[UI] Adjust trailing EOL behavior for empty file

- Follow up #4835
- Currently for empty files (file size is shown in the file header) the
"No EOL" information is being shown, even though it doesn't really
make sense to show that for empty files.
- Add integration test.
- Ref: https://codeberg.org/Codeberg/Community/issues/1612#issuecomment-2169437

(cherry picked from commit e9a89a188e)

routers/web/repo/view.go

@@ -560,15 +560,16 @@ func renderFile(ctx *context.Context, entry *git.TreeEntry) {
 			//   empty: 0 lines; "a": 1 line; "a\n": 1 line; "a\nb": 2 lines;
 			//   When rendering, the last empty line is not rendered in U and isn't counted towards the number of lines.
 			//   To tell users that the file not contains a trailing EOL, text with a tooltip is displayed in the file header.
+			//   Trailing EOL is only considered if the file has content.
 			// This NumLines is only used for the display on the UI: "xxx lines"
-			hasTrailingEOL := bytes.HasSuffix(buf, []byte{'\n'})
-			ctx.Data["HasTrailingEOL"] = hasTrailingEOL
-			ctx.Data["HasTrailingEOLSet"] = true
 			if len(buf) == 0 {
 				ctx.Data["NumLines"] = 0
 			} else {
+				hasNoTrailingEOL := !bytes.HasSuffix(buf, []byte{'\n'})
+				ctx.Data["HasNoTrailingEOL"] = hasNoTrailingEOL
+
 				numLines := bytes.Count(buf, []byte{'\n'})
-				if !hasTrailingEOL {
+				if hasNoTrailingEOL {
 					numLines++
 				}
 				ctx.Data["NumLines"] = numLines

templates/repo/file_info.tmpl

@@ -9,7 +9,7 @@
 			{{.NumLines}} {{ctx.Locale.TrN .NumLines "repo.line" "repo.lines"}}
 		</div>
 	{{end}}
-	{{if and .HasTrailingEOLSet (not .HasTrailingEOL)}}
+	{{if .HasNoTrailingEOL}}
 		<div class="file-info-entry" data-tooltip-content="{{ctx.Locale.Tr "repo.no_eol.tooltip"}}">
 			{{ctx.Locale.Tr "repo.no_eol.text"}}
 		</div>

tests/integration/repo_view_test.go

@@ -179,43 +179,47 @@ func TestRepoViewFileLines(t *testing.T) {
 				TreePath:      "test-4",
 				ContentReader: strings.NewReader("Really two\nlines\n"),
 			},
+			{
+				Operation:     "create",
+				TreePath:      "empty",
+				ContentReader: strings.NewReader(""),
+			},
+			{
+				Operation:     "create",
+				TreePath:      "seemingly-empty",
+				ContentReader: strings.NewReader("\n"),
+			},
 		})
 		defer f()
 
-		t.Run("No EOL", func(t *testing.T) {
-			defer tests.PrintCurrentTest(t)()
-
-			req := NewRequest(t, "GET", repo.Link()+"/src/branch/main/test-1")
+		testEOL := func(t *testing.T, filename string, hasEOL bool) {
+			t.Helper()
+			req := NewRequestf(t, "GET", "%s/src/branch/main/%s", repo.Link(), filename)
 			resp := MakeRequest(t, req, http.StatusOK)
 			htmlDoc := NewHTMLParser(t, resp.Body)
 
 			fileInfo := htmlDoc.Find(".file-info").Text()
-			assert.Contains(t, fileInfo, "No EOL")
+			if hasEOL {
+				assert.NotContains(t, fileInfo, "No EOL")
+			} else {
+				assert.Contains(t, fileInfo, "No EOL")
+			}
+		}
 
-			req = NewRequest(t, "GET", repo.Link()+"/src/branch/main/test-3")
-			resp = MakeRequest(t, req, http.StatusOK)
-			htmlDoc = NewHTMLParser(t, resp.Body)
+		t.Run("No EOL", func(t *testing.T) {
+			defer tests.PrintCurrentTest(t)()
 
-			fileInfo = htmlDoc.Find(".file-info").Text()
-			assert.Contains(t, fileInfo, "No EOL")
+			testEOL(t, "test-1", false)
+			testEOL(t, "test-3", false)
 		})
 
 		t.Run("With EOL", func(t *testing.T) {
 			defer tests.PrintCurrentTest(t)()
 
-			req := NewRequest(t, "GET", repo.Link()+"/src/branch/main/test-2")
-			resp := MakeRequest(t, req, http.StatusOK)
-			htmlDoc := NewHTMLParser(t, resp.Body)
-
-			fileInfo := htmlDoc.Find(".file-info").Text()
-			assert.NotContains(t, fileInfo, "No EOL")
-
-			req = NewRequest(t, "GET", repo.Link()+"/src/branch/main/test-4")
-			resp = MakeRequest(t, req, http.StatusOK)
-			htmlDoc = NewHTMLParser(t, resp.Body)
-
-			fileInfo = htmlDoc.Find(".file-info").Text()
-			assert.NotContains(t, fileInfo, "No EOL")
+			testEOL(t, "test-2", true)
+			testEOL(t, "test-4", true)
+			testEOL(t, "empty", true)
+			testEOL(t, "seemingly-empty", true)
 		})
 	})
 }