Fix identified linter errors preventing errorlint, exhaustive, inamedparam, and staticcheck from running and enable those checks.

.golangci.yml

@@ -4,10 +4,10 @@ linters:
     # Commented entries here are not enabled by default, but that we should
     # add once the relevant lines are fixed up.
 
-    # - errorlint # found 2 cases to be fixed.
-    # - exhaustive # found some cases that should be fixed.
+    - errorlint
+    - exhaustive
     # - exhaustruct # found some structs which missed fields in initializing.
-    # - inamedparam  # fix missing named param
+    - inamedparam
     # - makezero  # fix the unallocated elements.
     # - misspell  # fix spelling
     # - nlreturn  # fix these missing blank line
@@ -68,8 +68,6 @@ linters:
     # Triggers on most tests for failing to call paralleltest.
     # We don't have a need to use this so keep it disabled.
     - paralleltest 
-    # Enable once outstanding lint bugs are fixed.
-    - staticcheck   
     # This triggers on every _test file saying they should be separate
     # parallel packages e.g. s2->s2_test package. We do not plan to ever
     # reshuffle the tests into a separate package.

r3/vector.go

@@ -108,7 +108,7 @@ func (v Vector) Ortho() Vector {
 		ov.Z = 1
 	case YAxis:
 		ov.X = 1
-	default:
+	case ZAxis:
 		ov.Y = 1
 	}
 	return v.Cross(ov).Normalize()

s2/cap.go

@@ -109,7 +109,7 @@ func FullCap() Cap {
 
 // IsValid reports whether the Cap is considered valid.
 func (c Cap) IsValid() bool {
-	return c.center.Vector.IsUnit() && c.radius <= s1.StraightChordAngle
+	return c.center.IsUnit() && c.radius <= s1.StraightChordAngle
 }
 
 // IsEmpty reports whether the cap is empty, i.e. it contains no points.
@@ -391,7 +391,7 @@ func (c Cap) intersects(cell Cell, vertices [4]Point) bool {
 	sin2Angle := c.radius.Sin2()
 	for k := 0; k < 4; k++ {
 		edge := cell.Edge(k).Vector
-		dot := c.center.Vector.Dot(edge)
+		dot := c.center.Dot(edge)
 		if dot > 0 {
 			// The center is in the interior half-space defined by the edge. We do not need
 			// to consider these edges, since if the cap intersects this edge then it also

s2/cap_test.go

@@ -487,7 +487,7 @@ func TestCapContainsCell(t *testing.T) {
 			if got, want := covering.ContainsCell(rootCell), capFace == face; got != want {
 				t.Errorf("Cap(%v).ContainsCell(%v) = %t; want = %t", covering, rootCell, got, want)
 			}
-			if got, want := covering.ContainsCell(edgeCell), center.Vector.Dot(edgeCell.id.Point().Vector) > 0.1; got != want {
+			if got, want := covering.ContainsCell(edgeCell), center.Dot(edgeCell.id.Point().Vector) > 0.1; got != want {
 				t.Errorf("Cap(%v).ContainsCell(%v) = %t; want = %t", covering, edgeCell, got, want)
 			}
 			if got, want := covering.ContainsCell(edgeCell), covering.IntersectsCell(edgeCell); got != want {
@@ -552,7 +552,7 @@ func TestCapIntersectsCell(t *testing.T) {
 			if got, want := covering.IntersectsCell(edgeCell), covering.ContainsCell(edgeCell); got != want {
 				t.Errorf("Cap(%v).IntersectsCell(%v) = %t; want = %t", covering, edgeCell, got, want)
 			}
-			if got, want := covering.IntersectsCell(cornerCell), center.Vector.Dot(cornerCell.id.Point().Vector) > 0; got != want {
+			if got, want := covering.IntersectsCell(cornerCell), center.Dot(cornerCell.id.Point().Vector) > 0; got != want {
 				t.Errorf("Cap(%v).IntersectsCell(%v) = %t; want = %t", covering, cornerCell, got, want)
 			}
 
@@ -561,7 +561,7 @@ func TestCapIntersectsCell(t *testing.T) {
 			if got, want := bulging.IntersectsCell(rootCell), capFace != antiFace; got != want {
 				t.Errorf("Cap(%v).IntersectsCell(%v) = %t; want = %t", bulging, rootCell, got, want)
 			}
-			if got, want := bulging.IntersectsCell(edgeCell), center.Vector.Dot(edgeCell.id.Point().Vector) > 0.1; got != want {
+			if got, want := bulging.IntersectsCell(edgeCell), center.Dot(edgeCell.id.Point().Vector) > 0.1; got != want {
 				t.Errorf("Cap(%v).IntersectsCell(%v) = %t; want = %t", bulging, edgeCell, got, want)
 			}
 			if bulging.IntersectsCell(cornerCell) {

s2/cell_index_test.go

@@ -138,7 +138,7 @@ func verifyCellIndexRangeIterators(t *testing.T, desc string, index *CellIndex)
 			if start != it2.StartID() {
 				t.Errorf("%s: it2.StartID() = %v, want %v", desc, it2.StartID(), start)
 			}
-			if 0 != prevStart {
+			if prevStart != 0 {
 				t.Errorf("%s: prevStart = %v, want %v", desc, prevStart, 0)
 			}
 		}

s2/cellid.go

@@ -361,7 +361,7 @@ func CellIDFromString(s string) CellID {
 	}
 	id := CellIDFromFace(face)
 	for i := 2; i < len(s); i++ {
-		var childPos byte = s[i] - '0'
+		var childPos = s[i] - '0'
 		// Bytes are non-negative.
 		if childPos > 3 {
 			return CellID(0)

s2/cellunion_test.go

@@ -818,7 +818,7 @@ func TestCellUnionFromUnionDiffIntersection(t *testing.T) {
 			u := CellUnionFromIntersectionWithCellID(xcells, yid)
 			for _, xid := range xcells {
 				if xid.Contains(yid) {
-					if !(len(u) == 1 && u[0] == yid) {
+					if !(len(u) == 1 && u[0] == yid) { // nolint staticcheck - DeMorgan's doesn't work here.
 						t.Errorf("CellUnionFromIntersectionWithCellID(%v, %v) = %v with len: %d, want len of 1.", xcells, yid, u, len(u))
 					}
 				} else if yid.Contains(xid) {

s2/crossing_edge_query.go

@@ -277,16 +277,20 @@ func (c *CrossingEdgeQuery) getCellsForEdge(a, b Point) {
 		//  3. edgeRoot does not intersect any index cells. In this case there
 		//     is nothing to do.
 		relation := c.iter.LocateCellID(edgeRoot)
-		if relation == Indexed {
-			// edgeRoot is an index cell or is contained by an index cell (case 1).
+		switch relation {
+		case Indexed:
+			// edgeRoot is an index cell or is contained by an
+			// index cell (case 1).
 			c.cells = append(c.cells, c.iter.IndexCell())
-		} else if relation == Subdivided {
-			// edgeRoot is subdivided into one or more index cells (case 2). We
-			// find the cells intersected by AB using recursive subdivision.
+		case Subdivided:
+			// edgeRoot is subdivided into one or more index cells
+			// (case 2). We find the cells intersected by AB using
+			// recursive subdivision.
 			if !edgeRoot.isFace() {
 				pcell = PaddedCellFromCellID(edgeRoot, 0)
 			}
 			c.computeCellsIntersected(pcell, edgeBound)
+		case Disjoint:
 		}
 	}
 }

s2/edge_clipping.go

@@ -564,7 +564,7 @@ func FaceSegments(a, b Point) []FaceSegment {
 		// Complete the current segment by finding the point where AB
 		// exits the current face.
 		z := faceXYZtoUVW(face, ab)
-		n := pointUVW{z.Vector}
+		n := pointUVW(z)
 
 		exitAxis := n.exitAxis()
 		segment.b = n.exitPoint(exitAxis)
@@ -605,7 +605,7 @@ func moveOriginToValidFace(face int, a, ab Point, aUV r2.Point) (int, r2.Point)
 
 	// Otherwise check whether the normal AB even intersects this face.
 	z := faceXYZtoUVW(face, ab)
-	n := pointUVW{z.Vector}
+	n := pointUVW(z)
 	if n.intersectsFace() {
 		// Check whether the point where the line AB exits this face is on the
 		// wrong side of A (by more than the acceptable error tolerance).

s2/edge_crosser.go

@@ -154,6 +154,8 @@ func (e *EdgeCrosser) EdgeOrVertexChainCrossing(d Point) bool {
 		return false
 	case Cross:
 		return true
+	case MaybeCross:
+		// fall through
 	}
 	return VertexCrossing(e.a, e.b, c, d)
 }

s2/edge_crossings.go

@@ -152,9 +152,10 @@ func EdgeOrVertexCrossing(a, b, c, d Point) bool {
 		return false
 	case Cross:
 		return true
-	default:
-		return VertexCrossing(a, b, c, d)
+	case MaybeCross:
+		// Fall through to the final return.
 	}
+	return VertexCrossing(a, b, c, d)
 }
 
 // Intersection returns the intersection point of two edges AB and CD that cross

s2/edge_distances.go

@@ -96,7 +96,7 @@ func UpdateMinInteriorDistance(x, a, b Point, minDist s1.ChordAngle) (s1.ChordAn
 func Project(x, a, b Point) Point {
 	aXb := a.PointCross(b)
 	// Find the closest point to X along the great circle through AB.
-	p := x.Sub(aXb.Mul(x.Dot(aXb.Vector) / aXb.Vector.Norm2()))
+	p := x.Sub(aXb.Mul(x.Dot(aXb.Vector) / aXb.Norm2()))
 
 	// If this point is on the edge AB, then it's the closest point.
 	if Sign(aXb, a, Point{p}) && Sign(Point{p}, b, aXb) {
@@ -146,7 +146,7 @@ func InterpolateAtDistance(ax s1.Angle, a, b Point) Point {
 	// result is always perpendicular to A, even if A=B or A=-B, but it is not
 	// necessarily unit length. (We effectively normalize it below.)
 	normal := a.PointCross(b)
-	tangent := normal.Vector.Cross(a.Vector)
+	tangent := normal.Cross(a.Vector)
 
 	// Now compute the appropriate linear combination of A and "tangent". With
 	// infinite precision the result would always be unit length, but we

s2/edge_distances_test.go

@@ -427,7 +427,8 @@ func TestEdgeDistancesInterpolate(t *testing.T) {
 					test.a, test.b, r, got, test.want)
 			}
 		}
-		if r.Radians() >= 0 && r.Radians() < 0.99*math.Pi {
+		if r.Radians() >= 0 && r.Radians() < 0.99*math.Pi { // nolint staticcheck
+			// TODO(rsned): Remove nolint when this test case is added.
 			// We don't have the parallel ChordAngle variants of
 			// PointOnLine/Ray/Left/Right
 			// so the second tests are not added here.
@@ -478,7 +479,7 @@ func TestEdgeDistancesRepeatedInterpolation(t *testing.T) {
 		for j := 0; j < 1000; j++ {
 			a = Interpolate(0.01, a, b)
 		}
-		if !a.Vector.IsUnit() {
+		if !a.IsUnit() {
 			t.Errorf("repeated Interpolate(%v, %v, %v) calls did not stay unit length for", 0.01, a, b)
 		}
 	}
@@ -725,7 +726,7 @@ func TestEdgeDistancesEdgePairMinDistance(t *testing.T) {
 		actualA, actualB := EdgePairClosestPoints(test.a0, test.a1, test.b0, test.b1)
 		if test.wantA == zero {
 			// either end point works.
-			if !(actualA == test.a0 || actualA == test.a1) {
+			if actualA != test.a0 && actualA != test.a1 {
 				t.Errorf("EdgePairClosestPoints(%v, %v, %v, %v) = %v, want %v or %v", test.a0, test.a1, test.b0, test.b1, actualA, test.a0, test.a1)
 			}
 		} else {
@@ -736,7 +737,7 @@ func TestEdgeDistancesEdgePairMinDistance(t *testing.T) {
 
 		if test.wantB == zero {
 			// either end point works.
-			if !(actualB == test.b0 || actualB == test.b1) {
+			if actualB != test.b0 && actualB != test.b1 {
 				t.Errorf("EdgePairClosestPoints(%v, %v, %v, %v) = %v, want %v or %v", test.a0, test.a1, test.b0, test.b1, actualB, test.b0, test.b1)
 			}
 		} else {

s2/edge_query_test.go

@@ -242,18 +242,14 @@ func testEdgeQueryWithGenerator(t *testing.T,
 	var indexCaps []Cap
 	var indexes []*ShapeIndex
 	for i := 0; i < numIndexes; i++ {
-		// TODO(rsned): Replace with:
-	        // r := rand.New(rand.NewSource(i))
-		rand.Seed(int64(i))
-		indexCaps = append(indexCaps, CapFromCenterAngle(randomPoint(), testCapRadius))
+	        r := rand.New(rand.NewSource(i))
+		indexCaps = append(indexCaps, CapFromCenterAngle(randomPoint(r), testCapRadius))
 		indexes = append(indexes, NewShapeIndex())
 		gen(indexCaps[i], numEdges, indexes[i])
 	}
 
 	for i := 0; i < numQueries; i++ {
-		// TODO(rsned): Replace with:
-	        // r := rand.New(rand.NewSource(i))
-		rand.Seed(int64(i))
+	        r := rand.New(rand.NewSource(i))
 		iIndex := randomUniformInt(numIndexes)
 		indexCap := indexCaps[iIndex]
 
@@ -273,23 +269,23 @@ func testEdgeQueryWithGenerator(t *testing.T,
 		// Occasionally we don't set any limit on the number of result edges.
 		// (This may return all edges if we also don't set a distance limit.)
 		if oneIn(5) {
-			opts.MaxResults(1 + randomUniformInt(10))
+			opts.MaxResults(1 + randomUniformInt(10, r))
 		}
 
 		// We set a distance limit 1/3 of the time.
 		if oneIn(3) {
-			opts.DistanceLimit(s1.ChordAngleFromAngle(s1.Angle(randomFloat64()) * queryRadius))
+			opts.DistanceLimit(s1.ChordAngleFromAngle(s1.Angle(randomFloat64(r)) * queryRadius))
 		}
 		if oneIn(2) {
 			// Choose a maximum error whose logarithm is uniformly distributed over
 			// a reasonable range, except that it is sometimes zero.
-			opts.MaxError(s1.ChordAngleFromAngle(s1.Angle(math.Pow(1e-4, randomFloat64()) * queryRadius.Radians())))
+			opts.MaxError(s1.ChordAngleFromAngle(s1.Angle(math.Pow(1e-4, randomFloat64(r)) * queryRadius.Radians())))
 		}
 		opts.IncludeInteriors(oneIn(2))
 
 		query := newQueryFunc(indexes[iIndex], opts)
 
-		switch randomUniformInt(4) {
+		switch randomUniformInt(4, r) {
 		case 0:
 			// Find the edges furthest from a given point.
 			point := samplePointFromCap(queryCap)
@@ -299,22 +295,22 @@ func testEdgeQueryWithGenerator(t *testing.T,
 			// Find the edges furthest from a given edge.
 			a := samplePointFromCap(queryCap)
 			b := samplePointFromCap(
-				CapFromCenterAngle(a, s1.Angle(math.Pow(1e-4, randomFloat64()))*queryRadius))
+				CapFromCenterAngle(a, s1.Angle(math.Pow(1e-4, randomFloat64(r)))*queryRadius))
 			target := NewMaxDistanceToEdgeTarget(Edge{a, b})
 			testFindEdges(target, query)
 
 		case 2:
 			// Find the edges furthest from a given cell.
 			minLevel := MaxDiagMetric.MinLevel(queryRadius.Radians())
-			level := minLevel + randomUniformInt(MaxLevel-minLevel+1)
+			level := minLevel + randomUniformInt(MaxLevel-minLevel+1, r)
 			a := samplePointFromCap(queryCap)
 			cell := CellFromCellID(cellIDFromPoint(a).Parent(level))
 			target := NewMaxDistanceToCellTarget(cell)
 			testFindEdges(target, query)
 
 		case 3:
 			// Use another one of the pre-built indexes as the target.
-			jIndex := randomUniformInt(numIndexes)
+			jIndex := randomUniformInt(numIndexes, r)
 			target := NewMaxDistanceToShapeIndexTarget(indexes[jIndex])
 			target.setIncludeInteriors(oneIn(2))
 			testFindEdges(target, query)
@@ -438,9 +434,9 @@ func generateEdgeQueryWithTargets(opts *edgeQueryBenchmarkOptions, query *EdgeQu
 
 	// Set a specific seed to allow repeatability
 	// Replace with r := rand.New(rand.NewSource(opts.randomSeed)) and pass through.
-	rand.Seed(opts.randomSeed)
+	r := rand.New(rand.NewSource(opts.randomSeed))
 	opts.randomSeed++
-	indexCap := CapFromCenterAngle(randomPoint(), opts.radiusKm)
+	indexCap := CapFromCenterAngle(randomPoint(r), opts.radiusKm)
 
 	query.Reset()
 	queryIndex.Reset()

s2/encode_test.go

@@ -27,11 +27,11 @@ import (
 )
 
 type encodableRegion interface {
-	Encode(io.Writer) error
+	Encode(w io.Writer) error
 }
 
 type decodableRegion interface {
-	Decode(io.Reader) error
+	Decode(r io.Reader) error
 }
 
 const (

s2/lax_polygon.go

@@ -92,14 +92,15 @@ func LaxPolygonFromPolygon(p *Polygon) *LaxPolygon {
 func LaxPolygonFromPoints(loops [][]Point) *LaxPolygon {
 	p := &LaxPolygon{}
 	p.numLoops = len(loops)
-	if p.numLoops == 0 {
+	switch p.numLoops {
+	case 0:
 		p.numVerts = 0
 		p.vertices = nil
-	} else if p.numLoops == 1 {
+	case 1:
 		p.numVerts = len(loops[0])
 		p.vertices = make([]Point, p.numVerts)
 		copy(p.vertices, loops[0])
-	} else {
+	default:
 		p.cumulativeVertices = make([]int, p.numLoops+1)
 		numVertices := 0
 		for i, loop := range loops {

s2/loop_test.go

@@ -1350,7 +1350,7 @@ func TestLoopRelations(t *testing.T) {
 			a1 := cloneLoop(test.a)
 			a1.Invert()
 			testLoopNestedPair(t, a1, test.b)
-		} else if !(test.contains || test.contained || test.covers) {
+		} else if !test.contains && !test.contained && !test.covers {
 			// Given loops A and B such that both A and its complement
 			// intersect both B and its complement, test various
 			// identities involving these four loops.

s2/max_distance_targets_test.go

@@ -436,7 +436,7 @@ func TestDistanceTargetMaxShapeIndexTargetCapBound(t *testing.T) {
 		pTest := randomPoint()
 		// Check points outside of cap to be away from maxDistance's zero().
 		if !c.ContainsPoint(pTest) {
-			var curDist distance = inf
+			var curDist = inf
 			var ok bool
 			if curDist, ok = target.updateDistanceToPoint(pTest, curDist); !ok {
 				t.Errorf("updateDistanceToPoint failed, but should have succeeded")

s2/point.go

@@ -123,7 +123,7 @@ func OrderedCCW(a, b, c, o Point) bool {
 
 // Distance returns the angle between two points.
 func (p Point) Distance(b Point) s1.Angle {
-	return p.Vector.Angle(b.Vector)
+	return p.Angle(b.Vector)
 }
 
 // ApproxEqual reports whether the two points are similar enough to be equal.
@@ -133,7 +133,7 @@ func (p Point) ApproxEqual(other Point) bool {
 
 // approxEqual reports whether the two points are within the given epsilon.
 func (p Point) approxEqual(other Point, eps s1.Angle) bool {
-	return p.Vector.Angle(other.Vector) <= eps
+	return p.Angle(other.Vector) <= eps
 }
 
 // ChordAngleBetweenPoints constructs a ChordAngle corresponding to the distance
@@ -254,7 +254,7 @@ func Ortho(a Point) Point {
 		temp.Z = 1
 	case r3.YAxis:
 		temp.X = 1
-	default:
+	case r3.ZAxis:
 		temp.Y = 1
 	}
 	return Point{a.Cross(temp).Normalize()}

s2/polygon.go

@@ -447,7 +447,7 @@ func (p *Polygon) Validate() error {
 	for i, l := range p.loops {
 		// Check for loop errors that don't require building a ShapeIndex.
 		if err := l.findValidationErrorNoIndex(); err != nil {
-			return fmt.Errorf("loop %d: %v", i, err)
+			return fmt.Errorf("loop %d: %w", i, err)
 		}
 		// Check that no loop is empty, and that the full loop only appears in the
 		// full polygon.