all: resolve a few more staticcheck warnings

Continuing to slowly chip away at these where it makes sense,
rather than big sweeping changes which are hard to review
and sure to cause conflicts.

None of the changes below change behavior in any way;
they only remove unused code or simplify code.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: I19b063f8b0d3dac2e80be88af295937dbf7dc255
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1202112
Reviewed-by: Roger Peppe <[email protected]>
TryBot-Result: CUEcueckoo <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>

cue/interpreter/wasm/call.go

@@ -74,11 +74,7 @@ func encNumber(typ cue.Value, val cue.Value) (r uint64) {
 }
 
 func decBool(v uint64) bool {
-	u := api.DecodeU32(v)
-	if u == 1 {
-		return true
-	}
-	return false
+	return api.DecodeU32(v) == 1
 }
 
 // decNumber decodes the the Wasm/System V ABI encoding of the

encoding/openapi/build.go

@@ -56,11 +56,6 @@ type buildContext struct {
 	// TODO: consider an option in the CUE API where optional fields are
 	// recursively evaluated.
 	cycleNodes []*adt.Vertex
-
-	// imports caches values as returned by cue.Value.ReferencePath
-	// for use by ReferenceFunc. It's only initialised when ReferenceFunc
-	// is non-nil.
-	imports map[cue.Value]*cue.Instance
 }
 
 type externalType struct {

internal/core/adt/disjunct2.go

@@ -578,15 +578,6 @@ outer:
 	return append(a, x)
 }
 
-// isPartialNode reports whether a node must be evaluated as a partial node.
-func isPartialNode(d *nodeContext) bool {
-	if d.node.status == finalized {
-		return true
-	}
-	// TODO: further optimizations
-	return false
-}
-
 // findIntersections reports the closeContext, relative to the two given
 // disjunction holds, that should be used in comparing the arc set.
 // x and y MUST both be originating from the same disjunct hole. This ensures

internal/core/adt/eval.go

@@ -54,8 +54,6 @@ func (c *OpContext) Stats() *stats.Counts {
 // 	return e.NewContext(v)
 // }
 
-var structSentinel = &StructMarker{}
-
 var incompleteSentinel = &Bottom{
 	Code: IncompleteError,
 	Err:  errors.Newf(token.NoPos, "incomplete"),
@@ -1582,7 +1580,6 @@ type envList struct {
 	id      CloseInfo
 	ignore  bool // has a self-referencing comprehension and is postponed
 	self    bool // was added as a postponed self-referencing comprehension
-	index   int
 }
 
 type envCheck struct {
@@ -2517,8 +2514,8 @@ outer:
 			IsOpen: isOpen,
 		})
 	} else {
-		if expr, _ := m.Src.(ast.Expr); expr != nil {
-			sources = append(sources, expr)
+		if m.Src != nil {
+			sources = append(sources, m.Src)
 		}
 		m.Src = ast.NewBinExpr(token.AND, sources...)
 		m.IsOpen = m.IsOpen && isOpen

internal/core/adt/eval_test.go

@@ -268,7 +268,7 @@ func TestX(t *testing.T) {
 		LogEval: 1,    // Uncomment to turn logging off
 	}
 
-	var version internal.EvaluatorVersion
+	version := internal.DefaultVersion
 	version = internal.DevVersion // comment to use default implementation.
 
 	in := `

internal/core/adt/export_test.go

@@ -91,7 +91,7 @@ func (x *FieldTester) Def(sub ...declaration) declaration {
 func (x *FieldTester) spawn(t closeNodeType, sub ...declaration) declaration {
 	return func(cc *closeContext) {
 		ci := CloseInfo{cc: cc}
-		ci, dc := ci.spawnCloseContext(x.n.ctx, t)
+		_, dc := ci.spawnCloseContext(x.n.ctx, t)
 
 		dc.incDependent(x.n.ctx, TEST, nil)
 		for _, sfn := range sub {

internal/core/adt/sched_test.go

@@ -181,9 +181,6 @@ func TestScheduler(t *testing.T) {
 
 		log   string // A lot
 		state string // A textual representation of the task state
-
-		// err holds all errors or "" if none.
-		err string
 	}
 
 	cases := []testCase{{