table_test.go

package merge

import (
        "testing"
)

func TestMergeTables(t *testing.T) {
        alice := Table[string, *additive]{
                "vanilla": add(3),
                "chocolate": add(5),
                "strawberry": add(2),
        }

        bob := Table[string, *additive]{
                "vanilla": add(2),
                "chocolate": add(3),
                "pistacchio": add(5),
        }

        votes := make(Table[string, *additive])
        if err := votes.Merge(alice); err != nil {
                t.Fatalf("tables failed to merge: %v", err)
        }
        if err := votes.Merge(bob); err != nil {
                t.Fatalf("tables failed to merge: %v", err)
        }

        check := func(k string, n int) {
                if have := votes[k].total; have != n {
                        t.Fatalf("expected %d votes for %s but saw %v instead", n, k, have)
                }
        }
        check("vanilla", 5)
        check("chocolate", 8)
        check("strawberry", 2)
        check("pistacchio", 5)

        bob["pistacchio"].Merge(add(100))
        bob["pistacchio"] = add(1)
        check("pistacchio", 5)
}