Add --cxml flag (#16)

Refs #15

---------

Co-authored-by: Simon Willison <swillison@gmail.com>

.gitignore

@@ -7,3 +7,4 @@ venv
 .pytest_cache
 *.egg-info
 .DS_Store
+build/

README.md

@@ -12,6 +12,7 @@ For background on this project see [Building files-to-prompt entirely using Clau
 ## Installation
 
 Install this tool using `pip`:
+
 ```bash
 pip install files-to-prompt
 ```
@@ -29,11 +30,13 @@ This will output the contents of every file, with each file preceded by its rela
 ### Options
 
 - `--include-hidden`: Include files and folders starting with `.` (hidden files and directories).
+
   ```bash
   files-to-prompt path/to/directory --include-hidden
   ```
 
 - `--ignore-gitignore`: Ignore `.gitignore` files and include all files.
+
   ```bash
   files-to-prompt path/to/directory --ignore-gitignore
   ```
@@ -101,6 +104,25 @@ Contents of file3.txt
 ---
 ```
 
+### XML Output
+
+Anthropic has provided [specific guidelines](https://docs.anthropic.com/claude/docs/long-context-window-tips) for optimally structuring prompts to take advantage of Claude's extended context window.
+
+To structure the output in this way, use the optional `--cxml` flag, which will produce output like this:
+
+```xml
+<documents>
+<document path="my_directory/file1.txt">
+Contents of file1.txt
+</document>
+
+<document path="my_directory/file2.txt">
+Contents of file2.txt
+</document>
+...
+</documents>
+```
+
 ## Development
 
 To contribute to this tool, first checkout the code. Then create a new virtual environment:
@@ -118,6 +140,7 @@ pip install -e '.[test]'
 ```
 
 To run the tests:
+
 ```bash
 pytest
 ```

files_to_prompt/cli.py

@@ -1,7 +1,8 @@
 import os
-import click
 from fnmatch import fnmatch
 
+import click
+
 
 def should_ignore(path, gitignore_rules):
     for rule in gitignore_rules:
@@ -22,18 +23,39 @@ def read_gitignore(path):
     return []
 
 
+def print_path(path, content, xml):
+    if xml:
+        print_as_xml(path, content)
+    else:
+        print_default(path, content)
+
+
+def print_default(path, content):
+    click.echo(path)
+    click.echo("---")
+    click.echo(content)
+    click.echo()
+    click.echo("---")
+
+
+def print_as_xml(path, content):
+    click.echo(f'<document path="{path}">')
+    click.echo(content)
+    click.echo("</document>")
+
+
 def process_path(
-    path, include_hidden, ignore_gitignore, gitignore_rules, ignore_patterns
+    path,
+    include_hidden,
+    ignore_gitignore,
+    gitignore_rules,
+    ignore_patterns,
+    claude_xml,
 ):
     if os.path.isfile(path):
         try:
             with open(path, "r") as f:
-                file_contents = f.read()
+                print_path(path, f.read(), claude_xml)
-            click.echo(path)
-            click.echo("---")
-            click.echo(file_contents)
-            click.echo()
-            click.echo("---")
         except UnicodeDecodeError:
             warning_message = f"Warning: Skipping file {path} due to UnicodeDecodeError"
             click.echo(click.style(warning_message, fg="red"), err=True)
@@ -63,17 +85,11 @@ def process_path(
                     if not any(fnmatch(f, pattern) for pattern in ignore_patterns)
                 ]
 
-            for file in files:
+            for file in sorted(files):
                 file_path = os.path.join(root, file)
                 try:
                     with open(file_path, "r") as f:
-                        file_contents = f.read()
+                        print_path(file_path, f.read(), claude_xml)
-
-                    click.echo(file_path)
-                    click.echo("---")
-                    click.echo(file_contents)
-                    click.echo()
-                    click.echo("---")
                 except UnicodeDecodeError:
                     warning_message = (
                         f"Warning: Skipping file {file_path} due to UnicodeDecodeError"
@@ -100,8 +116,15 @@ def process_path(
     default=[],
     help="List of patterns to ignore",
 )
+@click.option(
+    "claude_xml",
+    "-c",
+    "--cxml",
+    is_flag=True,
+    help="Output in XML-ish format suitable for Claude's long context window.",
+)
 @click.version_option()
-def cli(paths, include_hidden, ignore_gitignore, ignore_patterns):
+def cli(paths, include_hidden, ignore_gitignore, ignore_patterns, claude_xml):
     """
     Takes one or more paths to files or directories and outputs every file,
     recursively, each one preceded with its filename like this:
@@ -114,6 +137,19 @@ def cli(paths, include_hidden, ignore_gitignore, ignore_patterns):
     path/to/file2.py
     ---
     ...
+
+    If the `--cxml` flag is provided, the output will be structured as follows:
+
+    <documents>
+    <document path="path/to/file1.txt">
+    Contents of file1.txt
+    </document>
+
+    <document path="path/to/file2.txt">
+    Contents of file2.txt
+    </document>
+    ...
+    </documents>
     """
     gitignore_rules = []
     for path in paths:
@@ -121,6 +157,17 @@ def cli(paths, include_hidden, ignore_gitignore, ignore_patterns):
             raise click.BadArgumentUsage(f"Path does not exist: {path}")
         if not ignore_gitignore:
             gitignore_rules.extend(read_gitignore(os.path.dirname(path)))
+        if claude_xml and path == paths[0]:
+            click.echo("<documents>")
+
         process_path(
-            path, include_hidden, ignore_gitignore, gitignore_rules, ignore_patterns
+            path,
+            include_hidden,
+            ignore_gitignore,
+            gitignore_rules,
+            ignore_patterns,
+            claude_xml,
         )
+
+    if claude_xml:
+        click.echo("</documents>")

tests/test_files_to_prompt.py

@@ -1,5 +1,7 @@
 import os
+
 from click.testing import CliRunner
+
 from files_to_prompt.cli import cli
 
 
@@ -186,3 +188,56 @@ def test_binary_file_warning(tmpdir):
             "Warning: Skipping file test_dir/binary_file.bin due to UnicodeDecodeError"
             in stderr
         )
+
+
+def test_xml_format_dir(tmpdir):
+    runner = CliRunner()
+    with tmpdir.as_cwd():
+        os.makedirs("test_dir")
+        with open("test_dir/file1.txt", "w") as f:
+            f.write("Contents of file1")
+        with open("test_dir/file2.txt", "w") as f:
+            f.write("Contents of file2")
+
+        result = runner.invoke(cli, ["test_dir", "--cxml"])
+        assert result.exit_code == 0
+        actual = result.output
+        expected = """
+<documents>
+<document path="test_dir/file1.txt">
+Contents of file1
+</document>
+<document path="test_dir/file2.txt">
+Contents of file2
+</document>
+</documents>
+"""
+        assert expected.strip() == actual.strip()
+
+
+def test_cxml_format_multiple_paths(tmpdir):
+    runner = CliRunner()
+    with tmpdir.as_cwd():
+        os.makedirs("test_dir")
+        with open("test_dir/file1.txt", "w") as f:
+            f.write("Contents of file1")
+        with open("test_dir/file2.txt", "w") as f:
+            f.write("Contents of file2")
+
+        result = runner.invoke(
+            cli, ["test_dir/file1.txt", "test_dir/file2.txt", "--cxml"]
+        )
+
+        assert result.exit_code == 0
+        actual = result.output
+        expected = """
+<documents>
+<document path="test_dir/file1.txt">
+Contents of file1
+</document>
+<document path="test_dir/file2.txt">
+Contents of file2
+</document>
+</documents>
+"""
+        assert expected.strip() == actual.strip()