Fix #1590: id metatag: "id:A..B,C..D,E"

Support searches like the following:

* score:<0,>100 (equivalent to `score:<0 or score:>100`)
* score:5,10..15,>20 (equivalent to `score:5 or score:10..15 or score:>20`)
* id:5,10..15,20..25,30 (equivalent to `id:5 or id:10..15 or id:20..25 or id:30`)

This also works inside the `search[id]` URL parameter, and inside other numeric
URL search parameters.

app/logical/concerns/searchable.rb

@@ -201,8 +201,16 @@ module Searchable
   end
 
   def attribute_matches(value, field, type = :integer)
-    operator, *args = RangeParser.parse(value, type)
+    operator, arg = RangeParser.parse(value, type)
-    relation = where_operator(field, operator, *args)
+
+    if operator == :union
+      # operator = :union, arg = [[:eq, 5], [:gt, 7], [:lt, 3]]
+      relation = arg.map do |sub_operator, sub_value|
+        where_operator(field, sub_operator, sub_value)
+      end.reduce(:or)
+    else
+      relation = where_operator(field, operator, arg)
+    end
 
     # XXX Hack to make negating the equality operator work correctly on nullable columns.
     #
@@ -210,7 +218,7 @@ module Searchable
     # This way if the relation is negated with `Post.attribute_matches(1, :approver_id).negate_relation`, it will
     # produce `WHERE approver_id != 1 OR approver_id IS NULL`. This is so the search includes NULL values; if it
     # was just `approver_id != 1`, then it would not include when approver_id is NULL.
-    if (operator in :eq | :not_eq) && args[0] != nil && has_attribute?(field) && column_for_attribute(field).null
+    if (operator in :eq | :not_eq) && arg != nil && has_attribute?(field) && column_for_attribute(field).null
       relation = relation.where.not(field => nil)
     end
 

app/logical/range_parser.rb

@@ -15,6 +15,7 @@
 #   RangeParser.parse("5..10")  => [:between, (5..10)]
 #   RangeParser.parse("5...10") => [:between, (5...10)]
 #   RangeParser.parse("5,6,7")  => [:in, [5, 6, 7]]
+#   RangeParser.parse("5,7..9") => [:union, [[:eq, 5], [:between, (7..9)]]]
 #   RangeParser.parse("any")    => [:not_eq, nil]
 #   RangeParser.parse("none")   => [:eq, nil]
 #
@@ -40,6 +41,10 @@ class RangeParser
     range = case string
     in _ if type == :enum
       [:in, string.split(/[, ]+/).map { |x| parse_value(x) }]
+    in /[, ]/ if string.match?(/<|>|\.\./) # >A,<B,C..D
+      [:union, string.split(/[, ]+/).map { |x| RangeParser.parse(x, type) }]
+    in /[, ]/ # A,B,C
+      [:in, string.split(/[, ]+/).map { |x| parse_value(x) }]
     in /\A(.+?)\.\.\.(.+)/ # A...B
       lo, hi = [parse_value($1), parse_value($2)].sort
       [:between, (lo...hi)]
@@ -54,8 +59,6 @@ class RangeParser
       [:gteq, parse_value($1)]
     in /\A>(.+)/ # >A
       [:gt, parse_value($1)]
-    in /[, ]/ # A,B,C
-      [:in, string.split(/[, ]+/).map { |x| parse_value(x) }]
     in "any"
       [:not_eq, nil]
     in "none"

test/unit/post_query_builder_test.rb

@@ -212,6 +212,19 @@ class PostQueryBuilderTest < ActiveSupport::TestCase
       assert_tag_match([posts[1], posts[0]], "id:#{posts[1].id}..#{posts[0].id}")
       assert_tag_match([posts[1], posts[0]], "id:#{posts[0].id}...#{posts[2].id}")
 
+      assert_tag_match(posts.reverse, "id:#{posts[0].id},#{posts[1].id}..#{posts[2].id}")
+      assert_tag_match(posts.reverse, "id:#{posts[0].id}..#{posts[1].id},#{posts[2].id}")
+      assert_tag_match(posts.reverse, "id:#{posts[0].id},>=#{posts[1].id}")
+      assert_tag_match(posts.reverse, "id:<=#{posts[1].id},#{posts[2].id}")
+
+      assert_tag_match([], "id:<#{posts[0].id},>#{posts[2].id}")
+      assert_tag_match([posts[2], posts[0]], "id:<=#{posts[0].id},>=#{posts[2].id}")
+      assert_tag_match([posts[2], posts[0]], "id:..#{posts[0].id},#{posts[2].id}..")
+
+      assert_tag_match([posts[1]], "id:<#{posts[0].id},#{posts[1].id},>#{posts[2].id}")
+      assert_tag_match([posts[1]], "id:#{posts[1].id},<#{posts[0].id},>#{posts[2].id}")
+      assert_tag_match([posts[1]], "id:<#{posts[0].id},>#{posts[2].id},#{posts[1].id}")
+
       assert_tag_match([posts[1], posts[0]], "-id:>#{posts[1].id}")
       assert_tag_match([posts[2], posts[1]], "-id:<#{posts[1].id}")
       assert_tag_match([posts[0]], "-id:>=#{posts[1].id}")
@@ -219,6 +232,19 @@ class PostQueryBuilderTest < ActiveSupport::TestCase
       assert_tag_match([posts[0]], "-id:#{posts[1].id}..#{posts[2].id}")
       assert_tag_match([posts[0]], "-id:#{posts[1].id},#{posts[2].id}")
 
+      assert_tag_match([], "-id:#{posts[0].id},#{posts[1].id}..#{posts[2].id}")
+      assert_tag_match([], "-id:#{posts[0].id}..#{posts[1].id},#{posts[2].id}")
+      assert_tag_match([], "-id:#{posts[0].id},>=#{posts[1].id}")
+      assert_tag_match([], "-id:<=#{posts[1].id},#{posts[2].id}")
+
+      assert_tag_match(posts.reverse, "-id:<#{posts[0].id},>#{posts[2].id}")
+      assert_tag_match([posts[1]], "-id:<=#{posts[0].id},>=#{posts[2].id}")
+      assert_tag_match([posts[1]], "-id:..#{posts[0].id},#{posts[2].id}..")
+
+      assert_tag_match([posts[2], posts[0]], "-id:<#{posts[0].id},#{posts[1].id},>#{posts[2].id}")
+      assert_tag_match([posts[2], posts[0]], "-id:#{posts[1].id},<#{posts[0].id},>#{posts[2].id}")
+      assert_tag_match([posts[2], posts[0]], "-id:<#{posts[0].id},>#{posts[2].id},#{posts[1].id}")
+
       assert_tag_match([], "id:#{posts[0].id} id:#{posts[2].id}")
       assert_tag_match([posts[0]], "-id:#{posts[1].id} -id:#{posts[2].id}")
       assert_tag_match([posts[1]], "id:>#{posts[0].id} id:<#{posts[2].id}")
@@ -1048,6 +1074,9 @@ class PostQueryBuilderTest < ActiveSupport::TestCase
 
       assert_tag_match([post1], "pixiv:none")
       assert_tag_match([post2], "pixiv:any")
+
+      assert_tag_match([], "-pixiv_id:>40,<50")
+      assert_tag_match([post2], "-pixiv_id:<40,>50")
     end
 
     should "return posts for the search: metatag" do