{% if trace.function %}
    at
    <strong>
        <abbr title="{{ trace.class }}">{{ trace.short_class }}</abbr>
        {{ trace.type ~ trace.function }}
    </strong>
    ({{ trace.args|format_args }})
    <br />
{% endif %}

{% if trace.file is defined and trace.line is defined %}
    in {{ trace.file|format_file(trace.line) }}&nbsp;
    {% spaceless %}
    <a href="#" onclick="toggle('trace_{{ prefix ~ '_' ~ i }}'); switchIcons('icon_{{ prefix ~ '_' ~ i }}_open', 'icon_{{ prefix ~ '_' ~ i }}_close'); return false;">
        <img class="toggle" id="icon_{{ prefix ~ '_' ~ i }}_close" alt="-" src="{{ asset('bundles/framework/images/blue_picto_less.gif') }}" style="visibility: {{ 0 == i ? 'display' : 'hidden' }}" />
        <img class="toggle" id="icon_{{ prefix ~ '_' ~ i }}_open" alt="+" src="{{ asset('bundles/framework/images/blue_picto_more.gif') }}" style="visibility: {{ 0 == i ? 'hidden' : 'display' }}; margin-left: -18px" />
    </a>
    {% endspaceless %}
    <div id="trace_{{ prefix ~ '_' ~ i }}" style="display: {{ 0 == i ? 'block' : 'none' }}" class="trace">
        {{ trace.file|file_excerpt(trace.line) }}
    </div>
{% endif %}

{% if trace.function %}
    at
    <strong>
        <abbr title="{{ trace.class }}">{{ trace.short_class }}</abbr>
        {{ trace.type ~ trace.function }}
    </strong>
    ({{ trace.args|format_args }})
{% endif %}

{% if trace.file is defined and trace.file and trace.line is defined and trace.line %}
    {{ trace.function ? '<br />' : '' }}
    in {{ trace.file|format_file(trace.line) }}&nbsp;
    {% spaceless %}
    <a href="#" onclick="toggle('trace_{{ prefix ~ '_' ~ i }}'); switchIcons('icon_{{ prefix ~ '_' ~ i }}_open', 'icon_{{ prefix ~ '_' ~ i }}_close'); return false;">
        <img class="toggle" id="icon_{{ prefix ~ '_' ~ i }}_close" alt="-" src="{{ asset('bundles/framework/images/blue_picto_less.gif') }}" style="visibility: {{ 0 == i ? 'display' : 'hidden' }}" />
        <img class="toggle" id="icon_{{ prefix ~ '_' ~ i }}_open" alt="+" src="{{ asset('bundles/framework/images/blue_picto_more.gif') }}" style="visibility: {{ 0 == i ? 'hidden' : 'display' }}; margin-left: -18px" />
    </a>
    {% endspaceless %}
    <div id="trace_{{ prefix ~ '_' ~ i }}" style="display: {{ 0 == i ? 'block' : 'none' }}" class="trace">
        {{ trace.file|file_excerpt(trace.line) }}
    </div>
{% endif %}

Fix trace to not show 'in at line' when file/line are empty.
[TwigBundle] Fix trace to not show 'in at line' when file/line are empty.

