simplify tests; enable testifylint, usetesting linters

.golangci.yml

@@ -1,4 +1,7 @@
 linters:
+  enable:
+    - testifylint
+    - usetesting
   disable:
     - errcheck
 

diff_test.go

@@ -13,5 +13,5 @@ func TestPrettyDiff(t *testing.T) {
 		[]byte("line 1\nline 2"),
 		[]byte("line 1\nline 2 modified"),
 	)
-	assert.Nil(t, err)
+	assert.NoError(t, err)
 }

graph_test.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/dave/dst/decorator"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 var (
@@ -41,11 +42,11 @@ digraph {
 
 func TestCreateDot(t *testing.T) {
 	node, err := decorator.Parse(testCode)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	out := &bytes.Buffer{}
 	err = CreateDot(node, out)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	assert.Equal(t, strings.TrimSpace(expDot), out.String())
 }

main_test.go

@@ -9,6 +9,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 var testFiles = map[string]string{
@@ -27,28 +28,22 @@ func main() {
 }
 
 func TestRunDir(t *testing.T) {
-	tmpDir, err := os.MkdirTemp("", "go")
-	if err != nil {
-		t.Fatal("Unexpected error creating temp dir", err)
-	}
-	defer os.RemoveAll(tmpDir)
+	tmpDir := t.TempDir()
 
 	paths = &[]string{tmpDir}
 	writeOutput = boolPtr(false)
 	listFiles = boolPtr(false)
 
 	writeTestFiles(t, testFiles, false, tmpDir)
 
-	err = run()
-	assert.Nil(t, err)
+	err := run()
+	require.NoError(t, err)
 
 	// Without writeOutput set to true, inputs should be unchanged
 	for name, contents := range testFiles {
 		path := filepath.Join(tmpDir, name)
 		bytes, err := os.ReadFile(path)
-		if err != nil {
-			t.Fatal("Unexpected error reading test file", err)
-		}
+		require.NoError(t, err, "Unexpected error reading test file")
 
 		assert.Equal(
 			t,
@@ -59,16 +54,14 @@ func TestRunDir(t *testing.T) {
 
 	writeOutput = boolPtr(true)
 	err = run()
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	// Now, files should be modified in place
 	for name, contents := range testFiles {
 		path := filepath.Join(tmpDir, name)
 
 		bytes, err := os.ReadFile(path)
-		if err != nil {
-			t.Fatal("Unexpected error reading test file", err)
-		}
+		require.NoError(t, err, "Unexpected error reading test file")
 
 		assert.NotEqual(
 			t,
@@ -79,29 +72,23 @@ func TestRunDir(t *testing.T) {
 }
 
 func TestRunFilePaths(t *testing.T) {
-	tmpDir, err := os.MkdirTemp("", "go")
-	if err != nil {
-		t.Fatal("Unexpected error creating temp dir", err)
-	}
-	defer os.RemoveAll(tmpDir)
+	tmpDir := t.TempDir()
 
 	paths = &[]string{}
 	writeOutput = boolPtr(true)
 	listFiles = boolPtr(false)
 
 	writeTestFiles(t, testFiles, true, tmpDir)
 
-	err = run()
-	assert.Nil(t, err)
+	err := run()
+	require.NoError(t, err)
 
 	// Now, files should be modified in place
 	for name, contents := range testFiles {
 		path := filepath.Join(tmpDir, name)
 
 		bytes, err := os.ReadFile(path)
-		if err != nil {
-			t.Fatal("Unexpected error reading test file", err)
-		}
+		require.NoError(t, err, "Unexpected error reading test file")
 
 		assert.NotEqual(
 			t,
@@ -112,11 +99,7 @@ func TestRunFilePaths(t *testing.T) {
 }
 
 func TestRunListFiles(t *testing.T) {
-	tmpDir, err := os.MkdirTemp("", "go")
-	if err != nil {
-		t.Fatal("Unexpected error creating temp dir", err)
-	}
-	defer os.RemoveAll(tmpDir)
+	tmpDir := t.TempDir()
 
 	paths = &[]string{}
 	listFiles = boolPtr(true)
@@ -132,7 +115,7 @@ func TestRunListFiles(t *testing.T) {
 	writeTestFiles(t, updatedTestFiles, true, tmpDir)
 
 	output, err := captureStdout(t, run)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	// Only first two files appear in output list
 	expectedPaths := []string{
@@ -171,9 +154,7 @@ func writeTestFiles(
 		}
 
 		err := os.WriteFile(path, []byte(contents), 0644)
-		if err != nil {
-			t.Fatal("Unexpected error writing test file", err)
-		}
+		require.NoError(t, err, "Unexpected error writing test file")
 	}
 }
 
@@ -184,18 +165,14 @@ func captureStdout(t *testing.T, f func() error) (string, error) {
 	}()
 
 	r, w, err := os.Pipe()
-	if err != nil {
-		t.Fatal("Unexpected error opening pipe", err)
-	}
+	require.NoError(t, err, "Unexpected error opening pipe")
 	os.Stdout = w
 
 	resultErr := f()
 
 	w.Close()
 	outBytes, err := io.ReadAll(r)
-	if err != nil {
-		t.Fatal("Unexpected error reading result", err)
-	}
+	require.NoError(t, err, "Unexpected error reading result")
 	w.Close()
 
 	return string(outBytes), resultErr

shortener_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 const fixturesDir = "_fixtures"
@@ -16,7 +17,7 @@ const fixturesDir = "_fixtures"
 // environment variable set to "true".
 func TestShortener(t *testing.T) {
 	info, err := os.ReadDir(fixturesDir)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	fixturePaths := []string{}
 
@@ -35,11 +36,7 @@ func TestShortener(t *testing.T) {
 		)
 	}
 
-	dotDir, err := os.MkdirTemp("", "dot")
-	if err != nil {
-		t.Fatalf("Error creating output directory for dot files: %+v", err)
-	}
-	defer os.RemoveAll(dotDir)
+	dotDir := t.TempDir()
 
 	shortener := NewShortener(
 		ShortenerConfig{
@@ -57,38 +54,20 @@ func TestShortener(t *testing.T) {
 
 	for _, fixturePath := range fixturePaths {
 		contents, err := os.ReadFile(fixturePath)
-		if err != nil {
-			t.Fatalf(
-				"Unexpected error reading fixture %s: %+v",
-				fixturePath,
-				err,
-			)
-		}
+		require.NoErrorf(t, err, "Unexpected error reading fixture %s", fixturePath)
 
 		shortenedContents, err := shortener.Shorten(contents)
-		assert.Nil(t, err)
+		require.NoError(t, err)
 
 		expectedPath := fixturePath[0:len(fixturePath)-3] + "__exp" + ".go"
 
 		if os.Getenv("REGENERATE_TEST_OUTPUTS") == "true" {
 			err := os.WriteFile(expectedPath, shortenedContents, 0644)
-			if err != nil {
-				t.Fatalf(
-					"Unexpected error writing output file %s: %+v",
-					expectedPath,
-					err,
-				)
-			}
+			require.NoErrorf(t, err, "Unexpected error writing output file %s", expectedPath)
 		}
 
 		expectedContents, err := os.ReadFile(expectedPath)
-		if err != nil {
-			t.Fatalf(
-				"Unexpected error reading expected file %s: %+v",
-				expectedPath,
-				err,
-			)
-		}
+		require.NoErrorf(t, err, "Unexpected error reading expected file %s", expectedPath)
 
 		assert.Equal(t, string(expectedContents), string(shortenedContents))
 	}