renderTree

pub fn renderTree(gpa: Allocator, w: *Writer, tree: Ast, fixups: Fixups) Error!void {
    assert(tree.errors.len == 0); // Cannot render an invalid tree.
    var auto_indenting_stream: AutoIndentingStream = .init(gpa, w, indent_delta);
    defer auto_indenting_stream.deinit();
    var r: Render = .{
        .gpa = gpa,
        .ais = &auto_indenting_stream,
        .tree = tree,
        .fixups = fixups,
    };

    // Render all the line comments at the beginning of the file.
    const comment_end_loc = tree.tokenStart(0);
    _ = try renderComments(&r, 0, comment_end_loc);

    if (tree.tokenTag(0) == .container_doc_comment) {
        try renderContainerDocComments(&r, 0);
    }

    switch (tree.mode) {
        .zig => try renderMembers(&r, tree.rootDecls()),
        .zon => {
            try renderExpression(
                &r,
                tree.rootDecls()[0],
                .newline,
            );
        },
    }

    if (auto_indenting_stream.disabled_offset) |disabled_offset| {
        try writeFixingWhitespace(auto_indenting_stream.underlying_writer, tree.source[disabled_offset..]);
    }
}