String

var target = "Homer";
target.ShouldBe("Bart");

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Exception

target
    should be
"Bart"
    but was
"Homer"
    difference
Expected: "Bart"
Actual:   "Homer"

A note on alignment. The ▼/▲ markers point at the differing grapheme clusters using estimated terminal widths. On terminals or fonts that render emoji, CJK, or other wide characters at different widths than expected, markers may shift by a column. When the difference involves a combining mark, zero-width character, flag emoji, or right-to-left script, a Difference at index N: U+XXXX vs U+YYYY line is appended so the codepoints are unambiguous regardless of how your terminal renders the glyphs.

ShouldNotBe

var target = "Bart";
target.ShouldNotBe("Bart");

^{snippet source | anchor}

Exception

target
    should not be
"Bart"
    but was