fix: Ensure dep/feature activates the dependency on 2024

This doesn't revert the last commit of rust-lang#14018 so that it works properly
on Editions 2021 and 2024.

Fixes rust-lang#14016

src/cargo/util/toml/mod.rs

@@ -322,7 +322,7 @@ fn resolve_toml(
             });
         resolved_toml.package = Some(resolved_package);
 
-        resolved_toml.features = resolve_features(original_toml.features.as_ref())?;
+        resolved_toml.features = resolve_features(original_toml.features.as_ref(), edition)?;
 
         resolved_toml.lib = targets::resolve_lib(
             original_toml.lib.as_ref(),
@@ -691,11 +691,34 @@ fn default_readme_from_package_root(package_root: &Path) -> Option<String> {
 #[tracing::instrument(skip_all)]
 fn resolve_features(
     original_features: Option<&BTreeMap<manifest::FeatureName, Vec<String>>>,
+    edition: Edition,
 ) -> CargoResult<Option<BTreeMap<manifest::FeatureName, Vec<String>>>> {
-    let Some(resolved_features) = original_features.cloned() else {
+    let Some(mut resolved_features) = original_features.cloned() else {
         return Ok(None);
     };
 
+    if Edition::Edition2024 <= edition {
+        for activations in resolved_features.values_mut() {
+            let mut deps = Vec::new();
+            for feature_value in activations.iter() {
+                let feature_value = FeatureValue::new(InternedString::new(feature_value));
+                let FeatureValue::DepFeature {
+                    dep_name,
+                    dep_feature: _,
+                    weak: false,
+                } = feature_value
+                else {
+                    continue;
+                };
+                let dep = FeatureValue::Dep { dep_name }.to_string();
+                if !activations.contains(&dep) {
+                    deps.push(dep);
+                }
+            }
+            activations.extend(deps);
+        }
+    }
+
     Ok(Some(resolved_features))
 }
 

tests/testsuite/features.rs

@@ -1890,17 +1890,27 @@ fn strong_dep_feature_edition2024() {
 
     p.cargo("metadata")
         .masquerade_as_nightly_cargo(&["edition2024"])
-        .with_status(101)
-        .with_stderr_data(str![[r#"
-[ERROR] feature `optional_dep` includes `optional_dep/foo`, but `optional_dep` is not a dependency
- --> Cargo.toml:9:32
-  |
-9 |                 optional_dep = ["optional_dep/foo"]
-  |                                ^^^^^^^^^^^^^^^^^^^^
-  |
-[ERROR] failed to parse manifest at `[ROOT]/foo/Cargo.toml`
-
-"#]])
+        .with_stdout_data(
+            str![[r#"
+{
+  "metadata": null,
+  "packages": [
+    {
+      "features": {
+        "optional_dep": [
+          "optional_dep/foo",
+          "dep:optional_dep"
+        ]
+      },
+      "name": "foo",
+      "...": "{...}"
+    }
+  ],
+  "...": "{...}"
+}
+"#]]
+            .json(),
+        )
         .run();
 }