From feaf726b3ad83855f200ade5451c0448c95c6a31 Mon Sep 17 00:00:00 2001
From: "github-actions[bot]"
 <41898282+github-actions[bot]@users.noreply.github.com>
Date: Wed, 19 Mar 2025 14:08:57 +0000
Subject: [PATCH] Create rule S6164: Mathematical constants should not be
 hardcoded (#4690)

* Add rust to rule S6164

* Add rule description

* Update rule.adoc

* Add link to Clippy lint

---------

Co-authored-by: sallaigy <sallaigy@users.noreply.github.com>
Co-authored-by: Gyula Sallai <gyula.sallai@sonarsource.com>
Co-authored-by: yassin-kammoun-sonarsource <yassin.kammoun@sonarsource.com>
---
 rules/S6164/cfamily/metadata.json | 29 +---------------------
 rules/S6164/metadata.json         | 32 +++++++++++++++++++++++++
 rules/S6164/rust/metadata.json    |  7 ++++++
 rules/S6164/rust/rule.adoc        | 40 +++++++++++++++++++++++++++++++
 4 files changed, 80 insertions(+), 28 deletions(-)
 create mode 100644 rules/S6164/rust/metadata.json
 create mode 100644 rules/S6164/rust/rule.adoc

diff --git a/rules/S6164/cfamily/metadata.json b/rules/S6164/cfamily/metadata.json
index 730b341938..536598314f 100644
--- a/rules/S6164/cfamily/metadata.json
+++ b/rules/S6164/cfamily/metadata.json
@@ -1,35 +1,8 @@
 {
-  "title": "Mathematical constants should not be hardcoded",
-  "type": "CODE_SMELL",
-  "code": {
-    "impacts": {
-      "MAINTAINABILITY": "MEDIUM"
-    },
-    "attribute": "CLEAR"
-  },
-  "status": "ready",
-  "remediation": {
-    "func": "Constant\/Issue",
-    "constantCost": "5min"
-  },
   "tags": [
     "since-c++20",
     "clumsy"
   ],
-  "extra": {
-    "replacementRules": [
-
-    ],
-    "legacyKeys": [
-
-    ]
-  },
-  "defaultSeverity": "Major",
-  "ruleSpecification": "RSPEC-6164",
-  "sqKey": "S6164",
-  "scope": "All",
-  "defaultQualityProfiles": [
-    "Sonar way"
-  ],
   "quickfix": "unknown"
 }
+  
\ No newline at end of file
diff --git a/rules/S6164/metadata.json b/rules/S6164/metadata.json
index 2c63c08510..16cf484a94 100644
--- a/rules/S6164/metadata.json
+++ b/rules/S6164/metadata.json
@@ -1,2 +1,34 @@
 {
+  "title": "Mathematical constants should not be hardcoded",
+  "type": "CODE_SMELL",
+  "code": {
+    "impacts": {
+      "MAINTAINABILITY": "MEDIUM"
+    },
+    "attribute": "CLEAR"
+  },
+  "status": "ready",
+  "remediation": {
+    "func": "Constant\/Issue",
+    "constantCost": "5min"
+  },
+  "tags": [
+    "clumsy"
+  ],
+  "extra": {
+    "replacementRules": [
+
+    ],
+    "legacyKeys": [
+
+    ]
+  },
+  "defaultSeverity": "Major",
+  "ruleSpecification": "RSPEC-6164",
+  "sqKey": "S6164",
+  "scope": "All",
+  "defaultQualityProfiles": [
+    "Sonar way"
+  ],
+  "quickfix": "unknown"
 }
diff --git a/rules/S6164/rust/metadata.json b/rules/S6164/rust/metadata.json
new file mode 100644
index 0000000000..d5b290c212
--- /dev/null
+++ b/rules/S6164/rust/metadata.json
@@ -0,0 +1,7 @@
+{
+  "tags": [
+    "clippy",
+    "clumsy"
+  ],
+  "quickfix": "unknown"
+}
diff --git a/rules/S6164/rust/rule.adoc b/rules/S6164/rust/rule.adoc
new file mode 100644
index 0000000000..0a7f9276b1
--- /dev/null
+++ b/rules/S6164/rust/rule.adoc
@@ -0,0 +1,40 @@
+== Why is this an issue?
+
+Floating-point literals that approximate constants defined in `std::f32::consts` or `std::f64::consts` should be replaced with the predefined constants.  Using the standard library constants ensures higher precision and avoids potential rounding errors that can occur when manually approximating these values.  It also improves code readability and maintainability, as it clearly indicates the intended constant value.
+
+=== Noncompliant code example
+
+[source,rust,diff-id=1,diff-type=noncompliant]
+----
+let x = 3.14; // Noncompliant: Approximates PI
+let y = 1_f64 / 3.1415926535; // Noncompliant: Approximates FRAC_1_PI
+----
+
+=== Compliant solution
+
+[source,rust,diff-id=1,diff-type=compliant]
+----
+use std::f32::consts::PI;
+use std::f64::consts::FRAC_1_PI;
+
+let x = PI; // Compliant: Uses the predefined PI constant
+let y = FRAC_1_PI; // Compliant: Uses the predefined FRAC_1_PI constant
+----
+
+== Resources
+
+=== Documentation
+
+* Clippy Lints - https://rust-lang.github.io/rust-clippy/master/index.html#approx_constant
+
+
+ifdef::env-github,rspecator-view[]
+'''
+== Comments And Links
+(visible only on this page)
+
+=== is related to: S2904
+
+=== is related to: S109
+
+endif::env-github,rspecator-view[]