorthand form of `row-gap`/`column-gap`)
 
 ### 0.2.0 Changed
 

benches/big_tree.rs

@@ -126,9 +126,30 @@ fn taffy_benchmarks(c: &mut Criterion) {
     drop(group);
 
     // Decrease sample size, because the tasks take longer
-    let mut group = c.benchmark_group("big trees");
+    let mut group = c.benchmark_group("big trees (wide)");
     group.sample_size(10);
 
+    group.bench_function("10 nodes (2-level hierarchy)", |b| {
+        let mut taffy = Taffy::new();
+        let root = build_flat_hierarchy(&mut taffy, 10);
+
+        b.iter(|| taffy.compute_layout(root, Size::MAX_CONTENT).unwrap())
+    });
+
+    group.bench_function("100 nodes (2-level hierarchy)", |b| {
+        let mut taffy = Taffy::new();
+        let root = build_flat_hierarchy(&mut taffy, 100);
+
+        b.iter(|| taffy.compute_layout(root, Size::MAX_CONTENT).unwrap())
+    });
+
+    group.bench_function("1_000 nodes (2-level hierarchy)", |b| {
+        let mut taffy = Taffy::new();
+        let root = build_flat_hierarchy(&mut taffy, 1_000);
+
+        b.iter(|| taffy.compute_layout(root, Size::MAX_CONTENT).unwrap())
+    });
+
     group.bench_function("10_000 nodes (2-level hierarchy)", |b| {
         let mut taffy = Taffy::new();
         let root = build_flat_hierarchy(&mut taffy, 10_000);
@@ -150,6 +171,12 @@ fn taffy_benchmarks(c: &mut Criterion) {
         b.iter(|| taffy.compute_layout(root, Size::MAX_CONTENT).unwrap())
     });
 
+    drop(group);
+
+    // Decrease sample size, because the tasks take longer
+    let mut group = c.benchmark_group("big trees (deep)");
+    group.sample_size(10);
+
     group.bench_function("4000 nodes (12-level hierarchy)", |b| {
         let mut taffy = Taffy::new();
         let root = build_deep_hierarchy(&mut taffy, 4000, 2);