package difflib import ( "bytes" "fmt" "math" "reflect" "strings" "testing" ) func assertAlmostEqual(t *testing.T, a, b float64, places int) { if math.Abs(a-b) > math.Pow10(-places) { t.Errorf("%.7f != %.7f", a, b) } } func assertEqual(t *testing.T, a, b interface{}) { if !reflect.DeepEqual(a, b) { t.Errorf("%v != %v", a, b) } } func splitChars(s string) []string { chars := make([]string, 0, len(s)) // Assume ASCII inputs for i := 0; i != len(s); i++ { chars = append(chars, string(s[i])) } return chars } func TestSequenceMatcherRatio(t *testing.T) { s := NewMatcher(splitChars("abcd"), splitChars("bcde")) assertEqual(t, s.Ratio(), 0.75) assertEqual(t, s.QuickRatio(), 0.75) assertEqual(t, s.RealQuickRatio(), 1.0) } func TestGetOptCodes(t *testing.T) { a := "qabxcd" b := "abycdf" s := NewMatcher(splitChars(a), splitChars(b)) w := &bytes.Buffer{} for _, op := range s.GetOpCodes() { fmt.Fprintf(w, "%s a[%d:%d], (%s) b[%d:%d] (%s)\n", string(op.Tag), op.I1, op.I2, a[op.I1:op.I2], op.J1, op.J2, b[op.J1:op.J2]) } result := string(w.Bytes()) expected := `d a[0:1], (q) b[0:0] () e a[1:3], (ab) b[0:2] (ab) r a[3:4], (x) b[2:3] (y) e a[4:6], (cd) b[3:5] (cd) i a[6:6], () b[5:6] (f) ` if expected != result { t.Errorf("unexpected op codes: \n%s", result) } } func TestGroupedOpCodes(t *testing.T) { a := []string{} for i := 0; i != 39; i++ { a = append(a, fmt.Sprintf("%02d", i)) } b := []string{} b = append(b, a[:8]...) b = append(b, " i") b = append(b, a[8:19]...) b = append(b, " x") b = append(b, a[20:22]...) b = append(b, a[27:34]...) b = append(b, " y") b = append(b, a[35:]...) s := NewMatcher(a, b) w := &bytes.Buffer{} for _, g := range s.GetGroupedOpCodes(-1) { fmt.Fprintf(w, "group\n") for _, op := range g { fmt.Fprintf(w, " %s, %d, %d, %d, %d\n", string(op.Tag), op.I1, op.I2, op.J1, op.J2) } } result := string(w.Bytes()) expected := `group e, 5, 8, 5, 8 i, 8, 8, 8, 9 e, 8, 11, 9, 12 group e, 16, 19, 17, 20 r, 19, 20, 20, 21 e, 20, 22, 21, 23 d, 22, 27, 23, 23 e, 27, 30, 23, 26 group e, 31, 34, 27, 30 r, 34, 35, 30, 31 e, 35, 38, 31, 34 ` if expected != result { t.Errorf("unexpected op codes: \n%s", result) } } func ExampleGetUnifiedDiffCode() { a := `one two three four fmt.Printf("%s,%T",a,b)` b := `zero one three four` diff := UnifiedDiff{ A: SplitLines(a), B: SplitLines(b), FromFile: "Original", FromDate: "2005-01-26 23:30:50", ToFile: "Current", ToDate: "2010-04-02 10:20:52", Context: 3, } result, _ := GetUnifiedDiffString(diff) fmt.Println(strings.Replace(result, "\t", " ", -1)) // Output: // --- Original 2005-01-26 23:30:50 // +++ Current 2010-04-02 10:20:52 // @@ -1,5 +1,4 @@ // +zero // one // -two // three // four // -fmt.Printf("%s,%T",a,b) } func ExampleGetContextDiffCode() { a := `one two three four fmt.Printf("%s,%T",a,b)` b := `zero one tree four` diff := ContextDiff{ A: SplitLines(a), B: SplitLines(b), FromFile: "Original", ToFile: "Current", Context: 3, Eol: "\n", } result, _ := GetContextDiffString(diff) fmt.Print(strings.Replace(result, "\t", " ", -1)) // Output: // *** Original // --- Current // *************** // *** 1,5 **** // one // ! two // ! three // four // - fmt.Printf("%s,%T",a,b) // --- 1,4 ---- // + zero // one // ! tree // four } func ExampleGetContextDiffString() { a := `one two three four` b := `zero one tree four` diff := ContextDiff{ A: SplitLines(a), B: SplitLines(b), FromFile: "Original", ToFile: "Current", Context: 3, Eol: "\n", } result, _ := GetContextDiffString(diff) fmt.Printf(strings.Replace(result, "\t", " ", -1)) // Output: // *** Original // --- Current // *************** // *** 1,4 **** // one // ! two // ! three // four // --- 1,4 ---- // + zero // one // ! tree // four } func rep(s string, count int) string { return strings.Repeat(s, count) } func TestWithAsciiOneInsert(t *testing.T) { sm := NewMatcher(splitChars(rep("b", 100)), splitChars("a"+rep("b", 100))) assertAlmostEqual(t, sm.Ratio(), 0.995, 3) assertEqual(t, sm.GetOpCodes(), []OpCode{{'i', 0, 0, 0, 1}, {'e', 0, 100, 1, 101}}) assertEqual(t, len(sm.bPopular), 0) sm = NewMatcher(splitChars(rep("b", 100)), splitChars(rep("b", 50)+"a"+rep("b", 50))) assertAlmostEqual(t, sm.Ratio(), 0.995, 3) assertEqual(t, sm.GetOpCodes(), []OpCode{{'e', 0, 50, 0, 50}, {'i', 50, 50, 50, 51}, {'e', 50, 100, 51, 101}}) assertEqual(t, len(sm.bPopular), 0) } func TestWithAsciiOnDelete(t *testing.T) { sm := NewMatcher(splitChars(rep("a", 40)+"c"+rep("b", 40)), splitChars(rep("a", 40)+rep("b", 40))) assertAlmostEqual(t, sm.Ratio(), 0.994, 3) assertEqual(t, sm.GetOpCodes(), []OpCode{{'e', 0, 40, 0, 40}, {'d', 40, 41, 40, 40}, {'e', 41, 81, 40, 80}}) } func TestWithAsciiBJunk(t *testing.T) { isJunk := func(s string) bool { return s == " " } sm := NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)), splitChars(rep("a", 44)+rep("b", 40)), true, isJunk) assertEqual(t, sm.bJunk, map[string]struct{}{}) sm = NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)), splitChars(rep("a", 44)+rep("b", 40)+rep(" ", 20)), false, isJunk) assertEqual(t, sm.bJunk, map[string]struct{}{" ": struct{}{}}) isJunk = func(s string) bool { return s == " " || s == "b" } sm = NewMatcherWithJunk(splitChars(rep("a", 40)+rep("b", 40)), splitChars(rep("a", 44)+rep("b", 40)+rep(" ", 20)), false, isJunk) assertEqual(t, sm.bJunk, map[string]struct{}{" ": struct{}{}, "b": struct{}{}}) } func TestSFBugsRatioForNullSeqn(t *testing.T) { sm := NewMatcher(nil, nil) assertEqual(t, sm.Ratio(), 1.0) assertEqual(t, sm.QuickRatio(), 1.0) assertEqual(t, sm.RealQuickRatio(), 1.0) } func TestSFBugsComparingEmptyLists(t *testing.T) { groups := NewMatcher(nil, nil).GetGroupedOpCodes(-1) assertEqual(t, len(groups), 0) diff := UnifiedDiff{ FromFile: "Original", ToFile: "Current", Context: 3, } result, err := GetUnifiedDiffString(diff) assertEqual(t, err, nil) assertEqual(t, result, "") } func TestOutputFormatRangeFormatUnified(t *testing.T) { // Per the diff spec at http://www.unix.org/single_unix_specification/ // // Each field shall be of the form: // %1d", if the range contains exactly one line, // and: // "%1d,%1d", , otherwise. // If a range is empty, its beginning line number shall be the number of // the line just before the range, or 0 if the empty range starts the file. fm := formatRangeUnified assertEqual(t, fm(3, 3), "3,0") assertEqual(t, fm(3, 4), "4") assertEqual(t, fm(3, 5), "4,2") assertEqual(t, fm(3, 6), "4,3") assertEqual(t, fm(0, 0), "0,0") } func TestOutputFormatRangeFormatContext(t *testing.T) { // Per the diff spec at http://www.unix.org/single_unix_specification/ // // The range of lines in file1 shall be written in the following format // if the range contains two or more lines: // "*** %d,%d ****\n", , // and the following format otherwise: // "*** %d ****\n", // The ending line number of an empty range shall be the number of the preceding line, // or 0 if the range is at the start of the file. // // Next, the range of lines in file2 shall be written in the following format // if the range contains two or more lines: // "--- %d,%d ----\n", , // and the following format otherwise: // "--- %d ----\n", fm := formatRangeContext assertEqual(t, fm(3, 3), "3") assertEqual(t, fm(3, 4), "4") assertEqual(t, fm(3, 5), "4,5") assertEqual(t, fm(3, 6), "4,6") assertEqual(t, fm(0, 0), "0") } func TestOutputFormatTabDelimiter(t *testing.T) { diff := UnifiedDiff{ A: splitChars("one"), B: splitChars("two"), FromFile: "Original", FromDate: "2005-01-26 23:30:50", ToFile: "Current", ToDate: "2010-04-12 10:20:52", Eol: "\n", } ud, err := GetUnifiedDiffString(diff) assertEqual(t, err, nil) assertEqual(t, SplitLines(ud)[:2], []string{ "--- Original\t2005-01-26 23:30:50\n", "+++ Current\t2010-04-12 10:20:52\n", }) cd, err := GetContextDiffString(ContextDiff(diff)) assertEqual(t, err, nil) assertEqual(t, SplitLines(cd)[:2], []string{ "*** Original\t2005-01-26 23:30:50\n", "--- Current\t2010-04-12 10:20:52\n", }) } func TestOutputFormatNoTrailingTabOnEmptyFiledate(t *testing.T) { diff := UnifiedDiff{ A: splitChars("one"), B: splitChars("two"), FromFile: "Original", ToFile: "Current", Eol: "\n", } ud, err := GetUnifiedDiffString(diff) assertEqual(t, err, nil) assertEqual(t, SplitLines(ud)[:2], []string{"--- Original\n", "+++ Current\n"}) cd, err := GetContextDiffString(ContextDiff(diff)) assertEqual(t, err, nil) assertEqual(t, SplitLines(cd)[:2], []string{"*** Original\n", "--- Current\n"}) } func TestOmitFilenames(t *testing.T) { diff := UnifiedDiff{ A: SplitLines("o\nn\ne\n"), B: SplitLines("t\nw\no\n"), Eol: "\n", } ud, err := GetUnifiedDiffString(diff) assertEqual(t, err, nil) assertEqual(t, SplitLines(ud), []string{ "@@ -0,0 +1,2 @@\n", "+t\n", "+w\n", "@@ -2,2 +3,0 @@\n", "-n\n", "-e\n", "\n", }) cd, err := GetContextDiffString(ContextDiff(diff)) assertEqual(t, err, nil) assertEqual(t, SplitLines(cd), []string{ "***************\n", "*** 0 ****\n", "--- 1,2 ----\n", "+ t\n", "+ w\n", "***************\n", "*** 2,3 ****\n", "- n\n", "- e\n", "--- 3 ----\n", "\n", }) } func TestSplitLines(t *testing.T) { allTests := []struct { input string want []string }{ {"foo", []string{"foo\n"}}, {"foo\nbar", []string{"foo\n", "bar\n"}}, {"foo\nbar\n", []string{"foo\n", "bar\n", "\n"}}, } for _, test := range allTests { assertEqual(t, SplitLines(test.input), test.want) } } func benchmarkSplitLines(b *testing.B, count int) { str := strings.Repeat("foo\n", count) b.ResetTimer() n := 0 for i := 0; i < b.N; i++ { n += len(SplitLines(str)) } } func BenchmarkSplitLines100(b *testing.B) { benchmarkSplitLines(b, 100) } func BenchmarkSplitLines10000(b *testing.B) { benchmarkSplitLines(b, 10000) }