Checker: Add base of checker list view.

src/Checker/Study.py

@@ -0,0 +1,36 @@
+# -*- coding: utf-8 -*-
+
+from PyQt5.QtCore import QCoreApplication
+
+from Checker.Checker import AbstractModelChecker, STATUS
+
+_translate = QCoreApplication.translate
+
+
+class StudyNetworkReachChecker(AbstractModelChecker):
+    def __init__(self):
+        super(StudyNetworkReachChecker, self).__init__()
+
+        self._name = _translate("Checker", "Study network reach checker")
+        self._description = _translate("Checker", "Check if exists at least one reach for study")
+
+    def run(self, study):
+        if study is None:
+            self._status = STATUS.ERROR
+            self._summary = "invalid_study"
+            return False
+
+        river = study.river
+        if river is None:
+            self._status = STATUS.ERROR
+            self._summary = "no_river_found"
+            return False
+
+        if len(river.edges()) == 0:
+            self._status = STATUS.ERROR
+            self._summary = "no_reach_defined"
+            return False
+
+        self._summary = "ok"
+        self._status = STATUS.OK
+        return True