Update

vendor/github.com/gaissmai/bart/internal/tests/golden/table.go

@@ -0,0 +1,207 @@
+// Copyright (c) 2026 Karl Gaissmaier
+// SPDX-License-Identifier: MIT
+
+package golden
+
+import (
+	"cmp"
+	"fmt"
+	"net/netip"
+	"slices"
+)
+
+// Table is a simple and slow route table, implemented as a slice of prefixes
+// and values as a golden reference for bart.
+type Table[V any] []TableItem[V]
+
+type TableItem[V any] struct {
+	Pfx netip.Prefix
+	Val V
+}
+
+func (g TableItem[V]) String() string {
+	return fmt.Sprintf("(%s, %v)", g.Pfx, g.Val)
+}
+
+func (t *Table[V]) Insert(pfx netip.Prefix, val V) {
+	pfx = pfx.Masked()
+	for i, item := range *t {
+		if item.Pfx == pfx {
+			(*t)[i].Val = val // de-dupe
+			return
+		}
+	}
+	*t = append(*t, TableItem[V]{pfx, val})
+}
+
+func (t *Table[V]) Delete(pfx netip.Prefix) (exists bool) {
+	pfx = pfx.Masked()
+
+	for i, item := range *t {
+		if item.Pfx == pfx {
+			*t = slices.Delete(*t, i, i+1)
+			return true
+		}
+	}
+	return false
+}
+
+func (t Table[V]) AllSorted() []netip.Prefix {
+	var result []netip.Prefix
+
+	for _, item := range t {
+		result = append(result, item.Pfx)
+	}
+	slices.SortFunc(result, cmpPrefix)
+	return result
+}
+
+func (t Table[V]) Get(pfx netip.Prefix) (val V, ok bool) {
+	pfx = pfx.Masked()
+	for _, item := range t {
+		if item.Pfx == pfx {
+			return item.Val, true
+		}
+	}
+	return val, false
+}
+
+func (t *Table[V]) Update(pfx netip.Prefix, cb func(V, bool) V) (val V) {
+	pfx = pfx.Masked()
+	for i, item := range *t {
+		if item.Pfx == pfx {
+			// update val
+			val = cb(item.Val, true)
+			(*t)[i].Val = val
+			return val
+		}
+	}
+	// new val
+	val = cb(val, false)
+
+	*t = append(*t, TableItem[V]{pfx, val})
+	return val
+}
+
+func (ta *Table[V]) Union(tb *Table[V]) {
+	for _, bItem := range *tb {
+		var match bool
+		for i, aItem := range *ta {
+			if aItem.Pfx == bItem.Pfx {
+				(*ta)[i] = bItem
+				match = true
+				break
+			}
+		}
+		if !match {
+			*ta = append(*ta, bItem)
+		}
+	}
+}
+
+func (t Table[V]) Lookup(addr netip.Addr) (val V, ok bool) {
+	bestLen := -1
+
+	for _, item := range t {
+		if item.Pfx.Contains(addr) && item.Pfx.Bits() > bestLen {
+			val = item.Val
+			ok = true
+			bestLen = item.Pfx.Bits()
+		}
+	}
+	return val, ok
+}
+
+func (t Table[V]) LookupPrefix(pfx netip.Prefix) (val V, ok bool) {
+	pfx = pfx.Masked()
+	bestLen := -1
+
+	for _, item := range t {
+		if item.Pfx.Overlaps(pfx) && item.Pfx.Bits() <= pfx.Bits() && item.Pfx.Bits() > bestLen {
+			val = item.Val
+			ok = true
+			bestLen = item.Pfx.Bits()
+		}
+	}
+	return val, ok
+}
+
+func (t Table[V]) LookupPrefixLPM(pfx netip.Prefix) (lpm netip.Prefix, val V, ok bool) {
+	pfx = pfx.Masked()
+	bestLen := -1
+
+	for _, item := range t {
+		if item.Pfx.Overlaps(pfx) && item.Pfx.Bits() <= pfx.Bits() && item.Pfx.Bits() > bestLen {
+			val = item.Val
+			lpm = item.Pfx
+			ok = true
+			bestLen = item.Pfx.Bits()
+		}
+	}
+	return lpm, val, ok
+}
+
+func (t Table[V]) Subnets(pfx netip.Prefix) []netip.Prefix {
+	pfx = pfx.Masked()
+	var result []netip.Prefix
+
+	for _, item := range t {
+		if pfx.Overlaps(item.Pfx) && pfx.Bits() <= item.Pfx.Bits() {
+			result = append(result, item.Pfx)
+		}
+	}
+	slices.SortFunc(result, cmpPrefix)
+	return result
+}
+
+func (t Table[V]) Supernets(pfx netip.Prefix) []netip.Prefix {
+	pfx = pfx.Masked()
+	var result []netip.Prefix
+
+	for _, item := range t {
+		if item.Pfx.Overlaps(pfx) && item.Pfx.Bits() <= pfx.Bits() {
+			result = append(result, item.Pfx)
+		}
+	}
+	slices.SortFunc(result, cmpPrefix)
+	slices.Reverse(result)
+	return result
+}
+
+func (t Table[V]) OverlapsPrefix(pfx netip.Prefix) bool {
+	pfx = pfx.Masked()
+	for _, p := range t {
+		if p.Pfx.Overlaps(pfx) {
+			return true
+		}
+	}
+	return false
+}
+
+func (ta *Table[V]) Overlaps(tb *Table[V]) bool {
+	for _, aItem := range *ta {
+		for _, bItem := range *tb {
+			if aItem.Pfx.Overlaps(bItem.Pfx) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// Sort, inplace by netip.Prefix, all prefixes are in normalized form
+func (t *Table[V]) Sort() {
+	slices.SortFunc(*t, func(a, b TableItem[V]) int {
+		return cmpPrefix(a.Pfx, b.Pfx)
+	})
+}
+
+// cmpPrefix, helper function, compare func for prefix sort,
+// all cidrs are already normalized
+func cmpPrefix(a, b netip.Prefix) int {
+	if cmpAddr := a.Addr().Compare(b.Addr()); cmpAddr != 0 {
+		return cmpAddr
+	}
+
+	return cmp.Compare(a.Bits(), b.Bits())
+}