[time] Fix RTC is_valid() rejecting valid times after day_of_year cleanup (#15763)

tests/components/time/is_valid.cpp

@@ -0,0 +1,72 @@
+// Regression tests for ESPTime::is_valid() optional checks.
+//
+// The RTC components (ds1307, bm8563, pcf85063, pcf8563, rx8130) read date/time
+// fields from hardware but do not populate day_of_year. They call
+// recalc_timestamp_utc(false) -- which skips day_of_year -- and then is_valid().
+// These tests ensure the is_valid() overload can skip day_of_year validation so
+// RTCs don't log "Invalid RTC time, not syncing to system clock." for valid times.
+
+#include <gtest/gtest.h>
+#include "esphome/core/time.h"
+
+namespace esphome::testing {
+
+// Build an ESPTime that mirrors what the RTC components construct: all fields
+// populated from hardware except day_of_year (left zero-initialized).
+static ESPTime make_rtc_like_time() {
+  ESPTime t{};
+  t.second = 30;
+  t.minute = 15;
+  t.hour = 12;
+  t.day_of_week = 4;  // thursday
+  t.day_of_month = 15;
+  t.month = 4;
+  t.year = 2026;
+  // day_of_year intentionally left at 0 -- RTCs don't compute it.
+  return t;
+}
+
+TEST(ESPTimeIsValid, DefaultRejectsZeroDayOfYear) {
+  // Default is_valid() checks day_of_year; zero-init is out of range.
+  ESPTime t = make_rtc_like_time();
+  EXPECT_FALSE(t.is_valid());
+}
+
+TEST(ESPTimeIsValid, SkipDayOfYearAcceptsRTCLikeTime) {
+  // RTC code path: skip day_of_year validation.
+  ESPTime t = make_rtc_like_time();
+  EXPECT_TRUE(t.is_valid(/*check_day_of_week=*/true, /*check_day_of_year=*/false));
+}
+
+TEST(ESPTimeIsValid, SkipDayOfYearStillRejectsOutOfRangeFields) {
+  ESPTime t = make_rtc_like_time();
+  t.hour = 25;
+  EXPECT_FALSE(t.is_valid(/*check_day_of_week=*/true, /*check_day_of_year=*/false));
+}
+
+TEST(ESPTimeIsValid, SkipDayOfYearStillRejectsYearBefore2019) {
+  ESPTime t = make_rtc_like_time();
+  t.year = 2000;
+  EXPECT_FALSE(t.is_valid(/*check_day_of_week=*/true, /*check_day_of_year=*/false));
+}
+
+TEST(ESPTimeIsValid, SkipBothDayChecksAcceptsGPSLikeTime) {
+  // GPS path (gps_time.cpp) populates neither day_of_week nor day_of_year.
+  ESPTime t{};
+  t.second = 30;
+  t.minute = 15;
+  t.hour = 12;
+  t.day_of_month = 15;
+  t.month = 4;
+  t.year = 2026;
+  EXPECT_TRUE(t.is_valid(/*check_day_of_week=*/false, /*check_day_of_year=*/false));
+  EXPECT_FALSE(t.is_valid());  // default still rejects
+}
+
+TEST(ESPTimeIsValid, FullyPopulatedAcceptsWithDefaults) {
+  ESPTime t = make_rtc_like_time();
+  t.day_of_year = 105;
+  EXPECT_TRUE(t.is_valid());
+}
+
+}  // namespace esphome::testing