First commit

1 files changed, 235 insertions, 0 deletions

diff --git a/pkg/gitdiff/apply_test.go b/pkg/gitdiff/apply_test.go
new file mode 100644
index 0000000..05915ba
--- /dev/null
+++ b/pkg/gitdiff/apply_test.go
@@ -0,0 +1,235 @@
+package gitdiff
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"io/ioutil"
+	"path/filepath"
+	"testing"
+)
+
+func TestApplyTextFragment(t *testing.T) {
+	tests := map[string]applyTest{
+		"createFile": {Files: getApplyFiles("text_fragment_new")},
+		"deleteFile": {Files: getApplyFiles("text_fragment_delete_all")},
+
+		"addStart":    {Files: getApplyFiles("text_fragment_add_start")},
+		"addMiddle":   {Files: getApplyFiles("text_fragment_add_middle")},
+		"addEnd":      {Files: getApplyFiles("text_fragment_add_end")},
+		"addEndNoEOL": {Files: getApplyFiles("text_fragment_add_end_noeol")},
+
+		"changeStart":       {Files: getApplyFiles("text_fragment_change_start")},
+		"changeMiddle":      {Files: getApplyFiles("text_fragment_change_middle")},
+		"changeEnd":         {Files: getApplyFiles("text_fragment_change_end")},
+		"changeEndEOL":      {Files: getApplyFiles("text_fragment_change_end_eol")},
+		"changeExact":       {Files: getApplyFiles("text_fragment_change_exact")},
+		"changeSingleNoEOL": {Files: getApplyFiles("text_fragment_change_single_noeol")},
+
+		"errorShortSrcBefore": {
+			Files: applyFiles{
+				Src:   "text_fragment_error.src",
+				Patch: "text_fragment_error_short_src_before.patch",
+			},
+			Err: &Conflict{},
+		},
+		"errorShortSrc": {
+			Files: applyFiles{
+				Src:   "text_fragment_error.src",
+				Patch: "text_fragment_error_short_src.patch",
+			},
+			Err: &Conflict{},
+		},
+		"errorContextConflict": {
+			Files: applyFiles{
+				Src:   "text_fragment_error.src",
+				Patch: "text_fragment_error_context_conflict.patch",
+			},
+			Err: &Conflict{},
+		},
+		"errorDeleteConflict": {
+			Files: applyFiles{
+				Src:   "text_fragment_error.src",
+				Patch: "text_fragment_error_delete_conflict.patch",
+			},
+			Err: &Conflict{},
+		},
+		"errorNewFile": {
+			Files: applyFiles{
+				Src:   "text_fragment_error.src",
+				Patch: "text_fragment_error_new_file.patch",
+			},
+			Err: &Conflict{},
+		},
+	}
+
+	for name, test := range tests {
+		t.Run(name, func(t *testing.T) {
+			test.run(t, func(dst io.Writer, src io.ReaderAt, file *File) error {
+				if len(file.TextFragments) != 1 {
+					t.Fatalf("patch should contain exactly one fragment, but it has %d", len(file.TextFragments))
+				}
+				applier := NewTextApplier(dst, src)
+				return applier.ApplyFragment(file.TextFragments[0])
+			})
+		})
+	}
+}
+
+func TestApplyBinaryFragment(t *testing.T) {
+	tests := map[string]applyTest{
+		"literalCreate":    {Files: getApplyFiles("bin_fragment_literal_create")},
+		"literalModify":    {Files: getApplyFiles("bin_fragment_literal_modify")},
+		"deltaModify":      {Files: getApplyFiles("bin_fragment_delta_modify")},
+		"deltaModifyLarge": {Files: getApplyFiles("bin_fragment_delta_modify_large")},
+
+		"errorIncompleteAdd": {
+			Files: applyFiles{
+				Src:   "bin_fragment_delta_error.src",
+				Patch: "bin_fragment_delta_error_incomplete_add.patch",
+			},
+			Err: "incomplete add",
+		},
+		"errorIncompleteCopy": {
+			Files: applyFiles{
+				Src:   "bin_fragment_delta_error.src",
+				Patch: "bin_fragment_delta_error_incomplete_copy.patch",
+			},
+			Err: "incomplete copy",
+		},
+		"errorSrcSize": {
+			Files: applyFiles{
+				Src:   "bin_fragment_delta_error.src",
+				Patch: "bin_fragment_delta_error_src_size.patch",
+			},
+			Err: &Conflict{},
+		},
+		"errorDstSize": {
+			Files: applyFiles{
+				Src:   "bin_fragment_delta_error.src",
+				Patch: "bin_fragment_delta_error_dst_size.patch",
+			},
+			Err: "insufficient or extra data",
+		},
+	}
+
+	for name, test := range tests {
+		t.Run(name, func(t *testing.T) {
+			test.run(t, func(dst io.Writer, src io.ReaderAt, file *File) error {
+				applier := NewBinaryApplier(dst, src)
+				return applier.ApplyFragment(file.BinaryFragment)
+			})
+		})
+	}
+}
+
+func TestApplyFile(t *testing.T) {
+	tests := map[string]applyTest{
+		"textModify": {
+			Files: applyFiles{
+				Src:   "file_text.src",
+				Patch: "file_text_modify.patch",
+				Out:   "file_text_modify.out",
+			},
+		},
+		"textDelete": {
+			Files: applyFiles{
+				Src:   "file_text.src",
+				Patch: "file_text_delete.patch",
+				Out:   "file_text_delete.out",
+			},
+		},
+		"textErrorPartialDelete": {
+			Files: applyFiles{
+				Src:   "file_text.src",
+				Patch: "file_text_error_partial_delete.patch",
+			},
+			Err: &Conflict{},
+		},
+		"binaryModify": {
+			Files: getApplyFiles("file_bin_modify"),
+		},
+		"modeChange": {
+			Files: getApplyFiles("file_mode_change"),
+		},
+	}
+
+	for name, test := range tests {
+		t.Run(name, func(t *testing.T) {
+			test.run(t, func(dst io.Writer, src io.ReaderAt, file *File) error {
+				return Apply(dst, src, file)
+			})
+		})
+	}
+}
+
+type applyTest struct {
+	Files applyFiles
+	Err   interface{}
+}
+
+func (at applyTest) run(t *testing.T, apply func(io.Writer, io.ReaderAt, *File) error) {
+	src, patch, out := at.Files.Load(t)
+
+	files, _, err := Parse(bytes.NewReader(patch))
+	if err != nil {
+		t.Fatalf("failed to parse patch file: %v", err)
+	}
+	if len(files) != 1 {
+		t.Fatalf("patch should contain exactly one file, but it has %d", len(files))
+	}
+
+	var dst bytes.Buffer
+	err = apply(&dst, bytes.NewReader(src), files[0])
+	if at.Err != nil {
+		assertError(t, at.Err, err, "applying fragment")
+		return
+	}
+	if err != nil {
+		var aerr *ApplyError
+		if errors.As(err, &aerr) {
+			t.Fatalf("unexpected error applying: at %d: fragment %d at %d: %v", aerr.Line, aerr.Fragment, aerr.FragmentLine, err)
+		} else {
+			t.Fatalf("unexpected error applying: %v", err)
+		}
+	}
+
+	if !bytes.Equal(out, dst.Bytes()) {
+		t.Errorf("incorrect result after apply\nexpected:\n%q\nactual:\n%q", out, dst.Bytes())
+	}
+}
+
+type applyFiles struct {
+	Src   string
+	Patch string
+	Out   string
+}
+
+func getApplyFiles(name string) applyFiles {
+	return applyFiles{
+		Src:   name + ".src",
+		Patch: name + ".patch",
+		Out:   name + ".out",
+	}
+}
+
+func (f applyFiles) Load(t *testing.T) (src []byte, patch []byte, out []byte) {
+	load := func(name, kind string) []byte {
+		d, err := ioutil.ReadFile(filepath.Join("testdata", "apply", name))
+		if err != nil {
+			t.Fatalf("failed to read %s file: %v", kind, err)
+		}
+		return d
+	}
+
+	if f.Src != "" {
+		src = load(f.Src, "source")
+	}
+	if f.Patch != "" {
+		patch = load(f.Patch, "patch")
+	}
+	if f.Out != "" {
+		out = load(f.Out, "output")
+	}
+	return
+}