Regression with RedundantConditionGivenDocblockType and DocblockTypeContradiction

[ArtemGoutsoul]

Psalm incorrectly reports truthy and falsy values, and marks a redundant check or a doc type contradiction:

This broke in 5.19.1 I think

Consider:

/**
 * @param array<string, true> $array
 */
function func(array $array): int
{
    if (!empty($array['stuff'])) return 1;
    
    if (empty($array['more stuff'])) return 2;

    return 3;
}

Psalm returns:

Psalm output (using commit [c488d40](https://github.com/vimeo/psalm/commit/c488d40)): 

ERROR: [RedundantConditionGivenDocblockType](https://psalm.dev/156) - 8:6 - Operand of type true is always truthy

ERROR: [DocblockTypeContradiction](https://psalm.dev/155) - 10:9 - Operand of type false is always falsy

https://psalm.dev/r/892d59e94e

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/892d59e94e

<?php

/**
 * @param array<string, true> $array
 */
function func(array $array): int
{
	if (!empty($array['stuff'])) return 1;
    
    if (empty($array['more stuff'])) return 2;
    return 3;
}

Psalm output (using commit c488d40):

ERROR: RedundantConditionGivenDocblockType - 8:6 - Operand of type true is always truthy

ERROR: DocblockTypeContradiction - 10:9 - Operand of type false is always falsy

[ArtemGoutsoul]

Possibly related: #10716

[kkmuffme]

If you enable https://psalm.dev/docs/running_psalm/configuration/#ensurearraystringoffsetsexist in your config, do you still get this error?

[ArtemGoutsoul]

@kkmuffme well, the default setting for ensureArrayStringOffsetsExist is false, so when I set it to true, I only get new errors, no existing errors get removed (saved reports and made a diff).

So these RedundantConditionGivenDocblockType and DocblockTypeContradiction errors are not affected by ensureArrayStringOffsetsExist setting.

Would have been cool to be able to change the config attributes in the paslm.dev playground :)

[weirdan]

Would have been cool to be able to change the config attributes in the paslm.dev playground :)

You can change some of them by clicking the Settings button.

[ArtemGoutsoul]

@weirdan yup! would be cool to have the rest of them (with their config names). This way it would be easier to reproduce some test cases, or even better a text area to paste a config! and a version selector for regression reproduction!

but that's totally off-topic :)

[kkmuffme]

It's a bug bc of the true values - works fine with isset https://psalm.dev/r/6de6380bf7

Possibly the issue happens from https://github.com/vimeo/psalm/blob/5.x/src/Psalm/Internal/Analyzer/Statements/Expression/EmptyAnalyzer.php#L62 and below
I would check if it's reporting as possibly undefined for line 62 or not and see from there.

Give it a shot for a PR and report back if you need any help.

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/6de6380bf7

<?php

/**
 * @param array<string, true> $array
 */
function func(array $array): int
{
	if (isset($array['stuff'])) return 1;
    
    if (!isset($array['more stuff'])) return 2;
    return 3;
}

Psalm output (using commit b940c7e):

No issues!

[weirdan]

I would check if it's reporting as possibly undefined for line 62 or not and see from there.

It's not. It's been discussed in more details here: #10578 (comment)

[ArtemGoutsoul]

@weirdan oops, didn't notice #10578

It feels like this issue is a duplicate of that one.

[weirdan]

Most likely it is, but I've no problem to keep both open until we figure out this for sure