from unittest.runner import TextTestResult
from django.test.runner import DiscoverRunner

import time

class TimeLoggingTestRunner(DiscoverRunner):
    def __init__(self, slow_test_threshold=0.0, *args, **kwargs):
        self.slow_test_threshold = slow_test_threshold
        return super().__init__(
            resultclass=TimeLoggingTestResult,
            *args,
            **kwargs,
        )
    def run(self, test):
        result = super().run(test)
        self.stream.writeln(
            "nSlow Tests (>{:.03}s):".format(
                self.slow_test_threshold))
        for name, elapsed in result.getTestTimings():
            if elapsed > self.slow_test_threshold:
                self.stream.writeln(
                    "({:.03}s) {}".format(
                        elapsed, name))
        return result

    def get_resultclass(self):
        return TimeLoggingTestResult

class TimeLoggingTestResult(TextTestResult):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.test_timings = []
    def startTest(self, test):
        self._test_started_at = time.time()
        super().startTest(test)
    def addSuccess(self, test):
        elapsed = time.time() - self._test_started_at
        name = self.getDescription(test)
        self.test_timings.append((name, elapsed))
        super().addSuccess(test)
    def getTestTimings(self):
        return self.test_timings

TEST_RUNNER = 'core.utils.test_runner.runner.TimeLoggingTestRunner'