feat(cli): add prefix-based command matching and autocomplete module

lean/commands/__init__.py

@@ -12,6 +12,7 @@
 # limitations under the License.
 
 from lean.commands.lean import lean
+from lean.commands.autocomplete import autocomplete, enable_autocomplete, disable_autocomplete
 from lean.commands.backtest import backtest
 from lean.commands.build import build
 from lean.commands.cloud import cloud
@@ -36,6 +37,9 @@
 from lean.commands.private_cloud import private_cloud
 
 lean.add_command(config)
+lean.add_command(autocomplete)
+lean.add_command(enable_autocomplete)
+lean.add_command(disable_autocomplete)
 lean.add_command(cloud)
 lean.add_command(data)
 lean.add_command(decrypt)

lean/commands/autocomplete.py

@@ -0,0 +1,269 @@
+# QUANTCONNECT.COM - Democratizing Finance, Empowering Individuals.
+# Lean CLI v1.0. Copyright 2021 QuantConnect Corporation.
+
+import os
+import subprocess
+from pathlib import Path
+from platform import system
+from click import group, argument, Choice, echo, option, command
+from lean.components.util.click_aliased_command_group import AliasedCommandGroup
+
+
+def get_all_commands(grp, path=''):
+    import click
+    res = []
+    if isinstance(grp, click.Group):
+        for name, sub in grp.commands.items():
+            full_path = (path + name).strip()
+            res.append(full_path)  # always add the command/group itself
+            if isinstance(sub, click.Group):
+                res.extend(get_all_commands(sub, path + name + ' '))  # drill into subcommands
+    return res
+
+
+def detect_shell() -> str:
+    """Auto-detect the current shell environment."""
+    if system() == 'Windows':
+        # On Windows, default to powershell
+        parent = os.environ.get('PSModulePath', '')
+        if parent:
+            return 'powershell'
+        return 'powershell'  # CMD falls back to powershell
+    else:
+        # Unix: check $SHELL env var
+        shell_path = os.environ.get('SHELL', '/bin/bash')
+        shell_name = Path(shell_path).name.lower()
+        if 'zsh' in shell_name:
+            return 'zsh'
+        elif 'fish' in shell_name:
+            return 'fish'
+        return 'bash'
+
+
+def get_powershell_script():
+    from lean.commands.lean import lean
+    commands_list = get_all_commands(lean)
+    commands_csv = ','.join(commands_list)
+    script = rf"""
+Register-ArgumentCompleter -Native -CommandName lean -ScriptBlock {{
+    param($wordToComplete, $commandAst, $cursorPosition)
+
+    $lean_commands = '{commands_csv}' -split ','
+
+    $cmdLine = $commandAst.ToString().TrimStart()
+    $cmdLine = $cmdLine -replace '^(lean)\s*', ''
+
+    if (-not $wordToComplete) {{
+        $prefix = $cmdLine
+    }} else {{
+        if ($cmdLine.EndsWith($wordToComplete)) {{
+            $prefix = $cmdLine.Substring(0, $cmdLine.Length - $wordToComplete.Length).TrimEnd()
+        }} else {{
+            $prefix = $cmdLine
+        }}
+    }}
+
+    $possible = @()
+    if (-not $prefix) {{
+        $possible = $lean_commands | Where-Object {{ $_ -notmatch ' ' }}
+    }} else {{
+        $possible = $lean_commands | Where-Object {{ $_.StartsWith($prefix + ' ') }} | ForEach-Object {{
+            $suffix = $_.Substring($prefix.Length + 1)
+            $suffix.Split(' ')[0]
+        }}
+    }}
+
+    $validPossible = $possible | Select-Object -Unique
+    if ($wordToComplete) {{
+        $validPossible = $validPossible | Where-Object {{ $_.StartsWith($wordToComplete) }}
+    }}
+
+    $validPossible | ForEach-Object {{
+        [System.Management.Automation.CompletionResult]::new($_, $_, 'ParameterValue', $_)
+    }}
+}}
+
+try {{
+    Set-PSReadLineOption -PredictionSource HistoryAndPlugin -ErrorAction SilentlyContinue
+    Set-PSReadLineOption -PredictionViewStyle InlineView -ErrorAction SilentlyContinue
+}} catch {{}}
+
+try {{
+    Set-PSReadLineKeyHandler -Key Tab -Function MenuComplete -ErrorAction SilentlyContinue
+}} catch {{}}
+"""
+    return script.strip()
+
+
+def get_bash_zsh_script(shell: str) -> str:
+    from lean.commands.lean import lean
+    commands_list = get_all_commands(lean)
+    commands_csv = ' '.join(commands_list)
+
+    script = f"""
+# lean CLI autocomplete
+_lean_complete() {{
+    local IFS=$'\\n'
+    local LEAN_COMMANDS=({commands_csv})
+    local cur="${{COMP_WORDS[*]:1:${{#COMP_WORDS[@]}}-1}}"
+    cur="${{cur% }}"  # strip trailing space
+    local word="${{COMP_WORDS[$COMP_CWORD]}}"
+    local prefix="${{cur% $word}}"
+
+    local possible=()
+    if [ -z "$prefix" ]; then
+        for cmd in "${{LEAN_COMMANDS[@]}}"; do
+            if [[ "$cmd" != *" "* ]]; then
+                possible+=("$cmd")
+            fi
+        done
+    else
+        for cmd in "${{LEAN_COMMANDS[@]}}"; do
+            if [[ "$cmd" == "$prefix "* ]]; then
+                local suffix="${{cmd#$prefix }}"
+                local next_word="${{suffix%% *}}"
+                possible+=("$next_word")
+            fi
+        done
+    fi
+
+    local filtered=()
+    for p in "${{possible[@]}}"; do
+        if [[ "$p" == "$word"* ]]; then
+            filtered+=("$p")
+        fi
+    done
+
+    COMPREPLY=("${{filtered[@]}}")
+}}
+complete -F _lean_complete lean
+"""
+    return script.strip()
+
+
+def get_fish_script() -> str:
+    from lean.commands.lean import lean
+    commands_list = get_all_commands(lean)
+    lines = []
+    for cmd in commands_list:
+        parts = cmd.split(' ')
+        if len(parts) == 1:
+            lines.append(f"complete -c lean -f -n '__fish_use_subcommand' -a '{cmd}'")
+        elif len(parts) == 2:
+            lines.append(f"complete -c lean -f -n '__fish_seen_subcommand_from {parts[0]}' -a '{parts[1]}'")
+    return '\n'.join(lines)
+
+
+def get_script_for_shell(shell: str) -> str:
+    if shell == 'powershell':
+        return get_powershell_script()
+    elif shell == 'fish':
+        return get_fish_script()
+    else:
+        return get_bash_zsh_script(shell)
+
+
+def get_profile_path(shell: str) -> Path:
+    if shell == 'powershell':
+        try:
+            path = subprocess.check_output(
+                ['powershell', '-NoProfile', '-Command', 'Write-Host $PROFILE'],
+                stderr=subprocess.DEVNULL
+            ).decode('utf-8').strip()
+            return Path(path)
+        except Exception:
+            return Path(os.path.expanduser(r'~\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1'))
+    elif shell == 'zsh':
+        return Path(os.path.expanduser('~/.zshrc'))
+    elif shell == 'fish':
+        return Path(os.path.expanduser('~/.config/fish/completions/lean.fish'))
+    else:
+        return Path(os.path.expanduser('~/.bashrc'))
+
+
+def manage_profile(shell: str, action: str):
+    marker_start = "# >>> lean autocomplete >>>\n"
+    marker_end = "# <<< lean autocomplete <<<\n"
+
+    profile_path = get_profile_path(shell)
+    script_content = get_script_for_shell(shell) + "\n"
+
+    content = ""
+    if profile_path.exists():
+        content = profile_path.read_text(encoding='utf-8')
+
+    if action == "install":
+        if marker_start in content:
+            echo(f"Autocomplete is already installed in {profile_path}.")
+            return
+
+        profile_path.parent.mkdir(parents=True, exist_ok=True)
+        block = f"\n{marker_start}{script_content}{marker_end}"
+        with profile_path.open('a', encoding='utf-8') as f:
+            f.write(block)
+        echo(f"✓ Installed autocomplete to {profile_path}")
+        echo("  Restart your terminal (or open a new window) for changes to take effect.")
+
+    elif action == "uninstall":
+        if marker_start not in content:
+            echo(f"Autocomplete is not installed in {profile_path}.")
+            return
+
+        start_idx = content.find(marker_start)
+        end_idx = content.find(marker_end) + len(marker_end)
+        new_content = content[:start_idx].rstrip('\n') + "\n" + content[end_idx:].lstrip('\n')
+
+        profile_path.write_text(new_content, encoding='utf-8')
+        echo(f"✓ Uninstalled autocomplete from {profile_path}")
+
+
+@group(name="autocomplete", cls=AliasedCommandGroup)
+def autocomplete() -> None:
+    """Manage shell autocomplete for Lean CLI.
+
+    Auto-detects your shell. Supports: powershell, bash, zsh, fish.
+
+    \b
+    Enable autocomplete (auto-detects shell):
+        lean enable-autocomplete
+
+    \b
+    Enable for a specific shell:
+        lean enable-autocomplete --shell bash
+
+    \b
+    Disable autocomplete:
+        lean disable-autocomplete
+    """
+    pass
+
+
+SHELL_OPTION = option(
+    '--shell', '-s',
+    type=Choice(['powershell', 'bash', 'zsh', 'fish'], case_sensitive=False),
+    default=None,
+    help='Target shell. Auto-detected if not specified.'
+)
+
+
+@autocomplete.command(name="show", help="Print the autocomplete script for your shell")
+@SHELL_OPTION
+def show(shell: str) -> None:
+    shell = shell or detect_shell()
+    echo(get_script_for_shell(shell))
+
+
+@command(name="enable-autocomplete", help="Install autocomplete into your shell profile")
+@SHELL_OPTION
+def enable_autocomplete(shell: str) -> None:
+    shell = shell or detect_shell()
+    echo(f"Detected shell: {shell}")
+    manage_profile(shell, "install")
+
+
+@command(name="disable-autocomplete", help="Remove autocomplete from your shell profile")
+@SHELL_OPTION
+def disable_autocomplete(shell: str) -> None:
+    shell = shell or detect_shell()
+    echo(f"Detected shell: {shell}")
+    manage_profile(shell, "uninstall")

lean/commands/cloud/__init__.py

@@ -12,6 +12,7 @@
 # limitations under the License.
 
 from click import group
+from lean.components.util.click_aliased_command_group import AliasedCommandGroup
 
 from lean.commands.cloud.backtest import backtest
 from lean.commands.cloud.live.live import live
@@ -21,7 +22,7 @@
 from lean.commands.cloud.status import status
 from lean.commands.cloud.object_store import object_store
 
-@group()
+@group(cls=AliasedCommandGroup)
 def cloud() -> None:
     """Interact with the QuantConnect cloud."""
     # This method is intentionally empty

lean/commands/config/__init__.py

@@ -12,14 +12,15 @@
 # limitations under the License.
 
 from click import group
+from lean.components.util.click_aliased_command_group import AliasedCommandGroup
 
 from lean.commands.config.get import get
 from lean.commands.config.list import list
 from lean.commands.config.set import set
 from lean.commands.config.unset import unset
 
 
-@group()
+@group(cls=AliasedCommandGroup)
 def config() -> None:
     """Configure Lean CLI options."""
     # This method is intentionally empty

lean/commands/data/__init__.py

@@ -12,12 +12,13 @@
 # limitations under the License.
 
 from click import group
+from lean.components.util.click_aliased_command_group import AliasedCommandGroup
 
 from lean.commands.data.download import download
 from lean.commands.data.generate import generate
 
 
-@group()
+@group(cls=AliasedCommandGroup)
 def data() -> None:
     """Download or generate data for local use."""
     # This method is intentionally empty

lean/commands/library/__init__.py

@@ -12,12 +12,13 @@
 # limitations under the License.
 
 from click import group
+from lean.components.util.click_aliased_command_group import AliasedCommandGroup
 
 from lean.commands.library.add import add
 from lean.commands.library.remove import remove
 
 
-@group()
+@group(cls=AliasedCommandGroup)
 def library() -> None:
     """Manage custom libraries in a project."""
     # This method is intentionally empty

lean/commands/private_cloud/__init__.py

@@ -12,13 +12,14 @@
 # limitations under the License.
 
 from click import group
+from lean.components.util.click_aliased_command_group import AliasedCommandGroup
 
 from lean.commands.private_cloud.start import start
 from lean.commands.private_cloud.stop import stop
 from lean.commands.private_cloud.add_compute import add_compute
 
 
-@group()
+@group(cls=AliasedCommandGroup)
 def private_cloud() -> None:
     """Interact with a QuantConnect private cloud."""
     # This method is intentionally empty

lean/components/util/click_aliased_command_group.py

@@ -15,7 +15,21 @@
 
 
 class AliasedCommandGroup(Group):
-    """A click.Group wrapper that implements command aliasing."""
+    """A click.Group wrapper that implements command aliasing and auto-completion/prefix matching."""
+
+    def get_command(self, ctx, cmd_name):
+        rv = super().get_command(ctx, cmd_name)
+        if rv is not None:
+            return rv
+
+        matches = [x for x in self.list_commands(ctx) if x.startswith(cmd_name)]
+
+        if not matches:
+            return None
+        elif len(matches) == 1:
+            return super().get_command(ctx, matches[0])
+
+        ctx.fail(f"Too many matches: {', '.join(sorted(matches))}")
 
     def command(self, *args, **kwargs):
         aliases = kwargs.pop('aliases', [])