keep generated documentation in a separate directory

- helps navigating the code as it highlights which files are generated
- makes it less error prone when working incrementally
  (although this should be just fixed by building out of tree)

src/nix/help-stores.md

@@ -1,46 +0,0 @@
-R"(
-
-Nix supports different types of stores. These are described below.
-
-## Store URL format
-
-Stores are specified using a URL-like syntax. For example, the command
-
-```console
-# nix path-info --store https://cache.nixos.org/ --json \
-  /nix/store/a7gvj343m05j2s32xcnwr35v31ynlypr-coreutils-9.1
-```
-
-fetches information about a store path in the HTTP binary cache
-located at https://cache.nixos.org/, which is a type of store.
-
-Store URLs can specify **store settings** using URL query strings,
-i.e. by appending `?name1=value1&name2=value2&...` to the URL. For
-instance,
-
-```
---store ssh://machine.example.org?ssh-key=/path/to/my/key
-```
-
-tells Nix to access the store on a remote machine via the SSH
-protocol, using `/path/to/my/key` as the SSH private key. The
-supported settings for each store type are documented below.
-
-The special store URL `auto` causes Nix to automatically select a
-store as follows:
-
-* Use the [local store](#local-store) `/nix/store` if `/nix/var/nix`
-  is writable by the current user.
-
-* Otherwise, if `/nix/var/nix/daemon-socket/socket` exists, [connect
-  to the Nix daemon listening on that socket](#local-daemon-store).
-
-* Otherwise, on Linux only, use the [local chroot store](#local-store)
-  `~/.local/share/nix/root`, which will be created automatically if it
-  does not exist.
-
-* Otherwise, use the [local store](#local-store) `/nix/store`.
-
-@stores@
-
-)"

src/nix/local.mk

@@ -31,10 +31,23 @@ src/nix/develop.cc: src/nix/get-env.sh.gen.hh
 
 src/nix-channel/nix-channel.cc: src/nix-channel/unpack-channel.nix.gen.hh
 
-src/nix/main.cc: doc/manual/generate-manpage.nix.gen.hh doc/manual/utils.nix.gen.hh doc/manual/generate-settings.nix.gen.hh doc/manual/generate-store-info.nix.gen.hh
+src/nix/main.cc: \
+  doc/manual/generate-manpage.nix.gen.hh \
+  doc/manual/utils.nix.gen.hh doc/manual/generate-settings.nix.gen.hh \
+  doc/manual/generate-store-info.nix.gen.hh \
+  src/nix/generated-doc/help-stores.md
 
-src/nix/doc/files/%.md: doc/manual/src/command-ref/files/%.md
+src/nix/generated-doc/files/%.md: doc/manual/src/command-ref/files/%.md
 	@mkdir -p $$(dirname $@)
 	@cp $< $@
 
-src/nix/profile.cc: src/nix/profile.md src/nix/doc/files/profiles.md.gen.hh
+src/nix/profile.cc: src/nix/profile.md src/nix/generated-doc/files/profiles.md.gen.hh
+
+src/nix/generated-doc/help-stores.md: doc/manual/src/store/types/index.md.in
+	@mkdir -p $$(dirname $@)
+	@echo 'R"(' >> $@.tmp
+	@echo >> $@.tmp
+	@cat $^ >> $@.tmp
+	@echo >> $@.tmp
+	@echo ')"' >> $@.tmp
+	@mv $@.tmp $@

src/nix/main.cc

@@ -297,7 +297,7 @@ struct CmdHelpStores : Command
     std::string doc() override
     {
         return
-          #include "help-stores.md"
+          #include "generated-doc/help-stores.md"
           ;
     }
 

src/nix/profile.md

@@ -11,7 +11,7 @@ them to be rolled back easily.
 
 )""
 
-#include "doc/files/profiles.md.gen.hh"
+#include "generated-doc/files/profiles.md.gen.hh"
 
 R""(