Add replace_in_file command (#4565)

Resubmission of #3643

---------

Co-authored-by: Reinier van der Leer <github@pwuts.nl>

autogpt/commands/file_operations.py

@@ -4,6 +4,7 @@ from __future__ import annotations
 import hashlib
 import os
 import os.path
+import re
 from typing import TYPE_CHECKING, Generator, Literal
 
 import requests
@@ -224,6 +225,68 @@ def write_to_file(filename: str, text: str, config: Config) -> str:
         return f"Error: {err}"
 
 
+@command(
+    "replace_in_file",
+    "Replace text or code in a file",
+    '"filename": "<filename>", '
+    '"old_text": "<old_text>", "new_text": "<new_text>", '
+    '"occurrence_index": "<occurrence_index>"',
+)
+def replace_in_file(
+    filename: str, old_text: str, new_text: str, config: Config, occurrence_index=None
+):
+    """Update a file by replacing one or all occurrences of old_text with new_text using Python's built-in string
+    manipulation and regular expression modules for cross-platform file editing similar to sed and awk.
+
+    Args:
+        filename (str): The name of the file
+        old_text (str): String to be replaced. \n will be stripped from the end.
+        new_text (str): New string. \n will be stripped from the end.
+        occurrence_index (int): Optional index of the occurrence to replace. If None, all occurrences will be replaced.
+
+    Returns:
+        str: A message indicating whether the file was updated successfully or if there were no matches found for old_text
+        in the file.
+
+    Raises:
+        Exception: If there was an error updating the file.
+    """
+    try:
+        with open(filename, "r", encoding="utf-8") as f:
+            content = f.read()
+
+        old_text = old_text.rstrip("\n")
+        new_text = new_text.rstrip("\n")
+
+        if occurrence_index is None:
+            new_content = content.replace(old_text, new_text)
+        else:
+            matches = list(re.finditer(re.escape(old_text), content))
+            if not matches:
+                return f"No matches found for {old_text} in {filename}"
+
+            if int(occurrence_index) >= len(matches):
+                return f"Occurrence index {occurrence_index} is out of range for {old_text} in {filename}"
+
+            match = matches[int(occurrence_index)]
+            start, end = match.start(), match.end()
+            new_content = content[:start] + new_text + content[end:]
+
+        if content == new_content:
+            return f"No matches found for {old_text} in {filename}"
+
+        with open(filename, "w", encoding="utf-8") as f:
+            f.write(new_content)
+
+        with open(filename, "r", encoding="utf-8") as f:
+            checksum = text_checksum(f.read())
+        log_operation("update", filename, config, checksum=checksum)
+
+        return f"File {filename} updated successfully."
+    except Exception as e:
+        return "Error: " + str(e)
+
+
 @command(
     "append_to_file", "Append to file", '"filename": "<filename>", "text": "<text>"'
 )

tests/unit/test_file_operations.py

@@ -268,6 +268,53 @@ def test_write_file_succeeds_if_content_different(
     assert result == "File written to successfully."
 
 
+# Update file testing
+def test_replace_in_file_all_occurrences(test_file, test_file_path, config):
+    old_content = "This is a test file.\n we test file here\na test is needed"
+    expected_content = (
+        "This is a update file.\n we update file here\na update is needed"
+    )
+    test_file.write(old_content)
+    test_file.close()
+    file_ops.replace_in_file(test_file_path, "test", "update", config)
+    with open(test_file_path) as f:
+        new_content = f.read()
+    print(new_content)
+    print(expected_content)
+    assert new_content == expected_content
+
+
+def test_replace_in_file_one_occurrence(test_file, test_file_path, config):
+    old_content = "This is a test file.\n we test file here\na test is needed"
+    expected_content = "This is a test file.\n we update file here\na test is needed"
+    test_file.write(old_content)
+    test_file.close()
+    file_ops.replace_in_file(
+        test_file_path, "test", "update", config, occurrence_index=1
+    )
+    with open(test_file_path) as f:
+        new_content = f.read()
+
+    assert new_content == expected_content
+
+
+def test_replace_in_file_multiline_old_text(test_file, test_file_path, config):
+    old_content = "This is a multi_line\ntest for testing\nhow well this function\nworks when the input\nis multi-lined"
+    expected_content = "This is a multi_line\nfile. succeeded test\nis multi-lined"
+    test_file.write(old_content)
+    test_file.close()
+    file_ops.replace_in_file(
+        test_file_path,
+        "\ntest for testing\nhow well this function\nworks when the input\n",
+        "\nfile. succeeded test\n",
+        config,
+    )
+    with open(test_file_path) as f:
+        new_content = f.read()
+
+    assert new_content == expected_content
+
+
 def test_append_to_file(test_nested_file: Path, config):
     append_text = "This is appended text.\n"
     file_ops.write_to_file(test_nested_file, append_text, config)