From 9957bb361dac0f1edcadf3753bef13f543d57228 Mon Sep 17 00:00:00 2001
From: Jonas Marcello <jonas.marcello@esbme.com>
Date: Fri, 24 Feb 2023 21:09:16 +0100
Subject: [PATCH] Add const generics to doctest names for structt

---
 crates/hir/src/lib.rs       |  35 +++++++++++-
 crates/ide/src/runnables.rs | 108 ++++++++++++++++++++++++++++++++++++
 2 files changed, 141 insertions(+), 2 deletions(-)

diff --git a/crates/hir/src/lib.rs b/crates/hir/src/lib.rs
index 883838293e..369f9192d1 100644
--- a/crates/hir/src/lib.rs
+++ b/crates/hir/src/lib.rs
@@ -42,7 +42,7 @@ use hir_def::{
     adt::VariantData,
     body::{BodyDiagnostic, SyntheticSyntax},
     expr::{BindingAnnotation, ExprOrPatId, LabelId, Pat, PatId},
-    generics::{LifetimeParamData, TypeOrConstParamData, TypeParamProvenance},
+    generics::{ConstParamData, LifetimeParamData, TypeOrConstParamData, TypeParamProvenance},
     item_tree::ItemTreeNode,
     lang_item::{LangItem, LangItemTarget},
     layout::{Layout, LayoutError, ReprOptions},
@@ -1189,6 +1189,31 @@ impl Adt {
             .map(|arena| arena.1.clone())
     }
 
+    /// Returns an iterator of all `const` generic paramaters
+    ///
+    /// This method is not well optimized, I could not statisfy the borrow
+    /// checker. I'm sure there are smarter ways to return the consts names
+    pub fn consts(&self, db: &dyn HirDatabase) -> impl Iterator<Item = ConstParamData> {
+        let resolver = match self {
+            Adt::Struct(s) => s.id.resolver(db.upcast()),
+            Adt::Union(u) => u.id.resolver(db.upcast()),
+            Adt::Enum(e) => e.id.resolver(db.upcast()),
+        };
+        resolver
+            .generic_params()
+            .map_or(vec![], |gp| {
+                gp.as_ref()
+                    .type_or_consts
+                    .iter()
+                    .filter_map(|arena| match arena.1 {
+                        TypeOrConstParamData::ConstParamData(consts) => Some(consts.clone()),
+                        _ => None,
+                    })
+                    .collect::<Vec<ConstParamData>>()
+            })
+            .into_iter()
+    }
+
     pub fn as_enum(&self) -> Option<Enum> {
         if let Self::Enum(v) = self {
             Some(*v)
@@ -3358,15 +3383,21 @@ impl Type {
             .map(move |ty| self.derived(ty))
     }
 
-    /// Combines lifetime indicators and type arguments into a single `Iterator`
+    /// Combines lifetime indicators, type and constant parameters into a single `Iterator`
     pub fn lifetime_and_type_arguments<'a>(
         &'a self,
         db: &'a dyn HirDatabase,
     ) -> impl Iterator<Item = SmolStr> + 'a {
+        // iterate the lifetime
         self.as_adt()
             .and_then(|a| a.lifetime(db).and_then(|lt| Some((&lt.name).to_smol_str())))
             .into_iter()
+            // add the type paramaters
             .chain(self.type_arguments().map(|ty| SmolStr::new(ty.display(db).to_string())))
+            // add const paramameters
+            .chain(self.as_adt().map_or(vec![], |a| {
+                a.consts(db).map(|cs| cs.name.to_smol_str()).collect::<Vec<SmolStr>>()
+            }))
     }
 
     pub fn iterate_method_candidates_with_traits<T>(
diff --git a/crates/ide/src/runnables.rs b/crates/ide/src/runnables.rs
index b0477e9678..7af969c5d0 100644
--- a/crates/ide/src/runnables.rs
+++ b/crates/ide/src/runnables.rs
@@ -1102,6 +1102,114 @@ impl<T, U> Data<'a, T, U> {
             "#]],
         );
     }
+
+    #[test]
+    fn test_runnables_doc_test_in_impl_with_const() {
+        check(
+            r#"
+//- /lib.rs
+$0
+fn main() {}
+
+struct Data<const N: usize>;
+impl<const N: usize> Data<N> {
+    /// ```
+    /// let x = 5;
+    /// ```
+    fn foo() {}
+}
+"#,
+            &[Bin, DocTest],
+            expect![[r#"
+                [
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 1..13,
+                            focus_range: 4..8,
+                            name: "main",
+                            kind: Function,
+                        },
+                        kind: Bin,
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 79..133,
+                            name: "foo",
+                        },
+                        kind: DocTest {
+                            test_id: Path(
+                                "Data<N>::foo",
+                            ),
+                        },
+                        cfg: None,
+                    },
+                ]
+            "#]],
+        );
+    }
+
+    #[test]
+    fn test_runnables_doc_test_in_impl_with_lifetime_types_and_const() {
+        check(
+            r#"
+//- /lib.rs
+$0
+fn main() {}
+
+struct Data<'a, T, const N: usize>;
+impl<'a, T, const N: usize> Data<'a, T, N> {
+    /// ```
+    /// let x = 5;
+    /// ```
+    fn foo() {}
+}
+"#,
+            &[Bin, DocTest],
+            expect![[r#"
+                [
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 1..13,
+                            focus_range: 4..8,
+                            name: "main",
+                            kind: Function,
+                        },
+                        kind: Bin,
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 100..154,
+                            name: "foo",
+                        },
+                        kind: DocTest {
+                            test_id: Path(
+                                "Data<'a,T,N>::foo",
+                            ),
+                        },
+                        cfg: None,
+                    },
+                ]
+            "#]],
+        );
+    }
     #[test]
     fn test_runnables_module() {
         check(