Problem with $_ENV

[matiux]

I have this function to take environment variables in various ways

https://psalm.dev/r/084f2df25d

But I'm struggling to figure out how to solve the TypeDoesNotContainType error

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/084f2df25d

<?php

class EnvVarUtil
{
    public static function get(string $name, string $default = ''): string
    {
        return getenv($name) ?: (string) $_ENV[$name] ?? $default;
    }
}

Psalm output (using commit 07c7c30):

ERROR: TypeDoesNotContainType - 7:33 - string is always defined and non-null

[weirdan]

Shouldn't the last ternary be wrapped in parens?
https://psalm.dev/r/f48b8a52dc

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/f48b8a52dc

<?php

class EnvVarUtil
{
    public static function get(string $name, string $default = ''): string
    {
        return getenv($name) ?: (string) ($_ENV[$name] ?? $default);
    }
}

Psalm output (using commit 07c7c30):

No issues!

[matiux]

Thanks, I hadn't considered this syntax and actually don't understand why in this way works.

[muglug]

It's about operator precedence – when in doubt, parenthesize

[matiux]

@muglug some updates lead me to reopen this issue https://psalm.dev/r/f48b8a52dc

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/f48b8a52dc

<?php

class EnvVarUtil
{
    public static function get(string $name, string $default = ''): string
    {
        return getenv($name) ?: (string) ($_ENV[$name] ?? $default);
    }
}

Psalm output (using commit d0be59e):

ERROR: PossiblyInvalidCast - 7:43 - non-empty-list<string> cannot be cast to string

[weirdan]

@matiux please open a new issue.

It appears someone thought $_ENV usually contains argv element, like $_SERVER does:

psalm/src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/VariableFetchAnalyzer.php

Lines 674 to 707 in d0be59e

	if ($var_id === '$_SERVER' || $var_id === '$_ENV') {
	$string_helper = Type::getString();
	$string_helper->possibly_undefined = true;
	$non_empty_string_helper = Type::getNonEmptyString();
	$non_empty_string_helper->possibly_undefined = true;
	$argv_helper = new Union([
	new TNonEmptyList(Type::getString())
	]);
	$argv_helper->possibly_undefined = true;
	$argc_helper = new Union([
	new TIntRange(1, null)
	]);
	$argc_helper->possibly_undefined = true;
	$request_time_helper = new Union([
	new TIntRange(time(), null)
	]);
	$request_time_helper->possibly_undefined = true;
	$request_time_float_helper = Type::getFloat();
	$request_time_float_helper->possibly_undefined = true;
	$bool_string_helper = new Union([new TBool(), new TString()]);
	$bool_string_helper->possibly_undefined = true;
	$detailed_type = new TKeyedArray(
	[
	// https://www.php.net/manual/en/reserved.variables.server.php
	'PHP_SELF' => $non_empty_string_helper,
	'argv' => $argv_helper,
	'argc' => $argc_helper,