How to do simple generics

[szepeviktor]

Bug report

There is a function that receives a parameter of string|int and returns string or integer.

Code snippet that reproduces the problem

https://phpstan.org/r/984d90d3-9515-4250-8613-cfc69b719abf

Expected output

No error.

Please help me achieve this.
Thank you.

[ondrejmirtes]

This is fine, it should work.

[phpstan-bot]

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

@@ @@
 PHP 8.0 (1 error)
 ==========
 
-11: Function bar() should return T of int|string but returns T of int.
+ 8: Function bar() should return T of int|string but return statement is missing.
 
 PHP 7.1 – 7.4 (2 errors)
 ==========
 
- 8: Function bar() uses native union types but they're supported only on PHP 8.0 and later.
-11: Function bar() should return T of int|string but returns T of int.
+ 8: Function bar() should return T of int|string but return statement is missing.
+ 8: Function bar() uses native union types but they're supported only on PHP 8.0 and later.

Full report

PHP 8.0 (1 error)

Line	Error
8	`Function bar() should return T of int

PHP 7.1 – 7.4 (2 errors)

Line	Error
8	`Function bar() should return T of int
8	Function bar() uses native union types but they're supported only on PHP 8.0 and later.

[szepeviktor]

Function bar() should return T of int|string but return statement is missing.

@ondrejmirtes The last commit made PHPStan miss the return statement.

[phpstan-bot]

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

@@ @@
-PHP 8.0 (1 error)
+PHP 8.0 (3 errors)
 ==========
 
+ 8: PHPDoc tag @param for parameter $key with type T of int|string is not subtype of native type int|string.
+ 8: PHPDoc tag @return with type T of int|string is not subtype of native type int|string.
 11: Function bar() should return T of int|string but returns T of int.
 
-PHP 7.1 – 7.4 (2 errors)
+PHP 7.1 – 7.4 (4 errors)
 ==========
 
  8: Function bar() uses native union types but they're supported only on PHP 8.0 and later.
+ 8: PHPDoc tag @param for parameter $key with type T of int|string is not subtype of native type int|string.
+ 8: PHPDoc tag @return with type T of int|string is not subtype of native type int|string.
 11: Function bar() should return T of int|string but returns T of int.

Full report

PHP 8.0 (3 errors)

Line	Error
8	`PHPDoc tag @param for parameter $key with type T of int
8	`PHPDoc tag @return with type T of int
11	`Function bar() should return T of int

PHP 7.1 – 7.4 (4 errors)

Line	Error
8	Function bar() uses native union types but they're supported only on PHP 8.0 and later.
8	`PHPDoc tag @param for parameter $key with type T of int
8	`PHPDoc tag @return with type T of int
11	`Function bar() should return T of int

[ondrejmirtes]

@arnaud-lb Oops, we broke it! T of string|int SHOULD be a subtype of string|int: https://phpstan.org/r/094e0fad-e14c-4343-877d-403f5d7e89e0

[phpstan-bot]

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

@@ @@
-PHP 8.0 – 8.1 (3 errors)
+PHP 8.0 – 8.1 (1 error)
 ==========
 
- 8: PHPDoc tag @param for parameter $key with type T of int|string is not subtype of native type int|string.
- 8: PHPDoc tag @return with type T of int|string is not subtype of native type int|string.
 11: Function bar() should return T of int|string but returns T of int.
 
-PHP 7.1 – 7.4 (4 errors)
+PHP 7.1 – 7.4 (2 errors)
 ==========
 
  8: Function bar() uses native union types but they're supported only on PHP 8.0 and later.
- 8: PHPDoc tag @param for parameter $key with type T of int|string is not subtype of native type int|string.
- 8: PHPDoc tag @return with type T of int|string is not subtype of native type int|string.
 11: Function bar() should return T of int|string but returns T of int.

Full report

PHP 8.0 – 8.1 (1 error)

Line	Error
11	`Function bar() should return T of int

PHP 7.1 – 7.4 (2 errors)

Line	Error
8	Function bar() uses native union types but they're supported only on PHP 8.0 and later.
11	`Function bar() should return T of int

[phpstan-bot]

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

@@ @@
-PHP 8.0 (1 error)
+PHP 8.0
 ==========
 
-11: Function bar() should return T of int|string but returns T of int.
+No errors
 
-PHP 7.1 – 7.4 (2 errors)
+PHP 7.1 – 7.4 (1 error)
 ==========
 
- 8: Function bar() uses native union types but they're supported only on PHP 8.0 and later.
-11: Function bar() should return T of int|string but returns T of int.
+ 8: Function bar() uses native union types but they're supported only on PHP 8.0 and later.

Full report

PHP 8.0

No errors

PHP 7.1 – 7.4 (1 error)

Line	Error
8	Function bar() uses native union types but they're supported only on PHP 8.0 and later.

[phpstan-bot]

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

@@ @@
-PHP 8.0 – 8.1 (3 errors)
+PHP 8.0 – 8.1
 ==========
 
- 8: PHPDoc tag @param for parameter $key with type T of int|string is not subtype of native type int|string.
- 8: PHPDoc tag @return with type T of int|string is not subtype of native type int|string.
-11: Function bar() should return T of int|string but returns T of int.
+No errors
 
-PHP 7.1 – 7.4 (4 errors)
+PHP 7.1 – 7.4 (1 error)
 ==========
 
- 8: Function bar() uses native union types but they're supported only on PHP 8.0 and later.
- 8: PHPDoc tag @param for parameter $key with type T of int|string is not subtype of native type int|string.
- 8: PHPDoc tag @return with type T of int|string is not subtype of native type int|string.
-11: Function bar() should return T of int|string but returns T of int.
+ 8: Function bar() uses native union types but they're supported only on PHP 8.0 and later.

Full report

PHP 8.0 – 8.1

No errors

PHP 7.1 – 7.4 (1 error)

Line	Error
8	Function bar() uses native union types but they're supported only on PHP 8.0 and later.

[szepeviktor]

Thank you.

[szepeviktor]

The PHPStan t-shirt has arrived here 😃

[github-actions]

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.