Manifesting YAML silently ignores errors in unevaluated imported objects

[ThePletch]

When calling std.manifestYamlDoc(thing), for values that:

• are imported from another file
• are set to a key of the object being serialized to YAML
• would produce an error when evaluated
• are not evaluated at another point during execution of the Jsonnet code,

the error is swallowed and an empty value is rendered in the resulting YAML.

Minimal reproduction:

// imported.libsonnet
{
  key:
    assert false : "it broke";
    "somestring",
}

// main.jsonnet
local busted = import 'imported.libsonnet';

std.manifestYamlDoc({key: busted})

Outputs:

"key":
  

If the value is evaluated by another operation during execution, e.g.:

// main.jsonnet
local busted = import 'imported.libsonnet';

std.manifestYamlDoc(std.trace(std.manifestJson({key: busted}), {key: busted}))

the error is raised as expected.