hugo/hugolib/pageCache_test.go
Bjørn Erik Pedersen a9c5133a77 Fix data races in sorting and Reverse
The custom sort functions used from the templates had some subtle data race- and related issues,
especially when used in the single page template.

This commit fixes this by making copies and protect the read and writes with a RWMutex.

The results are cached (it will typically be invoked *number of pages* times with exactly the same data).

This is, not surprisingly, also faster:

```
benchmark                           old ns/op     new ns/op     delta
BenchmarkSortByWeightAndReverse     14228         491           -96.55%

benchmark                           old allocs     new allocs     delta
BenchmarkSortByWeightAndReverse     1              0              -100.00%

benchmark                           old bytes     new bytes     delta
BenchmarkSortByWeightAndReverse     32            0             -100.00%
```

Fixes #1293
2015-07-23 12:43:57 +02:00

60 lines
1.2 KiB
Go

package hugolib
import (
"fmt"
"github.com/stretchr/testify/assert"
"sync"
"sync/atomic"
"testing"
)
func TestPageCache(t *testing.T) {
c1 := newPageCache()
changeFirst := func(p Pages) {
p[0].Description = "changed"
}
var o1 uint64 = 0
var o2 uint64 = 0
var wg sync.WaitGroup
var l1 sync.Mutex
var l2 sync.Mutex
var testPageSets []Pages
for j := 0; j < 50; j++ {
testPageSets = append(testPageSets, createSortTestPages(j+1))
}
for i := 0; i < 100; i++ {
wg.Add(1)
go func() {
defer wg.Done()
for j, pages := range testPageSets {
msg := fmt.Sprintf("Go %d %d %d %d", i, j, o1, o2)
l1.Lock()
p, c := c1.get("k1", pages, nil)
assert.Equal(t, !atomic.CompareAndSwapUint64(&o1, uint64(j), uint64(j+1)), c, "c1: "+msg)
l1.Unlock()
p2, c2 := c1.get("k1", p, nil)
assert.True(t, c2)
assert.True(t, probablyEqualPages(p, p2))
assert.True(t, probablyEqualPages(p, pages))
assert.NotNil(t, p, msg)
l2.Lock()
p3, c3 := c1.get("k2", pages, changeFirst)
assert.Equal(t, !atomic.CompareAndSwapUint64(&o2, uint64(j), uint64(j+1)), c3, "c3: "+msg)
l2.Unlock()
assert.NotNil(t, p3, msg)
assert.Equal(t, p3[0].Description, "changed", msg)
}
}()
}
wg.Wait()
}