Added more unit tests

Author: M-J-Hooper

crates/ra_ide/src/inlay_hints.rs

@@ -70,6 +70,45 @@ pub(crate) fn inlay_hints(
     res
 }
 
+fn get_chaining_hints(
+    acc: &mut Vec<InlayHint>,
+    sema: &Semantics<RootDatabase>,
+    options: &InlayHintsOptions,
+    expr: ast::Expr,
+) -> Option<()> {
+    if !options.chaining_hints {
+        return None;
+    }
+
+    let ty = sema.type_of_expr(&expr)?;
+    let label = ty.display_truncated(sema.db, options.max_length).to_string();
+    if ty.is_unknown() {
+        return None;
+    }
+
+    let mut tokens = expr.syntax()
+        .siblings_with_tokens(Direction::Next)
+        .filter_map(NodeOrToken::into_token)
+        .filter(|t| match t.kind() {
+            SyntaxKind::WHITESPACE if !t.text().contains('\n') => false,
+            SyntaxKind::COMMENT => false,
+            _ => true,
+        });
+
+    // Chaining can be defined as an expression whose next sibling tokens are newline and dot
+    // Ignoring extra whitespace and comments
+    let next = tokens.next()?.kind();
+    let next_next = tokens.next()?.kind();
+    if next == SyntaxKind::WHITESPACE && next_next == SyntaxKind::DOT { 
+        acc.push(InlayHint {
+            range: expr.syntax().text_range(),
+            kind: InlayKind::ChainingHint,
+            label: label.into(),
+        });
+    }
+    Some(())
+}
+
 fn get_param_name_hints(
     acc: &mut Vec<InlayHint>,
     sema: &Semantics<RootDatabase>,
@@ -233,89 +272,13 @@ fn get_fn_signature(sema: &Semantics<RootDatabase>, expr: &ast::Expr) -> Option<
     }
 }
 
-fn get_chaining_hints(
-    acc: &mut Vec<InlayHint>,
-    sema: &Semantics<RootDatabase>,
-    options: &InlayHintsOptions,
-    expr: ast::Expr,
-) -> Option<()> {
-    if !options.chaining_hints {
-        return None;
-    }
-
-    let ty = sema.type_of_expr(&expr)?;
-    let label = ty.display_truncated(sema.db, options.max_length).to_string();
-    if ty.is_unknown() {
-        return None;
-    }
-
-    let mut tokens = expr.syntax()
-        .siblings_with_tokens(Direction::Next)
-        .filter_map(NodeOrToken::into_token)
-        .filter(|t| match t.kind() {
-            SyntaxKind::WHITESPACE if !t.text().contains('\n') => false,
-            SyntaxKind::COMMENT => false,
-            _ => true,
-        });
-
-    // Chaining can be defined as an expression whose next sibling tokens are newline and dot
-    // Ignoring extra whitespace and comments
-    let next = tokens.next()?.kind();
-    let next_next = tokens.next()?.kind();
-    if next == SyntaxKind::WHITESPACE && next_next == SyntaxKind::DOT { 
-        acc.push(InlayHint {
-            range: expr.syntax().text_range(),
-            kind: InlayKind::ChainingHint,
-            label: label.into(),
-        });
-    }
-    Some(())
-}
-
 #[cfg(test)]
 mod tests {
     use crate::inlay_hints::InlayHintsOptions;
     use insta::assert_debug_snapshot;
 
     use crate::mock_analysis::single_file;
 
-    #[test]
-    fn generic_chaining_hints() {
-        let (analysis, file_id) = single_file(
-            r#"
-            struct A<T>(T); 
-            struct B<T>(T);
-            struct C<T>(T);
-            struct X<T,R>(T, R);
-            
-            impl<T> A<T> {
-                fn new(t: T) -> Self { A(t) }
-                fn into_b(self) -> B<T> { B(self.0) }
-            }
-            impl<T> B<T> {
-                fn into_c(self) -> C<T> { C(self.0) }
-            }
-            fn test() {
-                let c = A::new(X(42, true))
-                    .into_b() // All the from A -> B -> C
-                    .into_c();
-            }"#,
-        );
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayHintsOptions{ parameter_hints: false, type_hints: false, chaining_hints: true, max_length: None}).unwrap(), @r###"
-        [
-            InlayHint {
-                range: [416; 465),
-                kind: ChainingHint,
-                label: "B<X<i32, bool>>",
-            },
-            InlayHint {
-                range: [416; 435),
-                kind: ChainingHint,
-                label: "A<X<i32, bool>>",
-            },
-        ]"###);
-    }
-
     #[test]
     fn param_hints_only() {
         let (analysis, file_id) = single_file(
@@ -1139,4 +1102,124 @@ fn main() {
         "###
         );
     }
+
+    #[test]
+    fn chaining_hints_ignore_comments() {
+        let (analysis, file_id) = single_file(
+            r#"
+            struct A(B);
+            impl A { fn into_b(self) -> B { self.0 } }
+            struct B(C)
+            impl B { fn into_c(self) -> C { self.0 } }
+            struct C;
+
+            fn main() {
+                let c = A(B(C))
+                    .into_b() // This is a comment
+                    .into_c();
+            }"#,
+        );
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayHintsOptions{ parameter_hints: false, type_hints: false, chaining_hints: true, max_length: None}).unwrap(), @r###"
+        [
+            InlayHint {
+                range: [231; 268),
+                kind: ChainingHint,
+                label: "B",
+            },
+            InlayHint {
+                range: [231; 238),
+                kind: ChainingHint,
+                label: "A",
+            },
+        ]"###);
+    }
+
+    #[test]
+    fn chaining_hints_without_newlines() {
+        let (analysis, file_id) = single_file(
+            r#"
+            struct A(B);
+            impl A { fn into_b(self) -> B { self.0 } }
+            struct B(C)
+            impl B { fn into_c(self) -> C { self.0 } }
+            struct C;
+
+            fn main() {
+                let c = A(B(C)).into_b().into_c();
+            }"#,
+        );
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayHintsOptions{ parameter_hints: false, type_hints: false, chaining_hints: true, max_length: None}).unwrap(), @r###"[]"###);
+    }
+
+    #[test]
+    fn struct_access_chaining_hints() {
+        let (analysis, file_id) = single_file(
+            r#"
+            struct A { pub b: B }
+            struct B { pub c: C }
+            struct C(pub bool);
+
+            fn main() {
+                let x = A { b: B { c: C(true) } }
+                    .b
+                    .c
+                    .0;
+            }"#,
+        );
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayHintsOptions{ parameter_hints: false, type_hints: false, chaining_hints: true, max_length: None}).unwrap(), @r###"
+        [
+            InlayHint {
+                range: [150; 221),
+                kind: ChainingHint,
+                label: "C",
+            },
+            InlayHint {
+                range: [150; 198),
+                kind: ChainingHint,
+                label: "B",
+            },
+            InlayHint {
+                range: [150; 175),
+                kind: ChainingHint,
+                label: "A",
+            },
+        ]"###);
+    }
+
+    #[test]
+    fn generic_chaining_hints() {
+        let (analysis, file_id) = single_file(
+            r#"
+            struct A<T>(T); 
+            struct B<T>(T);
+            struct C<T>(T);
+            struct X<T,R>(T, R);
+            
+            impl<T> A<T> {
+                fn new(t: T) -> Self { A(t) }
+                fn into_b(self) -> B<T> { B(self.0) }
+            }
+            impl<T> B<T> {
+                fn into_c(self) -> C<T> { C(self.0) }
+            }
+            fn main() {
+                let c = A::new(X(42, true))
+                    .into_b()
+                    .into_c();
+            }"#,
+        );
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayHintsOptions{ parameter_hints: false, type_hints: false, chaining_hints: true, max_length: None}).unwrap(), @r###"
+        [
+            InlayHint {
+                range: [416; 465),
+                kind: ChainingHint,
+                label: "B<X<i32, bool>>",
+            },
+            InlayHint {
+                range: [416; 435),
+                kind: ChainingHint,
+                label: "A<X<i32, bool>>",
+            },
+        ]"###);
+    }
 }