Fix JSON Formatter

CHANGELOG.md

@@ -18,6 +18,12 @@ Please visit [cucumber/CONTRIBUTING.md](https://github.com/cucumber/cucumber/blo
 
 - Do not serialize Messages::Hook#tag_expression if it is empty.
   ([PR#1579](https://github.com/cucumber/cucumber-ruby/pull/1579))
+
+- JSON Formatter uses "pretty" output format
+  ([PR#1580](https://github.com/cucumber/cucumber-ruby/pull/1580))
+
+- Fixed JSON Formatter "end of background" detection.
+  ([PR#1580](https://github.com/cucumber/cucumber-ruby/pull/1580))
 
 ### Changed
 

features/docs/writing_support_code/attachments.feature

@@ -51,4 +51,6 @@ Feature: Attachments
 
   Scenario: With json formatter, files can be attached given their path
     When I run `cucumber --format json features/attaching_screenshot_with_mediatype.feature`
-    Then the output should contain "embeddings\":[{\"mime_type\":\"image/png\",\"data\":\"Zm9v\"}]"
+    Then the output should contain "embeddings\":"
+    And the output should contain "\"mime_type\": \"image/png\","
+    And the output should contain "\"data\": \"Zm9v\""

lib/cucumber/formatter/json.rb

@@ -81,7 +81,7 @@ def on_test_case_finished(event)
       end
 
       def on_test_run_finished(_event)
-        @io.write(JSON.generate(@feature_hashes, pretty: true))
+        @io.write(JSON.pretty_generate(@feature_hashes))
       end
 
       def attach(src, mime_type)
@@ -105,7 +105,7 @@ def same_feature_as_previous_test_case?(test_case)
       end
 
       def first_step_after_background?(test_step)
-        @in_background && test_step.location.lines.max >= @test_case_hash[:line]
+        @in_background && test_step.location.file == @feature_hash[:uri] && test_step.location.lines.max >= @test_case_hash[:line]
       end
 
       def internal_hook?(test_step)