Jest coverage is not working properly on docker - linux

Question

I am using JEST for testing a package I am creating and I am using 100% coverage in all aspects.
On windows everything works fine, coverage is 100% as expected but when I run it on a docker even though the node version is the same (14.18.1), jest fails to detect 2 lines of code that I'm am sure that they were reached, here is the code:
import callIf from 'src/tools/call-if';
import zlib from 'zlib';
export default class CompressorEngine {
static preparaData<T>(data: T): Buffer {
const isNullOrUndefined = [null, undefined].includes(data as any);
if (isNullOrUndefined) {
return Buffer.from('null', 'utf-8');
}
return Buffer.from(JSON.stringify(data), 'utf-8');
}
static compress(uncompressedData: Buffer, compressionLevel: number = 9) {
return new Promise<Buffer>((resolve, reject) => {
zlib.deflate(uncompressedData, { level: compressionLevel }, (error, result) => {
callIf(error, reject, error);
callIf(!error, resolve, result);
});
});
}
static decompress(compressedData: Buffer, compressionLevel: number = 9) {
return new Promise<Buffer>((resolve, reject) => {
zlib.inflate(compressedData, { level: compressionLevel }, (error, result) => {
callIf(error, reject, error);
callIf(!error, resolve, result);
});
});
}
}
the src/tools/call-if code:
const callIf = (expression: any, callback: Function, ...args: any[]) => {
if (expression) return callback(...args);
};
export default callIf;
and here are my tests for this class:
import CompressorEngine from 'src/core/compressor';
describe('CompressorEngine', () => {
it('should compress and decompress data', async () => {
const input = 'test';
const compressed = await CompressorEngine.compress(CompressorEngine.preparaData(input));
const uncompressed = await CompressorEngine.decompress(compressed);
expect(uncompressed.toString('utf-8')).toEqual(`"${input}"`);
});
it('should compress and decompress null as "null"', async () => {
const input = null;
const compressed = await CompressorEngine.compress(CompressorEngine.preparaData(input));
const uncompressed = await CompressorEngine.decompress(compressed);
expect(JSON.parse(uncompressed.toString('utf-8'))).toEqual(null);
});
describe('prepareData', () => {
it('should return a buffer for null value as "null"', () => {
Array.prototype.includes = jest.fn(Array.prototype.includes);
const buffer = CompressorEngine.preparaData(null);
expect(buffer.toString('utf-8')).toBe('null');
expect(Array.prototype.includes).toHaveBeenCalled();
expect(Array.prototype.includes).toHaveReturnedWith(true);
});
it('should return a buffer for undefined value as "null"', () => {
const buffer = CompressorEngine.preparaData(undefined);
expect(buffer.toString('utf-8')).toBe('null');
});
});
});
The problem is on prepareData it says as if the if(true) is not reached, but it is as the first prepareData specific test describes "expect(Array.prototype.includes).toHaveReturnedWith(true);" but the generated coverage says it wasn't covered, how come?