2

Assume I have two contracts:

contract A {
    function test1() public view returns(bool) {
        return false;
    }
}
contract B {
    function testCall(address addr, data) public view returns(bool) {
        return addr.call.value(0)(data);
    }
}

Then I call testCall in javascript:

const a = await A.new()
const b = await B.new()

const aWeb3 = web3.eth.contract(a.abi)
const aInstance = aWeb3.at(a.address)

const testData = aInstance.test1.getData()

const ans = await bInstance.testCall(aInstance.address, testData)

console.log(ans)

In this case, ans should be false, but it returns true

1

The addr.call type call returns true on success and false otherwise. To get the actual return value you need to either use the high-level contract interface system or use assembly like

assembly{
    let success := call(10000, addr, 0, add(data, 0x20), mload(data), 0, 0x20)
    res := mload(0)
 }
return res

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