Unreachable reached

[Keats]

From getzola/zola#558

thread 'thread 'thread '<unnamed><unnamed><unnamed>' panicked at '' panicked at 'internal error: entered unreachable code: render_node -> unexpected node: Extends(WS { left: false, right: false }, "layout.html")internal error: entered unreachable code: render_node -> unexpected node: Extends(WS { left: false, right: false }, "layout.html")', ' panicked at '/cargo/registry/src/github.com-1ecc6299db9ec823/tera-0.11.20/src/renderer/processor.rs', :internal error: entered unreachable code: render_node -> unexpected node: Extends(WS { left: false, right: false }, "layout.html")/cargo/registry/src/github.com-1ecc6299db9ec823/tera-0.11.20/src/renderer/processor.rs774', :/cargo/registry/src/github.com-1ecc6299db9ec823/tera-0.11.20/src/renderer/processor.rs:77418::

[Keats]

So it is trying to render an extends tag, not sure how we ever get there...

@focusaurus

Do you have any memories on the kind of templates that was causing the issue? The parser should not allow extends in a place where it would get rendered and I can't write a template reproducing it.
The easy solution is to remove the unreachable! here but that means we let through bugs.

[focusaurus]

Oh interesting, yes that makes sense. I am converting a site that uses pug templates and pug templates have an extends keyword. Let me futz around a bit and see if I can reproduce it now that I know what the code was trying to do.

[Keats]

@focusaurus did you manage to reproduce it?

[focusaurus]

Presumably it was something related to {% extends "layout.html" %} which I do use in my templates, but I can't reproduce it.

[Keats]

Yes, definitely related to an extends like that. The issue is that the parser probably allows it at a place it shouldn't be allowed.

[sbstp]

I'm getting an issue similar to this

{% macro path_item(path) %}
    <span class="path" title="{{ path.path }}">{{ path.filename }}</span>
{% endmacro path_item %}

...

<td>{{ self::path_item(path=match.info.path) }}</td>

thread 'main' panicked at 'internal error: entered unreachable code: render_node -> unexpected node: MacroDefinition(WS { left: false, right: false }, MacroDefinition { name: "path_item", args: {"path": None}, body: [Text("\n        <span class=\"path\" title=\""), VariableBlock(Expr { val: Ident("path.path"), negated: false, filters: [] }), Text("\">"), VariableBlock(Expr { val: Ident("path.filename"), negated: false, filters: [] }), Text("</span>\n    ")] }, WS { left: false, right: false })', /home/simon/.cargo/registry/src/github.com-1ecc6299db9ec823/tera-0.11.20/src/renderer/processor.rs:774:18```

[sbstp]

Ah sorry to have bothered you. I believe the issue is in this little sentence: "Macros currently need to be defined in a separate file and imported to be useable."

[Keats]

that's still a panic that should be fixed! Thanks for the report

[Keats]

I added a failing test for that @sbstp on the v1 branch.
Fixing it at the rendering phase is easy but I need to think whether we can error on that at parsing time instead which would be nicer.

[sbstp]

Are macros limited to being in a standalone file because of some technical reason?

[Keats]

I don't remember exactly, I think that the issue with being in the same file is that the file was usually to be rendered so the macro could have been defined in a forloop or something similar and it currently only checks the top level of a template for macro definitions. It could be allowed by searching recursively in the AST but now I kind of like macros being separated from actual templates.

[focusaurus]

Thank you for the fix! 👍