// Copyright 2017, 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 cmp

// defaultReporter implements the reporter interface.
//
// As Equal serially calls the PushStep, Report, and PopStep methods, the
// defaultReporter constructs a tree-based representation of the compared value
// and the result of each comparison (see valueNode).
//
// When the String method is called, the FormatDiff method transforms the
// valueNode tree into a textNode tree, which is a tree-based representation
// of the textual output (see textNode).
//
// Lastly, the textNode.String method produces the final report as a string.
type defaultReporter struct {
	root *valueNode
	curr *valueNode
}

func ( *defaultReporter) ( PathStep) {
	.curr = .curr.PushStep()
	if .root == nil {
		.root = .curr
	}
}
func ( *defaultReporter) ( Result) {
	.curr.Report()
}
func ( *defaultReporter) () {
	.curr = .curr.PopStep()
}

// String provides a full report of the differences detected as a structured
// literal in pseudo-Go syntax. String may only be called after the entire tree
// has been traversed.
func ( *defaultReporter) () string {
	assert(.root != nil && .curr == nil)
	if .root.NumDiff == 0 {
		return ""
	}
	 := new(pointerReferences)
	 := formatOptions{}.FormatDiff(.root, )
	resolveReferences()
	return .String()
}

func ( bool) {
	if ! {
		panic("assertion failure")
	}
}