cue: resolve a few staticcheck warnings

Instance's setError and eval methods are unexported and unused.
Moreover, Instance itself has been deprecated for years.

hasDisjunction and stripNonDefaults, as well as their uses in the
commented-out bit of code in Value.Default,
have been unused for at least four years. They are still present
in the git history if needed, but clearly they are not needed now
and have not actually been for a long time already.

Finally, rewrite the way a test advances an iterator twice
so that it doesn't make staticcheck think that we mistakenly
checked the same condition twice, which is often due to human error.

Updates #3335.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: If6608b5d9d1076316e3c03e530b6b6577a157605
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1202602
Reviewed-by: Roger Peppe <[email protected]>
TryBot-Result: CUEcueckoo <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>

Author: mvdan

cue/instance.go

@@ -165,17 +165,6 @@ func (inst *Instance) setListOrError(err errors.Error) {
 	inst.Err = errors.Append(inst.Err, err)
 }
 
-func (inst *Instance) setError(err errors.Error) {
-	inst.Incomplete = true
-	inst.Err = errors.Append(inst.Err, err)
-}
-
-func (inst *Instance) eval(ctx *adt.OpContext) adt.Value {
-	// TODO: remove manifest here?
-	v := manifest(ctx, inst.root)
-	return v
-}
-
 // ID returns the package identifier that uniquely qualifies module and
 // package name.
 func (inst *Instance) ID() string {

cue/types.go

@@ -719,133 +719,6 @@ func (v Value) Default() (Value, bool) {
 		return v, false
 	}
 	return makeValue(v.idx, d, v.parent_), true
-
-	// d, ok := v.v.Value.(*adt.Disjunction)
-	// if !ok {
-	// 	return v, false
-	// }
-
-	// var w *adt.Vertex
-
-	// switch d.NumDefaults {
-	// case 0:
-	// 	return v, false
-
-	// case 1:
-	// 	w = d.Values[0]
-
-	// default:
-	// 	x := *v.v
-	// 	x.Value = &adt.Disjunction{
-	// 		Src:         d.Src,
-	// 		Values:      d.Values[:d.NumDefaults],
-	// 		NumDefaults: 0,
-	// 	}
-	// 	w = &x
-	// }
-
-	// w.Conjuncts = nil
-	// for _, c := range v.v.Conjuncts {
-	// 	// TODO: preserve field information.
-	// 	expr, _ := stripNonDefaults(c.Expr())
-	// 	w.AddConjunct(adt.MakeConjunct(c.Env, expr))
-	// }
-
-	// return makeValue(v.idx, w), true
-
-	// if !stripped {
-	// 	return v, false
-	// }
-
-	// n := *v.v
-	// n.Conjuncts = conjuncts
-	// return Value{v.idx, &n}, true
-
-	// isDefault := false
-	// for _, c := range v.v.Conjuncts {
-	// 	if hasDisjunction(c.Expr()) {
-	// 		isDefault = true
-	// 		break
-	// 	}
-	// }
-
-	// if !isDefault {
-	// 	return v, false
-	// }
-
-	// TODO: record expanded disjunctions in output.
-	// - Rename Disjunction to DisjunctionExpr
-	// - Introduce Disjuncts with Values.
-	// - In Expr introduce Star
-	// - Don't pick default by default?
-
-	// Evaluate the value.
-	// 	x := eval.FinalizeValue(v.idx.Runtime, v.v)
-	// 	if b, _ := x.Value.(*adt.Bottom); b != nil { // && b.IsIncomplete() {
-	// 		return v, false
-	// 	}
-	// 	// Finalize and return here.
-	// 	return Value{v.idx, x}, isDefault
-}
-
-// TODO: this should go: record preexpanded disjunctions in Vertex.
-func hasDisjunction(expr adt.Expr) bool {
-	switch x := expr.(type) {
-	case *adt.DisjunctionExpr:
-		return true
-	case *adt.Conjunction:
-		for _, v := range x.Values {
-			if hasDisjunction(v) {
-				return true
-			}
-		}
-	case *adt.BinaryExpr:
-		switch x.Op {
-		case adt.OrOp:
-			return true
-		case adt.AndOp:
-			return hasDisjunction(x.X) || hasDisjunction(x.Y)
-		}
-	}
-	return false
-}
-
-// TODO: this should go: record preexpanded disjunctions in Vertex.
-func stripNonDefaults(expr adt.Expr) (r adt.Expr, stripped bool) {
-	switch x := expr.(type) {
-	case *adt.DisjunctionExpr:
-		if !x.HasDefaults {
-			return x, false
-		}
-		d := *x
-		d.Values = []adt.Disjunct{}
-		for _, v := range x.Values {
-			if v.Default {
-				d.Values = append(d.Values, v)
-			}
-		}
-		if len(d.Values) == 1 {
-			return d.Values[0].Val, true
-		}
-		return &d, true
-
-	case *adt.BinaryExpr:
-		if x.Op != adt.AndOp {
-			return x, false
-		}
-		a, sa := stripNonDefaults(x.X)
-		b, sb := stripNonDefaults(x.Y)
-		if sa || sb {
-			bin := *x
-			bin.X = a
-			bin.Y = b
-			return &bin, true
-		}
-		return x, false
-
-	default:
-		return x, false
-	}
 }
 
 // Label reports he label used to obtain this value from the enclosing struct.

cue/types_test.go

@@ -3324,10 +3324,12 @@ func TestPathCorrection(t *testing.T) {
 			if !i.Next() {
 				t.Fatal("no fields")
 			}
-			// Locate b
+			// Locate b, the second field
 			i, _ = i.Value().Fields(cue.Definitions(true), cue.Optional(true))
-			if !(i.Next() && i.Next()) {
-				t.Fatal("no fields")
+			for range 2 {
+				if !i.Next() {
+					t.Fatal("no fields")
+				}
 			}
 			v := i.Value()
 			return v