topdown/eval: fix 'every' term plugging on save #4775
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ast/compile_test.go
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| every y in [2] { | ||
| y in output | ||
| } | ||
| }`), |
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☝️ I think we should be able to reorder this properly: If comp = [ 1 | true ] is would come after object.get(...), we'd be fine.
Right now, when checking the output vars of the call, we get nothing because the call is unsafe. However, we also fly through the checks required to add the object.get call to the reordered body, so we'd be getting the same ordering back. However, with the every call, we'll get an error: output is unsafe, because it's never removed from the unsafe set, since it's never part of the output vars of the reordered body.
Previously missing plugging could cause unsafe variables in the PE output. Now, all terms in the 'every' body should be plugged properly. The approach taken here is to plug them all, and then fix the key and val var names of the copied every expression. Those vars are fresh after the compiler is done with the expression, so plugging them should never have any effect outside of the rename. Signed-off-by: Stephan Renatus <stephan.renatus@gmail.com>
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| for i := range every.Body { | ||
| switch t := every.Body[i].Terms.(type) { | ||
| case *ast.Term: | ||
| every.Body[i].Terms = e.e.bindings.Plug(t) | ||
| every.Body[i].Terms = e.e.bindings.PlugNamespaced(t, e.e.caller.bindings) | ||
| case []*ast.Term: | ||
| for j := range t { | ||
| t[j] = e.e.bindings.Plug(t[j]) | ||
| for j := 1; j < len(t); j++ { // don't plug operator, t[0] | ||
| t[j] = e.e.bindings.PlugNamespaced(t[j], e.e.caller.bindings) | ||
| } | ||
| } | ||
| } |
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Unrelated to these changes, but it looks like we're only dealing with single terms and calls here. What happens if the body contains an ast.Every? Is there some rewriting that I'm not aware of?
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Good find. Probably an oversight. I'll look into it later.
Previously missing plugging could cause unsafe variables in the
PE output.
Now, all terms in the 'every' body should be plugged properly.
The approach taken here is to plug them all, and then fix the
key and val var names of the copied every expression. Those vars
are fresh after the compiler is done with the expression, so
plugging them should never have any effect outside of the rename.
Fixes the first part of #4766