Cannot resolve template parameters of empty array #5065

AlexandruGG · 2021-05-25T07:06:22Z

Bug report

When using an empty array in a place with template parameters, PHPStan seems to not be able to resolve the needed types, assigning type *NEVER* to the types of keys and values.

Code snippet that reproduces the problem

https://phpstan.org/r/1f55bae3-c09d-49b0-be85-3f6a28e08dae

Expected output

I am not 100% sure if this is intended behaviour, please let me know if this is not a genuine bug. 🐛
I've included a couple "workarounds" that can be used to fix the error, but I'm not sure if they should be needed or not.

The same code in Psalm does not show an error: https://psalm.dev/r/0775d2d6b0

The text was updated successfully, but these errors were encountered:

phpstan-bot · 2021-09-17T13:00:52Z

@AlexandruGG After the latest commit in dev-master, PHPStan now reports different result with your code snippet:

@@ @@
-PHP 7.4 – 8.0 (1 error)
+PHP 7.4 – 8.0 (2 errors)
 ==========
 
+12: Property Collection::$source is never read, only written.
 30: Method Collection::empty() should return Collection<NewTKey of (int|string), NewT> but returns Collection<*NEVER*, *NEVER*>.
 
 PHP 7.1 – 7.3 (6 errors)

Full report

PHP 7.4 – 8.0 (2 errors)

Line	Error
12	`Property Collection::$source is never read, only written.`
30	`Method Collection::empty() should return Collection<NewTKey of (int

PHP 7.1 – 7.3 (6 errors)

Line	Error
30	`Syntax error, unexpected ':' on line 30`
30	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 30`
44	`Syntax error, unexpected T_DOUBLE_ARROW on line 44`
44	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 44`
56	`Syntax error, unexpected ':' on line 56`
56	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 56`

phpstan-bot · 2021-09-17T13:00:54Z

@AlexandruGG After the latest commit in dev-master, PHPStan now reports different result with your code snippet:

@@ @@
-PHP 7.4 – 8.0 (1 error)
+PHP 7.4 – 8.0 (2 errors)
 ==========
 
+12: Property Collection::$source is never read, only written.
 30: Method Collection::empty() should return Collection<NewTKey of (int|string), NewT> but returns Collection<*NEVER*, *NEVER*>.
 
 PHP 7.1 – 7.3 (6 errors)

Full report

PHP 7.4 – 8.0 (2 errors)

Line	Error
12	`Property Collection::$source is never read, only written.`
30	`Method Collection::empty() should return Collection<NewTKey of (int

PHP 7.1 – 7.3 (6 errors)

Line	Error
30	`Syntax error, unexpected ':' on line 30`
30	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 30`
44	`Syntax error, unexpected T_DOUBLE_ARROW on line 44`
44	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 44`
56	`Syntax error, unexpected ':' on line 56`
56	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 56`

phpstan-bot · 2021-09-23T07:56:15Z

@AlexandruGG After the latest commit in dev-master, PHPStan now reports different result with your code snippet:

@@ @@
-PHP 7.4 – 8.0 (1 error)
+PHP 7.4 – 8.0 (8 errors)
 ==========
 
+12: Property Collection::$source is never read, only written.
+28: Template type NewT of method Collection::empty() is not referenced in a parameter.
+28: Template type NewTKey of method Collection::empty() is not referenced in a parameter.
 30: Method Collection::empty() should return Collection<NewTKey of (int|string), NewT> but returns Collection<*NEVER*, *NEVER*>.
+39: Template type NewT of method Collection::emptyWorkaround() is not referenced in a parameter.
+39: Template type NewTKey of method Collection::emptyWorkaround() is not referenced in a parameter.
+53: Template type NewT of method Collection::emptyWorkaround2() is not referenced in a parameter.
+53: Template type NewTKey of method Collection::emptyWorkaround2() is not referenced in a parameter.
 
 PHP 7.1 – 7.3 (6 errors)
 ==========

Full report

PHP 7.4 – 8.0 (8 errors)

Line	Error
12	`Property Collection::$source is never read, only written.`
28	`Template type NewT of method Collection::empty() is not referenced in a parameter.`
28	`Template type NewTKey of method Collection::empty() is not referenced in a parameter.`
30	`Method Collection::empty() should return Collection<NewTKey of (int
39	`Template type NewT of method Collection::emptyWorkaround() is not referenced in a parameter.`
39	`Template type NewTKey of method Collection::emptyWorkaround() is not referenced in a parameter.`
53	`Template type NewT of method Collection::emptyWorkaround2() is not referenced in a parameter.`
53	`Template type NewTKey of method Collection::emptyWorkaround2() is not referenced in a parameter.`

PHP 7.1 – 7.3 (6 errors)

Line	Error
30	`Syntax error, unexpected ':' on line 30`
30	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 30`
44	`Syntax error, unexpected T_DOUBLE_ARROW on line 44`
44	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 44`
56	`Syntax error, unexpected ':' on line 56`
56	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 56`

phpstan-bot · 2021-09-23T08:38:26Z

@AlexandruGG After the latest commit in dev-master, PHPStan now reports different result with your code snippet:

@@ @@
 PHP 7.4 – 8.0 (1 error)
 ==========
 
-30: Method Collection::empty() should return Collection<NewTKey of (int|string), NewT> but returns Collection<*NEVER*, *NEVER*>.
+-1: Internal error: PHPStan\Rules\Methods\WrongCaseOfInheritedMethodRule::findMethod(): Argument #2 ($classReflection) must be of type PHPStan\Reflection\ClassReflection, null given, called in /var/task/vendor/phpstan/phpstan-strict-rules/src/Rules/Methods/WrongCaseOfInheritedMethodRule.php on line 40
+Run PHPStan with --debug option and post the stack trace to:
+https://github.com/phpstan/phpstan/issues/new?template=Bug_report.md
 
 PHP 7.1 – 7.3 (6 errors)
 ==========

Full report

PHP 7.4 – 8.0 (1 error)

Line	Error
-1	`Internal error: PHPStan\Rules\Methods\WrongCaseOfInheritedMethodRule::findMethod(): Argument #2 ($classReflection) must be of type PHPStan\Reflection\ClassReflection, null given, called in /var/task/vendor/phpstan/phpstan-strict-rules/src/Rules/Methods/WrongCaseOfInheritedMethodRule.php on line 40Run PHPStan with --debug option and post the stack trace to:https://github.com/phpstan/phpstan/issues/new?template=Bug_report.md`

PHP 7.1 – 7.3 (6 errors)

Line	Error
30	`Syntax error, unexpected ':' on line 30`
30	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 30`
44	`Syntax error, unexpected T_DOUBLE_ARROW on line 44`
44	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 44`
56	`Syntax error, unexpected ':' on line 56`
56	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 56`

phpstan-bot · 2022-01-06T21:18:37Z

@AlexandruGG After the latest commit in dev-master, PHPStan now reports different result with your code snippet:

@@ @@
-PHP 7.4 – 8.0 (1 error)
+PHP 7.4 – 8.0 (8 errors)
 ==========
 
+28: Template type NewTKey of method Collection::empty() is not referenced in a parameter.
+28: Template type NewT of method Collection::empty() is not referenced in a parameter.
 30: Method Collection::empty() should return Collection<NewTKey of (int|string), NewT> but returns Collection<*NEVER*, *NEVER*>.
+39: Template type NewTKey of method Collection::emptyWorkaround() is not referenced in a parameter.
+39: Template type NewT of method Collection::emptyWorkaround() is not referenced in a parameter.
+53: Template type NewTKey of method Collection::emptyWorkaround2() is not referenced in a parameter.
+53: Template type NewT of method Collection::emptyWorkaround2() is not referenced in a parameter.
+12: Property Collection::$source is never read, only written.
 
 PHP 7.1 – 7.3 (6 errors)
 ==========
 
+30: Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 30
 30: Syntax error, unexpected ':' on line 30
-30: Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 30
+44: Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 44
 44: Syntax error, unexpected T_DOUBLE_ARROW on line 44
-44: Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 44
-56: Syntax error, unexpected ':' on line 56
-56: Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 56
+56: Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 56
+56: Syntax error, unexpected ':' on line 56

Full report

PHP 7.4 – 8.0 (8 errors)

Line	Error
28	`Template type NewTKey of method Collection::empty() is not referenced in a parameter.`
28	`Template type NewT of method Collection::empty() is not referenced in a parameter.`
30	`Method Collection::empty() should return Collection<NewTKey of (int
39	`Template type NewTKey of method Collection::emptyWorkaround() is not referenced in a parameter.`
39	`Template type NewT of method Collection::emptyWorkaround() is not referenced in a parameter.`
53	`Template type NewTKey of method Collection::emptyWorkaround2() is not referenced in a parameter.`
53	`Template type NewT of method Collection::emptyWorkaround2() is not referenced in a parameter.`
12	`Property Collection::$source is never read, only written.`

PHP 7.1 – 7.3 (6 errors)

Line	Error
30	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 30`
30	`Syntax error, unexpected ':' on line 30`
44	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 44`
44	`Syntax error, unexpected T_DOUBLE_ARROW on line 44`
56	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 56`
56	`Syntax error, unexpected ':' on line 56`

drupol · 2022-01-06T21:21:29Z

I have to admit that revisiting the code-snippets after each PHPStan new commit, and displaying a comment when the result is different from previous one is a genius idea ! Congrats for this feature !!!

phpstan-bot · 2022-03-03T22:33:45Z

@AlexandruGG After the latest commit in dev-master, PHPStan now reports different result with your code snippet:

@@ @@
-PHP 7.4 – 8.0 (1 error)
+PHP 7.4 – 8.0 (7 errors)
 ==========
 
-30: Method Collection::empty() should return Collection<NewTKey of (int|string), NewT> but returns Collection<*NEVER*, *NEVER*>.
+12: Property Collection::$source is never read, only written.
+28: Template type NewT of method Collection::empty() is not referenced in a parameter.
+28: Template type NewTKey of method Collection::empty() is not referenced in a parameter.
+39: Template type NewT of method Collection::emptyWorkaround() is not referenced in a parameter.
+39: Template type NewTKey of method Collection::emptyWorkaround() is not referenced in a parameter.
+53: Template type NewT of method Collection::emptyWorkaround2() is not referenced in a parameter.
+53: Template type NewTKey of method Collection::emptyWorkaround2() is not referenced in a parameter.
 
 PHP 7.1 – 7.3 (6 errors)
 ==========

Full report

PHP 7.4 – 8.0 (7 errors)

Line	Error
12	`Property Collection::$source is never read, only written.`
28	`Template type NewT of method Collection::empty() is not referenced in a parameter.`
28	`Template type NewTKey of method Collection::empty() is not referenced in a parameter.`
39	`Template type NewT of method Collection::emptyWorkaround() is not referenced in a parameter.`
39	`Template type NewTKey of method Collection::emptyWorkaround() is not referenced in a parameter.`
53	`Template type NewT of method Collection::emptyWorkaround2() is not referenced in a parameter.`
53	`Template type NewTKey of method Collection::emptyWorkaround2() is not referenced in a parameter.`

PHP 7.1 – 7.3 (6 errors)

Line	Error
30	`Syntax error, unexpected ':' on line 30`
30	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 30`
44	`Syntax error, unexpected T_DOUBLE_ARROW on line 44`
44	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 44`
56	`Syntax error, unexpected ':' on line 56`
56	`Syntax error, unexpected T_STRING, expecting T_PAAMAYIM_NEKUDOTAYIM on line 56`

ondrejmirtes · 2022-03-04T09:25:06Z

Fixed: phpstan/phpstan-src@c2b9e71

drupol · 2022-03-04T09:32:31Z

Cool ! Thanks @ondrejmirtes ! Looking forward to test this in the next release.

Closes phpstan/phpstan#5757 Closes phpstan/phpstan#5065 Closes phpstan/phpstan#3400 Closes phpstan/phpstan#6353

AlexandruGG · 2022-03-04T16:24:12Z

Nice one, thank you very much 🚀

github-actions · 2022-04-05T00:00:22Z

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.

AlexandruGG mentioned this issue May 25, 2021

SA Checks: fromIterable, empty loophp/collection#96

Merged

5 tasks

ondrejmirtes added the bug label May 25, 2021

ondrejmirtes added this to the Generics milestone May 25, 2021

ondrejmirtes closed this as completed Mar 4, 2022

ondrejmirtes added a commit to phpstan/phpstan-src that referenced this issue Mar 4, 2022

Regression tests

6212d8c

Closes phpstan/phpstan#5757 Closes phpstan/phpstan#5065 Closes phpstan/phpstan#3400 Closes phpstan/phpstan#6353

spackmat mentioned this issue Mar 9, 2022

Introduced in 1.4.8: ArrayCollection->get() treated as always null in foreach loop #6774

Closed

github-actions bot locked as resolved and limited conversation to collaborators Apr 5, 2022

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Cannot resolve template parameters of empty array #5065

Cannot resolve template parameters of empty array #5065

AlexandruGG commented May 25, 2021

phpstan-bot commented Sep 17, 2021

PHP 7.4 – 8.0 (2 errors)

PHP 7.1 – 7.3 (6 errors)

phpstan-bot commented Sep 17, 2021

PHP 7.4 – 8.0 (2 errors)

PHP 7.1 – 7.3 (6 errors)

phpstan-bot commented Sep 23, 2021

PHP 7.4 – 8.0 (8 errors)

PHP 7.1 – 7.3 (6 errors)

phpstan-bot commented Sep 23, 2021

PHP 7.4 – 8.0 (1 error)

PHP 7.1 – 7.3 (6 errors)

phpstan-bot commented Jan 6, 2022

PHP 7.4 – 8.0 (8 errors)

PHP 7.1 – 7.3 (6 errors)

drupol commented Jan 6, 2022

phpstan-bot commented Mar 3, 2022

PHP 7.4 – 8.0 (7 errors)

PHP 7.1 – 7.3 (6 errors)

ondrejmirtes commented Mar 4, 2022

drupol commented Mar 4, 2022

AlexandruGG commented Mar 4, 2022

github-actions bot commented Apr 5, 2022

Cannot resolve template parameters of empty array #5065

Cannot resolve template parameters of empty array #5065

Comments

AlexandruGG commented May 25, 2021

Bug report

Code snippet that reproduces the problem

Expected output

phpstan-bot commented Sep 17, 2021

PHP 7.4 – 8.0 (2 errors)

PHP 7.1 – 7.3 (6 errors)

phpstan-bot commented Sep 17, 2021

PHP 7.4 – 8.0 (2 errors)

PHP 7.1 – 7.3 (6 errors)

phpstan-bot commented Sep 23, 2021

PHP 7.4 – 8.0 (8 errors)

PHP 7.1 – 7.3 (6 errors)

phpstan-bot commented Sep 23, 2021

PHP 7.4 – 8.0 (1 error)

PHP 7.1 – 7.3 (6 errors)

phpstan-bot commented Jan 6, 2022

PHP 7.4 – 8.0 (8 errors)

PHP 7.1 – 7.3 (6 errors)

drupol commented Jan 6, 2022

phpstan-bot commented Mar 3, 2022

PHP 7.4 – 8.0 (7 errors)

PHP 7.1 – 7.3 (6 errors)

ondrejmirtes commented Mar 4, 2022

drupol commented Mar 4, 2022

AlexandruGG commented Mar 4, 2022

github-actions bot commented Apr 5, 2022