diff --git a/rules/S7422/metadata.json b/rules/S7422/metadata.json
new file mode 100644
index 0000000000..2c63c08510
--- /dev/null
+++ b/rules/S7422/metadata.json
@@ -0,0 +1,2 @@
+{
+}
diff --git a/rules/S7422/rust/metadata.json b/rules/S7422/rust/metadata.json
new file mode 100644
index 0000000000..5e9db195ac
--- /dev/null
+++ b/rules/S7422/rust/metadata.json
@@ -0,0 +1,24 @@
+{
+  "title": "Unit values should not be hashed",
+  "type": "BUG",
+  "status": "ready",
+  "remediation": {
+    "func": "Constant\/Issue",
+    "constantCost": "5min"
+  },
+  "tags": [
+    "clippy"
+  ],
+  "defaultSeverity": "Major",
+  "ruleSpecification": "RSPEC-7422",
+  "sqKey": "S7422",
+  "scope": "All",
+  "defaultQualityProfiles": ["Sonar way"],
+  "quickfix": "unknown",
+  "code": {
+    "impacts": {
+      "RELIABILITY": "HIGH"
+    },
+    "attribute": "LOGICAL"
+  }
+}
diff --git a/rules/S7422/rust/rule.adoc b/rules/S7422/rust/rule.adoc
new file mode 100644
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+++ b/rules/S7422/rust/rule.adoc
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+== Why is this an issue?
+
+Hashing a unit value doesn't accomplish anything because the implementation of `Hash` for `()` is a no-op. This can lead to confusion or misleading code, as it implies some hashing operation is actually taking place, when in reality it does nothing.
+
+=== Code examples
+
+==== Noncompliant code example
+
+[source,rust,diff-id=1,diff-type=noncompliant]
+----
+enum Foo { Empty, WithValue(u8) }
+use Foo::*;
+
+let mut state = DefaultHasher::new();
+let my_enum = Foo::Empty;
+
+match my_enum {
+    Empty => ().hash(&mut state), // Noncompliant
+    WithValue(x) => x.hash(&mut state),
+}
+----
+
+==== Compliant solution
+
+[source,rust,diff-id=1,diff-type=compliant]
+----
+enum Foo { Empty, WithValue(u8) }
+use Foo::*;
+
+let mut state = DefaultHasher::new();
+let my_enum = Foo::Empty;
+
+match my_enum {
+    Empty => 0_u8.hash(&mut state), // Compliant
+    WithValue(x) => x.hash(&mut state),
+}
+----
+
+== Resources
+=== Documentation
+
+* Clippy Lints - https://rust-lang.github.io/rust-clippy/master/index.html#unit_hash