[1.0.0] pump pulling in fluid that does not match destination

[-DeadlyKitten]

a pump pulls in fluid that it does not have a hope of putting in the destination due to the destination due to having a different type of fluid
easy to work around in this case but could potentially be a hard problem to diagnose in the case of a contaminated fluid line,

Screenshot 1: Real example of issue (highlighted pump contains light oil)

Screenshot 2020-10-26 185344.png (249.28 KiB) Viewed 1086 times

Reproduction:
1) create the thing in screenshot 2 (blueprint 1)
2) remove the Infinity pipes
3) Place blueprint 2 over the top to connect pipes (screenshot 3)
4) observe that the fluid from the first tank does not flow into the 2nd tank due to light oil in the pump
4b) observe also that if you do not know about this issue (or that the pump color shows its fluid) this would be very difficult to fix

I expected it to not pull in fluid unless the output was the same type of fluid or was empty

edit: forgot screenshots and blueprints

screenshot 2

Screenshot 2020-10-26 194923.png (105.89 KiB) Viewed 1086 times

screenshot 3

Screenshot 2020-10-26 194938.png (89.43 KiB) Viewed 1086 times

blueprint 1:
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

blueprint 2:
0eNqNld1ugzAMhV9l8jVUBAh/l3uNaarS1kPRIKAkVKsq3n0ObG21tfMu4/h8OYEj5wy7bsLRauOhOYPeD8ZB83IGp1ujulDzpxGhgaO2fqJKBEb1obB2xCnMEWhzwA9oxPwaARqvvcYVsyxOWzP1O7TUcFFr86YNbcWjJnwE4+BINZhwIpHibCMjOEGTiY1cDljbtw6916Z1oe8LNaK3Q4dTH7fKBRTaPZ2rWlwO9NhTRfnJ0jolaj8cgkz5uEPlPMxz9MtoejH6wF966+8OIOMAggHkHCBhAJIBcPqC0XMXKBl9xugrRs/9gZrRS0YvEgaQcwDBAAoOwKWw5ABcCisOwKWw5gBcCgUXQ8HmkAuiuEni1I9/ETIaNQdtcb/u5vdo11w6P1iaMrFX5v2PfMkHtup/gq6fSC6z8MZgem90Jcx1qxVW/IQVYXprGpekvL4KEXRqh/QSwPN37Sml6hGtWz1UIi/zuixKkRSymOdPJfgD8A==

[valneq]

I expected it to not pull in fluid unless the output was the same type of fluid or was empty

I have the vague impression that your expectation does not necessarily match with the way Wube has simplified the fluid-mixing prevention systems.
An explanation here (scroll down to the third section "Fluid Mixing Prevention - take 9001"):
https://factorio.com/blog/post/fff-351

[edit] PS: If you experience temporary fluid mixture due to reworking you pipes, you can always click on a pipe or storage tank and check the fluid content of the entire pipe system and flush the polluting fluid. If the mixture is permanent you will have to fix the pipes that incorrectly connect different fluid systems first.

[Squelch]

It is entirely possible to have a multi-fluid system, but a few tricks have to be played to isolate one fluid network from another. What you are attempting to do is fraught with problems as you have discovered. As said, the fluid mixing problems are much improved,and I do not believe that what you are experiencing in this, and the other report are bugs.

[-DeadlyKitten]

the point about stuck fluids is mostly for new players that do not already know about the quick-remove feature, the part i care about is that this would allow fluid un-mixing, as currently that is very difficult due to viewtopic.php?f=47&t=90742, this would allow a way to un-mix fluids without the large bank of combinators you would need to do something like this using the current system

an example mixed fluid system that currently is not posable without moded pieces of equipment

Screenshot 2020-10-26 210638.png (603.99 KiB) Viewed 1063 times

the pump does not activate because the tank has 0.9 fluid so the circuit network cannot read it

[Koub]

[Koub] Moved to Not a bug. The devs have explained several times that they added the "empty fluid" mechanism AND simplified a lot the checks to prevent fluid mixing on purpose. Now, there are many more ways to get fluids mixed when building stuff (with blueprints for example). The solution is to empty the fluids.