Improve errors for TOML fields that support workspace inheritance

Cargo.toml

@@ -52,6 +52,7 @@ semver = { version = "1.0.3", features = ["serde"] }
 serde = { version = "1.0.123", features = ["derive"] }
 serde_ignored = "0.1.0"
 serde_json = { version = "1.0.30", features = ["raw_value"] }
+serde-value = "0.7.0"
 shell-escape = "0.1.4"
 strip-ansi-escapes = "0.1.0"
 tar = { version = "0.4.38", default-features = false }

src/cargo/util/toml/mod.rs

@@ -1007,13 +1007,30 @@ where
 /// Enum that allows for the parsing of `field.workspace = true` in a Cargo.toml
 ///
 /// It allows for things to be inherited from a workspace or defined as needed
-#[derive(Deserialize, Serialize, Clone, Debug)]
+#[derive(Serialize, Clone, Debug)]
 #[serde(untagged)]
 pub enum MaybeWorkspace<T> {
     Workspace(TomlWorkspaceField),
     Defined(T),
 }
 
+impl<'de, T: Deserialize<'de>> de::Deserialize<'de> for MaybeWorkspace<T> {
+    fn deserialize<D>(deserializer: D) -> Result<MaybeWorkspace<T>, D::Error>
+    where
+        D: de::Deserializer<'de>,
+    {
+        let value = serde_value::Value::deserialize(deserializer)?;
+        if let Ok(workspace) = TomlWorkspaceField::deserialize(serde_value::ValueDeserializer::<
+            D::Error,
+        >::new(value.clone()))
+        {
+            return Ok(MaybeWorkspace::Workspace(workspace));
+        }
+        T::deserialize(serde_value::ValueDeserializer::<D::Error>::new(value))
+            .map(MaybeWorkspace::Defined)
+    }
+}
+
 impl<T> MaybeWorkspace<T> {
     fn resolve<'a>(
         self,

tests/testsuite/metadata.rs

@@ -1730,6 +1730,30 @@ Caused by:
         .run();
 }
 
+#[cargo_test]
+fn cargo_metadata_with_invalid_version_field() {
+    let p = project()
+        .file("src/foo.rs", "")
+        .file(
+            "Cargo.toml",
+            r#"
+                [package]
+                version = 1
+            "#,
+        )
+        .build();
+
+    p.cargo("metadata")
+        .with_status(101)
+        .with_stderr(
+            r#"[ERROR] failed to parse manifest at `[..]`
+
+Caused by:
+  invalid type: integer `1`, expected SemVer version for key `package.version`"#,
+        )
+        .run();
+}
+
 const MANIFEST_OUTPUT: &str = r#"
 {
     "packages": [{