Function format_text_diff_limits_context

src/render.rs:884–908

()

    #[test]
    fn format_text_diff_limits_context() {
        // With context_lines=1, only 1 context line should surround a change.
        let renderer = Renderer::new(RenderOptions {
            color_mode: ColorMode::Never,
            context_lines: 1,
            ..Default::default()
        });
        let old = b"a\nb\nc\nd\ne\n";
        let new = b"a\nb\nNEW\nc\nd\ne\n";

        let mut out = Vec::new();
        renderer.format_text_diff(&mut out, old, new, 0);
        let out = String::from_utf8(out).unwrap();

        // Leading: only "b" (1 line before change), then NEW, then only "c"
        assert!(!out.contains("  a\n"), "leading context not limited: {out}");
        assert!(out.contains("  b\n"));
        assert!(out.contains("+ NEW\n"));
        assert!(out.contains("  c\n"));
        assert!(
            !out.contains("  d\n"),
            "trailing context not limited: {out}"
        );
        assert!(!out.contains("  e\n"));
    }

    #[test]
    fn inline_highlight_marks_changed_words() {