fix file digest cataloger when passed coordinates (#2436)

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

syft/file/cataloger/filedigest/cataloger.go

@@ -37,7 +37,11 @@ func (i *Cataloger) Catalog(resolver file.Resolver, coordinates ...file.Coordina
 		locations = intCataloger.AllRegularFiles(resolver)
 	} else {
 		for _, c := range coordinates {
-			locations = append(locations, file.NewLocationFromCoordinates(c))
+			locs, err := resolver.FilesByPath(c.RealPath)
+			if err != nil {
+				return nil, fmt.Errorf("unable to get file locations for path %q: %w", c.RealPath, err)
+			}
+			locations = append(locations, locs...)
 		}
 	}
 

syft/file/cataloger/filedigest/cataloger_test.go

@@ -160,3 +160,47 @@ func TestDigestsCataloger_MixFileTypes(t *testing.T) {
 		})
 	}
 }
+
+func TestFileDigestCataloger_GivenCoordinates(t *testing.T) {
+	testImage := "image-file-type-mix"
+
+	img := imagetest.GetFixtureImage(t, "docker-archive", testImage)
+
+	c := NewCataloger([]crypto.Hash{crypto.SHA256})
+
+	src, err := source.NewFromStereoscopeImageObject(img, testImage, nil)
+	require.NoError(t, err)
+
+	resolver, err := src.FileResolver(source.SquashedScope)
+	require.NoError(t, err)
+
+	tests := []struct {
+		path     string
+		exists   bool
+		expected string
+	}{
+		{
+			path:     "/file-1.txt",
+			exists:   true,
+			expected: "b089629781f05ef805b4511e93717f2ffa4c9d991771d5cbfa4b7242b4ef5fff",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.path, func(t *testing.T) {
+			_, ref, err := img.SquashedTree().File(stereoscopeFile.Path(test.path))
+			require.NoError(t, err)
+
+			l := file.NewLocationFromImage(test.path, *ref.Reference, img)
+
+			// note: an important difference between this test and the previous is that this test is using a list
+			// of specific coordinates to catalog
+			actual, err := c.Catalog(resolver, l.Coordinates)
+			require.NoError(t, err)
+			require.Len(t, actual, 1)
+
+			assert.Equal(t, test.expected, actual[l.Coordinates][0].Value, "mismatched digests")
+		})
+	}
+
+}

syft/file/cataloger/filemetadata/cataloger_test.go

@@ -168,7 +168,6 @@ func TestFileMetadataCataloger_GivenCoordinates(t *testing.T) {
 		path     string
 		exists   bool
 		expected file.Metadata
-		err      bool
 	}{
 		{
 			path:   "/file-1.txt",