displaythis-impl 1.0.23

use crate::ast::{Enum, Field, Input, Struct, Variant};
use syn::{Error, Result};

impl Input<'_> {
    pub(crate) fn validate(&self) -> Result<()> {
        match self {
            Input::Struct(input) => input.validate(),
            Input::Enum(input) => input.validate(),
        }
    }
}

impl Struct<'_> {
    fn validate(&self) -> Result<()> {
        for field in &self.fields {
            field.validate()?;
        }
        Ok(())
    }
}

impl Enum<'_> {
    fn validate(&self) -> Result<()> {
        let has_display = self.has_display();
        for variant in &self.variants {
            variant.validate()?;
            if has_display && variant.attrs.display.is_none() {
                return Err(Error::new_spanned(
                    variant.original,
                    "missing #[display(\"...\")] display attribute",
                ));
            }
        }
        Ok(())
    }
}

impl Variant<'_> {
    fn validate(&self) -> Result<()> {
        for field in &self.fields {
            field.validate()?;
        }
        Ok(())
    }
}

impl Field<'_> {
    fn validate(&self) -> Result<()> {
        if let Some(display) = &self.attrs.display {
            return Err(Error::new_spanned(
                display.original,
                "not expected here; the #[display(...)] attribute belongs on top of a struct or an enum variant",
            ));
        }
        Ok(())
    }
}