fix(toml): Disallow inheriting of dependency public status

src/cargo/util/toml/mod.rs

@@ -118,10 +118,10 @@ fn read_manifest_from_str(
     {
         for (name, dep) in deps {
             if dep.is_optional() {
-                bail!(
-                    "{} is optional, but workspace dependencies cannot be optional",
-                    name
-                );
+                bail!("{name} is optional, but workspace dependencies cannot be optional",);
+            }
+            if dep.is_public() {
+                bail!("{name} is public, but workspace dependencies cannot be public",);
             }
         }
     }
@@ -1667,11 +1667,6 @@ fn inner_dependency_inherit_with<'a>(
                     }
                     _ => {}
                 }
-                // Inherit the workspace configuration for `public` unless
-                // it's explicitly specified for this dependency.
-                if let Some(public) = dependency.public {
-                    d.public = Some(public);
-                }
                 d.features = match (d.features.clone(), dependency.features.clone()) {
                     (Some(dep_feat), Some(inherit_feat)) => Some(
                         dep_feat

src/cargo/util_schemas/manifest.rs

@@ -534,6 +534,13 @@ impl TomlDependency {
         }
     }
 
+    pub fn is_public(&self) -> bool {
+        match self {
+            TomlDependency::Detailed(d) => d.public.unwrap_or(false),
+            TomlDependency::Simple(..) => false,
+        }
+    }
+
     pub fn unused_keys(&self) -> Vec<String> {
         match self {
             TomlDependency::Simple(_) => vec![],

src/doc/src/reference/unstable.md

@@ -304,6 +304,9 @@ my_dep = { version = "1.2.3", public = true }
 private_dep = "2.0.0" # Will be 'private' by default
 ```
 
+Documentation updates:
+- For workspace's "The `dependencies` table" section, include `public` as an unsupported field for `workspace.dependencies`
+
 ## msrv-policy
 - [#9930](https://github.com/rust-lang/cargo/issues/9930) (MSRV-aware resolver)
 - [#10653](https://github.com/rust-lang/cargo/issues/10653) (MSRV-aware cargo-add)

tests/testsuite/pub_priv.rs

@@ -199,7 +199,7 @@ Caused by:
 }
 
 #[cargo_test(nightly, reason = "exported_private_dependencies lint is unstable")]
-fn workspace_dep_made_public() {
+fn workspace_pub_disallowed() {
     Package::new("foo1", "0.1.0")
         .file("src/lib.rs", "pub struct FromFoo;")
         .publish();
@@ -244,5 +244,14 @@ fn workspace_dep_made_public() {
 
     p.cargo("check")
         .masquerade_as_nightly_cargo(&["public-dependency"])
+        .with_status(101)
+        .with_stderr(
+            "\
+error: failed to parse manifest at `[CWD]/Cargo.toml`
+
+Caused by:
+  foo2 is public, but workspace dependencies cannot be public
+",
+        )
         .run()
 }