From 834ad955e382bd25524af696ae450662719d663b Mon Sep 17 00:00:00 2001
From: "Kristijan \"Fremen\" Velkovski" <me@krisfremen.com>
Date: Wed, 6 Nov 2024 00:13:19 -0600
Subject: [PATCH] Add FORMAT_RFC3339_STRICT with a T separator.

---
 arrow/__init__.py       | 2 ++
 arrow/formatter.py      | 1 +
 tests/test_formatter.py | 7 +++++++
 3 files changed, 10 insertions(+)

diff --git a/arrow/__init__.py b/arrow/__init__.py
index bc5970970..9232b379c 100644
--- a/arrow/__init__.py
+++ b/arrow/__init__.py
@@ -11,6 +11,7 @@
     FORMAT_RFC1123,
     FORMAT_RFC2822,
     FORMAT_RFC3339,
+    FORMAT_RFC3339_STRICT,
     FORMAT_RSS,
     FORMAT_W3C,
 )
@@ -33,6 +34,7 @@
     "FORMAT_RFC1123",
     "FORMAT_RFC2822",
     "FORMAT_RFC3339",
+    "FORMAT_RFC3339_STRICT",
     "FORMAT_RSS",
     "FORMAT_W3C",
     "ParserError",
diff --git a/arrow/formatter.py b/arrow/formatter.py
index 8cd61e908..6634545f0 100644
--- a/arrow/formatter.py
+++ b/arrow/formatter.py
@@ -17,6 +17,7 @@
 FORMAT_RFC1123: Final[str] = "ddd, DD MMM YYYY HH:mm:ss Z"
 FORMAT_RFC2822: Final[str] = "ddd, DD MMM YYYY HH:mm:ss Z"
 FORMAT_RFC3339: Final[str] = "YYYY-MM-DD HH:mm:ssZZ"
+FORMAT_RFC3339_STRICT: Final[str] = "YYYY-MM-DDTHH:mm:ssZZ"
 FORMAT_RSS: Final[str] = "ddd, DD MMM YYYY HH:mm:ss Z"
 FORMAT_W3C: Final[str] = "YYYY-MM-DD HH:mm:ssZZ"
 
diff --git a/tests/test_formatter.py b/tests/test_formatter.py
index 36e15d9fc..0b514ad9c 100644
--- a/tests/test_formatter.py
+++ b/tests/test_formatter.py
@@ -13,6 +13,7 @@
     FORMAT_RFC1123,
     FORMAT_RFC2822,
     FORMAT_RFC3339,
+    FORMAT_RFC3339_STRICT,
     FORMAT_RSS,
     FORMAT_W3C,
 )
@@ -254,6 +255,12 @@ def test_rfc3339(self):
             == "1975-12-25 14:15:16-05:00"
         )
 
+    def test_rfc3339_strict(self):
+        assert (
+            self.formatter.format(self.datetime, FORMAT_RFC3339_STRICT)
+            == "1975-12-25T14:15:16-05:00"
+        )
+
     def test_rss(self):
         assert (
             self.formatter.format(self.datetime, FORMAT_RSS)