updates on the order bulk fix

internal/assignment/balance_test.go

@@ -0,0 +1,59 @@
+package assignment
+
+import (
+	"testing"
+
+	"doormile/models"
+)
+
+func cand(id int, inHand, session int64, km, rating float64) *milerCandidate {
+	return &milerCandidate{
+		profile:        models.MilerProfile{Userid: id, Rating: rating},
+		distanceKm:     km,
+		activeBookings: inHand,
+		sessionStops:   session,
+	}
+}
+
+// The balancing order: in hand, then this session, then distance, then rating.
+func TestPickBestBalancesBeforeDistance(t *testing.T) {
+	cases := []struct {
+		name string
+		in   []*milerCandidate
+		want int
+	}{
+		{"fewer in hand beats nearer", []*milerCandidate{cand(1, 2, 0, 0.2, 5), cand(2, 1, 9, 9.0, 1)}, 2},
+		{"tie in hand: fewer this session", []*milerCandidate{cand(1, 1, 5, 0.2, 5), cand(2, 1, 2, 4.0, 3)}, 2},
+		{"tie in hand and session: nearer", []*milerCandidate{cand(1, 1, 2, 3.0, 5), cand(2, 1, 2, 1.0, 3)}, 2},
+		{"full tie: better rating", []*milerCandidate{cand(1, 1, 2, 1.0, 4.1), cand(2, 1, 2, 1.0, 4.8)}, 2},
+		{"single candidate", []*milerCandidate{cand(7, 3, 3, 3, 3)}, 7},
+	}
+	for _, c := range cases {
+		if got := pickBestFromCandidates(c.in); got == nil || got.profile.Userid != c.want {
+			t.Errorf("%s: got %v, want rider %d", c.name, got, c.want)
+		}
+	}
+	if pickBestFromCandidates(nil) != nil {
+		t.Error("no candidates must give nil")
+	}
+}
+
+// leastLoaded keeps only the riders with the fewest in hand, with their
+// parallel AI rows.
+func TestLeastLoaded(t *testing.T) {
+	cs := []*milerCandidate{cand(1, 2, 0, 1, 4), cand(2, 0, 0, 2, 4), cand(3, 1, 0, 3, 4), cand(4, 0, 5, 4, 4)}
+	ai := []aiCandidate{{MilerID: 1}, {MilerID: 2}, {MilerID: 3}, {MilerID: 4}}
+	gotC, gotAI := leastLoaded(cs, ai)
+	if len(gotC) != 2 || gotC[0].profile.Userid != 2 || gotC[1].profile.Userid != 4 {
+		t.Fatalf("least loaded = %v", gotC)
+	}
+	if len(gotAI) != 2 || gotAI[0].MilerID != 2 || gotAI[1].MilerID != 4 {
+		t.Fatalf("AI rows must follow: %v", gotAI)
+	}
+	if c, a := leastLoaded(nil, nil); len(c) != 0 || len(a) != 0 {
+		t.Fatal("empty in, empty out")
+	}
+	if c, _ := leastLoaded(cs, nil); len(c) != 2 {
+		t.Fatal("AI rows are optional")
+	}
+}