Add query summary matching

This has been copied from the openfoodnetwork repository and adapted
slightly. It also needed one little fix.

This approach is quite different to our previous one and I'm wondering
if we use `User` and `Create` instead of `users` and `insert` to stay on
the higher level of Active Record. But for now this is can be a simple
replacement for the openfoodnetwork spec helper and we can evolve it
from there.

README.md

@@ -22,7 +22,7 @@ expect { nil }.to_not query_database
 expect { User.last }.to query_database 1
 expect { User.create }.to query_database 3.times
 
-# Assert specific queries:
+# Assert a specific query list:
 expect { User.last }.to query_database ["User Load"]
 
 expect { User.create!.update(name: "Jane") }.to query_database [
@@ -33,6 +33,14 @@ expect { User.create!.update(name: "Jane") }.to query_database [
   "User Update",
   "TRANSACTION",
 ]
+
+# Assert a specific query summary:
+expect { User.create!.update(name: "Jane") }.to query_database(
+  {
+    insert: { users: 1 },
+    update: { users: 1 },
+  }
+)
 ```
 
 ## Alternatives

lib/rspec/sql.rb

@@ -3,6 +3,8 @@
 require "active_support"
 require "rspec"
 
+require_relative "sql/query_summary"
+
 module RSpec
   module Sql; end
 
@@ -18,6 +20,8 @@ module Sql; end
         @queries.size == expected.size
       elsif expected.is_a?(Array)
         query_names == expected
+      elsif expected.is_a?(Hash)
+        query_summary == expected
       else
         raise "What are you expecting?"
       end
@@ -52,6 +56,10 @@ def query_descriptions
       @queries.map { |q| "#{q[:name]}  #{q[:sql]}" }
     end
 
+    def query_summary
+      Sql::QuerySummary.new(@queries).summary
+    end
+
     def scribe_queries(&)
       queries = []
 

lib/rspec/sql/query_summary.rb

@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+module RSpec
+  module Sql
+    class QuerySummary
+      QUERY_TYPES = [:delete, :insert, :select, :update].freeze
+
+      attr_reader :summary
+
+      def initialize(queries)
+        @summary = {}
+        queries.each do |payload|
+          type = get_type(payload[:sql])
+          next if QUERY_TYPES.exclude?(type) || pg_query?(payload[:sql])
+
+          table = get_table(payload[:sql])
+          @summary[type] ||= {}
+          @summary[type][table] ||= 0
+          @summary[type][table] += 1
+        end
+      end
+
+      private
+
+      def get_table(sql)
+        sql_parts = sql.split
+        case get_type(sql)
+        when :insert
+          sql_parts[2]
+        when :update
+          sql_parts[1]
+        else
+          table_index = sql_parts.index("FROM")
+          sql_parts[table_index + 1]
+        end.gsub(/(\\|")/, "").to_sym
+      end
+
+      def get_type(sql)
+        sql.split[0].downcase.to_sym
+      end
+
+      def pg_query?(sql)
+        sql.include?("SELECT a.attname") || sql.include?("pg_attribute")
+      end
+    end
+  end
+end

rspec-sql.gemspec

@@ -3,7 +3,7 @@ Gem::Specification.new do |s|
   s.version     = "0.0.0"
   s.summary     = "RSpec::Sql matcher"
   s.description = "RSpec matcher for database queries."
-  s.authors     = ["Maikel Linke"]
+  s.authors     = ["Maikel Linke", "Open Food Network contributors"]
   s.email       = "maikel@openfoodnetwork.org.au"
   s.files       = Dir["lib/**/*.rb"]
   s.homepage    = "https://github.com/openfoodfoundation/rspec-sql"

spec/lib/rspec/sql_spec.rb

@@ -57,4 +57,13 @@
       "TRANSACTION",
     ]
   end
+
+  it "expects a summary of queries" do
+    expect { User.create!.update(name: "Jane") }.to query_database(
+      {
+        insert: { users: 1 },
+        update: { users: 1 },
+      }
+    )
+  end
 end