Swift: Fix missing QLDoc.

Author: geoffw0

swift/ql/lib/codeql/swift/security/SqlInjectionExtensions.qll

@@ -22,6 +22,10 @@ abstract class SqlInjectionBarrier extends DataFlow::Node { }
  * A unit class for adding additional flow steps.
  */
 class SqlInjectionAdditionalFlowStep extends Unit {
+  /**
+   * Holds if the step from `node1` to `node2` should be considered a flow
+   * step for paths related to SQL injection vulnerabilities.
+   */
   abstract predicate step(DataFlow::Node nodeFrom, DataFlow::Node nodeTo);
 }
 

swift/ql/lib/codeql/swift/security/UncontrolledFormatStringExtensions.qll

@@ -23,6 +23,10 @@ abstract class UncontrolledFormatStringBarrier extends DataFlow::Node { }
  * A unit class for adding additional flow steps.
  */
 class UncontrolledFormatStringAdditionalFlowStep extends Unit {
+  /**
+   * Holds if the step from `node1` to `node2` should be considered a flow
+   * step for paths related to uncontrolled format string vulnerabilities.
+   */
   abstract predicate step(DataFlow::Node nodeFrom, DataFlow::Node nodeTo);
 }
 

swift/ql/lib/codeql/swift/security/UnsafeJsEvalExtensions.qll

@@ -22,6 +22,10 @@ abstract class UnsafeJsEvalBarrier extends DataFlow::Node { }
  * A unit class for adding additional flow steps.
  */
 class UnsafeJsEvalAdditionalFlowStep extends Unit {
+  /**
+   * Holds if the step from `node1` to `node2` should be considered a flow
+   * step for paths related to javascript evaluation vulnerabilities.
+   */
   abstract predicate step(DataFlow::Node nodeFrom, DataFlow::Node nodeTo);
 }
 

swift/ql/lib/codeql/swift/security/UnsafeWebViewFetchExtensions.qll

@@ -27,6 +27,10 @@ abstract class UnsafeWebViewFetchBarrier extends DataFlow::Node { }
  * A unit class for adding additional flow steps.
  */
 class UnsafeWebViewFetchAdditionalFlowStep extends Unit {
+  /**
+   * Holds if the step from `node1` to `node2` should be considered a flow
+   * step for paths related to unsafe webview fetch vulnerabilities.
+   */
   abstract predicate step(DataFlow::Node nodeFrom, DataFlow::Node nodeTo);
 }
 

swift/ql/lib/codeql/swift/security/XXEExtensions.qll

@@ -14,11 +14,12 @@ abstract class XxeBarrier extends DataFlow::Node { }
 
 /**
  * A unit class for adding additional flow steps.
- *
- * Extend this class to add additional flow steps that should apply to paths related to
- * XML external entities (XXE) vulnerabilities.
  */
 class XxeAdditionalFlowStep extends Unit {
+  /**
+   * Holds if the step from `node1` to `node2` should be considered a flow
+   * step for paths related to XML external entities (XXE) vulnerabilities.
+   */
   abstract predicate step(DataFlow::Node n1, DataFlow::Node n2);
 }