feat: ruby and native gems always install libxml2/libxslt headers

Also, restore VERSION_INFO["libxml"]["libxml2_path"] when using
packaged libraries, so Nokogumbo can find all the headers.

Fixes #1788

.gitignore

@@ -24,8 +24,9 @@ ext/java/Canna
 ext/java/nokogiri/**/*.class
 ext/nokogiri/*.dll
 gems
-lib/nokogiri/**/nokogiri.so
 lib/nokogiri/**/nokogiri.bundle
+lib/nokogiri/**/nokogiri.so
+lib/nokogiri/include
 lib/nokogiri/nokogiri.jar
 pkg
 ports

Rakefile

@@ -37,11 +37,13 @@ HOE = Hoe.spec "nokogiri" do |hoe|
   hoe.markdown_linkify_files = FileList["*.md"]
 
   hoe.clean_globs += [
-    "nokogiri.gemspec",
-    "lib/nokogiri/nokogiri.{bundle,jar,rb,so}",
-    "lib/nokogiri/[0-9].[0-9]",
-    "coverage",
     "concourse/images/*.generated",
+    "coverage",
+    "lib/nokogiri/[0-9].[0-9]",
+    "lib/nokogiri/include",
+    "lib/nokogiri/nokogiri.{bundle,jar,rb,so}",
+    "nokogiri.gemspec",
+    "tmp",
   ]
   hoe.clean_globs += Dir.glob("ports/*").reject { |d| d =~ %r{/archives$} }
 

ext/nokogiri/extconf.rb

@@ -445,6 +445,14 @@ def process_recipe(name, version, static_p, cross_p)
   end
 end
 
+def copy_packaged_libraries_headers(to_path:, from_recipes:)
+  FileUtils.rm_rf(to_path, secure: true)
+  FileUtils.mkdir(to_path)
+  from_recipes.each do |recipe|
+    FileUtils.cp_r(Dir[File.join(recipe.path, 'include/*')], to_path)
+  end
+end
+
 def do_help
   print NOKOGIRI_HELP_MESSAGE
   exit! 0
@@ -765,6 +773,20 @@ def configure
 # When compiling during installation, install nokogiri's header files into lib/nokogiri/include
 $INSTALLFILES << ["*.h", "$(rubylibdir)/include"]
 
+unless using_system_libraries?
+  if cross_build_p
+    # When precompiling native gems, copy packaged libraries' headers to lib/nokogiri/include to get
+    # picked up by the cross-compiling callback in the extension task at package time
+    copy_packaged_libraries_headers(to_path: File.join(PACKAGE_ROOT_DIR, "lib/nokogiri/include"),
+                                    from_recipes: [libxml2_recipe, libxslt_recipe])
+  else
+    # When compiling during installation, install packaged libraries' header files into lib/nokogiri/include
+    copy_packaged_libraries_headers(to_path: "include",
+                                    from_recipes: [libxml2_recipe, libxslt_recipe])
+    $INSTALLFILES << ["include/**/*.h", "$(rubylibdir)"]
+  end
+end
+
 create_makefile('nokogiri/nokogiri')
 
 if enable_config('clean', true)
@@ -778,5 +800,4 @@ def configure
     EOF
   end
 end
-
 # :startdoc:

lib/nokogiri/version/info.rb

@@ -90,6 +90,9 @@ def to_hash
               libxml["source"] = "packaged"
               libxml["precompiled"] = libxml2_precompiled?
               libxml["patches"] = Nokogiri::LIBXML2_PATCHES
+
+              # this is for nokogumbo and shouldn't be forever
+              libxml["libxml2_path"] = File.expand_path(File.join(File.dirname(__FILE__), "../../nokogiri"))
             else
               libxml["source"] = "system"
             end

rakelib/cross-ruby.rake

@@ -353,12 +353,20 @@ else
       spec.dependencies.reject! { |dep| dep.name=='mini_portile2' }
 
       # when pre-compiling a native gem, package all the C headers in lib/nokogiri/include:
+      # - packaged libraries' headers
       # - nokogiri's headers
       #
       # (see the $INSTALLFILES section of extconf.rb for complementary behavior)
       # (see scripts/test-gem-file-contents and scripts/test-gem-installation for tests)
       headers_dir = "lib/nokogiri/include"
 
+      ["libxml2", "libxslt"].each do |lib|
+        unless File.directory?(File.join(headers_dir, lib))
+          # these should have been copied during cross-compilation
+          raise "#{lib} headers are not present in #{headers_dir}"
+        end
+      end
+
       Dir.glob("ext/nokogiri/*.h").each do |header|
         FileUtils.cp(header, headers_dir)
       end

scripts/test-gem-file-contents

@@ -107,7 +107,7 @@ describe File.basename(gemfile) do
     end
 
     it "does not contain header files in lib/nokogiri/include" do
-      # these are copied to lib/nokogiri/include during compilation, not packaged
+      # these will be copied to lib/nokogiri/include during compilation, not packaged
       assert_empty(gemfile_contents.grep(%r{^lib/.*\.h$}))
     end
 
@@ -145,7 +145,7 @@ describe File.basename(gemfile) do
     end
 
     it "contains packaged libraries' header files in lib/nokogiri/include" do
-      skip "until we fix https://github.com/sparklemotion/nokogiri/pull/1788"
+      # https://github.com/sparklemotion/nokogiri/pull/1788
       assert_includes(gemfile_contents, "lib/nokogiri/include/libxml2/libxml/tree.h")
       assert_includes(gemfile_contents, "lib/nokogiri/include/libxslt/xslt.h")
       assert_includes(gemfile_contents, "lib/nokogiri/include/libexslt/exslt.h")

scripts/test-gem-installation

@@ -55,7 +55,7 @@ describe gemspec.full_name do
 
   describe "cruby" do
     it "installs nokogiri headers" do
-      skip "until we fix https://github.com/sparklemotion/nokogiri/pull/1788"
+      # https://github.com/sparklemotion/nokogiri/pull/1788
       assert(File.directory?(nokogiri_include_dir),
              "expected directory to exist: #{nokogiri_include_dir}")
 
@@ -80,15 +80,15 @@ describe gemspec.full_name do
     describe "library" do
       describe "packaged" do
         it "declares where headers are installed" do
-          skip "until we fix https://github.com/sparklemotion/nokogiri/pull/1788"
+          # https://github.com/sparklemotion/nokogiri/pull/1788
           # this is for nokogumbo and shouldn't be forever
           nokogiri_include_parent_dir = File.dirname(nokogiri_include_dir)
           assert_equal(nokogiri_include_parent_dir, Nokogiri::VERSION_INFO["libxml"]["libxml2_path"],
                        "expected Nokogiri::VERSION_INFO to point to #{nokogiri_include_parent_dir}")
         end
 
         it "installs packaged libraries' headers" do
-          skip "until we fix https://github.com/sparklemotion/nokogiri/pull/1788"
+          # https://github.com/sparklemotion/nokogiri/pull/1788
           packaged_library_header_files.each do |header|
             assert(File.file?(File.join(nokogiri_include_dir, header)),
                    "expected #{header} to be installed in #{nokogiri_include_dir}")