CLI: Targetting the same file multiple times seems to duplicate the results

[nicojs]

Describe the bug

In order to save time, I'm trying to use cucumber-js to target individual features and examples (a lot of them). I'm using these arguments:

$ npx cucumber-js "features/foo.feature:33" "features/foo.feature:34"

(to target 2 examples)

However, instead of saving time, it just takes more time. It seems that both examples are now executed twice.

To Reproduce

1. Follow the nodejs example: https://github.com/cucumber/cucumber-js/blob/main/docs/nodejs_example.md
2. Execute npx cucumber-js features/simple_math.feature:19, see:

   ...
   
   1 scenario (1 passed)
   3 steps (3 passed)
   

3. Same for line 20, npx cucumber-js features/simple_math.feature:20, see:

   ...
   
   1 scenario (1 passed)
   3 steps (3 passed)
   

4. Now, execute npx cucumber-js features/simple_math.feature:19 features/simple_math.feature:20, see:

   ............
   
   4 scenarios (4 passed)
   12 steps (12 passed)
   

Expected behavior

...
2 scenario (2 passed)
6 steps (6 passed)

Desktop (please complete the following information):

• OS: Windows
• cucumberjs v7.3.0
• npm 6.14.11, node v12.21.0

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

[davidjgoss]

Thanks for the report @nicojs.

Just to clarify, it seems like you're running into this when using a Scenario Outline with an Examples table. I assume it doesn't occur with regular Scenarios?

[nicojs]

It also occurs with regular scenarios.

I've dug a little deeper and found out the issue:

cucumber-js/src/cli/configuration_builder.ts

Lines 144 to 147 in ea4d860

	async expandFeaturePaths(featurePaths: string[]): Promise<string[]> {
	featurePaths = featurePaths.map((p) => p.replace(/(:\d+)*$/g, '')) // Strip line numbers
	return this.expandPaths(featurePaths, '.feature')
	}

Feature files are expanded but not deduplicated. This fixes it:

 async expandFeaturePaths(featurePaths: string[]): Promise<string[]> { 
   featurePaths = featurePaths.map((p) => p.replace(/(:\d+)*$/g, '')) // Strip line numbers 
+  featurePaths = [...new Set(featurePaths)]; // Deduplicate the feature files
   return this.expandPaths(featurePaths, '.feature') 
 } 

You want me to create a PR? Does this warrant a feature file? Or unit testing?

[nicojs]

The fix seems straight forward enough to not deem itself worthy for a feature file IMHO 🤷‍♂️ See PR #1708

[davidjgoss]

Ah thanks, good find.

FWIW we do have a notation that supports targeting multiple lines in the same file, check out this scenario https://github.com/cucumber/cucumber-js/blob/main/features/target_specific_scenarios_by_line.feature#L40.

If you're willing to do a PR to add the deduplication though that would be great. I think another scenario in the aforementioned file (as I think that's the most likely circumstance to hit this) plus relevant unit testing would be right in terms of coverage.

[nicojs]

Ah cool! I was looking for exactly that 😆I will use that then

If you're willing to do a PR to add the deduplication though that would be great. I think another scenario in the aforementioned file (as I think that's the most likely circumstance to hit this) plus relevant unit testing would be right in terms of coverage.

PR is ready. I will add the scenario too, no problem.

[nicojs]

Ok, added it. I've transformed the scenario to a scenario outline with 2 examples. I've also manually "mutation tested" it.