Add Banned8

Author: jeongsoolee09

cpp/common/src/codingstandards/cpp/exclusions/cpp/Banned8.qll

@@ -0,0 +1,26 @@
+//** THIS FILE IS AUTOGENERATED, DO NOT MODIFY DIRECTLY.  **/
+import cpp
+import RuleMetadata
+import codingstandards.cpp.exclusions.RuleMetadata
+
+newtype Banned8Query = TBuiltInUnaryPlusOperatorShouldNotBeUsedQuery()
+
+predicate isBanned8QueryMetadata(Query query, string queryId, string ruleId, string category) {
+  query =
+    // `Query` instance for the `builtInUnaryPlusOperatorShouldNotBeUsed` query
+    Banned8Package::builtInUnaryPlusOperatorShouldNotBeUsedQuery() and
+  queryId =
+    // `@id` for the `builtInUnaryPlusOperatorShouldNotBeUsed` query
+    "cpp/misra/built-in-unary-plus-operator-should-not-be-used" and
+  ruleId = "RULE-8-3-2" and
+  category = "advisory"
+}
+
+module Banned8Package {
+  Query builtInUnaryPlusOperatorShouldNotBeUsedQuery() {
+    //autogenerate `Query` type
+    result =
+      // `Query` type for `builtInUnaryPlusOperatorShouldNotBeUsed` query
+      TQueryCPP(TBanned8PackageQuery(TBuiltInUnaryPlusOperatorShouldNotBeUsedQuery()))
+  }
+}

cpp/common/src/codingstandards/cpp/exclusions/cpp/RuleMetadata.qll

@@ -4,6 +4,7 @@ import codingstandards.cpp.exclusions.RuleMetadata
 //** Import packages for this language **/
 import Allocations
 import Banned1
+import Banned8
 import BannedAPIs
 import BannedFunctions
 import BannedLibraries
@@ -95,6 +96,7 @@ import VirtualFunctions
 newtype TCPPQuery =
   TAllocationsPackageQuery(AllocationsQuery q) or
   TBanned1PackageQuery(Banned1Query q) or
+  TBanned8PackageQuery(Banned8Query q) or
   TBannedAPIsPackageQuery(BannedAPIsQuery q) or
   TBannedFunctionsPackageQuery(BannedFunctionsQuery q) or
   TBannedLibrariesPackageQuery(BannedLibrariesQuery q) or
@@ -186,6 +188,7 @@ newtype TCPPQuery =
 predicate isQueryMetadata(Query query, string queryId, string ruleId, string category) {
   isAllocationsQueryMetadata(query, queryId, ruleId, category) or
   isBanned1QueryMetadata(query, queryId, ruleId, category) or
+  isBanned8QueryMetadata(query, queryId, ruleId, category) or
   isBannedAPIsQueryMetadata(query, queryId, ruleId, category) or
   isBannedFunctionsQueryMetadata(query, queryId, ruleId, category) or
   isBannedLibrariesQueryMetadata(query, queryId, ruleId, category) or

cpp/misra/src/rules/RULE-8-3-2/BuiltInUnaryPlusOperatorShouldNotBeUsed.ql

@@ -0,0 +1,21 @@
+/**
+ * @id cpp/misra/built-in-unary-plus-operator-should-not-be-used
+ * @name RULE-8-3-2: The built-in unary + operator should not be used
+ * @description Using the built-in unary '+' operator may trigger unexpected implicit type
+ *              conversions.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity error
+ * @tags external/misra/id/rule-8-3-2
+ *       scope/single-translation-unit
+ *       correctness
+ *       external/misra/enforcement/decidable
+ *       external/misra/obligation/advisory
+ */
+
+import cpp
+import codingstandards.cpp.misra
+
+from UnaryPlusExpr e
+where not e.isFromUninstantiatedTemplate(_)
+select e, "Use of built-in unary + operator."

cpp/misra/test/rules/RULE-8-3-2/BuiltInUnaryPlusOperatorShouldNotBeUsed.expected

@@ -0,0 +1,18 @@
+| test.cpp:12:12:12:14 | + ... | Use of built-in unary + operator. |
+| test.cpp:15:12:15:14 | + ... | Use of built-in unary + operator. |
+| test.cpp:18:12:18:15 | + ... | Use of built-in unary + operator. |
+| test.cpp:21:12:21:14 | + ... | Use of built-in unary + operator. |
+| test.cpp:24:12:24:14 | + ... | Use of built-in unary + operator. |
+| test.cpp:26:12:26:27 | + ... | Use of built-in unary + operator. |
+| test.cpp:29:18:29:25 | + ... | Use of built-in unary + operator. |
+| test.cpp:30:12:30:27 | + ... | Use of built-in unary + operator. |
+| test.cpp:33:12:33:13 | + ... | Use of built-in unary + operator. |
+| test.cpp:34:12:34:15 | + ... | Use of built-in unary + operator. |
+| test.cpp:35:12:35:16 | + ... | Use of built-in unary + operator. |
+| test.cpp:38:7:38:8 | + ... | Use of built-in unary + operator. |
+| test.cpp:42:12:42:15 | + ... | Use of built-in unary + operator. |
+| test.cpp:45:12:45:13 | + ... | Use of built-in unary + operator. |
+| test.cpp:48:12:48:15 | + ... | Use of built-in unary + operator. |
+| test.cpp:64:10:64:13 | + ... | Use of built-in unary + operator. |
+| test.cpp:64:10:64:13 | + ... | Use of built-in unary + operator. |
+| test.cpp:75:14:75:17 | + ... | Use of built-in unary + operator. |

cpp/misra/test/rules/RULE-8-3-2/BuiltInUnaryPlusOperatorShouldNotBeUsed.qlref

@@ -0,0 +1 @@
+rules/RULE-8-3-2/BuiltInUnaryPlusOperatorShouldNotBeUsed.ql

cpp/misra/test/rules/RULE-8-3-2/test.cpp

@@ -0,0 +1,76 @@
+#include <cstdint>
+
+// Helper types
+enum UnscopedEnum { A, B, C };
+enum SmallEnum : uint8_t { S1, S2 };
+
+uint8_t operator+(SmallEnum e) { return static_cast<uint8_t>(e); }
+
+void test_unary_plus() {
+  // === NON-COMPLIANT: integral promotion ===
+  uint8_t u8 = 1;
+  auto a = +u8; // NON_COMPLIANT: promotes to int
+
+  int8_t i8 = 1;
+  auto b = +i8; // NON_COMPLIANT: promotes to int
+
+  uint16_t u16 = 1;
+  auto c = +u16; // NON_COMPLIANT: promotes to int
+
+  char ch = 'x';
+  auto d = +ch; // NON_COMPLIANT: promotes to int
+
+  bool bl = true;
+  auto e = +bl; // NON_COMPLIANT: promotes to int
+
+  auto f = +UnscopedEnum::A; // NON_COMPLIANT: promotes to int
+
+  // === NON_COMPLIANT: function/lambda decay ===
+  void (*fp)() = +[]() {};   // NON_COMPLIANT: lambda decays to pointer
+  auto g = +test_unary_plus; // NON_COMPLIANT: function decays to pointer
+
+  // === NON_COMPLIANT: literals and expressions ===
+  auto h = +1;    // NON_COMPLIANT: unary + on literal
+  auto i = +'a';  // NON_COMPLIANT: promotes char to int
+  auto j = +true; // NON_COMPLIANT: promotes bool to int
+
+  int x;
+  x = +1; // NON_COMPLIANT: unary +, not +=
+
+  // === NON_COMPLIANT: larger types (still built-in +) ===
+  int i32 = 1;
+  auto k = +i32; // NON_COMPLIANT: built-in unary +
+
+  long l = 1;
+  auto m = +l; // NON_COMPLIANT: built-in unary +
+
+  double dbl = 1.0;
+  auto n = +dbl; // NON_COMPLIANT: built-in unary +
+
+  // === COMPLIANT: user-defined operator+ ===
+  auto o = +SmallEnum::S1;           // COMPLIANT: calls user-defined operator+
+  auto p = operator+(SmallEnum::S2); // COMPLIANT: explicit call
+
+  // === COMPLIANT: not unary + ===
+  auto q = 1 + 2;   // COMPLIANT: binary +
+  auto r = u8 + u8; // COMPLIANT: binary +
+
+  int y = 0;
+  y += 1; // COMPLIANT: compound assignment
+}
+
+// === NON_COMPLIANT: in other contexts ===
+template <typename T> T promote(T val) {
+  return +val; // NON_COMPLIANT (when T is built-in type)
+}
+
+void test_template() {
+  promote(uint8_t{1}); // Instantiates NON_COMPLIANT case
+  promote(1);          // Instantiates NON_COMPLIANT case
+}
+
+// === NON_COMPLIANT: array decay ===
+void test_array() {
+  int arr[5];
+  auto ptr = +arr; // NON_COMPLIANT: array decays to pointer
+}

rule_packages/cpp/Banned8.json

@@ -0,0 +1,25 @@
+{
+  "MISRA-C++-2023": {
+    "RULE-8-3-2": {
+      "properties": {
+        "enforcement": "decidable",
+        "obligation": "advisory"
+      },
+      "queries": [
+        {
+          "description": "Using the built-in unary '+' operator may trigger unexpected implicit type conversions.",
+          "kind": "problem",
+          "name": "The built-in unary + operator should not be used",
+          "precision": "very-high",
+          "severity": "error",
+          "short_name": "BuiltInUnaryPlusOperatorShouldNotBeUsed",
+          "tags": [
+            "scope/single-translation-unit",
+            "correctness"
+          ]
+        }
+      ],
+      "title": "The built-in unary + operator should not be used"
+    }
+  }
+}

rules.csv

@@ -1,5 +1,5 @@
 Language,Standard,ID,Supportable,Obligation level,Enforcement level,Allocated target,Description,Similar,Package,Difficulty,Justification for querability level
-cpp,AUTOSAR,A0-1-1,Yes,Required,Automated,Implementation,A project shall not contain instances of non-volatile variables being given values that are not subsequently used.,M0-1-6,DeadCode,Medium,
+cpp,AUTOSAR,-1,Yes,Required,Automated,Implementation,A project shall not contain instances of non-volatile variables being given values that are not subsequently used.,M0-1-6,DeadCode,Medium,
 cpp,AUTOSAR,A0-1-2,Yes,Required,Automated,Implementation,The value returned by a function having a non-void return type that is not an overloaded operator shall be used.,M0-1-7,DeadCode,Easy,
 cpp,AUTOSAR,A0-1-3,Yes,Required,Automated,Implementation,"Every function defined in an anonymous namespace, or static function with internal linkage, or private member function shall be used.",M0-1-10,DeadCode,Easy,
 cpp,AUTOSAR,A0-1-4,Yes,Required,Automated,Implementation,There shall be no unused named parameters in non-virtual functions.,,DeadCode,Easy,
@@ -894,7 +894,7 @@ cpp,MISRA-C++-2023,RULE-8-2-9,Yes,Required,Decidable,Single Translation Unit,The
 cpp,MISRA-C++-2023,RULE-8-2-10,Yes,Required,Undecidable,System,"Functions shall not call themselves, either directly or indirectly",A7-5-2,ImportMisra23,Import,
 cpp,MISRA-C++-2023,RULE-8-2-11,Yes,Required,Decidable,Single Translation Unit,An argument passed via ellipsis shall have an appropriate type,,Preconditions,Easy,
 cpp,MISRA-C++-2023,RULE-8-3-1,Yes,Advisory,Decidable,Single Translation Unit,The built-in unary - operator should not be applied to an expression of unsigned type,M5-3-2,ImportMisra23,Import,
-cpp,MISRA-C++-2023,RULE-8-3-2,Yes,Advisory,Decidable,Single Translation Unit,The built-in unary + operator should not be used,,Banned,Easy,
+cpp,MISRA-C++-2023,RULE-8-3-2,Yes,Advisory,Decidable,Single Translation Unit,The built-in unary + operator should not be used,,Banned8,Easy,
 cpp,MISRA-C++-2023,RULE-8-7-1,Yes,Required,Undecidable,System,Pointer arithmetic shall not form an invalid pointer,ARR30-C,Memory1,Easy,
 cpp,MISRA-C++-2023,RULE-8-7-2,Yes,Required,Undecidable,System,Subtraction between pointers shall only be applied to pointers that address elements of the same array,ARR36-C,Memory2,Easy,
 cpp,MISRA-C++-2023,RULE-8-9-1,Yes,Required,Undecidable,System,"The built-in relational operators >, >=, < and <= shall not be applied to objects of pointer type, except where they point to elements of the same array",ARR36-C,Memory3,Easy,