add Diagnostics.qll

ql/src/codeql_ruby/Diagnostics.qll

@@ -0,0 +1,31 @@
+private import codeql.Locations
+
+/** A diagnostic emitted during extraction, such as a parse error */
+class Diagnostic extends @diagnostic {
+  /**
+   * Gets the numerical severity level associated with this diagnostic.
+   */
+  int getSeverity() { diagnostics(this, result, _, _, _, _) }
+
+  /** Gets the error code associated with this diagnostic, e.g. parse_error. */
+  string getTag() { diagnostics(this, _, result, _, _, _) }
+
+  /**
+   * Gets the error message text associated with this diagnostic.
+   */
+  string getMessage() { diagnostics(this, _, _, result, _, _) }
+
+  /**
+   * Gets the full error message text associated with this diagnostic.
+   */
+  string getFullMessage() { diagnostics(this, _, _, _, result, _) }
+
+  /** Gets the source location of this diagnostic. */
+  Location getLocation() { diagnostics(this, _, _, _, _, result) }
+
+  string toString() { result = this.getMessage() }
+}
+
+class ExtractionError extends Diagnostic {
+  ExtractionError() { this.getTag() = "parse_error" }
+}