Regression tests for double suspense/double resource fetch

[metatoaster]

As per advice, this has been added to the existing suspense_tests in examples, but given the complexity it's added as a new standalone module that exports the InstrumentedRoutes for inclusion in some other App. During this initial start I've noted some bugs with [aria-current] for CSR (which affects the <nav> towards the subpaths, and this is observed with the existing tests), and that the A hrefs don't seem to format properly as there seem to be subtle differences between actix and axum integration. I think the new test may benefit from gating behind feature flags to flip between them, and potentially the SsrMode as documented in a comment in the new module.

These tests target the issues originally reported in #2937, #2956 and #2961.

Tasks:

• Set up the original components with identifiers for selection and instrument critical paths with counters.
• Provide the base set of fixtures for the scenarios.
• Show that the basic scenarios work.
• Create the rest of the scenarios that previously failed.
• Verify that the scenarios that should pass now will fail against builds against older versions.

[metatoaster]

So there might still be a difference between the effects of CSR and Hydrated rendering on subsequent resource fetches, demonstrated in bb67d7e. For now I just document them as the expected features, but if this gets corrected later they will result in failing tests that need updating.

[metatoaster]

I've now verified that the current test cases will fail as expected for past commits, so I am happy for this to be reviewed and merged. That said, I think bb67d7e should be omitted from the squash, assuming if that's going to be the case (I generally try to make good commits but I can understand having tests be more concise to for brevity). Reason is that those tests might serve as a good standalone reference for the difference of the two different modes and having that as a standalone commit can help make it clear in the future in relations to decisions being made.

Moreover, if the [aria-current] fixes for the <A/> components are to be added, I am sure the testing for those can potentially fit in this instrumented example I've added (despite the fact that they are not suspense related, if you run the examples you will see that the CSR highlighting do not work, and that I used <a/> instead because they were buggy and in the way of the actual testing I wanted to do here).

For posterity, the following are the failures against specific key historic commits related to this issue from the past:

Test failures against 7831e4a (assumed to be beta4, with the original flaws in the reactive system that resulted in the duplicate excessive resource fetch; suspense tests were removed as not relevant yet)

Feature: Using instrumented counters for real
  Scenario: Emulate steps 1 to 5 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 2 |
       | inspect_item_root  | 0 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:18:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        5,
      >        2,
           ),
           (
               "inspect_item_root",
               0,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Emulate step 6 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 41#
   ✔  And I refresh the page
   ✔  When I select the following links
       | Target 4## |
       | Target 42# |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 1 |
       | inspect_item_root  | 2 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:32:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        4,
      >        1,
           ),
           (
               "inspect_item_root",
      <        6,
      >        2,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Emulate step 7 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 42#
   ✔  And I refresh the page
   ✔  When I select the following links
       | Target 4## |
       | Target 42# |
       | Target 41# |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 1 |
       | inspect_item_root  | 3 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:47:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        6,
      >        1,
           ),
           (
               "inspect_item_root",
      <        10,
      >        3,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Emulate step 8, "not trigger double fetch".
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
       | Target 41#   |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 2 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:62:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        9,
      >        2,
           ),
           (
               "inspect_item_root",
      <        2,
      >        1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Like above, for the "double fetch" which shouldn't happen
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
       | Target 41#   |
       | Target 3##   |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 3 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:78:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        13,
      >        3,
           ),
           (
               "inspect_item_root",
      <        3,
      >        1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Like above, but using 4## instead
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
       | Target 41#   |
       | Target 4##   |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 2 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:94:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        15,
      >        2,
           ),
           (
               "inspect_item_root",
      <        3,
      >        1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Emulate part of step 8 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the link Item Listing
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 1 |
       | inspect_item_root  | 0 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:117:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        3,
      >        1,
           ),
           (
               "inspect_item_root",
               0,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Emulate above, instead of refresh page, reset csr counters
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I click on Reset CSR Counters
   ✔  When I select the link Item Listing
   ✔  And I go check the Counters
   ✔  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 0 |
       | inspect_item_root  | 0 |
       | inspect_item_field | 0 |
  Scenario: Start with hydration from Target 41# and go up
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 41#
   ✔  And I refresh the page
   ✔  When I select the link Target 4##
   ✔  And I select the link Item Listing
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 1 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:147:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        5,
      >        1,
           ),
           (
               "inspect_item_root",
      <        4,
      >        1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Start with hydration from Target 41# and go up
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 41#
   ✔  And I click on Reset CSR Counters
   ✔  When I select the link Target 4##
   ✔  And I select the link Item Listing
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 0 |
       | inspect_item_root  | 0 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:160:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        2,
      >        0,
           ),
           (
               "inspect_item_root",
      <        2,
      >        0,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      

Test failures against 827cc0b (which demonstrates that the fix to the resource tracking drastically improved - these are mixed in synthetically as the Suspend test failures happen before and are included for comparison)

Feature: Using instrumented counters for real
  Scenario: Emulate steps 1 to 5 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 1 |
       | item_overview | 2 |
       | item_inspect  | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:18:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "item_listing",
               1,
           ),
           (
               "item_overview",
      <        3,
      >        2,
           ),
           (
               "item_inspect",
               0,
           ),
       ]
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 2 |
       | inspect_item_root  | 0 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:18:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        3,
      >        2,
           ),
           (
               "inspect_item_root",
               0,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
 
  Scenario: Emulate step 6 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 41#
   ✔  And I refresh the page
   ✔  When I select the following links
       | Target 4## |
       | Target 42# |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 0 |
       | item_overview | 1 |
       | item_inspect  | 2 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:37:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "item_listing",
               0,
           ),
           (
               "item_overview",
      <        2,
      >        1,
           ),
           (
               "item_inspect",
      <        3,
      >        2,
           ),
       ]
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 1 |
       | inspect_item_root  | 2 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:32:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
               1,
           ),
           (
               "inspect_item_root",
      <        3,
      >        2,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Emulate step 7 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 42#
   ✔  And I refresh the page
   ✔  When I select the following links
       | Target 4## |
       | Target 42# |
       | Target 41# |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 0 |
       | item_overview | 1 |
       | item_inspect  | 3 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:57:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "item_listing",
               0,
           ),
           (
               "item_overview",
      <        2,
      >        1,
           ),
           (
               "item_inspect",
      <        4,
      >        3,
           ),
       ]
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 1 |
       | inspect_item_root  | 3 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:47:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
               1,
           ),
           (
               "inspect_item_root",
      <        4,
      >        3,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
     Scenario: Emulate step 8, "not trigger double fetch".
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
       | Target 41#   |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 1 |
       | item_overview | 2 |
       | item_inspect  | 1 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:77:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "item_listing",
               1,
           ),
           (
               "item_overview",
      <        3,
      >        2,
           ),
           (
               "item_inspect",
      <        2,
      >        1,
           ),
       ]
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 2 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:62:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        3,
      >        2,
           ),
           (
               "inspect_item_root",
               1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
            
  Scenario: Like above, for the "double fetch" which shouldn't happen
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
       | Target 41#   |
       | Target 3##   |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 1 |
       | item_overview | 3 |
       | item_inspect  | 1 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:98:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "item_listing",
               1,
           ),
           (
               "item_overview",
      <        5,
      >        3,
           ),
           (
               "item_inspect",
      <        2,
      >        1,
           ),
       ]
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 3 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:78:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        5,
      >        3,
           ),
           (
               "inspect_item_root",
               1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Like above, but using 4## instead
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
       | Target 41#   |
       | Target 4##   |
   ✔  And I go check the Counters
   ✘  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 1 |
       | item_overview | 3 |
       | item_inspect  | 1 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:119:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "item_listing",
               1,
           ),
           (
               "item_overview",
      <        4,
      >        3,
           ),
           (
               "item_inspect",
      <        2,
      >        1,
           ),
       ]
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 2 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:94:9
      Matched: tests/fixtures/world/check_steps.rs:83:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        3,
      >        2,
           ),
           (
               "inspect_item_root",
               1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      

Test failures against 7c0889e (which fixed the double suspense, but naturally didn't include the Param related fix so Resource depending on Params remained broken)

Feature: Using instrumented counters for real
  Scenario: Emulate steps 1 to 5 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
   ✔  And I go check the Counters
   ✔  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 1 |
       | item_overview | 2 |
       | item_inspect  | 0 |
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 2 |
       | inspect_item_root  | 0 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:23:9
      Matched: tests/fixtures/world/check_steps.rs:84:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        3,
      >        2,
           ),
           (
               "inspect_item_root",
               0,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Emulate step 6 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 41#
   ✔  And I refresh the page
   ✔  When I select the following links
       | Target 4## |
       | Target 42# |
   ✔  And I go check the Counters
   ✔  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 0 |
       | item_overview | 1 |
       | item_inspect  | 2 |
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 1 |
       | inspect_item_root  | 2 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:42:9
      Matched: tests/fixtures/world/check_steps.rs:84:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
               1,
           ),
           (
               "inspect_item_root",
      <        3,
      >        2,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Emulate step 7 of issue #2961
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 42#
   ✔  And I refresh the page
   ✔  When I select the following links
       | Target 4## |
       | Target 42# |
       | Target 41# |
   ✔  And I go check the Counters
   ✔  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 0 |
       | item_overview | 1 |
       | item_inspect  | 3 |
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 1 |
       | inspect_item_root  | 3 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:62:9
      Matched: tests/fixtures/world/check_steps.rs:84:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
               1,
           ),
           (
               "inspect_item_root",
      <        4,
      >        3,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Emulate step 8, "not trigger double fetch".
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
       | Target 41#   |
   ✔  And I go check the Counters
   ✔  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 1 |
       | item_overview | 2 |
       | item_inspect  | 1 |
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 2 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:82:9
      Matched: tests/fixtures/world/check_steps.rs:84:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        3,
      >        2,
           ),
           (
               "inspect_item_root",
               1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Like above, for the "double fetch" which shouldn't happen
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
       | Target 41#   |
       | Target 3##   |
   ✔  And I go check the Counters
   ✔  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 1 |
       | item_overview | 3 |
       | item_inspect  | 1 |
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 3 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:103:9
      Matched: tests/fixtures/world/check_steps.rs:84:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        5,
      >        3,
           ),
           (
               "inspect_item_root",
               1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      
  Scenario: Like above, but using 4## instead
   ✔> Given I see the app
   ✔> And I select the mode Instrumented
   ✔  Given I select the link Target 3##
   ✔  And I refresh the page
   ✔  When I select the following links
       | Item Listing |
       | Target 4##   |
       | Target 41#   |
       | Target 4##   |
   ✔  And I go check the Counters
   ✔  Then I see the following counters under section
       | Suspend Calls |   |
       | item_listing  | 1 |
       | item_overview | 3 |
       | item_inspect  | 1 |
   ✘  And the following counters under section
       | Server Calls (CSR) |   |
       | list_items         | 0 |
       | get_item           | 2 |
       | inspect_item_root  | 1 |
       | inspect_item_field | 0 |
      Step failed:
      Defined: features/check_instrumented_suspense_resource.feature:124:9
      Matched: tests/fixtures/world/check_steps.rs:84:1
      Step panicked. Captured output: assertion failed: `(left == right)`
      
      Diff < left / right > :
       [
           (
               "list_items",
               0,
           ),
           (
               "get_item",
      <        3,
      >        2,
           ),
           (
               "inspect_item_root",
               1,
           ),
           (
               "inspect_item_field",
               0,
           ),
       ]
      

So yeah, the tests are shown to work retroactively, while also showing the desired improvements as the issues were corrected.