Adding upstream version 1.22.1.upstream/1.22.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 66 insertions, 0 deletions

diff --git a/src/maps/maps.go b/src/maps/maps.go
new file mode 100644
index 0000000..befde18
--- /dev/null
+++ b/src/maps/maps.go
@@ -0,0 +1,66 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package maps defines various functions useful with maps of any type.
+package maps
+
+// Equal reports whether two maps contain the same key/value pairs.
+// Values are compared using ==.
+func Equal[M1, M2 ~map[K]V, K, V comparable](m1 M1, m2 M2) bool {
+	if len(m1) != len(m2) {
+		return false
+	}
+	for k, v1 := range m1 {
+		if v2, ok := m2[k]; !ok || v1 != v2 {
+			return false
+		}
+	}
+	return true
+}
+
+// EqualFunc is like Equal, but compares values using eq.
+// Keys are still compared with ==.
+func EqualFunc[M1 ~map[K]V1, M2 ~map[K]V2, K comparable, V1, V2 any](m1 M1, m2 M2, eq func(V1, V2) bool) bool {
+	if len(m1) != len(m2) {
+		return false
+	}
+	for k, v1 := range m1 {
+		if v2, ok := m2[k]; !ok || !eq(v1, v2) {
+			return false
+		}
+	}
+	return true
+}
+
+// clone is implemented in the runtime package.
+func clone(m any) any
+
+// Clone returns a copy of m.  This is a shallow clone:
+// the new keys and values are set using ordinary assignment.
+func Clone[M ~map[K]V, K comparable, V any](m M) M {
+	// Preserve nil in case it matters.
+	if m == nil {
+		return nil
+	}
+	return clone(m).(M)
+}
+
+// Copy copies all key/value pairs in src adding them to dst.
+// When a key in src is already present in dst,
+// the value in dst will be overwritten by the value associated
+// with the key in src.
+func Copy[M1 ~map[K]V, M2 ~map[K]V, K comparable, V any](dst M1, src M2) {
+	for k, v := range src {
+		dst[k] = v
+	}
+}
+
+// DeleteFunc deletes any key/value pairs from m for which del returns true.
+func DeleteFunc[M ~map[K]V, K comparable, V any](m M, del func(K, V) bool) {
+	for k, v := range m {
+		if del(k, v) {
+			delete(m, k)
+		}
+	}
+}