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Diffstat (limited to 'src/pkg/reflect/deepequal.go')
-rw-r--r-- | src/pkg/reflect/deepequal.go | 126 |
1 files changed, 0 insertions, 126 deletions
diff --git a/src/pkg/reflect/deepequal.go b/src/pkg/reflect/deepequal.go deleted file mode 100644 index a483135b0..000000000 --- a/src/pkg/reflect/deepequal.go +++ /dev/null @@ -1,126 +0,0 @@ -// Copyright 2009 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. - -// Deep equality test via reflection - -package reflect - -// During deepValueEqual, must keep track of checks that are -// in progress. The comparison algorithm assumes that all -// checks in progress are true when it reencounters them. -// Visited are stored in a map indexed by 17 * a1 + a2; -type visit struct { - a1 uintptr - a2 uintptr - typ Type - next *visit -} - -// Tests for deep equality using reflected types. The map argument tracks -// comparisons that have already been seen, which allows short circuiting on -// recursive types. -func deepValueEqual(v1, v2 Value, visited map[uintptr]*visit, depth int) (b bool) { - if !v1.IsValid() || !v2.IsValid() { - return v1.IsValid() == v2.IsValid() - } - if v1.Type() != v2.Type() { - return false - } - - // if depth > 10 { panic("deepValueEqual") } // for debugging - - if v1.CanAddr() && v2.CanAddr() { - addr1 := v1.UnsafeAddr() - addr2 := v2.UnsafeAddr() - if addr1 > addr2 { - // Canonicalize order to reduce number of entries in visited. - addr1, addr2 = addr2, addr1 - } - - // Short circuit if references are identical ... - if addr1 == addr2 { - return true - } - - // ... or already seen - h := 17*addr1 + addr2 - seen := visited[h] - typ := v1.Type() - for p := seen; p != nil; p = p.next { - if p.a1 == addr1 && p.a2 == addr2 && p.typ == typ { - return true - } - } - - // Remember for later. - visited[h] = &visit{addr1, addr2, typ, seen} - } - - switch v1.Kind() { - case Array: - if v1.Len() != v2.Len() { - return false - } - for i := 0; i < v1.Len(); i++ { - if !deepValueEqual(v1.Index(i), v2.Index(i), visited, depth+1) { - return false - } - } - return true - case Slice: - if v1.Len() != v2.Len() { - return false - } - for i := 0; i < v1.Len(); i++ { - if !deepValueEqual(v1.Index(i), v2.Index(i), visited, depth+1) { - return false - } - } - return true - case Interface: - if v1.IsNil() || v2.IsNil() { - return v1.IsNil() == v2.IsNil() - } - return deepValueEqual(v1.Elem(), v2.Elem(), visited, depth+1) - case Ptr: - return deepValueEqual(v1.Elem(), v2.Elem(), visited, depth+1) - case Struct: - for i, n := 0, v1.NumField(); i < n; i++ { - if !deepValueEqual(v1.Field(i), v2.Field(i), visited, depth+1) { - return false - } - } - return true - case Map: - if v1.Len() != v2.Len() { - return false - } - for _, k := range v1.MapKeys() { - if !deepValueEqual(v1.MapIndex(k), v2.MapIndex(k), visited, depth+1) { - return false - } - } - return true - default: - // Normal equality suffices - return v1.Interface() == v2.Interface() - } - - panic("Not reached") -} - -// DeepEqual tests for deep equality. It uses normal == equality where possible -// but will scan members of arrays, slices, and fields of structs. It correctly -// handles recursive types. -func DeepEqual(a1, a2 interface{}) bool { - if a1 == nil || a2 == nil { - return a1 == a2 - } - v1 := ValueOf(a1) - v2 := ValueOf(a2) - if v1.Type() != v2.Type() { - return false - } - return deepValueEqual(v1, v2, make(map[uintptr]*visit), 0) -} |