trace_nu_plugin

This is a diagnostic wrapper for Nu plugins which dumps the raw plugin stdin and stdout into files in the user's home directory.

This is probably only useful for people writing plugins in languages other than Rust.

Requires the new plugin API of Nu >= 0.93

Usage

Add the plugin using the tracer as a shell interpreter, using the full paths of the plugin tracer and the actual plugin.

> plugin add -s ~/vc/sjg/dev.rust/trace_nu_plugin/target/debug/trace_nu_plugin ~/vc/tesujimath/nu_plugin_bash_env/nu_plugin_bash_env
> plugin use bash_env

The output appears in files named after the plugin, in the user's home directory.

WARNING: trace output will accumulate for as long as the plugin is installed with the trace wrapper. Large files are possible. Be sure to remove the plugin with plugin rm when finished tracing, and reinstall without the trace wrapper.

Then:

> cd ~/junk

> echo "export A=123" | bash-env
╭───┬─────╮
│ A │ 123 │
╰───┴─────╯

> cat ~/vc/tesujimath/nu_plugin_bash_env/nu_plugin_bash_env.in.raw
{"Hello":{"protocol":"nu-plugin","version":"0.92.3","features":[{"name":"LocalSocket"}]}}
{"Call":[0,"Signature"]}
"Goodbye"
{"Hello":{"protocol":"nu-plugin","version":"0.92.3","features":[{"name":"LocalSocket"}]}}
{"Call":[0,{"Run":{"name":"bash-env","call":{"head":{"start":131720,"end":131728},"positional":[],"named":[]},"input":{"Value":{"String":{"val":"export A=123","span":{"start":131703,"end":131717}}}}}}]}
"Goodbye"

> cat ~/vc/tesujimath/nu_plugin_bash_env/nu_plugin_bash_env.out.raw
json{"Hello":{"protocol":"nu-plugin","version":"0.92.0","features":[]}}
{"CallResponse":[0,{"Signature":[{"sig":{"name":"bash-env","usage":"get environment variables from Bash format file and/or stdin","extra_usage":"","search_terms":[],"required_positional":[],"optional_positional":[{"name":"path","desc":"path to environment file","shape":"String","var_id":null,"default_value":null}],"rest_positional":null,"named":[{"long":"help","short":"h","arg":null,"required":false,"desc":"Display the help message for this command","var_id":null,"default_value":null}],"input_output_types":[["Nothing","Any"],["String","Any"]],"allow_variants_without_examples":true,"is_filter":true,"creates_scope":false,"allows_unknown_args":false,"category":"Env"},"examples":[]}]}]}
json{"Hello":{"protocol":"nu-plugin","version":"0.92.0","features":[]}}
{"CallResponse":[0,{"PipelineData":{"Value":{"Record":{"val":{"A":{"String":{"val":"123","span":{"start":0,"end":0}}}},"span":{"start":0,"end":0}}}}}]}

Note that there is an invisible \004 character before each occurence of the string json.

> od -c nu_plugin_bash_env.out.raw | head -1
0000000 004   j   s   o   n   {   "   H   e   l   l   o   "   :   {   "
```