From a4293398b7d633bb93e613ff819057e00f96cdb0 Mon Sep 17 00:00:00 2001
From: Jesse Bannon <jbann1994@gmail.com>
Date: Sun, 4 May 2025 18:19:32 -0700
Subject: [PATCH] [FEATURE] Add `join` and `strip` string functions to
 scripting (#1218)

---
 .../scripting/scripting_functions.rst         | 35 +++++++++++++++++
 .../script/functions/string_functions.py      | 38 +++++++++++++++++++
 .../script/functions/test_string_functions.py | 20 ++++++++++
 3 files changed, 93 insertions(+)

diff --git a/docs/source/config_reference/scripting/scripting_functions.rst b/docs/source/config_reference/scripting/scripting_functions.rst
index cc42c52c..61076fa7 100644
--- a/docs/source/config_reference/scripting/scripting_functions.rst
+++ b/docs/source/config_reference/scripting/scripting_functions.rst
@@ -660,6 +660,24 @@ contains_any
 :description:
     Returns true if any element in ``contains_array`` is in ``string``. False otherwise.
 
+join
+~~~~
+:spec: ``join(separator: String, array: Array) -> String``
+
+:description:
+    Join all elements in the array together as a string, and insert the
+    separator between them.
+
+:usage:
+
+.. code-block:: python
+
+   {
+     %join( ", ", ["item1", "item2"] )
+   }
+
+   # "item1, item2"
+
 lower
 ~~~~~
 :spec: ``lower(string: String) -> String``
@@ -710,6 +728,23 @@ string
 :description:
   Cast to String.
 
+strip
+~~~~~
+:spec: ``strip(string: String) -> String``
+
+:description:
+    Strip a string of all its whitespace at the beginning and end.
+
+:usage:
+
+.. code-block:: python
+
+   {
+     %trim(" delete the outer! ")
+   }
+
+   # "delete the outer!"
+
 titlecase
 ~~~~~~~~~
 :spec: ``titlecase(string: String) -> String``
diff --git a/src/ytdl_sub/script/functions/string_functions.py b/src/ytdl_sub/script/functions/string_functions.py
index e9af7a54..43ff87a5 100644
--- a/src/ytdl_sub/script/functions/string_functions.py
+++ b/src/ytdl_sub/script/functions/string_functions.py
@@ -176,3 +176,41 @@ class StringFunctions:
            # World
         """
         return String(string.value.encode("utf-8").decode("unicode_escape"))
+
+    @staticmethod
+    def join(separator: String, array: Array) -> String:
+        """
+        :description:
+            Join all elements in the array together as a string, and insert the
+            separator between them.
+
+        :usage:
+
+        .. code-block:: python
+
+           {
+             %join( ", ", ["item1", "item2"] )
+           }
+
+           # "item1, item2"
+        """
+
+        return String(separator.value.join(str(val) for val in array.value))
+
+    @staticmethod
+    def strip(string: String) -> String:
+        """
+        :description:
+            Strip a string of all its whitespace at the beginning and end.
+
+        :usage:
+
+        .. code-block:: python
+
+           {
+             %trim(" delete the outer! ")
+           }
+
+           # "delete the outer!"
+        """
+        return String(string.value.strip())
diff --git a/tests/unit/script/functions/test_string_functions.py b/tests/unit/script/functions/test_string_functions.py
index f5c85741..bc5bfc32 100644
--- a/tests/unit/script/functions/test_string_functions.py
+++ b/tests/unit/script/functions/test_string_functions.py
@@ -152,3 +152,23 @@ class TestNumericFunctions:
             output = single_variable_output(f"{{%split('{input_string}', {split})}}")
 
         assert output == expected_output
+
+    @pytest.mark.parametrize(
+        "value, expected_output",
+        [
+            ("['a', 'b', 'c']", "a, b, c"),
+            ("['nope', [], {}]", "nope, [], {}"),
+            ("['a', 1, 3.14, True]", "a, 1, 3.14, true"),
+        ],
+    )
+    def test_join(self, value, expected_output):
+        output = single_variable_output(f"{{%join(', ', {value})}}")
+        assert output == expected_output
+
+    @pytest.mark.parametrize(
+        "value, expected_output",
+        [(" delete outer ", "delete outer"), (" delete me\n\n", "delete me")],
+    )
+    def test_strip(self, value, expected_output):
+        output = single_variable_output(f"{{%strip('{value}')}}")
+        assert output == expected_output