fix: include last line in file previews with no trailing newline

modules/markup/file_preview.go

@@ -7,6 +7,7 @@ import (
 	"bufio"
 	"bytes"
 	"html/template"
+	"io"
 	"regexp"
 	"slices"
 	"strconv"
@@ -184,10 +185,12 @@ func newFilePreview(ctx *RenderContext, node *html.Node, locale translation.Loca
 	lineBuffer := new(bytes.Buffer)
 	for i := 0; i < lineCount; i++ {
 		buf, err := reader.ReadBytes('\n')
+		if err == nil || err == io.EOF {
+			lineBuffer.Write(buf)
+		}
 		if err != nil {
 			break
 		}
-		lineBuffer.Write(buf)
 	}
 
 	// highlight the file...

modules/markup/html_test.go

@@ -688,10 +688,10 @@ func TestRender_FilePreview(t *testing.T) {
 			require.NoError(t, err)
 			defer gitRepo.Close()
 
-			commit, err := gitRepo.GetCommit("HEAD")
+			commit, err := gitRepo.GetCommit(commitSha)
 			require.NoError(t, err)
 
-			blob, err := commit.GetBlobByPath("path/to/file.go")
+			blob, err := commit.GetBlobByPath(filePath)
 			require.NoError(t, err)
 
 			return blob, nil
@@ -780,6 +780,38 @@ func TestRender_FilePreview(t *testing.T) {
 			},
 		)
 	})
+	t.Run("single-line", func(t *testing.T) {
+		testRender(
+			util.URLJoin(markup.TestRepoURL, "src", "commit", "4c1aaf56bcb9f39dcf65f3f250726850aed13cd6", "single-line.txt")+"#L1",
+			`<p></p>`+
+				`<div class="file-preview-box">`+
+				`<div class="header">`+
+				`<div>`+
+				`<a href="http://localhost:3000/gogits/gogs/" rel="nofollow">gogits/gogs</a> – `+
+				`<a href="http://localhost:3000/gogits/gogs/src/commit/4c1aaf56bcb9f39dcf65f3f250726850aed13cd6/single-line.txt#L1" class="muted" rel="nofollow">single-line.txt</a>`+
+				`</div>`+
+				`<span class="text small grey">`+
+				`Line 1 in <a href="http://localhost:3000/gogits/gogs/src/commit/4c1aaf56bcb9f39dcf65f3f250726850aed13cd6" class="text black" rel="nofollow">gogits/gogs@4c1aaf5</a>`+
+				`</span>`+
+				`</div>`+
+				`<div class="ui table">`+
+				`<table class="file-preview">`+
+				`<tbody>`+
+				`<tr>`+
+				`<td class="lines-num"><span data-line-number="1"></span></td>`+
+				`<td class="lines-code chroma"><code class="code-inner">A`+`</code></td>`+
+				`</tr>`+
+				`</tbody>`+
+				`</table>`+
+				`</div>`+
+				`</div>`+
+				`<p></p>`,
+			map[string]string{
+				"user": "gogits",
+				"repo": "gogs2",
+			},
+		)
+	})
 
 	t.Run("AppSubURL", func(t *testing.T) {
 		urlWithSub := util.URLJoin(markup.TestAppURL, "sub", markup.TestOrgRepo, "src", "commit", sha, "path", "to", "file.go") + "#L2-L3"

modules/markup/tests/repo/repo1_filepreview/refs/heads/master

@@ -1 +1 @@
-190d9492934af498c3f669d6a2431dc5459e5b20
+4c1aaf56bcb9f39dcf65f3f250726850aed13cd6