Fetch only necessary commits of bundled gems

Author: nobu

defs/gmake.mk

@@ -365,7 +365,7 @@ $(srcdir)/.bundle/.timestamp:
 define build-gem
 $(srcdir)/gems/src/$(1)/.git: | $(srcdir)/gems/src
 	$(ECHO) Cloning $(4)
-	$(Q) $(GIT) clone $(4) $$(@D)
+	$(Q) $(GIT) clone --depth=1 --no-tags $(4) $$(@D)
 
 $(bundled-gem-revision): \
 	$(if $(if $(wildcard $$(@)),$(filter $(3),$(shell cat $$(@)))),,PHONY) \

tool/fetch-bundled_gems.rb

@@ -35,9 +35,14 @@
 if r
   puts "fetching #{color.notice(r)} ..."
   system("git", "fetch", "origin", r, chdir: n) or abort
+  c = r
+else
+  c = ["v#{v}", v].find do |c|
+    puts "fetching #{color.notice(c)} ..."
+    system("git", "fetch", "origin", "refs/tags/#{c}:refs/tags/#{c}", chdir: n)
+  end or abort
 end
 
-c = r || "v#{v}"
 checkout = %w"git -c advice.detachedHead=false checkout"
 print %[checking out #{color.notice(c)} (v=#{color.info(v)}]
 print %[, r=#{color.info(r)}] if r