go-testinglisted

# Go Testing Guidelines for writing clear, maintainable Go tests following Google's style. ## Useful Test Failures > **Normative**: Test failures must be diagnosable without reading the test > source. Every failure message should include: - What caused the failure - The function inputs - The actual result (got) - The expected result (want) ### Failure Message Format Use the standard format: `YourFunc(%v) = %v, want %v` ```go // Good: if got := Add(2, 3); got != 5 { t.Errorf("Add(2, 3) = %d, want %d", got, 5) } // Bad: Missing function name and inputs if got := Add(2, 3); got != 5 { t.Errorf("got %d, want %d", got, 5) } ``` ### Got Before Want Always print actual result before expected: ```go // Good: t.Errorf("Parse(%q) = %v, want %v", input, got, want) // Bad: want/got reversed t.Errorf("Parse(%q) want %v, got %v", input, want, got) ``` --- ## No Assertion Libraries > **Normative**: Do not create or use assertion libraries. Assertion libraries fragment the developer experience and often produce unhelpful failure messages. ```go // Bad: assert.IsNotNil(t, "obj", obj) assert.StringEq(t, "obj.Type", obj.Type, "blogPost") assert.IntEq(t, "obj.Comments", obj.Comments, 2) // Good: Use cmp package and standard comparisons want := BlogPost{ Type: "blogPost", Comments: 2, Body: "Hello, world!", } if diff := cmp.Diff(want, got); diff != "" { t.Errorf("GetPost() mismatch (-want +got):\n%s", diff) } ``` For domain-specific comparisons,