QL: Merge pull request #17 from github/first-query

Add the `ql/primary-ql-class-consistency` query

Author: erik-krogh

ql/src/codeql_ql/ast/Ast.qll

@@ -280,7 +280,7 @@ class TypeExpr extends TType, AstNode {
 
   TypeExpr() { this = TType(type) }
 
-  override string getAPrimaryQlClass() { result = "Type" }
+  override string getAPrimaryQlClass() { result = "TypeExpr" }
 
   /**
    * Gets the class name for the type.
@@ -767,7 +767,11 @@ class String extends Literal {
   override string getAPrimaryQlClass() { result = "String" }
 
   /** Gets the string value of this literal. */
-  string getValue() { result = lit.getChild().(Generated::String).getValue() }
+  string getValue() {
+    exists(string raw | raw = lit.getChild().(Generated::String).getValue() |
+      result = raw.substring(1, raw.length() - 1)
+    )
+  }
 }
 
 /** An integer literal. */

ql/src/codeql_ql/ast/internal/AstNodes.qll

@@ -64,8 +64,8 @@ class TFormula =
 class TBinOpExpr = TAddSubExpr or TMulDivModExpr;
 
 class TExpr =
-  TBinOpExpr or TLiteral or TAggregate or TExprAggregate or TIdentifier or TInlineCast or TCall or TUnaryExpr or
-      TExprAnnotation or TDontCare or TRange or TSet;
+  TBinOpExpr or TLiteral or TAggregate or TExprAggregate or TIdentifier or TInlineCast or TCall or
+      TUnaryExpr or TExprAnnotation or TDontCare or TRange or TSet;
 
 class TCall = TPredicateCall or TMemberCall or TNoneCall or TAnyCall;
 

ql/src/queries/style/GetAPrimaryQlClassConsistency.ql

@@ -0,0 +1,27 @@
+/**
+ * @name Inconsistent getAPrimaryQlClass predicate
+ * @description A getAPrimaryQlClass predicate should result in the name of the class.
+ * @kind problem
+ * @problem.severity error
+ * @id ql/primary-ql-class-consistency
+ * @tags correctness
+ * @precision low
+ */
+
+import ql
+
+from ClassPredicate pred, String constant
+where
+  exists(string className, string constantName |
+    pred.getParent().getName() = className and
+    pred.getName() = "getAPrimaryQlClass" and
+    constant = pred.getBody().(ComparisonFormula).getRightOperand() and
+    constant.(String).getValue() = constantName and
+    // might be "Foo::classname", detect by matching with a regexp
+    not constantName.regexpMatch(".*\\b" + className + "$") and
+    // ignore constants with "?" in them
+    not constantName.regexpMatch(".*\\?.*")
+  )
+select pred,
+  "The getAPrimaryQlClass predicate $@ instead of the class name \"" + pred.getParent().getName() +
+    "\".", constant, "results in \"" + constant.getValue() + "\""

ql/test/printAst/Foo.qll

@@ -21,5 +21,5 @@ predicate calls(Foo f) {
   or
   f = any(Foo f)
   or
-  ((((any()))))
+  2 = 1 + (2 + (3 + 4))
 }