vendor/github.com/google/go-cmp/cmp/reporter.go

   1 // Copyright 2017, The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE.md file.
   4
   5 package cmp
   6
   7 import (
   8         "fmt"
   9         "reflect"
  10         "strings"
  11
  12         "github.com/google/go-cmp/cmp/internal/value"
  13 )
  14
  15 type defaultReporter struct {
  16         Option
  17         diffs  []string // List of differences, possibly truncated
  18         ndiffs int      // Total number of differences
  19         nbytes int      // Number of bytes in diffs
  20         nlines int      // Number of lines in diffs
  21 }
  22
  23 var _ reporter = (*defaultReporter)(nil)
  24
  25 func (r *defaultReporter) Report(x, y reflect.Value, eq bool, p Path) {
  26         if eq {
  27                 return // Ignore equal results
  28         }
  29         const maxBytes = 4096
  30         const maxLines = 256
  31         r.ndiffs++
  32         if r.nbytes < maxBytes && r.nlines < maxLines {
  33                 sx := value.Format(x, value.FormatConfig{UseStringer: true})
  34                 sy := value.Format(y, value.FormatConfig{UseStringer: true})
  35                 if sx == sy {
  36                         // Unhelpful output, so use more exact formatting.
  37                         sx = value.Format(x, value.FormatConfig{PrintPrimitiveType: true})
  38                         sy = value.Format(y, value.FormatConfig{PrintPrimitiveType: true})
  39                 }
  40                 s := fmt.Sprintf("%#v:\n\t-: %s\n\t+: %s\n", p, sx, sy)
  41                 r.diffs = append(r.diffs, s)
  42                 r.nbytes += len(s)
  43                 r.nlines += strings.Count(s, "\n")
  44         }
  45 }
  46
  47 func (r *defaultReporter) String() string {
  48         s := strings.Join(r.diffs, "")
  49         if r.ndiffs == len(r.diffs) {
  50                 return s
  51         }
  52         return fmt.Sprintf("%s... %d more differences ...", s, r.ndiffs-len(r.diffs))
  53 }