Add leading zero to log file date/time (#1925)

## Description

WAS: Logs did not have a leading zero, meaning that alphabetical and
temporal sort were not the same

IS: Logs now have leading zeros added. This means that alphabetical sort
works properly.

## Meta

Merge checklist:
- [x] Pull Request title is [short, imperative
summary](https://cbea.ms/git-commit/) of proposed changes
- [x] The description documents the _what_ and _why_
- [ ] If this PR changes behavior or adds a feature, user documentation
is updated
- [ ] If this PR touches photon-serde, all messages have been
regenerated and hashes have not changed unexpectedly
- [ ] If this PR touches configuration, this is backwards compatible
with settings back to v2024.3.1
- [ ] If this PR touches pipeline settings or anything related to data
exchange, the frontend typing is updated
- [ ] If this PR addresses a bug, a regression test for it is added

---------

Co-authored-by: Craig Schardt <crschardt@fastem.com>

docs/source/docs/troubleshooting/logging.md

@@ -28,7 +28,7 @@ Robot mode transitions are also recorded in program logs. These transition messa
 
 If the robot is connected to the FMS at an event, we will additionally print out:
 - Event name
-- Match type
+- Match type and number
 - Driver station position
 
 

photon-core/src/main/java/org/photonvision/common/configuration/PathManager.java

@@ -53,9 +53,9 @@ public class PathManager {
 
     public static final String LOG_PREFIX = "photonvision-";
     public static final String LOG_EXT = ".log";
-    public static final String LOG_DATE_TIME_FORMAT = "yyyy-M-d_hh-mm-ss";
+    public static final String LOG_DATE_TIME_FORMAT = "yyyy-MM-dd_HH-mm-ss";
 
-    public String taToLogFname(TemporalAccessor date) {
+    public static String taToLogFname(TemporalAccessor date) {
         var dateString = DateTimeFormatter.ofPattern(LOG_DATE_TIME_FORMAT).format(date);
         return LOG_PREFIX + dateString + LOG_EXT;
     }

photon-core/src/test/java/org/photonvision/common/configuration/PathManagerTest.java

@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) Photon Vision.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.photonvision.common.configuration;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.time.LocalDateTime;
+import java.time.Month;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+import org.junit.jupiter.api.Test;
+
+public class PathManagerTest {
+    @Test
+    public void testNamingFormat_LeadingZeros_And24HourUTC() {
+        // GIVEN: a LocalDateTime with single-digit month, day, hour, minute, second
+        LocalDateTime dt = LocalDateTime.of(2024, 1, 2, 3, 4, 5);
+
+        // WHEN: taToLogFname is called
+        String fname = PathManager.taToLogFname(dt);
+
+        // THEN: the returned name has leading zeros in all date and time parts
+        assertTrue(
+                fname.matches("^photonvision-2024-01-02_03-04-05\\.log$"),
+                "Filename should match the expected pattern with leading zeros");
+
+        // THEN: time is in 24-hour format (03 not 03AM or 3PM), already shown implicitly
+        assertTrue(fname.contains("_03-04-05"), "Time should be in 24-hour format with leading zeros");
+    }
+
+    @Test
+    public void testNamingFormat_OtherDate_CheckPattern() {
+        // GIVEN: another date and time
+        LocalDateTime dt = LocalDateTime.of(2023, 12, 31, 23, 59, 59);
+
+        // WHEN: taToLogFname is called
+        String fname = PathManager.taToLogFname(dt);
+
+        // THEN: the returned name correctly formats the entire timestamp
+        assertEquals("photonvision-2023-12-31_23-59-59.log", fname);
+    }
+
+    @Test
+    public void testNamingFormat_WithZonedDateTime_ConvertsToUTC() {
+        // GIVEN: a UTC ZonedDateTime at 7:08:09 on June 3, 2024
+        ZonedDateTime utcDateTime =
+                ZonedDateTime.of(2024, Month.JUNE.getValue(), 3, 7, 8, 9, 0, ZoneId.of("UTC"));
+
+        // WHEN: taToLogFname is called
+        String fname = PathManager.taToLogFname(utcDateTime);
+
+        // THEN: it is formatted in UTC, with leading zeros, 24-hour
+        assertEquals("photonvision-2024-06-03_07-08-09.log", fname);
+    }
+
+    @Test
+    public void testNamingFormat_WithNonUtcZoneTime_FormatsActualFieldsNotConverted() {
+        // GIVEN: a ZonedDateTime for 20:17:16 America/New_York (should use the provided fields, not
+        // convert to UTC)
+        ZonedDateTime nyTime =
+                ZonedDateTime.of(2024, 6, 3, 20, 17, 16, 0, ZoneId.of("America/New_York"));
+
+        // WHEN: taToLogFname is called
+        String fname = PathManager.taToLogFname(nyTime);
+
+        // THEN: asserts that fields from the zoned time are respected as is
+        assertEquals("photonvision-2024-06-03_20-17-16.log", fname);
+    }
+}