makefiles/app_dirs: find application folders recursively

Co-authored-by: Martine Lenders <martine.lenders@tu-dresden.de>

makefiles/app_dirs.blacklist

@@ -0,0 +1,21 @@
+examples/advanced_examples/bindist/
+examples/advanced_examples/pio_blink/
+examples/essentials/subfolders/
+examples/language_bindings/community_supported/wasm/
+tests/build_system/blob/
+tests/build_system/cpp_exclude/external_modules/
+tests/build_system/cpp_ext/external_modules/
+tests/build_system/external_board_dirs/esp-ci-boards/
+tests/build_system/external_board_dirs/netdev-ci-boards/
+tests/build_system/external_board_native/external_boards/
+tests/build_system/external_module_dirs/external_modules/
+tests/build_system/external_pkg_dirs/external_pkgs/
+tests/build_system/kconfig/external_modules/
+tests/build_system/kconfig/external_pkgs/
+tests/periph/qdec/boards_modded/
+tests/pkg/openwsn_sock_udp/external_modules/
+tests/pkg/tflite-micro/external_modules/
+tests/pkg/utensor/external_modules/
+tests/pkg/wolfcrypt-ed25519-verify/
+tests/sys/suit_manifest/native_flashpage/
+tests/unittests/

makefiles/app_dirs.inc.mk

@@ -3,32 +3,18 @@
 # fallback so empty RIOTBASE won't lead to "/examples/"
 RIOTBASE ?= .
 
-# 1. use wildcard to find Makefiles
-# 2. use patsubst to drop trailing "/"
-# 3. use patsubst to drop possible leading "./"
-# 4. sort
+APPS_BASE_DIRS = bootloaders examples fuzzing tests
 
-# Prepare the list of application directories
-APPLICATION_DIRS :=                   \
-    fuzzing                           \
-    bootloaders                       \
-    examples                          \
-    tests                             \
-    tests/bench                       \
-    tests/build_system                \
-    tests/core                        \
-    tests/cpu                         \
-    tests/drivers                     \
-    tests/net                         \
-    tests/periph                      \
-    tests/pkg                         \
-    tests/sys                         \
-    #
-
-APPLICATION_DIRS := $(addprefix $(RIOTBASE)/,$(APPLICATION_DIRS))
-APPLICATION_DIRS_RELATIVE := $(dir $(wildcard $(addsuffix /*/Makefile,$(APPLICATION_DIRS))))
-APPLICATION_DIRS_ABSOLUTE := $(abspath $(APPLICATION_DIRS_RELATIVE))
-APPLICATION_DIRS := $(sort $(patsubst ./%,%,$(patsubst %/,%,$(APPLICATION_DIRS_RELATIVE))))
+# 1. recursively find Makefiles
+# 2. take parent folders
+# 3. exclude build artifacts (below bin/)
+# 4. exclude false positives from app_dirs.blacklist
+# 5. sort
+APPLICATION_DIRS := $(shell find $(APPS_BASE_DIRS) -name Makefile -type f | \
+    xargs dirname | \
+    grep -vF "/bin/" | \
+    grep -vFf $(RIOTBASE)/makefiles/app_dirs.blacklist | \
+    sort | uniq)
 
 info-applications:
 	@for dir in $(APPLICATION_DIRS); do echo $$dir; done