ci: replace golangci-lint with staticcheck

.github/workflows/golangci-lint.yml

@@ -1,16 +0,0 @@
-name: golangci-lint
-on:
-  pull_request:
-jobs:
-  golangci:
-    name: lint
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - name: golangci-lint
-        uses: golangci/golangci-lint-action@v2.5.2
-        with:
-          # Required: the version of golangci-lint is required and must be specified without patch version: we always use the latest patch version.
-          version: v1.44.2
-          only-new-issues: true
-          args: --timeout=5m

.github/workflows/staticcheck.yml

@@ -0,0 +1,18 @@
+name: Staticcheck
+on:
+  pull_request:
+    branches: [master]
+
+jobs:
+  ci:
+    name: lint
+    runs-on: ubuntu-latest
+    env:
+        GO111MODULE: on
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        fetch-depth: 1
+    - uses: dominikh/staticcheck-action@v1.2.0
+      with:
+        version: "2022.1"

blas/testblas/benchautogen/autogen_bench_level1double.go

@@ -292,14 +292,14 @@ type errFile struct {
 	err  error
 }
 
-func (f errFile) Write(b []byte) {
+func (f *errFile) Write(b []byte) {
 	if f.err != nil {
 		return
 	}
 	_, f.err = f.file.Write(b)
 }
 
-func (f errFile) WriteString(s string) {
+func (f *errFile) WriteString(s string) {
 	if f.err != nil {
 		return
 	}

graph/formats/rdf/check.go

@@ -1,6 +1,6 @@
 
 //line check.rl:1
-// Go code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
+// Code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
 
 // Copyright ©2020 The Gonum Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style

graph/formats/rdf/check.rl

@@ -1,4 +1,4 @@
-// Go code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
+// Code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
 
 // Copyright ©2020 The Gonum Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style

graph/formats/rdf/extract.go

@@ -1,6 +1,6 @@
 
 //line extract.rl:1
-// Go code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
+// Code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
 
 // Copyright ©2020 The Gonum Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style

graph/formats/rdf/extract.rl

@@ -1,4 +1,4 @@
-// Go code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
+// Code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
 
 // Copyright ©2020 The Gonum Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style

graph/formats/rdf/iso_canonical.go

@@ -282,11 +282,11 @@ func hashBNodes(statements []*Statement, h hash.Hash, zero []byte, hash0 map[str
 				}
 			case isIRI(t):
 				h.Reset()
-				h.Write([]byte(t[1 : len(t)-1])) //nolint:errcheck
+				h.Write([]byte(t[1 : len(t)-1]))
 				curr.set(t, h.Sum(nil))
 			default:
 				h.Reset()
-				h.Write([]byte(t)) //nolint:errcheck
+				h.Write([]byte(t))
 				curr.set(t, h.Sum(nil))
 			}
 		}
@@ -515,7 +515,7 @@ func (b lexical) Swap(i, j int)      { b[i], b[j] = b[j], b[i] }
 func hashTuple(h hash.Hash, t ...[]byte) []byte {
 	h.Reset()
 	for _, b := range t {
-		h.Write(b) //nolint:errcheck
+		h.Write(b)
 	}
 	return h.Sum(nil)
 }

graph/formats/rdf/iso_canonical_test.go

@@ -312,7 +312,7 @@ func hashBlanks(s []*Statement, h hash.Hash) ([]*Statement, map[string]string) {
 				continue
 			}
 			h.Reset()
-			h.Write([]byte(t)) //nolint:errcheck
+			h.Write([]byte(t))
 			terms[t] = fmt.Sprintf("_:%0*x", 2*h.Size(), h.Sum(nil))
 		}
 	}
@@ -334,7 +334,7 @@ func mangleFirstIL(s []*Statement, h hash.Hash) ([]*Statement, map[string]string
 				continue
 			}
 			h.Reset()
-			h.Write([]byte(t)) //nolint:errcheck
+			h.Write([]byte(t))
 			terms[t] = fmt.Sprintf(`"%0*x"`, 2*h.Size(), h.Sum(nil))
 			return relabelStatements(s, terms), terms
 		}

graph/formats/rdf/parse.go

@@ -1,6 +1,6 @@
 
 //line parse.rl:1
-// Go code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
+// Code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
 
 // Copyright ©2020 The Gonum Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style

graph/formats/rdf/parse.rl

@@ -1,4 +1,4 @@
-// Go code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
+// Code generated by go generate gonum.org/v1/gonum/graph/formats/rdf; DO NOT EDIT.
 
 // Copyright ©2020 The Gonum Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style

graph/formats/rdf/urna.go

@@ -368,7 +368,7 @@ func (u *urna) hashNDegreeQuads(b string, names *issuer) ([]byte, *issuer) {
 		// 5.5
 		final = append(final, chosenPath...)
 		u.hash.Reset()
-		u.hash.Write(final) //nolint:errcheck
+		u.hash.Write(final)
 
 		names = chosenIssuer // 5.6
 	}
@@ -468,23 +468,23 @@ func (u *urna) hashRelatedBlank(term string, s *Statement, names *issuer, pos by
 
 	// 2.
 	u.hash.Reset()
-	u.hash.Write([]byte{pos}) //nolint:errcheck
+	u.hash.Write([]byte{pos})
 
 	if pos != 'g' { // 3.
 		if u.label == "" {
 			// URDNA2015: Term.Value retained the angle quotes
 			// so we don't need to add them.
-			u.hash.Write([]byte(s.Predicate.Value)) //nolint:errcheck
+			u.hash.Write([]byte(s.Predicate.Value))
 		} else {
 			// URGNA2012 does not delimit predicate by < and >.
 			// https://json-ld.github.io/rdf-dataset-canonicalization/spec/index.html#urgna2012
 			// with reference to 4.7.
-			u.hash.Write([]byte(unquoteIRI(s.Predicate.Value))) //nolint:errcheck
+			u.hash.Write([]byte(unquoteIRI(s.Predicate.Value)))
 		}
 	}
 
 	// 4. and 5.
-	u.hash.Write([]byte(b)) //nolint:errcheck
+	u.hash.Write([]byte(b))
 	return hex(u.hash.Sum(nil))
 }
 

graph/internal/set/set_test.go

@@ -46,10 +46,6 @@ func TestSameInt64s(t *testing.T) {
 
 func TestAddInt64s(t *testing.T) {
 	s := make(Int64s)
-	if s == nil {
-		t.Fatal("Set cannot be created successfully")
-	}
-
 	if s.Count() != 0 {
 		t.Error("Set somehow contains new elements upon creation")
 	}
@@ -183,10 +179,6 @@ func TestSameInts(t *testing.T) {
 
 func TestAddInts(t *testing.T) {
 	s := make(Ints)
-	if s == nil {
-		t.Fatal("Set cannot be created successfully")
-	}
-
 	if s.Count() != 0 {
 		t.Error("Set somehow contains new elements upon creation")
 	}

graph/iterator/map.go

@@ -31,6 +31,7 @@ type emptyInterface struct {
 // Having a clone here allows us to embed a map iterator
 // inside type mapIter so that mapIters can be re-used
 // without doing any allocations.
+//lint:ignore U1000 This is a verbatim copy of the runtime type.
 type hiter struct {
 	key         unsafe.Pointer
 	elem        unsafe.Pointer

internal/asm/f64/axpy_test.go

@@ -245,7 +245,7 @@ func TestAxpyIncTo(t *testing.T) {
 			if inc.x*inc.y < 0 {
 				want = test.wantRev
 			}
-			var iW, incW int = 0, 1
+			iW, incW := 0, 1
 			if inc.y*inc.dst < 0 {
 				iW, incW = len(want)-1, -1
 			}

internal/asm/f64/stubs_test.go

@@ -453,7 +453,7 @@ func TestDivTo(t *testing.T) {
 }
 
 func TestL1Dist(t *testing.T) {
-	var t_gd, s_gd float64 = -inf, inf
+	t_gd, s_gd := -inf, inf
 	for j, v := range []struct {
 		s, t   []float64
 		expect float64

internal/asm/staticcheck.conf

@@ -0,0 +1 @@
+checks = ["inherit", "-U1000"]

internal/cmplx64/cmath_test.go

@@ -17,6 +17,7 @@ import (
 // The higher-precision values in vc26 were used to derive the
 // input arguments vc (see also comment below). For reference
 // only (do not delete).
+//lint:ignore U1000 See comment above.
 var vc26 = []complex64{
 	(4.97901192488367350108546816 + 7.73887247457810456552351752i),
 	(7.73887247457810456552351752 - 0.27688005719200159404635997i),

lapack/testlapack/dgeev_bench.go

@@ -13,9 +13,8 @@ import (
 	"gonum.org/v1/gonum/lapack"
 )
 
-var resultGeneral blas64.General
-
 func DgeevBenchmark(b *testing.B, impl Dgeever) {
+	var resultGeneral blas64.General
 	rnd := rand.New(rand.NewSource(1))
 	benchmarks := []struct {
 		name string
@@ -59,4 +58,7 @@ func DgeevBenchmark(b *testing.B, impl Dgeever) {
 			resultGeneral = a
 		})
 	}
+	if resultGeneral.Data == nil {
+		b.Error("unexpected nil data")
+	}
 }

lapack/testlapack/dlangb_bench.go

@@ -6,6 +6,7 @@ package testlapack
 
 import (
 	"fmt"
+	"math"
 	"testing"
 
 	"golang.org/x/exp/rand"
@@ -14,6 +15,7 @@ import (
 )
 
 func DlangbBenchmark(b *testing.B, impl Dlangber) {
+	var result float64
 	rnd := rand.New(rand.NewSource(1))
 	for _, bm := range []struct {
 		n, k int
@@ -83,4 +85,7 @@ func DlangbBenchmark(b *testing.B, impl Dlangber) {
 			})
 		}
 	}
+	if math.IsNaN(result) {
+		b.Error("unexpected NaN result")
+	}
 }

lapack/testlapack/dlantb_bench.go

@@ -6,6 +6,7 @@ package testlapack
 
 import (
 	"fmt"
+	"math"
 	"testing"
 
 	"golang.org/x/exp/rand"
@@ -14,9 +15,8 @@ import (
 	"gonum.org/v1/gonum/lapack"
 )
 
-var result float64
-
 func DlantbBenchmark(b *testing.B, impl Dlantber) {
+	var result float64
 	rnd := rand.New(rand.NewSource(1))
 	for _, bm := range []struct {
 		n, k int
@@ -51,4 +51,7 @@ func DlantbBenchmark(b *testing.B, impl Dlantber) {
 			}
 		}
 	}
+	if math.IsNaN(result) {
+		b.Error("unexpected NaN result")
+	}
 }

lapack/testlapack/fortran.go

@@ -11,9 +11,11 @@ import (
 
 // This file implements types for helping to convert to Fortran testing capabilities.
 
+//lint:file-ignore U1000 A number of functions are here that may be used in future.
+
 // fortran64 is a float64 type that prints as a double precision constant in
 // Fortran format.
-type fortran64 float64 //nolint:unused
+type fortran64 float64
 
 func (f fortran64) String() string {
 	// Replace exponent with D
@@ -24,7 +26,6 @@ func (f fortran64) String() string {
 
 // printFortranArray prints a Go slice as an array that can be copied into a
 // fortran script.
-//nolint:deadcode,unused
 func printFortranArray(z []float64, name string) {
 	fmt.Printf("%s(1:%d) = (/%v, &\n", name, len(z), fortran64(z[0]))
 	for i := 1; i < len(z)-1; i++ {

lapack/testlapack/general.go

@@ -917,7 +917,7 @@ func constructQPBidiagonal(vect lapack.ApplyOrtho, m, n, nb int, a []float64, ld
 // printRowise prints the matrix with one row per line. This is useful for debugging.
 // If beyond is true, it prints beyond the final column to lda. If false, only
 // the columns are printed.
-//nolint:deadcode,unused
+//lint:ignore U1000 This is useful for debugging.
 func printRowise(a []float64, m, n, lda int, beyond bool) {
 	for i := 0; i < m; i++ {
 		end := n
@@ -1113,6 +1113,7 @@ func isSchurCanonicalGeneral(t blas64.General) bool {
 
 // schurBlockEigenvalues returns the two eigenvalues of the 2×2 matrix [a b; c d]
 // that must be in Schur canonical form.
+//lint:ignore U1000 This is useful for debugging.
 func schurBlockEigenvalues(a, b, c, d float64) (ev1, ev2 complex128) {
 	if !isSchurCanonical(a, b, c, d) {
 		panic("block not in Schur canonical form")

mat/cholesky_test.go

@@ -460,7 +460,7 @@ func TestCholeskySymRankOne(t *testing.T) {
 				0, 0, 6, 10,
 				0, 0, 0, 20,
 			}),
-			alpha:  -1 / 2,
+			alpha:  -0.5,
 			x:      []float64{0, 0, 0, 1},
 			wantOk: true,
 		},

mat/index_no_bound_checks.go

@@ -319,15 +319,6 @@ func (t *TriBandDense) SetTriBand(i, j int, v float64) {
 	t.mat.Data[i*t.mat.Stride+pj] = v
 }
 
-func (t *TriBandDense) setTriBand(i, j int, v float64) {
-	var kl int
-	if !t.isUpper() {
-		kl = t.mat.K
-	}
-	pj := j + kl - i
-	t.mat.Data[i*t.mat.Stride+pj] = v
-}
-
 // At returns the element at row i, column j.
 func (d *DiagDense) At(i, j int) float64 {
 	if uint(i) >= uint(d.mat.N) {

mat/list_test.go

@@ -2,7 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//nolint:deadcode,unused
+//lint:file-ignore U1000 A number of functions are here that may be used in future.
+
 package mat
 
 import (

mat/shadow.go

@@ -207,6 +207,7 @@ func (s *SymBandDense) checkOverlap(a blas64.General) bool {
 	return checkOverlap(generalFromSymmetricBand(s.RawSymBand()), a)
 }
 
+//lint:ignore U1000 This will be used when we do shadow checks for banded matrices.
 func (s *SymBandDense) checkOverlapMatrix(a Matrix) bool {
 	if s == a {
 		return false

mat/triband.go

@@ -324,6 +324,7 @@ func (t *TriBandDense) reuseAsZeroed(n, k int, kind TriKind) {
 // with the given bandwidth and orientation. If the receiver is not empty,
 // reuseAsZeroed checks that the receiver has the correct size, bandwidth and
 // orientation.
+//lint:ignore U1000 This will be used later.
 func (t *TriBandDense) reuseAsNonZeroed(n, k int, kind TriKind) {
 	// reuseAsNonZeroed must be kept in sync with reuseAsZeroed.
 	if n == 0 {

mathext/internal/amos/staticcheck.conf

@@ -0,0 +1 @@
+checks = []

mathext/internal/cephes/staticcheck.conf

@@ -0,0 +1 @@
+checks = []

staticcheck.conf

@@ -0,0 +1 @@
+checks = ["inherit", "-ST1012"]