chore: improve create_command_partials runtime by not calling subprocess several times

Author: xmatthias

build_helpers/create_command_partials.py

@@ -1,5 +1,7 @@
+import os
 import subprocess  # noqa: S404, RUF100
 import sys
+from io import StringIO
 from pathlib import Path
 
 
@@ -8,7 +10,20 @@ def _write_partial_file(filename: str, content: str):
         f.write(f"``` output\n{content}\n```\n")
 
 
+def _get_help_output(parser) -> str:
+    """Capture the help output from a parser."""
+    output = StringIO()
+    parser.print_help(file=output)
+    return output.getvalue()
+
+
 def extract_command_partials():
+    # Set terminal width to 80 columns for consistent output formatting
+    os.environ["COLUMNS"] = "80"
+
+    # Import Arguments here to avoid circular imports and ensure COLUMNS is set
+    from freqtrade.commands.arguments import Arguments
+
     subcommands = [
         "trade",
         "create-userdir",
@@ -46,16 +61,35 @@ def extract_command_partials():
         "recursive-analysis",
     ]
 
-    result = subprocess.run(["freqtrade", "--help"], capture_output=True, text=True)
+    # Build the Arguments class to get the parser with all subcommands
+    args = Arguments(None)
+    args._build_subcommands()
 
-    _write_partial_file("docs/commands/main.md", result.stdout)
+    # Get main help output
+    main_help = _get_help_output(args.parser)
+    _write_partial_file("docs/commands/main.md", main_help)
+
+    # Get subparsers from the main parser
+    # The subparsers are stored in _subparsers._group_actions[0].choices
+    subparsers_action = None
+    for action in args.parser._subparsers._group_actions:
+        if hasattr(action, "choices"):
+            subparsers_action = action
+            break
+
+    if subparsers_action is None:
+        raise RuntimeError("Could not find subparsers in the main parser")
 
     for command in subcommands:
         print(f"Running for {command}")
-        result = subprocess.run(["freqtrade", command, "--help"], capture_output=True, text=True)
-
-        _write_partial_file(f"docs/commands/{command}.md", result.stdout)
+        if command in subparsers_action.choices:
+            subparser = subparsers_action.choices[command]
+            help_output = _get_help_output(subparser)
+            _write_partial_file(f"docs/commands/{command}.md", help_output)
+        else:
+            print(f"  Warning: subcommand '{command}' not found in parser")
 
+    # freqtrade-client still uses subprocess as requested
     print("Running for freqtrade-client")
     result_client = subprocess.run(["freqtrade-client", "--show"], capture_output=True, text=True)