Method replace_file_lines

ms_agent/tools/filesystem_tool.py:554–633

Replace specific line ranges in a file. Args: path(str): The relative file path to modify, a prefix dir will be automatically concatenated. content(str): The new content to insert/replace start_line(int): Start line number (1-based, inclusive). Use 0 to i

(self,
                                 path: str,
                                 content: str,
                                 start_line: int,
                                 end_line: int = None)

            return f'Replace content in file <{path}> failed, error: ' + str(e)

    async def replace_file_lines(self,
                                 path: str,
                                 content: str,
                                 start_line: int,
                                 end_line: int = None):
        """Replace specific line ranges in a file.

        Args:
            path(str): The relative file path to modify, a prefix dir will be automatically concatenated.
            content(str): The new content to insert/replace
            start_line(int): Start line number (1-based, inclusive). Use 0 to insert at beginning, -1 to append at end
            end_line(int): End line number (1-based, inclusive). Optional for start_line=0 or -1

        Returns:
            Success or error message.
        """
        try:
            target_path_real = self.get_real_path(path)
            if target_path_real is None:
                return f'<{path}> is out of the valid project path: {self.output_dir}'
            file_path = target_path_real
            # Read existing file content
            if os.path.exists(file_path):
                with open(file_path, 'r', encoding='utf-8') as f:
                    lines = f.readlines()
            else:
                # If file doesn't exist, create it
                dirname = os.path.dirname(file_path)
                if dirname:
                    os.makedirs(dirname, exist_ok=True)
                lines = []

            total_lines = len(lines)

            # Ensure content ends with newline if it doesn't already
            if content and not content.endswith('\n'):
                content += '\n'

            # Handle special cases
            if start_line == 0:
                # Insert at beginning
                new_lines = [content] + lines
                operation = 'Inserted at beginning'
            elif start_line == -1:
                # Append at end
                new_lines = lines + [content]
                operation = 'Appended at end'
            else:
                # Replace range (1-based, inclusive)
                if end_line is None:
                    return 'Error: end_line is required when start_line is not 0 or -1'

                if start_line < 1 or start_line > total_lines + 1:
                    return f'Error: start_line {start_line} is out of range (file has {total_lines} lines)'

                if end_line < start_line:
                    return f'Error: end_line {end_line} must be >= start_line {start_line}'