check: existence of mentioned files

first check also sets up checks infrastructure

Makefile

@@ -1,11 +1,12 @@
 MY_INTERNALS = $(HOME)/Library/Mobile\ Documents/com~apple~TextEdit/Documents/Apple\ Internals.rtf
 DB := $(if $(DB),$(DB:.lz=),internals-$(shell sw_vers -productVersion).db)
 DB_TARGETS = db_files
+CHECK_TARGETS = check_files
 
-.PHONY: all $(DB_TARGETS)
+.PHONY: all check $(DB_TARGETS) $(CHECK_TARGETS)
 .INTERMEDIATE: $(DB)
 
-all: internals.txt $(DB).lz
+all: $(DB).lz check
 
 ifneq ($(wildcard $(MY_INTERNALS)),)
 internals.txt: $(MY_INTERNALS)
@@ -24,6 +25,10 @@ $(DB).lz: $(DB)
 	tmutil addexclusion $@
 endif
 
+check: internals.txt
+	@LANG=en sort --ignore-case $< | diff -uw $< -
+	@$(MAKE) --silent --jobs=1 $(CHECK_TARGETS)
+
 
 # MARK: - data extraction helpers
 
@@ -63,3 +68,12 @@ db_files::
 
 $(DB_TARGETS)::
 	echo 'COMMIT TRANSACTION;'
+
+
+# MARK: - check targets for internals.txt
+
+check_files: internals.txt $(DB)
+	printf '\033[1mchecking files...\033[m\n' >&2
+	grep -ow '~\?/[^,;]*' $< | sed -E 's/ \(.*\)$$//;s/^\/(etc|var)\//\/private&/' | \
+		sed "s/'/''/g;s|.*|SELECT count(*), '&' FROM files WHERE path GLOB '&';|" | \
+		sqlite3 $(DB) | sed -n "/^0|/{s/^0|//;p;}"