Fix copy/paste of empty newlines again

Fixes: go-gitea#19331
Regressed by: go-gitea#18270

Needed to do another newline addition to the Chroma output HTML to get
copy/paste work again. The previous replacement conditions are probably
obsolete, but as I'm not 100% sure, I opted to keep them.

Specifically, the Chroma HTML change mentioned in
go-gitea#18270 (comment)
broke our previous newline replacement for such empty lines.

Also included are a few changes to make the test more pleasant to work
with.

go.mod

@@ -206,6 +206,7 @@ require (
 	github.com/kr/pretty v0.3.0 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/libdns/libdns v0.2.1 // indirect
+	github.com/lithammer/dedent v1.1.0 // indirect
 	github.com/magiconair/properties v1.8.5 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
 	github.com/markbates/going v1.0.0 // indirect

go.sum

@@ -1086,6 +1086,8 @@ github.com/libdns/libdns v0.2.1 h1:Wu59T7wSHRgtA0cfxC+n1c/e+O3upJGWytknkmFEDis=
 github.com/libdns/libdns v0.2.1/go.mod h1:yQCXzk1lEZmmCPa857bnk4TsOiqYasqpyOEeSObbb40=
 github.com/lightstep/lightstep-tracer-common/golang/gogo v0.0.0-20190605223551-bc2310a04743/go.mod h1:qklhhLq1aX+mtWk9cPHPzaBjWImj5ULL6C7HFJtXQMM=
 github.com/lightstep/lightstep-tracer-go v0.18.1/go.mod h1:jlF1pusYV4pidLvZ+XD0UBX0ZE6WURAspgAczcDHrL4=
+github.com/lithammer/dedent v1.1.0 h1:VNzHMVCBNG1j0fh3OrsFRkVUwStdDArbgBWoPAffktY=
+github.com/lithammer/dedent v1.1.0/go.mod h1:jrXYCQtgg0nJiN+StA2KgR7w6CiQNv9Fd/Z9BP0jIOc=
 github.com/lunny/dingtalk_webhook v0.0.0-20171025031554-e3534c89ef96 h1:uNwtsDp7ci48vBTTxDuwcoTXz4lwtDTe7TjCQ0noaWY=
 github.com/lunny/dingtalk_webhook v0.0.0-20171025031554-e3534c89ef96/go.mod h1:mmIfjCSQlGYXmJ95jFN84AkQFnVABtKuJL8IrzwvUKQ=
 github.com/lunny/log v0.0.0-20160921050905-7887c61bf0de/go.mod h1:3q8WtuPQsoRbatJuy3nvq/hRSvuBJrHHr+ybPPiNvHQ=

modules/highlight/highlight.go

@@ -203,6 +203,8 @@ func File(numLines int, fileName, language string, code []byte) []string {
 			content = "\n"
 		} else if content == `</span><span class="w">` {
 			content += "\n</span>"
+		} else if content == `</span></span><span class="line"><span class="cl">` {
+			content += "\n"
 		}
 		content = strings.TrimSuffix(content, `<span class="w">`)
 		content = strings.TrimPrefix(content, `</span>`)

modules/highlight/highlight_test.go

@@ -5,11 +5,13 @@
 package highlight
 
 import (
-	"reflect"
+	"strings"
 	"testing"
 
 	"code.gitea.io/gitea/modules/setting"
 
+	"github.com/lithammer/dedent"
+	"github.com/stretchr/testify/assert"
 	"gopkg.in/ini.v1"
 )
 
@@ -20,83 +22,83 @@ func TestFile(t *testing.T) {
 		numLines int
 		fileName string
 		code     string
-		want     []string
+		want     string
 	}{
 		{
 			name:     ".drone.yml",
 			numLines: 12,
 			fileName: ".drone.yml",
-			code: `kind: pipeline
-name: default
+			code: strings.TrimSpace(dedent.Dedent(`
+				kind: pipeline
+				name: default
 
-steps:
-- name: test
-	image: golang:1.13
-	environment:
-		GOPROXY: https://goproxy.cn
-	commands:
-	- go get -u
-	- go build -v
-	- go test -v -race -coverprofile=coverage.txt -covermode=atomic
-`,
-			want: []string{
-				`<span class="line"><span class="cl"><span class="nt">kind</span><span class="p">:</span><span class="w"> </span><span class="l">pipeline</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span><span class="nt">name</span><span class="p">:</span><span class="w"> </span><span class="l">default</span>`,
-				`</span></span><span class="line"><span class="cl">`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span><span class="nt">steps</span><span class="p">:</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span>- <span class="nt">name</span><span class="p">:</span><span class="w"> </span><span class="l">test</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">image</span><span class="p">:</span><span class="w"> </span><span class="l">golang:1.13</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">environment</span><span class="p">:</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span><span class="w">		</span><span class="nt">GOPROXY</span><span class="p">:</span><span class="w"> </span><span class="l">https://goproxy.cn</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">commands</span><span class="p">:</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span><span class="w">	</span>- <span class="l">go get -u</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span>- <span class="l">go build -v</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span>- <span class="l">go test -v -race -coverprofile=coverage.txt -covermode=atomic</span><span class="w">
-</span></span></span>`,
-				`<span class="w">
-</span>`,
-			},
+				steps:
+				- name: test
+					image: golang:1.13
+					environment:
+						GOPROXY: https://goproxy.cn
+					commands:
+					- go get -u
+					- go build -v
+					- go test -v -race -coverprofile=coverage.txt -covermode=atomic
+			`)),
+			want: strings.TrimSpace(dedent.Dedent(`
+				<span class="line"><span class="cl"><span class="nt">kind</span><span class="p">:</span><span class="w"> </span><span class="l">pipeline</span>
+				</span></span><span class="line"><span class="cl"><span class="w"></span><span class="nt">name</span><span class="p">:</span><span class="w"> </span><span class="l">default</span>
+				</span></span><span class="line"><span class="cl">
+				</span></span><span class="line"><span class="cl"><span class="w"></span><span class="nt">steps</span><span class="p">:</span>
+				</span></span><span class="line"><span class="cl"><span class="w"></span>- <span class="nt">name</span><span class="p">:</span><span class="w"> </span><span class="l">test</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">image</span><span class="p">:</span><span class="w"> </span><span class="l">golang:1.13</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">environment</span><span class="p">:</span>
+				</span></span><span class="line"><span class="cl"><span class="w"></span><span class="w">		</span><span class="nt">GOPROXY</span><span class="p">:</span><span class="w"> </span><span class="l">https://goproxy.cn</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">commands</span><span class="p">:</span>
+				</span></span><span class="line"><span class="cl"><span class="w"></span><span class="w">	</span>- <span class="l">go get -u</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span>- <span class="l">go build -v</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span>- <span class="l">go test -v -race -coverprofile=coverage.txt -covermode=atomic</span></span></span>
+			`)),
 		},
 		{
 			name:     ".drone.yml - trailing space",
 			numLines: 13,
 			fileName: ".drone.yml",
-			code: `kind: pipeline
-name: default  ` + `
+			code: strings.Replace(strings.TrimSpace(dedent.Dedent(`
+				kind: pipeline
+				name: default
 
-steps:
-- name: test
-	image: golang:1.13
-	environment:
-		GOPROXY: https://goproxy.cn
-	commands:
-	- go get -u
-	- go build -v
-	- go test -v -race -coverprofile=coverage.txt -covermode=atomic
-	`,
-			want: []string{
-				`<span class="line"><span class="cl"><span class="nt">kind</span><span class="p">:</span><span class="w"> </span><span class="l">pipeline</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span><span class="nt">name</span><span class="p">:</span><span class="w"> </span><span class="l">default  </span>`,
-				`</span></span><span class="line"><span class="cl">`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span><span class="nt">steps</span><span class="p">:</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span>- <span class="nt">name</span><span class="p">:</span><span class="w"> </span><span class="l">test</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">image</span><span class="p">:</span><span class="w"> </span><span class="l">golang:1.13</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">environment</span><span class="p">:</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span><span class="w">		</span><span class="nt">GOPROXY</span><span class="p">:</span><span class="w"> </span><span class="l">https://goproxy.cn</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">commands</span><span class="p">:</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w"></span><span class="w">	</span>- <span class="l">go get -u</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span>- <span class="l">go build -v</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span>- <span class="l">go test -v -race -coverprofile=coverage.txt -covermode=atomic</span>`,
-				`</span></span><span class="line"><span class="cl"><span class="w">	</span></span></span>`,
-			},
+				steps:
+				- name: test
+					image: golang:1.13
+					environment:
+						GOPROXY: https://goproxy.cn
+					commands:
+					- go get -u
+					- go build -v
+					- go test -v -race -coverprofile=coverage.txt -covermode=atomic
+			`))+"\n", "name: default", "name: default  ", 1),
+			want: strings.TrimSpace(dedent.Dedent(`
+				<span class="line"><span class="cl"><span class="nt">kind</span><span class="p">:</span><span class="w"> </span><span class="l">pipeline</span>
+				</span></span><span class="line"><span class="cl"><span class="w"></span><span class="nt">name</span><span class="p">:</span><span class="w"> </span><span class="l">default  </span>
+				</span></span><span class="line"><span class="cl">
+				</span></span><span class="line"><span class="cl"><span class="w"></span><span class="nt">steps</span><span class="p">:</span>
+				</span></span><span class="line"><span class="cl"><span class="w"></span>- <span class="nt">name</span><span class="p">:</span><span class="w"> </span><span class="l">test</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">image</span><span class="p">:</span><span class="w"> </span><span class="l">golang:1.13</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">environment</span><span class="p">:</span>
+				</span></span><span class="line"><span class="cl"><span class="w"></span><span class="w">		</span><span class="nt">GOPROXY</span><span class="p">:</span><span class="w"> </span><span class="l">https://goproxy.cn</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span><span class="nt">commands</span><span class="p">:</span>
+				</span></span><span class="line"><span class="cl"><span class="w"></span><span class="w">	</span>- <span class="l">go get -u</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span>- <span class="l">go build -v</span>
+				</span></span><span class="line"><span class="cl"><span class="w">	</span>- <span class="l">go test -v -race -coverprofile=coverage.txt -covermode=atomic</span>
+				</span></span>
+				<span class="w">
+				</span>
+			`)),
 		},
 	}
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			if got := File(tt.numLines, tt.fileName, "", []byte(tt.code)); !reflect.DeepEqual(got, tt.want) {
-				t.Errorf("File() = %v, want %v", got, tt.want)
-			}
+			got := strings.Join(File(tt.numLines, tt.fileName, "", []byte(tt.code)), "\n")
+			assert.Equal(t, tt.want, got)
 		})
 	}
 }