Testing And Benchmarking in Pascal

Here’s the translation of the Go testing and benchmarking example to Pascal, formatted in Markdown suitable for Hugo:

In Pascal, unit testing is typically done using frameworks like DUnit or FPCUnit. For this example, we’ll use a simplified approach to demonstrate the concepts.

program TestingAndBenchmarking;

uses
  SysUtils;

function IntMin(a, b: Integer): Integer;
begin
  if a < b then
    Result := a
  else
    Result := b;
end;

procedure TestIntMinBasic;
var
  ans: Integer;
begin
  ans := IntMin(2, -2);
  if ans <> -2 then
    WriteLn('Error: IntMin(2, -2) = ', ans, '; want -2');
end;

type
  TTestCase = record
    a, b: Integer;
    want: Integer;
  end;

procedure TestIntMinTableDriven;
var
  tests: array[0..4] of TTestCase = (
    (a: 0; b: 1; want: 0),
    (a: 1; b: 0; want: 0),
    (a: 2; b: -2; want: -2),
    (a: 0; b: -1; want: -1),
    (a: -1; b: 0; want: -1)
  );
  i: Integer;
  ans: Integer;
begin
  for i := 0 to High(tests) do
  begin
    ans := IntMin(tests[i].a, tests[i].b);
    if ans <> tests[i].want then
      WriteLn('Error: IntMin(', tests[i].a, ', ', tests[i].b, ') = ', ans, '; want ', tests[i].want);
  end;
end;

procedure BenchmarkIntMin;
var
  startTime, endTime: TDateTime;
  i, iterations: Integer;
begin
  iterations := 1000000; // Adjust this number based on your system's performance
  startTime := Now;
  for i := 1 to iterations do
    IntMin(1, 2);
  endTime := Now;
  WriteLn('BenchmarkIntMin: ', iterations, ' iterations in ',
          FormatDateTime('s.zzz', endTime - startTime), ' seconds');
end;

begin
  WriteLn('Running tests...');
  TestIntMinBasic;
  TestIntMinTableDriven;
  WriteLn('Tests completed.');
  
  WriteLn('Running benchmark...');
  BenchmarkIntMin;
  WriteLn('Benchmark completed.');
end.

This Pascal program demonstrates basic concepts of testing and benchmarking. Here’s a breakdown of the code:

1. We define the IntMin function, which is the function we want to test.

2. TestIntMinBasic is a simple test function that checks a single case.

3. TestIntMinTableDriven demonstrates a table-driven test approach. We define a series of test cases and loop through them.

4. BenchmarkIntMin is a simple benchmark function that runs the IntMin function multiple times and measures the execution time.

To run the tests and benchmark:

$ fpc TestingAndBenchmarking.pas
$ ./TestingAndBenchmarking
Running tests...
Tests completed.
Running benchmark...
BenchmarkIntMin: 1000000 iterations in 0.016 seconds
Benchmark completed.

Note that Pascal doesn’t have built-in testing or benchmarking frameworks like Go does. In a real-world scenario, you would typically use a testing framework like DUnit or FPCUnit for more robust testing capabilities.

Also, the benchmarking approach used here is very simplistic. In a more sophisticated setup, you might want to run the benchmark multiple times and calculate average performance, or use more advanced timing mechanisms for more precise measurements.

Remember that while this example demonstrates the concepts, it’s not a direct equivalent to Go’s testing package. Pascal developers often use different patterns and tools for testing and benchmarking their code.