Concepts for elliptic cureve and misc. updates.

python/ql/lib/semmle/python/Files.qll

@@ -368,3 +368,40 @@ class EncodingError extends SyntaxError {
 
   override string toString() { result = "Encoding Error" }
 }
+
+
+
+/**
+ * A dummy location which is used when something doesn't have a location in
+ * the source code but needs to have a `Location` associated with it. There
+ * may be several distinct kinds of unknown locations. For example: one for
+ * expressions, one for statements and one for other program elements.
+ */
+class UnknownLocation extends Location {
+  UnknownLocation() { this.getFile().getAbsolutePath() = "" }
+}
+
+/**
+ * A dummy location which is used when something doesn't have a location in
+ * the source code but needs to have a `Location` associated with it.
+ */
+class UnknownDefaultLocation extends UnknownLocation {
+  UnknownDefaultLocation() { locations_default(this, _, 0, 0, 0, 0) }
+}
+
+/**
+ * A dummy location which is used when an expression doesn't have a
+ * location in the source code but needs to have a `Location` associated
+ * with it.
+ */
+class UnknownExprLocation extends UnknownLocation {
+  UnknownExprLocation() { locations_default(this, _, 0, 0, 0, 0) }
+}
+
+/**
+ * A dummy location which is used when a statement doesn't have a location
+ * in the source code but needs to have a `Location` associated with it.
+ */
+class UnknownStmtLocation extends UnknownLocation {
+  UnknownStmtLocation() { locations_default(this, _, 0, 0, 0, 0) }
+}