trustfall_rustdoc_adapter/adapter/

mod.rs

use std::sync::{Arc, LazyLock};

use rustdoc_types::Item;
use trustfall::{
    FieldValue, Schema,
    provider::{
        Adapter, AsVertex, ContextIterator, ContextOutcomeIterator, EdgeParameters,
        ResolveEdgeInfo, ResolveInfo, Typename, VertexIterator, resolve_coercion_with,
    },
};

use crate::PackageIndex;

use self::{
    origin::Origin,
    vertex::{Vertex, VertexKind},
};

mod edges;
mod enum_variant;
mod optimizations;
mod origin;
mod properties;
mod receiver;
mod rust_type_name;
mod vertex;

#[cfg(test)]
mod tests;

static SCHEMA: LazyLock<Schema> = LazyLock::new(|| {
    Schema::parse(include_str!("../rustdoc_schema.graphql")).expect("schema not valid")
});

#[non_exhaustive]
pub struct RustdocAdapter<'a> {
    current_crate: &'a PackageIndex<'a>,
    previous_crate: Option<&'a PackageIndex<'a>>,
}

impl<'a> RustdocAdapter<'a> {
    pub fn new(
        current_crate: &'a PackageIndex<'a>,
        previous_crate: Option<&'a PackageIndex<'a>>,
    ) -> Self {
        Self {
            current_crate,
            previous_crate,
        }
    }

    pub fn schema() -> &'static Schema {
        &SCHEMA
    }

    /// Returns the crate at the given origin.
    ///
    /// Panics if `Origin::PreviousCrate` is passed and there is no previous crate.
    #[inline]
    pub(crate) fn crate_at_origin(&self, origin: Origin) -> &'a PackageIndex<'a> {
        match origin {
            Origin::CurrentCrate => self.current_crate,
            Origin::PreviousCrate => self
                .previous_crate
                .expect("previous crate was not provided"),
        }
    }
}

impl Drop for RustdocAdapter<'_> {
    fn drop(&mut self) {}
}

impl<'a> Adapter<'a> for &'a RustdocAdapter<'a> {
    type Vertex = Vertex<'a>;

    fn resolve_starting_vertices(
        &self,
        edge_name: &Arc<str>,
        _parameters: &EdgeParameters,
        _resolve_info: &ResolveInfo,
    ) -> VertexIterator<'a, Self::Vertex> {
        match edge_name.as_ref() {
            "Crate" => Box::new(std::iter::once(Vertex::new_crate(
                Origin::CurrentCrate,
                self.current_crate,
            ))),
            "CrateDiff" => {
                let previous_crate = self.previous_crate.expect("no previous crate provided");
                Box::new(std::iter::once(Vertex {
                    origin: Origin::CurrentCrate,
                    kind: VertexKind::CrateDiff((self.current_crate, previous_crate)),
                }))
            }
            _ => unreachable!("resolve_starting_vertices {edge_name}"),
        }
    }

    fn resolve_property<V: AsVertex<Self::Vertex> + 'a>(
        &self,
        contexts: ContextIterator<'a, V>,
        type_name: &Arc<str>,
        property_name: &Arc<str>,
        _resolve_info: &ResolveInfo,
    ) -> ContextOutcomeIterator<'a, V, FieldValue> {
        if property_name.as_ref() == "__typename" {
            Box::new(contexts.map(|ctx| match ctx.active_vertex() {
                Some(vertex) => {
                    let value = vertex.typename().into();
                    (ctx, value)
                }
                None => (ctx, FieldValue::Null),
            }))
        } else {
            match type_name.as_ref() {
                "Crate" => properties::resolve_crate_property(contexts, property_name),
                "Item" | "GenericItem" => {
                    properties::resolve_item_property(contexts, property_name)
                }
                "ImplOwner"
                | "Struct"
                | "StructField"
                | "Enum"
                | "Variant"
                | "PlainVariant"
                | "TupleVariant"
                | "StructVariant"
                | "Union"
                | "Trait"
                | "ExportableFunction"
                | "Function"
                | "Method"
                | "Impl"
                | "GlobalValue"
                | "Constant"
                | "Static"
                | "AssociatedType"
                | "AssociatedConstant"
                | "Module"
                | "Macro"
                | "ProcMacro"
                | "FunctionLikeProcMacro"
                | "AttributeProcMacro"
                | "DeriveProcMacro"
                    if matches!(
                        property_name.as_ref(),
                        "id" | "crate_id"
                            | "name"
                            | "docs"
                            | "attrs"
                            | "doc_hidden"
                            | "deprecated"
                            | "public_api_eligible"
                            | "visibility_limit"
                    ) =>
                {
                    // properties inherited from Item, accesssed on Item subtypes
                    properties::resolve_item_property(contexts, property_name)
                }
                "Module" => properties::resolve_module_property(contexts, property_name),
                "Struct" => properties::resolve_struct_property(contexts, property_name),
                "StructField" => properties::resolve_struct_field_property(contexts, property_name),
                "Enum" => properties::resolve_enum_property(contexts, property_name),
                "Variant" | "PlainVariant" | "TupleVariant" | "StructVariant" => {
                    properties::resolve_enum_variant_property(contexts, property_name)
                }
                "Union" => properties::resolve_union_property(contexts, property_name),
                "Span" => properties::resolve_span_property(contexts, property_name),
                "Path" => properties::resolve_path_property(contexts, property_name),
                "ImportablePath" => {
                    properties::resolve_importable_path_property(contexts, property_name)
                }
                "FunctionLike" | "ExportableFunction" | "Function" | "Method"
                    if matches!(
                        property_name.as_ref(),
                        "const" | "unsafe" | "async" | "has_body" | "signature"
                    ) =>
                {
                    properties::resolve_function_like_property(contexts, property_name)
                }
                "ExportableFunction" | "Function" | "Method"
                    if matches!(property_name.as_ref(), "export_name") =>
                {
                    properties::resolve_exportable_function_property(contexts, property_name)
                }
                "Function" => properties::resolve_function_property(contexts, property_name),
                "FunctionParameter" => {
                    properties::resolve_function_parameter_property(contexts, property_name)
                }
                "ReturnValue" => properties::resolve_return_value_property(contexts, property_name),
                "FunctionAbi" => properties::resolve_function_abi_property(contexts, property_name),
                "Impl" => properties::resolve_impl_property(contexts, property_name),
                "Attribute" => properties::resolve_attribute_property(contexts, property_name),
                "AttributeMetaItem" => {
                    properties::resolve_attribute_meta_item_property(contexts, property_name)
                }
                "Trait" => properties::resolve_trait_property(contexts, property_name, self),
                "ImplementedTrait" => {
                    properties::resolve_implemented_trait_property(contexts, property_name, self)
                }
                "Static" => properties::resolve_static_property(contexts, property_name),
                "RawType" | "ResolvedPathType" if matches!(property_name.as_ref(), "name") => {
                    // fields from "RawType"
                    properties::resolve_raw_type_property(contexts, property_name)
                }
                "AssociatedType" => {
                    properties::resolve_associated_type_property(contexts, property_name)
                }
                "AssociatedConstant" => {
                    properties::resolve_associated_constant_property(contexts, property_name)
                }
                "Constant" => properties::resolve_constant_property(contexts, property_name),
                "Discriminant" => {
                    properties::resolve_discriminant_property(contexts, property_name)
                }
                "Feature" => properties::resolve_feature_property(contexts, property_name),
                "DeriveMacroHelperAttribute" => {
                    properties::resolve_derive_macro_helper_attribute_property(
                        contexts,
                        property_name,
                    )
                }
                "GenericParameter"
                | "GenericTypeParameter"
                | "GenericLifetimeParameter"
                | "GenericConstParameter"
                    if matches!(property_name.as_ref(), "name" | "position") =>
                {
                    properties::resolve_generic_parameter_property(contexts, property_name)
                }
                "GenericTypeParameter" => properties::resolve_generic_type_parameter_property(
                    contexts,
                    property_name,
                    self,
                ),
                "GenericConstParameter" => {
                    properties::resolve_generic_const_parameter_property(contexts, property_name)
                }
                "Receiver" => properties::resolve_receiver_property(contexts, property_name),
                "RequiredTargetFeature" => {
                    properties::resolve_required_target_feature_property(contexts, property_name)
                }
                _ => unreachable!("resolve_property {type_name} {property_name}"),
            }
        }
    }

    fn resolve_neighbors<V: AsVertex<Self::Vertex> + 'a>(
        &self,
        contexts: ContextIterator<'a, V>,
        type_name: &Arc<str>,
        edge_name: &Arc<str>,
        parameters: &EdgeParameters,
        resolve_info: &ResolveEdgeInfo,
    ) -> ContextOutcomeIterator<'a, V, VertexIterator<'a, Self::Vertex>> {
        match type_name.as_ref() {
            "CrateDiff" => edges::resolve_crate_diff_edge(contexts, edge_name),
            "Crate" => edges::resolve_crate_edge(self, contexts, edge_name, resolve_info),
            "Importable"
            | "ImplOwner"
            | "Struct"
            | "Enum"
            | "Union"
            | "Trait"
            | "Function"
            | "GlobalValue"
            | "Constant"
            | "Static"
            | "Module"
            | "Macro"
            | "ProcMacro"
            | "FunctionLikeProcMacro"
            | "AttributeProcMacro"
            | "DeriveProcMacro"
                if matches!(edge_name.as_ref(), "importable_path" | "canonical_path") =>
            {
                edges::resolve_importable_edge(contexts, edge_name, self)
            }
            "Item"
            | "GenericItem"
            | "ImplOwner"
            | "Struct"
            | "StructField"
            | "Enum"
            | "Variant"
            | "PlainVariant"
            | "TupleVariant"
            | "Union"
            | "StructVariant"
            | "Trait"
            | "ExportableFunction"
            | "Function"
            | "Method"
            | "Impl"
            | "GlobalValue"
            | "Constant"
            | "Static"
            | "AssociatedType"
            | "AssociatedConstant"
            | "Module"
            | "Macro"
            | "ProcMacro"
            | "FunctionLikeProcMacro"
            | "AttributeProcMacro"
            | "DeriveProcMacro"
                if matches!(edge_name.as_ref(), "span" | "attribute") =>
            {
                edges::resolve_item_edge(contexts, edge_name)
            }
            "ImplOwner" | "Struct" | "Enum" | "Union"
                if matches!(edge_name.as_ref(), "impl" | "inherent_impl") =>
            {
                edges::resolve_impl_owner_edge(self, contexts, edge_name, resolve_info)
            }
            "Function" | "Method" | "FunctionLike" | "ExportableFunction"
                if matches!(edge_name.as_ref(), "parameter" | "abi" | "return_value") =>
            {
                edges::resolve_function_like_edge(contexts, edge_name)
            }
            "GenericItem" | "ImplOwner" | "Struct" | "Enum" | "Union" | "Trait" | "Function"
            | "Method" | "Impl"
                if matches!(edge_name.as_ref(), "generic_parameter") =>
            {
                edges::resolve_generic_parameter_edge(contexts, edge_name)
            }
            "Method" if matches!(edge_name.as_ref(), "receiver") => {
                edges::resolve_receiver_edge(contexts, edge_name)
            }
            "Function" | "Method" if matches!(edge_name.as_ref(), "requires_feature") => {
                edges::resolve_requires_target_feature_edge(contexts, self)
            }
            "Module" => edges::resolve_module_edge(contexts, edge_name, self),
            "Struct" => edges::resolve_struct_edge(contexts, edge_name, self),
            "Variant" | "PlainVariant" | "TupleVariant" | "StructVariant" => {
                edges::resolve_variant_edge(contexts, edge_name, self)
            }
            "Enum" => edges::resolve_enum_edge(contexts, edge_name, self, resolve_info),
            "Union" => edges::resolve_union_edge(contexts, edge_name, self),
            "StructField" => edges::resolve_struct_field_edge(contexts, edge_name),
            "Impl" => edges::resolve_impl_edge(self, contexts, edge_name, resolve_info),
            "Trait" => edges::resolve_trait_edge(contexts, edge_name, self),
            "ImplementedTrait" => edges::resolve_implemented_trait_edge(contexts, edge_name),
            "Attribute" => edges::resolve_attribute_edge(contexts, edge_name),
            "AttributeMetaItem" => edges::resolve_attribute_meta_item_edge(contexts, edge_name),
            "Feature" => edges::resolve_feature_edge(contexts, edge_name, self),
            "DeriveProcMacro" => edges::resolve_derive_proc_macro_edge(contexts, edge_name),
            "GenericTypeParameter" => {
                edges::resolve_generic_type_parameter_edge(contexts, edge_name, self)
            }
            _ => unreachable!("resolve_neighbors {type_name} {edge_name} {parameters:?}"),
        }
    }

    fn resolve_coercion<V: AsVertex<Self::Vertex> + 'a>(
        &self,
        contexts: ContextIterator<'a, V>,
        type_name: &Arc<str>,
        coerce_to_type: &Arc<str>,
        _resolve_info: &ResolveInfo,
    ) -> ContextOutcomeIterator<'a, V, bool> {
        let coerce_to_type = coerce_to_type.clone();
        match type_name.as_ref() {
            "Item" | "GenericItem" | "Variant" | "FunctionLike" | "ExportableFunction"
            | "Importable" | "ImplOwner" | "RawType" | "GlobalValue" | "ProcMacro" => {
                resolve_coercion_with(contexts, move |vertex| {
                    let actual_type_name = vertex.typename();

                    match coerce_to_type.as_ref() {
                        "GenericItem" => matches!(
                            actual_type_name,
                            "Struct" | "Enum" | "Union" | "Trait" | "Function" | "Method"
                        ),
                        "Variant" => matches!(
                            actual_type_name,
                            "PlainVariant" | "TupleVariant" | "StructVariant"
                        ),
                        "ImplOwner" => matches!(actual_type_name, "Struct" | "Enum" | "Union"),
                        "GlobalValue" => matches!(actual_type_name, "Constant" | "Static",),
                        "ProcMacro" => matches!(
                            actual_type_name,
                            "FunctionLikeProcMacro" | "AttributeProcMacro" | "DeriveProcMacro"
                        ),
                        "ExportableFunction" => matches!(actual_type_name, "Function" | "Method"),
                        _ => {
                            // The remaining types are final (don't have any subtypes)
                            // so we can just compare the actual type name to
                            // the type we are attempting to coerce to.
                            actual_type_name == coerce_to_type.as_ref()
                        }
                    }
                })
            }
            "GenericParameter" => resolve_coercion_with(contexts, move |vertex| {
                let actual_type_name = vertex.typename();

                // The possible types are final (don't have any subtypes)
                // so we can just compare the actual type name to
                // the type we are attempting to coerce to.
                actual_type_name == coerce_to_type.as_ref()
            }),
            _ => unreachable!("resolve_coercion {type_name} {coerce_to_type}"),
        }
    }
}

pub(crate) fn supported_item_kind(item: &Item) -> bool {
    matches!(
        item.inner,
        rustdoc_types::ItemEnum::Struct(..)
            | rustdoc_types::ItemEnum::StructField(..)
            | rustdoc_types::ItemEnum::Enum(..)
            | rustdoc_types::ItemEnum::Variant(..)
            | rustdoc_types::ItemEnum::Union(..)
            | rustdoc_types::ItemEnum::Function(..)
            | rustdoc_types::ItemEnum::Impl(..)
            | rustdoc_types::ItemEnum::Trait(..)
            | rustdoc_types::ItemEnum::Constant { .. }
            | rustdoc_types::ItemEnum::Static(..)
            | rustdoc_types::ItemEnum::AssocType { .. }
            | rustdoc_types::ItemEnum::Module { .. }
            | rustdoc_types::ItemEnum::Macro { .. }
            | rustdoc_types::ItemEnum::ProcMacro { .. }
    )
}