C++: Add CFG test for constexpr_if

Author: ian-semmle

cpp/ql/test/library-tests/constexpr_if/cfg.expected

@@ -0,0 +1,47 @@
+| __va_list_tag::operator= | false | 64 | 64 | operator= |
+| __va_list_tag::operator= | false | 70 | 70 | operator= |
+| test | false | 121 | 121 | test |
+| test | false | 127 | 127 | declaration |
+| test | false | 133 | 133 | 1 |
+| test | false | 139 | 139 | x |
+| test | false | 145 | 145 | 1 |
+| test | false | 147 | 147 | ... = ... |
+| test | false | 150 | 150 | ExprStmt |
+| test | false | 153 | 153 | { ... } |
+| test | false | 156 | 156 | x |
+| test | false | 162 | 162 | 2 |
+| test | false | 164 | 164 | ... = ... |
+| test | false | 167 | 167 | ExprStmt |
+| test | false | 170 | 170 | { ... } |
+| test | false | 173 | 173 | if constexpr (...) ...  |
+| test | false | 179 | 179 | 0 |
+| test | false | 181 | 181 | x |
+| test | false | 187 | 187 | 3 |
+| test | false | 189 | 189 | ... = ... |
+| test | false | 192 | 192 | ExprStmt |
+| test | false | 195 | 195 | { ... } |
+| test | false | 198 | 198 | if constexpr (...) ...  |
+| test | false | 201 | 201 | return ... |
+| test | false | 204 | 204 | { ... } |
+| test | true | 127 | 173 |  |
+| test | true | 133 | 153 | T |
+| test | true | 139 | 147 |  |
+| test | true | 145 | 139 |  |
+| test | true | 147 | 198 |  |
+| test | true | 150 | 145 |  |
+| test | true | 153 | 150 |  |
+| test | true | 156 | 164 |  |
+| test | true | 162 | 156 |  |
+| test | true | 164 | 198 |  |
+| test | true | 167 | 162 |  |
+| test | true | 170 | 167 |  |
+| test | true | 173 | 133 |  |
+| test | true | 179 | 201 | F |
+| test | true | 181 | 189 |  |
+| test | true | 187 | 181 |  |
+| test | true | 189 | 201 |  |
+| test | true | 192 | 187 |  |
+| test | true | 195 | 192 |  |
+| test | true | 198 | 179 |  |
+| test | true | 201 | 121 |  |
+| test | true | 204 | 127 |  |

cpp/ql/test/library-tests/constexpr_if/cfg.ql

@@ -0,0 +1,34 @@
+// query-type: graph
+import cpp
+
+class DestructorCallEnhanced extends DestructorCall {
+    override string toString() {
+        if exists(this.getQualifier().(VariableAccess).getTarget().getName())
+        then result = "call to " + this.getQualifier().(VariableAccess).getTarget().getName() + "." + this.getTarget().getName()
+        else result = super.toString()
+    }
+}
+
+string scope(ControlFlowNode x) {
+  if exists(x.getControlFlowScope().getQualifiedName())
+  then result = x.getControlFlowScope().getQualifiedName()
+  else result = "<no scope>"
+}
+
+predicate isNode(boolean isEdge, ControlFlowNode x, ControlFlowNode y, string label) {
+    isEdge = false and x = y and label = x.toString()
+}
+
+predicate isSuccessor(boolean isEdge, ControlFlowNode x, ControlFlowNode y, string label) {
+    exists(string truelabel, string falselabel |
+           isEdge = true
+       and x.getASuccessor() = y
+       and if x.getATrueSuccessor()  = y then truelabel  = "T" else truelabel  = ""
+       and if x.getAFalseSuccessor() = y then falselabel = "F" else falselabel = ""
+       and label = truelabel + falselabel)
+}
+
+from boolean isEdge, ControlFlowNode x, ControlFlowNode y, string label
+where isNode(isEdge, x, y, label) or isSuccessor(isEdge, x, y, label)
+select scope(x), isEdge, x, y, label
+