What a brew-haha!

Chaos erupted outside a popular Brooklyn brewery Friday night, when an apparently annoyed craft-beer hater pulled a gun on a long line of people who were waiting to buy the latest designer IPA, according to cops and online reports.

No shots were fired during the squabble outside the Other Half Brewing Company in Carroll Gardens — and a suspect was being questioned Saturday, police said.

The gun-slinging skeptic struck around the corner from the brewery, on Garnet Street, where beer lovers with camp chairs and hand trucks regularly line up overnight to buy limited-run, $18 four-packs in collectible cans, sold when the doors open Saturday mornings.

It was at around 9 p.m. when the gunman and a woman he was with allegedly confronted the long line of hops hipsters.

“We’re hanging out, the line was going around the block at that point,” remembered one witness, a 27-year-old Manhattan software engineer who asked to not be named.

“We were just chatting, not really doing anything. It was a dude and a woman. I think they were drunk.”

The pair, who were staying at a short-term apartment rental at 39 Garnet St., began mocking the beer-lovers for standing online overnight for the release of 10 beers, with names like Bourbon Barrel Aged Bananaversary Imperial Stout, and All 6th Anniversary Everything Chocolate Peanut Butter Crunchee Imperial Stout.

First the taunts flew, then some of the camp chairs, the witness said.

The belligerent couple disappeared back into the apartment building.

Soon afterward, the man came back outside to glare at the line again. He began drinking a can of White Claw hard seltzer — which may have been just another taunt — and “just talking a bunch of s–t,” the witness said.

“So we talked some s–t back,” the witness said.

“The guy was telling us we were a bunch of idiots waiting online for beer, so I said, ‘Oh what, is this the only Airbnb you can afford?’

“Then he got super pissed and threw a White Claw at us, which was the funniest part of the night.”

A woman on the line dodged the flying, inferior can, then yelled, “Why are you throwing beers at a girl? That’s not cool, man!”

“And then he goes, ‘OK, well how about I put a Glock in your mouth?'” the witness said.

“Then he just walked inside,” the witness said. “Nobody thought he would actually have a gun, because who the hell would bring out a gun over something this stupid?”

Five minutes later, the man came back out, gun in hand.

“He said it was a Glock 19,” the witness said.

“At that point, we de-escalated the situation. And he put it away and went inside.”

The pro-craft beer folks promptly called the cops on the anti-craft beer gunman.

“Thirty seconds later, like eight cop cars come down.”

The last the beer-lovers saw of the gunman was when cops hauled him out of the apartment building in handcuffs. The folks on line confirmed his identity, and cops took him away.

“He looked average, honestly. He just looked like a regular white guy with a beard,” the witness said, guessing his age was around 30, and that he was from somewhere in the Midwest.

A worker at the brewery said on rare occasions, a fight may break out on the beer line, but he’s never heard of a gun being pulled before Friday night.

“He didn’t even flee the scene or anything!” the worker said, astonished. “He just hung out at the Airbnb.”

Airbnb said it did not rent out the apartment but a competing company may have.

Police did not immediately have arrest information available.