chore: import upstream snapshot with attribution

tests/unittests/code_executors/test_code_execution_utils.py

@@ -0,0 +1,179 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import signal
+
+from google.adk.code_executors import code_execution_utils
+from google.genai import types
+
+
+def test_extract_code_and_truncate_content_basic():
+  """Tests basic code extraction and content truncation."""
+  content = types.Content(
+      role="model",
+      parts=[
+          types.Part(
+              text=(
+                  "Here is some code:\n```python\nx = 1\n```\nAnd some text"
+                  " after."
+              )
+          )
+      ],
+  )
+  delimiters = [("```python\n", "\n```")]
+  code = (
+      code_execution_utils.CodeExecutionUtils.extract_code_and_truncate_content(
+          content, delimiters
+      )
+  )
+  assert code == "x = 1"
+  assert len(content.parts) == 2
+  assert content.parts[0].text == "Here is some code:\n"
+  assert content.parts[1].executable_code.code == "x = 1"
+
+
+def test_extract_code_and_truncate_content_multiple_blocks():
+  """Tests that the first code block is extracted when multiple exist."""
+  content = types.Content(
+      role="model",
+      parts=[
+          types.Part(
+              text=(
+                  "First:\n"
+                  "```python\n"
+                  "x = 1\n"
+                  "```\n"
+                  "Second:\n"
+                  "```python\n"
+                  "y = 2\n"
+                  "```"
+              )
+          )
+      ],
+  )
+  delimiters = [("```python\n", "\n```")]
+  code = (
+      code_execution_utils.CodeExecutionUtils.extract_code_and_truncate_content(
+          content, delimiters
+      )
+  )
+  assert code == "x = 1"
+  assert len(content.parts) == 2
+  assert content.parts[0].text == "First:\n"
+  assert content.parts[1].executable_code.code == "x = 1"
+
+
+def test_extract_code_and_truncate_content_no_delimiter():
+  """Tests when no delimiters are found in the content."""
+  content = types.Content(
+      role="model",
+      parts=[types.Part(text="Just plain text without code.")],
+  )
+  delimiters = [("```python\n", "\n```")]
+  code = (
+      code_execution_utils.CodeExecutionUtils.extract_code_and_truncate_content(
+          content, delimiters
+      )
+  )
+  assert code is None
+  # Content should be unmodified.
+  assert len(content.parts) == 1
+  assert content.parts[0].text == "Just plain text without code."
+
+
+def test_extract_code_and_truncate_content_redos_vulnerability():
+  """Tests that a string that would cause ReDoS behaves reasonably."""
+  # Construct a long string that contains repeating patterns without matching delimiters.
+  # The old regex pattern would backtrack exponentially.
+  ticks = "`" * 3
+  long_invalid_payload = ticks + "python\n" + "x = 1\n" * 5000 + "not_matching"
+  content = types.Content(
+      role="model",
+      parts=[types.Part(text=long_invalid_payload)],
+  )
+  delimiters = [(ticks + "python\n", "\n" + ticks)]
+
+  def handler(_signum, _frame):
+    raise TimeoutError("Test timed out (possible ReDoS regression)")
+
+  signal.signal(signal.SIGALRM, handler)
+  signal.alarm(2)
+  try:
+    # If ReDoS vulnerability exists, this call will hang or take a very long time.
+    code = code_execution_utils.CodeExecutionUtils.extract_code_and_truncate_content(
+        content, delimiters
+    )
+  finally:
+    signal.alarm(0)
+  assert code is None
+
+
+def test_extract_code_and_truncate_content_multiple_delimiter_pairs():
+  """Tests code extraction when multiple different delimiter pairs are provided."""
+  ticks = "`" * 3
+  # Case 1: First delimiter pair matches first
+  content = types.Content(
+      role="model",
+      parts=[
+          types.Part(
+              text="Here is tool code:\n"
+              + ticks
+              + "tool_code\nx = 1\n"
+              + ticks
+              + "\nAnd python code:\n"
+              + ticks
+              + "python\ny = 2\n"
+              + ticks
+          )
+      ],
+  )
+  delimiters = [
+      (ticks + "tool_code\n", "\n" + ticks),
+      (ticks + "python\n", "\n" + ticks),
+  ]
+  code = (
+      code_execution_utils.CodeExecutionUtils.extract_code_and_truncate_content(
+          content, delimiters
+      )
+  )
+  assert code == "x = 1"
+  assert len(content.parts) == 2
+  assert content.parts[0].text == "Here is tool code:\n"
+  assert content.parts[1].executable_code.code == "x = 1"
+
+  # Case 2: Second delimiter pair matches first
+  content = types.Content(
+      role="model",
+      parts=[
+          types.Part(
+              text="Here is python code:\n"
+              + ticks
+              + "python\ny = 2\n"
+              + ticks
+              + "\nAnd tool code:\n"
+              + ticks
+              + "tool_code\nx = 1\n"
+              + ticks
+          )
+      ],
+  )
+  code = (
+      code_execution_utils.CodeExecutionUtils.extract_code_and_truncate_content(
+          content, delimiters
+      )
+  )
+  assert code == "y = 2"
+  assert len(content.parts) == 2
+  assert content.parts[0].text == "Here is python code:\n"
+  assert content.parts[1].executable_code.code == "y = 2"