Rewrite require! and change depends-on!

depends-on! was changed to no longer load a specified module's
packages.el, but to preform a module-enabled assertion. It emits an
error if the linked module isn't (or specified flags aren't) enabled.

core/core-modules.el

@@ -409,22 +409,29 @@ to have them return non-nil (or exploit that to overwrite Doom's config)."
                          (substring (symbol-name when) 1)))
        ,@body)))
 
-(defmacro require! (category module &rest plist)
-  "Loads the module specified by CATEGORY (a keyword) and MODULE (a symbol)."
-  `(let ((module-path (doom-module-locate-path ,category ',module)))
+(defmacro require! (category module &rest flags)
+  "Loads the CATEGORY MODULE module with FLAGS.
+
+CATEGORY is a keyword, MODULE is a symbol and FLAGS are symbols.
+
+  (require! :lang php +lsp)
+
+This is for testing and internal use. This is not the correct way to enable a
+module."
+  `(let ((doom-modules ,doom-modules)
+         (module-path (doom-module-locate-path ,category ',module)))
      (doom-module-set
       ,category ',module
-      ,@(when plist
-          (let ((old-plist (doom-module-get category module)))
-            (unless (plist-member plist :flags)
-              (plist-put plist :flags (plist-get old-plist :flags)))
-            (unless (plist-member plist :path)
-              (plist-put plist :path (or (plist-get old-plist :path)
-                                         (doom-module-locate-path category module)))))
+      ,@(let ((plist (doom-module-get category module)))
+          (when flags
+            (plist-put plist :flags flags))
+          (unless (plist-member plist :path)
+            (plist-put plist :path (doom-module-locate-path category module)))
           plist))
      (if (directory-name-p module-path)
          (condition-case-unless-debug ex
-             (let ((doom--current-module ',(cons category module)))
+             (let ((doom--current-module ',(cons category module))
+                   (doom--current-flags ',flags))
                (load! "init" module-path :noerror)
                (let ((doom--stage 'config))
                  (load! "config" module-path :noerror)))

core/core-packages.el

@@ -215,8 +215,7 @@ elsewhere."
                (not (memq ',name doom-disabled-packages)))))))
 
 (defmacro packages! (&rest packages)
-  "A convenience macro like `package!', but allows you to declare multiple
-packages at once.
+  "A convenience macro for `package!' for declaring multiple packages at once.
 
 Only use this macro in a module's packages.el file."
   (doom--assert-stage-p 'packages #'packages!)
@@ -234,19 +233,27 @@ Only use this macro in a module's packages.el file."
    (cl-loop for pkg in packages
             collect (macroexpand `(package! ,pkg :disable t)))))
 
-(defmacro depends-on! (module submodule &optional flags)
-  "Declares that this module depends on another.
+(defmacro depends-on! (category module &rest flags)
+  "Declares that this CATEGORY depends on another.
 
-Only use this macro in a module's packages.el file.
+Emits a warning if CATEGORY MODULE isn't enabled, or is enabled without FLAGS.
 
-MODULE is a keyword, and SUBMODULE is a symbol. Under the hood, this simply
-loads MODULE SUBMODULE's packages.el file."
+Only use this macro in a CATEGORY's packages.el file."
   (doom--assert-stage-p 'packages #'depends-on!)
-  `(let ((doom-modules ,doom-modules)
-         (flags ,flags))
-     (when flags
-       (doom-module-put ,module ',submodule :flags flags))
-     (load! "packages" ,(doom-module-locate-path module submodule) t)))
+  `(let ((desired-flags ',flags))
+     (unless (doom-module-locate-path ,category ',module)
+       (error "The '%s %s' module is required, but doesn't exist"
+              ,category ',module))
+     (unless (doom-module-p ,category ',module)
+       (error "The '%s %s' module is required, but disabled"
+              ,category ',module))
+     (let ((flags (doom-module-get ,category ',module :flags)))
+       (when (and desired-flags
+                  (/= (length (cl-intersection flags desired-flags))
+                      (length desired-flags)))
+         (error "The '%s %s' module is missing the required %S flag(s)"
+                ,category ',module
+                (cl-set-difference desired-flags flags))))))
 
 (provide 'core-packages)
 ;;; core-packages.el ends here