diff --git a/tests/unit/script/functions/test_conditional_functions.py b/tests/unit/script/functions/test_conditional_functions.py
index eff73214..d2078a80 100644
--- a/tests/unit/script/functions/test_conditional_functions.py
+++ b/tests/unit/script/functions/test_conditional_functions.py
@@ -3,6 +3,9 @@ import re
 import pytest
 from unit.script.conftest import single_variable_output
 
+from ytdl_sub.script.script import Script
+from ytdl_sub.script.types.syntax_tree import SyntaxTree
+from ytdl_sub.script.types.variable import Variable
 from ytdl_sub.script.utils.exceptions import FunctionRuntimeException
 
 
@@ -135,3 +138,29 @@ class TestConditionalFunction:
     ):
         output = single_variable_output(function_str)
         assert output == expected_output
+
+    def test_if_partial_resolve(self):
+        assert (
+            Script(
+                {
+                    "aa": "a",
+                    "bb": "unresolvable!",
+                    "cc": "{%if( true, aa, bb )}",
+                }
+            )
+            .resolve_partial(unresolvable={"bb"})
+            .get("cc")
+            .native
+            == "a"
+        )
+
+    def test_if_partial_resolve_unresolved(self):
+        assert Script(
+            {
+                "aa": "a",
+                "bb": "unresolvable!",
+                "cc": "{%if( false, aa, bb )}",
+            }
+        ).resolve_partial(unresolvable={"bb"}).definition_of("cc") == SyntaxTree(
+            ast=[Variable("bb")]
+        )
diff --git a/tests/unit/script/types/test_array.py b/tests/unit/script/types/test_array.py
index f816b1bd..312ec325 100644
--- a/tests/unit/script/types/test_array.py
+++ b/tests/unit/script/types/test_array.py
@@ -10,6 +10,8 @@ from ytdl_sub.script.script_output import ScriptOutput
 from ytdl_sub.script.types.array import Array
 from ytdl_sub.script.types.resolvable import Float
 from ytdl_sub.script.types.resolvable import String
+from ytdl_sub.script.types.syntax_tree import SyntaxTree
+from ytdl_sub.script.types.variable import Variable
 from ytdl_sub.script.utils.exceptions import InvalidSyntaxException
 
 
@@ -117,3 +119,29 @@ class TestArray:
         ).resolve() == ScriptOutput(
             {"aa": String("a"), "bb": String("b"), "cc": String('return ["a", "b"]')}
         )
+
+    def test_partial_resolve(self):
+        assert (
+            Script(
+                {
+                    "aa": "a",
+                    "bb": "unresolvable!",
+                    "cc": "{%array_at( [aa, bb], 0 )}",
+                }
+            )
+            .resolve_partial(unresolvable={"bb"})
+            .get("cc")
+            .native
+            == "a"
+        )
+
+    def test_partial_resolve_unresolved(self):
+        assert Script(
+            {
+                "aa": "a",
+                "bb": "unresolvable!",
+                "cc": "{%array_at( [aa, bb], 1 )}",
+            }
+        ).resolve_partial(unresolvable={"bb"}).definition_of("cc") == SyntaxTree(
+            ast=[Variable("bb")]
+        )
diff --git a/tests/unit/script/types/test_custom_function.py b/tests/unit/script/types/test_custom_function.py
index 61096cc3..17919cc0 100644
--- a/tests/unit/script/types/test_custom_function.py
+++ b/tests/unit/script/types/test_custom_function.py
@@ -5,7 +5,9 @@ import pytest
 from ytdl_sub.script.parser import CUSTOM_FUNCTION_ARGUMENTS_ONLY_ARGS
 from ytdl_sub.script.script import Script
 from ytdl_sub.script.script_output import ScriptOutput
+from ytdl_sub.script.types.function import CustomFunction
 from ytdl_sub.script.types.resolvable import Integer
+from ytdl_sub.script.types.syntax_tree import SyntaxTree
 from ytdl_sub.script.utils.exceptions import CycleDetected
 from ytdl_sub.script.utils.exceptions import FunctionDoesNotExist
 from ytdl_sub.script.utils.exceptions import InvalidCustomFunctionArgumentName
@@ -251,3 +253,30 @@ class TestCustomFunction:
                     "output": "{%mul(%func1(1), 1)}",
                 }
             )
+
+    def test_partial_resolve_custom_functions_any_order_via_init(self):
+        assert (
+            Script(
+                {
+                    "%custom_cubed": "{%mul(%custom_square($0),$0)}",
+                    "%custom_square": "{%mul($0, $0)}",
+                    "output": "{%custom_cubed(3)}",
+                }
+            )
+            .resolve_partial()
+            .get("output")
+            .native
+            == 27
+        )
+
+    def test_partial_resolve_unresolved(self):
+        assert Script(
+            {
+                "aa": "nope",
+                "%custom_cubed": "{%mul(%custom_square($0),$0)}",
+                "%custom_square": "{%mul($0, aa)}",
+                "output": "{%custom_cubed(3)}",
+            }
+        ).resolve_partial(unresolvable={"aa"}).definition_of("output") == SyntaxTree(
+            ast=[CustomFunction(name="custom_cubed", args=[Integer(3)])]
+        )
diff --git a/tests/unit/script/types/test_lambda_function.py b/tests/unit/script/types/test_lambda_function.py
index cd054811..0474a1d3 100644
--- a/tests/unit/script/types/test_lambda_function.py
+++ b/tests/unit/script/types/test_lambda_function.py
@@ -177,3 +177,20 @@ class TestLambdaFunctionIncompatibleNumArguments:
             match=re.escape("Cycle detected within these variables: two -> %times_two -> two"),
         ):
             Script({"%times_two": "{%mul($0, two)}", "two": "{%times_two(2)}"})
+
+    def test_partial_resolve_nested_lambda_custom_functions_within_custom_functions(self):
+        assert (
+            Script(
+                {
+                    "%nest4": "{%mul($0, 2)}",
+                    "%nest3": "{%array_at(%array_apply([$0], %nest4), 0)}",
+                    "%nest2": "{%array_at(%array_apply([$0], %nest3), 0)}",
+                    "%nest1": "{%array_at(%array_apply([$0], %nest2), 0)}",
+                    "output": "{%array_at(%array_apply([2], %nest1), 0)}",
+                }
+            )
+            .resolve_partial()
+            .get("output")
+            .native
+            == 4
+        )