Psalter: Docblock param descriptions duplicated or removed

[aboyton]

I found two issues when getting Psalter to add/fix parameters into doc blocks (either MissingParamType or MismatchingDocblockParamType, both with safe_types) where the existing param descriptions are either ignored or removed.

I made one issue as these seem related. Happy to split if you prefer.

Issue 1: Param is duplicated

If I have the following code and I run Psalter to add a type in then it duplicates the param in the doc block rather than merging it.

class C {
    /**
     * @param $ab the string you pass in
     */
    public function fooFoo($ab): void {}
}

/**
 * @param string $ab
 */
function callsWithString($ab): void {
    (new C)->fooFoo($ab);
}

is turned into

class C {
    /**
     * @param $ab the string you pass in
     * @param string $ab
     */
    public function fooFoo($ab): void {}
}

/**
 * @param string $ab
 */
function callsWithString($ab): void {
    (new C)->fooFoo($ab);
}

Where as I would hope would be that the docblock would become

/**
 * @param string $ab the string you pass in
 */

Issue 2: Param description removed when fixing incorrect doc block types

Worse, and somewhat relatedly, if Psalter is fixing a return type, it drops the param description entirely.

/**
 * @param int $s the string
 */
function foo(string $s): string {
    return "hello";
}

becomes

/**
 * @param string $s
 */
function foo(string $s): string {
    return "hello";
}

[psalm-github-bot]

Hey @aboyton, can you reproduce the issue on https://psalm.dev ?

[aboyton]

Hey @aboyton, can you reproduce the issue on https://psalm.dev ?

No as it doesn't appear to have the flags that I needed. I did reproduce it in some unit tests in #9441 though :)