limitations under the License.
*/

package resolver

import (
	"fmt"

	"k8s.io/apimachinery/pkg/util/sets"
	"k8s.io/kube-openapi/pkg/validation/spec"
)

// PopulateRefs recursively replaces Refs in the schema with the referred one.
// schemaOf is the callback to find the corresponding schema by the ref.
// This function will not mutate the original schema. If the schema needs to be

			// block, then we need to remove the
			// corresponding elements from the block
			// predecessors and phi args
			if reusedBlock {
				// Add p->d edge
				p.Succs[pi] = Edge{d, len(d.Preds)}
				d.Preds = append(d.Preds, Edge{p, pi})

				// Remove p as a predecessor from b.
				b.removePred(i)

				// Update corresponding phi args
				b.removePhiArg(phi, i)

				// splitting occasionally leads to a phi having

		if bx == c {
			break
		}
		copyTo += len(bx.Values)
	}
	c.Values = t

	// replace b->c edge with preds(b) -> c
	c.predstorage[0] = Edge{}
	if len(b.Preds) > len(b.predstorage) {
		c.Preds = b.Preds
	} else {
		c.Preds = append(c.predstorage[:0], b.Preds...)
	}
	for i, e := range c.Preds {
		p := e.b
		p.Succs[e.i] = Edge{c, i}
	}
	f := b.Func
	if f.Entry == b {
		f.Entry = c
	}

	for _, b := range f.Blocks {
		if len(b.Preds) != 2 || len(b.Values) == 0 {
			// TODO: handle more than 2 predecessors, e.g. a || b || c.
			continue
		}

		pb0, b0 := b, b.Preds[0].b
		for len(b0.Succs) == 1 && len(b0.Preds) == 1 {
			pb0, b0 = b0, b0.Preds[0].b
		}
		if b0.Kind != BlockIf {
			continue
		}
		pb1, b1 := b, b.Preds[1].b
		for len(b1.Succs) == 1 && len(b1.Preds) == 1 {
			pb1, b1 = b1, b1.Preds[0].b
		}

		// order, in which the predecessors edges are merged here.
		p, i := b.Preds[0].b, b.Preds[0].i
		s, j := b.Succs[0].b, b.Succs[0].i
		ns := len(s.Preds)
		p.Succs[i] = Edge{s, j}
		s.Preds[j] = Edge{p, i}

		for _, e := range b.Preds[1:] {
			p, i := e.b, e.i
			p.Succs[i] = Edge{s, len(s.Preds)}
			s.Preds = append(s.Preds, Edge{p, i})
		}

		// Attempt to preserve a statement boundary
		if bIsStmt {

git show-ref --tags --heads
cmp stdout .git-refs

-- .git-refs --
ede458df7cd0fdca520df19a33158086a8a68e81 refs/heads/master
9d02800338b8a55be062c838d1f02e0c5780b9eb refs/heads/v2
76a00fb249b7f93091bc2c89a789dab1fc1bc26f refs/heads/v2.3.4
a8205f853c297ad2c3c502ba9a355b35b7dd3ca5 refs/heads/v3
ede458df7cd0fdca520df19a33158086a8a68e81 refs/tags/v1.2.3
b004e48a345a86ed7a2fb7debfa7e0b2f9b0dd91 refs/tags/v1.2.4-annotated

	*LockedFile
	mutex sync.Mutex
	refs  int // Holds read lock refs.
}

// IsClosed - Check if the rlocked file is already closed.
func (r *RLockedFile) IsClosed() bool {
	r.mutex.Lock()
	defer r.mutex.Unlock()
	return r.refs == 0
}

// IncLockRef - is used by called to indicate lock refs.
func (r *RLockedFile) IncLockRef() {
	r.mutex.Lock()
	r.refs++
	r.mutex.Unlock()
}

git show-ref --tags --heads
cmp stdout .git-refs

-- .git-refs --
ed5ffdaa1f5e7e0be6f5ba2d63097026506224f2 refs/heads/master
feed8f518cf4a7215a3b2a8268b8b0746dcbb12d refs/heads/v2
f6abd4e3ed7f2297bc8fd2888bd6d5412e255fcc refs/tags/favorite
5e9e31667ddfe16e9350f4bd00acc933c8cd5e56 refs/tags/start
0de900e0063bcc310ea0621bfbc227a9b4e3b020 refs/tags/v0.0.0
e5ec98b1c15df29e3bd346d538d73b6e8c3b500c refs/tags/v0.0.0-pre1

	// in which the outbound paths from b merge,
	// with no other preds joining them.
	// In these cases, we can reconstruct what the value
	// of any phi in b must be in the successor blocks.

	if len(t.Preds) == 1 && len(t.Succs) == 1 &&
		len(u.Preds) == 1 && len(u.Succs) == 1 &&
		t.Succs[0].b == u.Succs[0].b && len(t.Succs[0].b.Preds) == 2 {
		// p   q
		//  \ /
		//   b
		//  / \
		// t   u
		//  \ /

	var ref, hash string
	if refs["refs/tags/"+rev] != "" {
		ref = "refs/tags/" + rev
		hash = refs[ref]
		// Keep rev as is: tags are assumed not to change meaning.
	} else if refs["refs/heads/"+rev] != "" {
		ref = "refs/heads/" + rev
		hash = refs[ref]
		rev = hash // Replace rev, because meaning of refs/heads/foo can change.
	} else if rev == "HEAD" && refs["HEAD"] != "" {
		ref = "HEAD"
		hash = refs[ref]