simplify test assertions + rename file contents cataloger size limiter var

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

syft/file/contents_cataloger.go

@@ -11,14 +11,14 @@ import (
 )
 
 type ContentsCataloger struct {
-	globs              []string
-	skipFilesAboveSize int64
+	globs                     []string
+	skipFilesAboveSizeInBytes int64
 }
 
 func NewContentsCataloger(globs []string, skipFilesAboveSize int64) (*ContentsCataloger, error) {
 	return &ContentsCataloger{
-		globs:              globs,
-		skipFilesAboveSize: skipFilesAboveSize,
+		globs:                     globs,
+		skipFilesAboveSizeInBytes: skipFilesAboveSize,
 	}, nil
 }
 
@@ -37,7 +37,7 @@ func (i *ContentsCataloger) Catalog(resolver source.FileResolver) (map[source.Lo
 			return nil, err
 		}
 
-		if i.skipFilesAboveSize > 0 && metadata.Size > i.skipFilesAboveSize {
+		if i.skipFilesAboveSizeInBytes > 0 && metadata.Size > i.skipFilesAboveSizeInBytes {
 			continue
 		}
 
@@ -61,7 +61,7 @@ func (i *ContentsCataloger) catalogLocation(resolver source.FileResolver, locati
 
 	buf := &bytes.Buffer{}
 	if _, err = io.Copy(base64.NewEncoder(base64.StdEncoding, buf), contentReader); err != nil {
-		return "", fmt.Errorf("unable to observe contents of %+v: %+v", location.RealPath, err)
+		return "", fmt.Errorf("unable to observe contents of %+v: %w", location.RealPath, err)
 	}
 
 	return buf.String(), nil

syft/file/contents_cataloger_test.go

@@ -11,12 +11,11 @@ func TestContentsCataloger(t *testing.T) {
 	allFiles := []string{"test-fixtures/last/path.txt", "test-fixtures/another-path.txt", "test-fixtures/a-path.txt"}
 
 	tests := []struct {
-		name       string
-		globs      []string
-		maxSize    int64
-		files      []string
-		expected   map[source.Location]string
-		catalogErr bool
+		name     string
+		globs    []string
+		maxSize  int64
+		files    []string
+		expected map[source.Location]string
 	}{
 		{
 			name:  "multi-pattern",
@@ -68,20 +67,11 @@ func TestContentsCataloger(t *testing.T) {
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
 			c, err := NewContentsCataloger(test.globs, test.maxSize)
-			if err != nil {
-				t.Fatalf("could not create cataloger: %+v", err)
-			}
+			assert.NoError(t, err)
 
 			resolver := source.NewMockResolverForPaths(test.files...)
 			actual, err := c.Catalog(resolver)
-			if err != nil && !test.catalogErr {
-				t.Fatalf("could not catalog (but should have been able to): %+v", err)
-			} else if err == nil && test.catalogErr {
-				t.Fatalf("expected catalog error but did not get one")
-			} else if test.catalogErr && err != nil {
-				return
-			}
-
+			assert.NoError(t, err)
 			assert.Equal(t, test.expected, actual, "mismatched contents")
 
 		})

syft/pkg/cataloger/common/generic_cataloger_test.go

@@ -6,6 +6,8 @@ import (
 	"io/ioutil"
 	"testing"
 
+	"github.com/stretchr/testify/assert"
+
 	"github.com/anchore/syft/syft/pkg"
 	"github.com/anchore/syft/syft/source"
 )
@@ -46,13 +48,8 @@ func TestGenericCataloger(t *testing.T) {
 	}
 
 	actualPkgs, err := cataloger.Catalog(resolver)
-	if err != nil {
-		t.Fatalf("cataloger catalog action failed: %+v", err)
-	}
-
-	if len(actualPkgs) != len(expectedPkgs) {
-		t.Fatalf("unexpected packages len: %d != %d", len(expectedPkgs), len(actualPkgs))
-	}
+	assert.NoError(t, err)
+	assert.Len(t, actualPkgs, len(expectedPkgs))
 
 	for _, p := range actualPkgs {
 		ref := p.Locations[0]