engine: switched to multilinediff package (#47)

Improve diff readability by switching to the multilinediff package which
has a much more readable two-column diff setup. Eventually this package
will be improved to have coloured output, which this tool can benefit
from when it's ready.

engine/engine.go

@@ -18,8 +18,8 @@ import (
 	"fmt"
 	"os"
 
+	"github.com/RageCage64/multilinediff"
 	"github.com/google/yamlfmt"
-	"github.com/google/yamlfmt/internal/diff"
 	"github.com/google/yamlfmt/internal/paths"
 )
 
@@ -91,7 +91,7 @@ func (e *Engine) LintFile(path string) error {
 	if err != nil {
 		return err
 	}
-	diffContent := diff.MultilineStringDiff(string(yamlBytes), string(formatted))
+	diffContent := multilinediff.MultilineDiff(string(yamlBytes), string(formatted), "\n")
 	if diffContent != "" {
 		return fmt.Errorf(diffContent)
 	}
@@ -130,6 +130,6 @@ func (e *Engine) DryRunFile(path string) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	diffContent := diff.MultilineStringDiff(string(yamlBytes), string(formatted))
+	diffContent := multilinediff.MultilineDiff(string(yamlBytes), string(formatted), "\n")
 	return diffContent, nil
 }

go.mod

@@ -4,8 +4,10 @@ go 1.19
 
 require (
 	github.com/RageCage64/go-utf8-codepoint-converter v0.1.0
+	github.com/RageCage64/multilinediff v0.1.0
 	github.com/bmatcuk/doublestar/v4 v4.2.0
-	github.com/google/go-cmp v0.5.8
 	github.com/mitchellh/mapstructure v1.5.0
 	gopkg.in/yaml.v3 v3.0.1
 )
+
+require github.com/google/go-cmp v0.5.9 // indirect

go.sum

@@ -1,9 +1,11 @@
 github.com/RageCage64/go-utf8-codepoint-converter v0.1.0 h1:6GreQRSQApXW1sgeFXMBLDdxSC6DCzu4lKBS/LEyrSA=
 github.com/RageCage64/go-utf8-codepoint-converter v0.1.0/go.mod h1:asNWDxR7n0QIQyZNYTlpNk6Dg7GkUnxtCXho987uen8=
+github.com/RageCage64/multilinediff v0.1.0 h1:P9Iht5Vj4SHSmTJhQPJnySzTlX/cpL99kN3RJxejipQ=
+github.com/RageCage64/multilinediff v0.1.0/go.mod h1:pKr+KLgP0gvRzA+yv0/IUaYQuBYN1ucWysvsL58aMP0=
 github.com/bmatcuk/doublestar/v4 v4.2.0 h1:Qu+u9wR3Vd89LnlLMHvnZ5coJMWKQamqdz9/p5GNthA=
 github.com/bmatcuk/doublestar/v4 v4.2.0/go.mod h1:xBQ8jztBU6kakFMg+8WGxn0c6z1fTSPVIjEY1Wr7jzc=
-github.com/google/go-cmp v0.5.8 h1:e6P7q2lk1O+qJJb4BtCQXlK8vWEO8V1ZeuEdJNOqZyg=
-github.com/google/go-cmp v0.5.8/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY=
 github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=