Create rule S7417 Manual PartialOrd implementation should be avoided when Ord is derived (#4757)

* Create rule S7417

* Update rule.adoc

* Update metadata.json

* Update metadata.json

---------

Co-authored-by: sallaigy <sallaigy@users.noreply.github.com>
Co-authored-by: Gyula Sallai <gyula.sallai@sonarsource.com>

rules/S7417/metadata.json

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+{
+}

rules/S7417/rust/metadata.json

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+{
+  "title": "Manual PartialOrd implementation should be avoided when Ord is derived",
+  "type": "BUG",
+  "status": "ready",
+  "remediation": {
+    "func": "Constant\/Issue",
+    "constantCost": "5min"
+  },
+  "tags": [
+    "clippy"
+  ],
+  "defaultSeverity": "Critical",
+  "ruleSpecification": "RSPEC-7417",
+  "sqKey": "S7417",
+  "scope": "All",
+  "defaultQualityProfiles": ["Sonar way"],
+  "quickfix": "unknown",
+  "code": {
+    "impacts": {
+      "RELIABILITY": "HIGH"
+    },
+    "attribute": "LOGICAL"
+  }
+}

rules/S7417/rust/rule.adoc

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+
+== Why is this an issue?
+Manually implementing `PartialOrd` for a type that derives `Ord` can lead to inconsistencies, as the implementations of these traits must agree for sorting and other comparisons. According to the trait contract, the following must hold for any type implementing `Ord`:
+
+[source,rust]
+----
+k1.cmp(&k2) == k1.partial_cmp(&k2).unwrap()
+----
+
+Using a default-generated `Ord` implementation with an explicitly defined `PartialOrd` is a risky practice that may cause unexpected behavior.
+
+
+=== Code examples
+
+==== Noncompliant code example
+[source,rust,diff-id=1,diff-type=noncompliant]
+----
+#[derive(Ord, PartialEq, Eq)]
+struct Foo;
+
+impl PartialOrd for Foo {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        None  // Noncompliant: Manually implemented PartialOrd when Ord is derived.
+    }
+}
+----
+
+==== Compliant solution
+
+[source,rust,diff-id=1,diff-type=compliant]
+----
+#[derive(PartialEq, Eq)]
+struct Foo;
+
+impl PartialOrd for Foo {
+    fn partial_cmp(&self, other: &Foo) -> Option<Ordering> {
+        Some(self.cmp(other)) // Compliant: Manual implementation is consistent with Ord.
+    }
+}
+
+impl Ord for Foo {
+    fn cmp(&self, other: &Foo) -> Ordering {
+        // Implementation here
+    }
+}
+----
+
+Or, if a custom ordering is not needed:
+
+[source,rust,diff-id=1,diff-type=compliant]
+----
+#[derive(Ord, PartialOrd, PartialEq, Eq)]
+struct Foo; // Compliant: Both Ord and PartialOrd are derived.
+----
+
+== Resources
+=== Documentation
+
+* Clippy Lints - https://rust-lang.github.io/rust-clippy/master/index.html#derive_ord_xor_partial_ord