fix(expect)!: check more properties for error equality

[hi-ogawa]

Description

• closes toEqual/toStrictEqual does not check custom Error properties #5244
• closes The "cause" property of Error is ignored when matching #5697

NodeJs PR for a reference

• assert: add deep equal check for more Error type nodejs/node#51805

todo

• error equality
• error formatting
• asymmetrically show cause diff
• handle cyclic object
  • it can fail due to chai's error message generation Maximum call stack size exceeded when assertion fails with cyclic references of Error.cause  chaijs/chai#1645 Fixed!
• should we update toThrowError(new Error(...)) usage too? (I think so)
• should we break snapshot too? (for now, new error formatter is applied only when diffing and this looks fine)
• docs

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[sheremet-va]

@hi-ogawa is there anything specific that keeps this PR in draft? Can I help?

[hi-ogawa]

I had a concern about whether we should print diff when custom properties are different. Currently, Vitest cannot show any diff in this case since pretty-format strips it off. Fortunately, chai/loupe can print them, but it's possible that the message will be truncated and not visible to users. This is an example from test cases:

exports[`Error equality > basic 4`] = `
{
  "actual": "[Error: hello]",
  "diff": "Compared values have no visual difference.",
  "expected": "[Error: hello]",
  "message": "expected Error: hello { cause: 'x' } to deeply equal Error: hello { cause: 'y' }",
}
`;

Do you think it's worth changing pretty-format side (I haven't attempted anything yet whether it's possible or not) or just keep it as is and rely on chai error message?

[sheremet-va]

Do you think it's worth changing pretty-format side (I haven't attempted anything yet whether it's possible or not) or just keep it as is and rely on chai error message?

I think we can maybe introduce a flag in pretty-print (or maybe there is already one?) to print Error as an object.

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[sheremet-va]

Can we rewrite it as a bunch of if statements? This is hard to process 😄