Declarations7: add RULE-8-12

Author: knewbury01

.vscode/tasks.json

@@ -208,6 +208,7 @@
                 "Declarations2",
                 "Declarations3",
                 "Declarations4",
+                "Declarations7",
                 "Exceptions1",
                 "Exceptions2",
                 "Expressions",

c/misra/src/rules/RULE-8-12/ValueImplicitEnumerationConstantNotUnique.ql

@@ -0,0 +1,38 @@
+/**
+ * @id c/misra/value-implicit-enumeration-constant-not-unique
+ * @name RULE-8-12: Within an enumerator list, the value of an implicitly-specified enumeration constant shall be unique
+ * @description Using an implicitly specified enumeration constant that is not unique (with respect
+ *              to an explicitly specified constant) can lead to unexpected program behaviour.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity error
+ * @tags external/misra/id/rule-8-12
+ *       correctness
+ *       readability
+ *       external/misra/obligation/required
+ */
+
+import cpp
+import codingstandards.c.misra
+
+/**
+ * An `EnumConstant` that has an implicitly specified value:
+ * `enum e { explicit = 1, implicit }`
+ */
+class ImplicitlySpecifiedEnumConstant extends EnumConstant {
+  ImplicitlySpecifiedEnumConstant() {
+    //implicitly specified have an initializer with ___location: `file://:0:0:0:0`
+    not this.getInitializer().getLocation().getFile() = this.getFile()
+  }
+}
+
+from EnumConstant exp, ImplicitlySpecifiedEnumConstant imp
+where
+  not isExcluded(exp, Declarations7Package::valueImplicitEnumerationConstantNotUniqueQuery()) and
+  not isExcluded(imp, Declarations7Package::valueImplicitEnumerationConstantNotUniqueQuery()) and
+  not exp = imp and
+  imp.getValue() = exp.getValue() and
+  imp.getDeclaringEnum() = exp.getDeclaringEnum() and
+  //can technically be the same declared enum across multiple headers but those are not relevant to this rule
+  imp.getFile() = exp.getFile()
+select imp, "Nonunique value of enum constant compared to $@", exp, exp.getName()

c/misra/test/rules/RULE-8-12/ValueImplicitEnumerationConstantNotUnique.expected

@@ -0,0 +1 @@
+| test.c:3:18:3:19 | c4 | Nonunique value of enum constant compared to $@ | test.c:3:22:3:23 | c5 | c5 |

c/misra/test/rules/RULE-8-12/ValueImplicitEnumerationConstantNotUnique.qlref

@@ -0,0 +1 @@
+rules/RULE-8-12/ValueImplicitEnumerationConstantNotUnique.ql

c/misra/test/rules/RULE-8-12/test.c

@@ -0,0 +1,4 @@
+enum e {c = 3};                  // COMPLIANT
+enum e1 {c1 = 3, c2};             // COMPLIANT
+enum e3 {c3 = 3, c4, c5 = 4};     // NON_COMPLIANT
+enum e4 {c6 = 3, c7, c8, c9 = 6}; // COMPLIANT

cpp/common/src/codingstandards/cpp/exclusions/c/Declarations7.qll

@@ -0,0 +1,26 @@
+//** THIS FILE IS AUTOGENERATED, DO NOT MODIFY DIRECTLY.  **/
+import cpp
+import RuleMetadata
+import codingstandards.cpp.exclusions.RuleMetadata
+
+newtype Declarations7Query = TValueImplicitEnumerationConstantNotUniqueQuery()
+
+predicate isDeclarations7QueryMetadata(Query query, string queryId, string ruleId, string category) {
+  query =
+    // `Query` instance for the `valueImplicitEnumerationConstantNotUnique` query
+    Declarations7Package::valueImplicitEnumerationConstantNotUniqueQuery() and
+  queryId =
+    // `@id` for the `valueImplicitEnumerationConstantNotUnique` query
+    "c/misra/value-implicit-enumeration-constant-not-unique" and
+  ruleId = "RULE-8-12" and
+  category = "required"
+}
+
+module Declarations7Package {
+  Query valueImplicitEnumerationConstantNotUniqueQuery() {
+    //autogenerate `Query` type
+    result =
+      // `Query` type for `valueImplicitEnumerationConstantNotUnique` query
+      TQueryC(TDeclarations7PackageQuery(TValueImplicitEnumerationConstantNotUniqueQuery()))
+  }
+}

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

@@ -17,6 +17,7 @@ import Declarations1
 import Declarations2
 import Declarations3
 import Declarations4
+import Declarations7
 import Expressions
 import IO1
 import IO2
@@ -57,6 +58,7 @@ newtype TCQuery =
   TDeclarations2PackageQuery(Declarations2Query q) or
   TDeclarations3PackageQuery(Declarations3Query q) or
   TDeclarations4PackageQuery(Declarations4Query q) or
+  TDeclarations7PackageQuery(Declarations7Query q) or
   TExpressionsPackageQuery(ExpressionsQuery q) or
   TIO1PackageQuery(IO1Query q) or
   TIO2PackageQuery(IO2Query q) or
@@ -97,6 +99,7 @@ predicate isQueryMetadata(Query query, string queryId, string ruleId, string cat
   isDeclarations2QueryMetadata(query, queryId, ruleId, category) or
   isDeclarations3QueryMetadata(query, queryId, ruleId, category) or
   isDeclarations4QueryMetadata(query, queryId, ruleId, category) or
+  isDeclarations7QueryMetadata(query, queryId, ruleId, category) or
   isExpressionsQueryMetadata(query, queryId, ruleId, category) or
   isIO1QueryMetadata(query, queryId, ruleId, category) or
   isIO2QueryMetadata(query, queryId, ruleId, category) or

rule_packages/c/Declarations7.json

@@ -0,0 +1,24 @@
+{
+  "MISRA-C-2012": {
+    "RULE-8-12": {
+      "properties": {
+        "obligation": "required"
+      },
+      "queries": [
+        {
+          "description": "Using an implicitly specified enumeration constant that is not unique (with respect to an explicitly specified constant) can lead to unexpected program behaviour.",
+          "kind": "problem",
+          "name": "Within an enumerator list, the value of an implicitly-specified enumeration constant shall be unique",
+          "precision": "very-high",
+          "severity": "error",
+          "short_name": "ValueImplicitEnumerationConstantNotUnique",
+          "tags": [
+            "correctness",
+            "readability"
+          ]
+        }
+      ],
+      "title": "Within an enumerator list, the value of an implicitly-specified enumeration constant shall be unique"
+    }
+  }
+}

rules.csv

@@ -657,7 +657,7 @@ c,MISRA-C-2012,RULE-8-8,Yes,Required,,,The static storage class specifier shall
 c,MISRA-C-2012,RULE-8-9,Yes,Advisory,,,An object should be defined at block scope if its identifier only appears in a single function,M3-4-1,Declarations,Medium,
 c,MISRA-C-2012,RULE-8-10,Yes,Required,,,An inline function shall be declared with the static storage class,,Declarations,Medium,
 c,MISRA-C-2012,RULE-8-11,Yes,Advisory,,,"When an array with external linkage is declared, its size should be explicitly specified",,Declarations,Medium,
-c,MISRA-C-2012,RULE-8-12,Yes,Required,,,"Within an enumerator list, the value of an implicitly-specified enumeration constant shall be unique",,Declarations,Medium,
+c,MISRA-C-2012,RULE-8-12,Yes,Required,,,"Within an enumerator list, the value of an implicitly-specified enumeration constant shall be unique",,Declarations7,Medium,
 c,MISRA-C-2012,RULE-8-13,Yes,Advisory,,,A pointer should point to a const-qualified type whenever possible,,Pointers1,Medium,
 c,MISRA-C-2012,RULE-8-14,Yes,Required,,,The restrict type qualifier shall not be used,,Banned,Easy,
 c,MISRA-C-2012,RULE-9-1,Yes,Mandatory,,,The value of an object with automatic storage duration shall not be read before it has been set,,InvalidMemory,Medium,