Update documentation for the Error function in assert or require package

[architagr]

Summary

Incorrect assert.Error() docs

Changes

Removing the if statement and the Equal call from the example.

Motivation

Since we already have EqualError, the documentation is trying to use assert.Equal to assert the error object's content.

Related issues

Closes #1609

[dolmen]

The change now hides that Error returns a boolean that can be used for further checks.

I think that we must keep the if statement around in the usage example.

[architagr]

The change now hides that Error returns a boolean that can be used for further checks.

I think that we must keep the if statement around in the usage example.

This change is in accordance with the below conversation by @brackendawson

#1609 (comment)

[alexandear]

Maybe better would be the following:

Suggested change

	// actualObj, err := SomeFunction()
	// assert.Error(t, err)
	// actualObj, err := SomeFunction()
	// if assert.Error(t, err) {
	// assert.Equal(t, expectedObj, actualObj)
	// }

In that case, we don't hide that Equals returns boolean.

[brackendawson]

This is not good practice IMO, a good test will check the returned actualObj even if the returned error is non-nil.

[brackendawson]

I approve as is.

This was a poor place to document the assert assertions returning a booleans. It's just one assertion out of many. Perhaps one of the examples at the top of the package should be used.

It's important to remove this from the assert.Error doc because it is also used as the require.Error doc, which does not return a boolean! The only alternative is writing some code in the generator to handle it.

I also think the example is a bad example because the inner assert.Equal can stand in place of the entire example.