append possibly assigns to a wrong variable CRT-D0001
Bug risk
Minor
8 months ago
—
3 years old
append result not assigned to the same slice
334 finalFilters := b.filters
335 conf := solver.GetSchedulerConfig()
336 if witnessFilter := filter.NewPlacementWitnessSafeguard(b.GetName(), conf, solver.GetBasicCluster(), solver.GetRuleManager(), solver.Region, solver.Source, solver.fit); witnessFilter != nil {
337 finalFilters = append(b.filters, witnessFilter)338 }
339 targets = filter.SelectTargetStores(targets, finalFilters, conf, collector, b.filterCounter)
340 sort.Slice(targets, func(i, j int) bool {append result not assigned to the same slice
508func (conf *hotRegionSchedulerConfig) applyPrioritiesConfig(p prioritiesConfig) {
509 conf.ReadPriorities = append(p.read[:0:0], p.read...)
510 conf.WriteLeaderPriorities = append(p.writeLeader[:0:0], p.writeLeader...)
511 conf.WritePeerPriorities = append(p.writePeer[:0:0], p.writePeer...)512}
513
514func getReadPriorities(c *prioritiesConfig) []string {append result not assigned to the same slice
507
508func (conf *hotRegionSchedulerConfig) applyPrioritiesConfig(p prioritiesConfig) {
509 conf.ReadPriorities = append(p.read[:0:0], p.read...)
510 conf.WriteLeaderPriorities = append(p.writeLeader[:0:0], p.writeLeader...)511 conf.WritePeerPriorities = append(p.writePeer[:0:0], p.writePeer...)
512}
513append result not assigned to the same slice
506}
507
508func (conf *hotRegionSchedulerConfig) applyPrioritiesConfig(p prioritiesConfig) {
509 conf.ReadPriorities = append(p.read[:0:0], p.read...)510 conf.WriteLeaderPriorities = append(p.writeLeader[:0:0], p.writeLeader...)
511 conf.WritePeerPriorities = append(p.writePeer[:0:0], p.writePeer...)
512}append result not assigned to the same slice
534 finalFilters := l.filters
535 conf := solver.GetSchedulerConfig()
536 if leaderFilter := filter.NewPlacementLeaderSafeguard(l.GetName(), conf, solver.GetBasicCluster(), solver.GetRuleManager(), solver.Region, solver.Source, false /*allowMoveLeader*/); leaderFilter != nil {
537 finalFilters = append(l.filters, leaderFilter)538 }
539 target := filter.NewCandidates([]*core.StoreInfo{solver.Target}).
540 FilterTarget(conf, nil, l.filterCounter, finalFilters...).
Description
The builtin function append returns the updated slice after the append operation.
This resulting slice is usually assigned back to the same variable that contained
the original slice to which new values were appended.
Bad practice
x = []int{1, 3, 5}
append(x, 7) // returns the value []int{1, 3, 5, 7}. This is usually assigned back to x
x := []int{}
y := []int{}
x = append(y, 1) // possibly wrong
Recommended
x = []int{1, 3, 5}
x = append(x, 7)
x := []int{}
y := []int{}
y = append(y, 1) // append 1 to y