[Bug]: Issue with plotnine + Ibis

[deepyaman]

Component

Input/Output Bindings

Severity

P3 - Low (minor inconvenience)

Shiny Version

1.4.0

Python Version

3.13.4

Minimal Reproducible Example

import narwhals as nw
import ibis
from plotnine import aes, geom_histogram, ggplot, theme_minimal
from shiny.express import input, render, ui

# Initialize the Ibis connection
con = ibis.duckdb.connect(database=':memory:')
con.create_table("penguins", ibis.examples.penguins.fetch())

ui.input_radio_buttons(
    id="species",
    label="Species",
    choices=["Adelie", "Chinstrap", "Gentoo"],
    inline=True,
)

# dat = load_penguins()
# dat = ibis.examples.penguins.fetch()
dat = con.table("penguins")
# dat = nw.from_native(con.table("penguins"))  # NARWHALS
# dat.head()

species = "Gentoo"  # Adelie, Gentoo, Chinstrap
# sel = dat.filter(nw.col("species") == species)  # NARWHALS


@render.plot
def plot():
    sel = dat.filter(dat.species == input.species())
    return (
        ggplot(aes(x="bill_length_mm"))
        + geom_histogram(dat, fill="#C2C2C4", binwidth=1)
        + geom_histogram(sel, fill="#447099", binwidth=1)
        + theme_minimal()
    )

Behavior

I get an error. The below is after manually applying a patch from #1773 to my Shiny source (to be able to actually render something).

Error Messages (if any)

(scipy-2025-shiny) deepyaman@Deepyamans-MacBook-Pro scipy-2025-shiny % shiny run app-penguin.py
Express has suppressed the object `DatabaseTable: memory.main.penguins
  species           string
  island         ...` because it is of type <class 'ibis.expr.types.relations.Table'>. Coerce to HTML, a string, or an htmltools tag to display this object.

Environment

macOS

[deepyaman]

@schloerke

[cpsievert]

What happens if you change:

con.create_table("penguins", ibis.examples.penguins.fetch())

to

_ = con.create_table("penguins", ibis.examples.penguins.fetch())

?

[schloerke]

@deepyaman , @cpsievert 's fix works!!

---

I was having trouble loading the content of the plot, similar to what you were showing me yesterday.

(Unexpected behavior)

---

Debugging the data, dat is empty... mainly my ibis.examples.penguins.fetch() is empty. 🤷 IDK why as that is verbatim copy from their website.

Changing it to the palmer penguins data, we get the expected behavior.

Code:

import ibis
from plotnine import aes, geom_histogram, ggplot, theme_minimal
from shiny.express import input, render, ui
from palmerpenguins import load_penguins

# Initialize the Ibis connection
con = ibis.duckdb.connect(database=":memory:")

penguins = load_penguins()
# penguins = ibis.examples.penguins.fetch()
_ = con.create_table("penguins", penguins)

ui.input_radio_buttons(
    id="species",
    label="Species",
    choices=["Adelie", "Chinstrap", "Gentoo"],
    inline=True,
)

dat = con.table("penguins")

# print(con.list_tables())
# print(dat)
# print(dat.as_table().count())
# print(dat.head().to_pandas())
# print(dat.to_pandas().to_dict())
# print(penguins)


@render.plot
def plot():
    sel = dat.filter(dat.species == input.species())
    return (
        ggplot(aes(x="bill_length_mm"))
        + geom_histogram(dat, fill="#C2C2C4", binwidth=1)
        + geom_histogram(sel, fill="#447099", binwidth=1)
        + theme_minimal()
    )

[deepyaman]

Debugging the data, dat is empty... mainly my ibis.examples.penguins.fetch() is empty. 🤷 IDK why as that is verbatim copy from their website.

Sorry, this looks like my mistake! Revisiting the example, I missed adding .to_pyarrow():

con.create_table("penguins", ibis.examples.penguins.fetch().to_pyarrow())

Looks like mine would have worked, but with the warning after applying from #1773; @cpsievert doing what you say (I guess you need to just not have free variables like tables in scope?) works!

Happy to close this out!