Improve failure messages when not expecting a list

Author: mkllnk

lib/rspec/sql.rb

@@ -15,20 +15,21 @@ module Sql; end
     match do |block|
       @queries = scribe_queries(&block)
       @matcher = Sql::QueryMatcher.new(@queries, expected)
+      expected = matcher.expected
 
       matcher.matches?
     end
 
     failure_message do |_block|
-      if expected.is_a?(Enumerator) && expected.inspect.match?(/:times>$/)
-        expected = expected.size
+      if expected.nil?
+        return "Expected at least one database query but observed none."
       end
 
       <<~MESSAGE
         Expected database queries: #{expected}
-        Actual database queries:   #{query_names}
+        Actual database queries:   #{matcher.actual}
 
-        Diff: #{Expectations.differ.diff_as_object(query_names, expected)}
+        Diff: #{Expectations.differ.diff_as_object(matcher.actual, expected)}
 
         Full query log:
 
@@ -48,10 +49,6 @@ def supports_block_expectations?
       true
     end
 
-    def query_names
-      @queries.map { |q| q[:name] || q[:sql].split.take(2).join(" ") }
-    end
-
     def query_descriptions
       @queries.map { |q| "#{q[:name]}  #{q[:sql]}" }
     end

lib/rspec/sql/query_matcher.rb

@@ -6,6 +6,8 @@ module RSpec
   module Sql
     # Compares expectations with actual queries.
     class QueryMatcher
+      attr_reader :expected
+
       def initialize(queries, expected)
         @queries = queries
         @expected = sanitize_number(expected)
@@ -18,9 +20,11 @@ def matches?
         actual == expected
       end
 
-      private
+      def actual
+        @actual ||= actual_compared_to_expected
+      end
 
-      attr_reader :expected
+      private
 
       # Support writing: `is_expected.to query_database 5.times`
       def sanitize_number(expected)
@@ -31,10 +35,6 @@ def sanitize_number(expected)
         end
       end
 
-      def actual
-        @actual ||= actual_compared_to_expected
-      end
-
       def actual_compared_to_expected
         case expected
         when Integer

spec/lib/rspec/sql_spec.rb

@@ -67,16 +67,32 @@
     )
   end
 
+  it "prints user-friendly message expecting nothing" do
+    message = error_message { expect { User.last }.not_to query_database }
+    expect(message).to eq <<~TXT
+      Expected no database queries but observed:
+
+      User Load  SELECT "users".* FROM "users" ORDER BY "users"."id" DESC LIMIT ?
+    TXT
+  end
+
+  it "prints user-friendly message expecting something" do
+    message = error_message { expect { nil }.to query_database }
+    expect(message).to eq(
+      "Expected at least one database query but observed none."
+    )
+  end
+
   it "prints user-friendly message expecting a number" do
     message = error_message { expect { User.last }.to query_database 2 }
     expect(message).to eq <<~TXT
       Expected database queries: 2
-      Actual database queries:   ["User Load"]
+      Actual database queries:   1
 
       Diff:
       @@ -1 +1 @@
       -2
-      +["User Load"]
+      +1
 
 
       Full query log:
@@ -89,12 +105,12 @@
     message = error_message { expect { User.last }.to query_database 2.times }
     expect(message).to eq <<~TXT
       Expected database queries: 2
-      Actual database queries:   ["User Load"]
+      Actual database queries:   1
 
       Diff:
       @@ -1 +1 @@
       -2
-      +["User Load"]
+      +1
 
 
       Full query log:
@@ -134,12 +150,12 @@
     # This message could be better but nobody has asked for it yet.
     expect(message).to eq <<~TXT
       Expected database queries: {:update=>{:user=>1}}
-      Actual database queries:   ["User Load"]
+      Actual database queries:   {:select=>{:users=>1}}
 
       Diff:
       @@ -1 +1 @@
       -:update => {:user=>1},
-      +["User Load"]
+      +:select => {:users=>1},
 
 
       Full query log: