[Refactor] `qmk find` (#21096)

2 files changed, 90 insertions, 25 deletions

diff --git a/lib/python/qmk/cli/find.py b/lib/python/qmk/cli/find.py
index 55a0530092..8f3a29c90c 100644
--- a/lib/python/qmk/cli/find.py
+++ b/lib/python/qmk/cli/find.py
@@ -1,7 +1,7 @@
 """Command to search through all keyboards and keymaps for a given search criteria.
 """
 from milc import cli
-from qmk.search import search_keymap_targets
+from qmk.search import filter_help, search_keymap_targets
 
 
 @cli.argument(
@@ -11,7 +11,7 @@ from qmk.search import search_keymap_targets
     action='append',
     default=[],
     help=  # noqa: `format-python` and `pytest` don't agree here.
-    "Filter the list of keyboards based on their info.json data. Accepts the formats key=value, function(key), or function(key,value), eg. 'features.rgblight=true'. Valid functions are 'absent', 'contains', 'exists' and 'length'. May be passed multiple times; all filters need to match. Value may include wildcards such as '*' and '?'."  # noqa: `format-python` and `pytest` don't agree here.
+    f"Filter the list of keyboards based on their info.json data. Accepts the formats key=value, function(key), or function(key,value), eg. 'features.rgblight=true'. Valid functions are {filter_help()}. May be passed multiple times; all filters need to match. Value may include wildcards such as '*' and '?'."  # noqa: `format-python` and `pytest` don't agree here.
 )
 @cli.argument('-p', '--print', arg_only=True, action='append', default=[], help="For each matched target, print the value of the supplied info.json key. May be passed multiple times.")
 @cli.argument('-km', '--keymap', type=str, default='default', help="The keymap name to build. Default is 'default'.")
diff --git a/lib/python/qmk/search.py b/lib/python/qmk/search.py
index 84cf6cbe32..33550a3db2 100644
--- a/lib/python/qmk/search.py
+++ b/lib/python/qmk/search.py
@@ -5,7 +5,7 @@ import functools
 import fnmatch
 import logging
 import re
-from typing import List, Tuple
+from typing import Callable, List, Optional, Tuple
 from dotty_dict import dotty, Dotty
 from milc import cli
 
@@ -15,6 +15,82 @@ from qmk.keyboard import list_keyboards, keyboard_folder
 from qmk.keymap import list_keymaps, locate_keymap
 from qmk.build_targets import KeyboardKeymapBuildTarget, BuildTarget
 
+TargetInfo = Tuple[str, str, dict]
+
+
+# by using a class for filters, we dont need to worry about capturing values
+# see details <https://github.com/qmk/qmk_firmware/pull/21090>
+class FilterFunction:
+    """Base class for filters.
+    It provides:
+        - __init__: capture key and value
+
+    Each subclass should provide:
+        - func_name: how it will be specified on CLI
+            >>> qmk find -f <func_name>...
+        - apply: function that actually applies the filter
+            ie: return whether the input kb/km satisfies the condition
+    """
+
+    key: str
+    value: Optional[str]
+
+    func_name: str
+    apply: Callable[[TargetInfo], bool]
+
+    def __init__(self, key, value):
+        self.key = key
+        self.value = value
+
+
+class Exists(FilterFunction):
+    func_name = "exists"
+
+    def apply(self, target_info: TargetInfo) -> bool:
+        _kb, _km, info = target_info
+        return self.key in info
+
+
+class Absent(FilterFunction):
+    func_name = "absent"
+
+    def apply(self, target_info: TargetInfo) -> bool:
+        _kb, _km, info = target_info
+        return self.key not in info
+
+
+class Length(FilterFunction):
+    func_name = "length"
+
+    def apply(self, target_info: TargetInfo) -> bool:
+        _kb, _km, info = target_info
+        return (self.key in info and len(info[self.key]) == int(self.value))
+
+
+class Contains(FilterFunction):
+    func_name = "contains"
+
+    def apply(self, target_info: TargetInfo) -> bool:
+        _kb, _km, info = target_info
+        return (self.key in info and self.value in info[self.key])
+
+
+def _get_filter_class(func_name: str, key: str, value: str) -> Optional[FilterFunction]:
+    """Initialize a filter subclass based on regex findings and return it.
+    None if no there's no filter with the name queried.
+    """
+
+    for subclass in FilterFunction.__subclasses__():
+        if func_name == subclass.func_name:
+            return subclass(key, value)
+
+    return None
+
+
+def filter_help() -> str:
+    names = [f"'{f.func_name}'" for f in FilterFunction.__subclasses__()]
+    return ", ".join(names[:-1]) + f" and {names[-1]}"
+
 
 def _set_log_level(level):
     cli.acquire_lock()
@@ -48,11 +124,12 @@ def _keymap_exists(keyboard, keymap):
         return keyboard if locate_keymap(keyboard, keymap) is not None else None
 
 
-def _load_keymap_info(kb_km):
+def _load_keymap_info(target: Tuple[str, str]) -> TargetInfo:
     """Returns a tuple of (keyboard, keymap, info.json) for the given keyboard/keymap combination.
     """
+    kb, km = target
     with ignore_logging():
-        return (kb_km[0], kb_km[1], keymap_json(kb_km[0], kb_km[1]))
+        return (kb, km, keymap_json(kb, km))
 
 
 def expand_make_targets(targets: List[str]) -> List[Tuple[str, str]]:
@@ -139,26 +216,14 @@ def _filter_keymap_targets(target_list: List[Tuple[str, str]], filters: List[str
                 key = function_match.group('key')
                 value = function_match.group('value')
 
-                if value is not None:
-                    if func_name == 'length':
-                        valid_keymaps = filter(lambda e, key=key, value=value: key in e[2] and len(e[2].get(key)) == int(value), valid_keymaps)
-                    elif func_name == 'contains':
-                        valid_keymaps = filter(lambda e, key=key, value=value: key in e[2] and value in e[2].get(key), valid_keymaps)
-                    else:
-                        cli.log.warning(f'Unrecognized filter expression: {function_match.group(0)}')
-                        continue
-
-                    cli.log.info(f'Filtering on condition: {{fg_green}}{func_name}{{fg_reset}}({{fg_cyan}}{key}{{fg_reset}}, {{fg_cyan}}{value}{{fg_reset}})...')
-                else:
-                    if func_name == 'exists':
-                        valid_keymaps = filter(lambda e, key=key: key in e[2], valid_keymaps)
-                    elif func_name == 'absent':
-                        valid_keymaps = filter(lambda e, key=key: key not in e[2], valid_keymaps)
-                    else:
-                        cli.log.warning(f'Unrecognized filter expression: {function_match.group(0)}')
-                        continue
-
-                    cli.log.info(f'Filtering on condition: {{fg_green}}{func_name}{{fg_reset}}({{fg_cyan}}{key}{{fg_reset}})...')
+                filter_class = _get_filter_class(func_name, key, value)
+                if filter_class is None:
+                    cli.log.warning(f'Unrecognized filter expression: {function_match.group(0)}')
+                    continue
+                valid_keymaps = filter(filter_class.apply, valid_keymaps)
+
+                value_str = f", {{fg_cyan}}{value}{{fg_reset}})" if value is not None else ""
+                cli.log.info(f'Filtering on condition: {{fg_green}}{func_name}{{fg_reset}}({{fg_cyan}}{key}{{fg_reset}}{value_str}...')
 
             elif equals_match is not None:
                 key = equals_match.group('key')