Improve file type extension check in check_upload_mimes() to fix loose check

[Nikschavan]

Trac ticket: https://core.trac.wordpress.org/ticket/50136

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Props nikschavan, ayeshrajans, ayazahmed12, judyeland.

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[judyeland]

What about if we add jpg format as well here its code

'foo', // Added 'jpg' to the list of allowed file extensions 'tx' => 'bar', 't' => 'baz', ]; $allowed_mimes = check_upload_mimes( $mimes ); $this->assertTrue( isset( $allowed_mimes['srt|txt|png|jpg'] ) ); $this->assertTrue( isset( $allowed_mimes['t'] ) ); $this->assertFalse( isset( $allowed_mimes['tx'] ) ); $this->assertFalse( isset( $allowed_mimes['rt'] ) ); $this->assertFalse( isset( $allowed_mimes['xf'] ) ); } } endif;