UI suggestion - add 5 leading spaces to the output string and change the red box to a green battery.

Adding spacing will fix indentation of output to align with the test hierarchy.

Red fuel station looks alarming, changing to a relaxed green battery would look better.

Instead of

      console.log(
        '\x1b' + gasColor,
        `⛽ ${prop} (${gas} gas) ${gas === 69420 ? 'nice.' : ''}`,
      );

change to -

      console.log(
        '\x1b' + gasColor,
        `     🔋 ${prop} (${gas} gas) ${gas === 69420 ? 'nice.' : ''}`,
      );

1/ changed gas usage output to have a static indentation; 2/ replaced alarming red fuel pump with a relaxed bullet, or ⚠️ in case of gasUsed > this.highGasThreshold; 3/ removed text colors, high gas usage doesn't necessarily require red text;

I can't seem to find how to access GasTracker.

The docs only mention to use

require("hardhat-gas-trackooor");

but that doesn't define GasTracker, so looking at the package source code it extends hre

extendEnvironment((hre: HardhatRuntimeEnvironment) => {
  hre.GasTracker = GasTracker;
  hre.GetGas = GetGas;
});

so I tried

require("hardhat-gas-trackooor");
const hre = require("hardhat");
...
test = new hre.GasTracker(await Test.deploy());

but when executed using npx hardhat test it throws TypeError: GasTracker is not a constructor and hre.GasTracker is undefined.

Also tried switching the require lines so that require("hardhat-gas-trackooor"); is after const hre = require("hardhat"); but it didn't help.

Even with your own Greeter example, the resulting object does not have any of its original properties.

TS2339: Property 'setGreeting' does not exist on type 'GasTracker'.