github.com/pankona/gometalinter@v2.0.11+incompatible/_linters/src/gopkg.in/yaml.v2/encode.go (about)

     1  package yaml
     2  
     3  import (
     4  	"encoding"
     5  	"fmt"
     6  	"io"
     7  	"reflect"
     8  	"regexp"
     9  	"sort"
    10  	"strconv"
    11  	"strings"
    12  	"time"
    13  	"unicode/utf8"
    14  )
    15  
    16  type encoder struct {
    17  	emitter yaml_emitter_t
    18  	event   yaml_event_t
    19  	out     []byte
    20  	flow    bool
    21  	// doneInit holds whether the initial stream_start_event has been
    22  	// emitted.
    23  	doneInit bool
    24  }
    25  
    26  func newEncoder() *encoder {
    27  	e := &encoder{}
    28  	yaml_emitter_initialize(&e.emitter)
    29  	yaml_emitter_set_output_string(&e.emitter, &e.out)
    30  	yaml_emitter_set_unicode(&e.emitter, true)
    31  	return e
    32  }
    33  
    34  func newEncoderWithWriter(w io.Writer) *encoder {
    35  	e := &encoder{}
    36  	yaml_emitter_initialize(&e.emitter)
    37  	yaml_emitter_set_output_writer(&e.emitter, w)
    38  	yaml_emitter_set_unicode(&e.emitter, true)
    39  	return e
    40  }
    41  
    42  func (e *encoder) init() {
    43  	if e.doneInit {
    44  		return
    45  	}
    46  	yaml_stream_start_event_initialize(&e.event, yaml_UTF8_ENCODING)
    47  	e.emit()
    48  	e.doneInit = true
    49  }
    50  
    51  func (e *encoder) finish() {
    52  	e.emitter.open_ended = false
    53  	yaml_stream_end_event_initialize(&e.event)
    54  	e.emit()
    55  }
    56  
    57  func (e *encoder) destroy() {
    58  	yaml_emitter_delete(&e.emitter)
    59  }
    60  
    61  func (e *encoder) emit() {
    62  	// This will internally delete the e.event value.
    63  	e.must(yaml_emitter_emit(&e.emitter, &e.event))
    64  }
    65  
    66  func (e *encoder) must(ok bool) {
    67  	if !ok {
    68  		msg := e.emitter.problem
    69  		if msg == "" {
    70  			msg = "unknown problem generating YAML content"
    71  		}
    72  		failf("%s", msg)
    73  	}
    74  }
    75  
    76  func (e *encoder) marshalDoc(tag string, in reflect.Value) {
    77  	e.init()
    78  	yaml_document_start_event_initialize(&e.event, nil, nil, true)
    79  	e.emit()
    80  	e.marshal(tag, in)
    81  	yaml_document_end_event_initialize(&e.event, true)
    82  	e.emit()
    83  }
    84  
    85  func (e *encoder) marshal(tag string, in reflect.Value) {
    86  	if !in.IsValid() || in.Kind() == reflect.Ptr && in.IsNil() {
    87  		e.nilv()
    88  		return
    89  	}
    90  	iface := in.Interface()
    91  	switch m := iface.(type) {
    92  	case time.Time, *time.Time:
    93  		// Although time.Time implements TextMarshaler,
    94  		// we don't want to treat it as a string for YAML
    95  		// purposes because YAML has special support for
    96  		// timestamps.
    97  	case Marshaler:
    98  		v, err := m.MarshalYAML()
    99  		if err != nil {
   100  			fail(err)
   101  		}
   102  		if v == nil {
   103  			e.nilv()
   104  			return
   105  		}
   106  		in = reflect.ValueOf(v)
   107  	case encoding.TextMarshaler:
   108  		text, err := m.MarshalText()
   109  		if err != nil {
   110  			fail(err)
   111  		}
   112  		in = reflect.ValueOf(string(text))
   113  	case nil:
   114  		e.nilv()
   115  		return
   116  	}
   117  	switch in.Kind() {
   118  	case reflect.Interface:
   119  		e.marshal(tag, in.Elem())
   120  	case reflect.Map:
   121  		e.mapv(tag, in)
   122  	case reflect.Ptr:
   123  		if in.Type() == ptrTimeType {
   124  			e.timev(tag, in.Elem())
   125  		} else {
   126  			e.marshal(tag, in.Elem())
   127  		}
   128  	case reflect.Struct:
   129  		if in.Type() == timeType {
   130  			e.timev(tag, in)
   131  		} else {
   132  			e.structv(tag, in)
   133  		}
   134  	case reflect.Slice, reflect.Array:
   135  		if in.Type().Elem() == mapItemType {
   136  			e.itemsv(tag, in)
   137  		} else {
   138  			e.slicev(tag, in)
   139  		}
   140  	case reflect.String:
   141  		e.stringv(tag, in)
   142  	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
   143  		if in.Type() == durationType {
   144  			e.stringv(tag, reflect.ValueOf(iface.(time.Duration).String()))
   145  		} else {
   146  			e.intv(tag, in)
   147  		}
   148  	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
   149  		e.uintv(tag, in)
   150  	case reflect.Float32, reflect.Float64:
   151  		e.floatv(tag, in)
   152  	case reflect.Bool:
   153  		e.boolv(tag, in)
   154  	default:
   155  		panic("cannot marshal type: " + in.Type().String())
   156  	}
   157  }
   158  
   159  func (e *encoder) mapv(tag string, in reflect.Value) {
   160  	e.mappingv(tag, func() {
   161  		keys := keyList(in.MapKeys())
   162  		sort.Sort(keys)
   163  		for _, k := range keys {
   164  			e.marshal("", k)
   165  			e.marshal("", in.MapIndex(k))
   166  		}
   167  	})
   168  }
   169  
   170  func (e *encoder) itemsv(tag string, in reflect.Value) {
   171  	e.mappingv(tag, func() {
   172  		slice := in.Convert(reflect.TypeOf([]MapItem{})).Interface().([]MapItem)
   173  		for _, item := range slice {
   174  			e.marshal("", reflect.ValueOf(item.Key))
   175  			e.marshal("", reflect.ValueOf(item.Value))
   176  		}
   177  	})
   178  }
   179  
   180  func (e *encoder) structv(tag string, in reflect.Value) {
   181  	sinfo, err := getStructInfo(in.Type())
   182  	if err != nil {
   183  		panic(err)
   184  	}
   185  	e.mappingv(tag, func() {
   186  		for _, info := range sinfo.FieldsList {
   187  			var value reflect.Value
   188  			if info.Inline == nil {
   189  				value = in.Field(info.Num)
   190  			} else {
   191  				value = in.FieldByIndex(info.Inline)
   192  			}
   193  			if info.OmitEmpty && isZero(value) {
   194  				continue
   195  			}
   196  			e.marshal("", reflect.ValueOf(info.Key))
   197  			e.flow = info.Flow
   198  			e.marshal("", value)
   199  		}
   200  		if sinfo.InlineMap >= 0 {
   201  			m := in.Field(sinfo.InlineMap)
   202  			if m.Len() > 0 {
   203  				e.flow = false
   204  				keys := keyList(m.MapKeys())
   205  				sort.Sort(keys)
   206  				for _, k := range keys {
   207  					if _, found := sinfo.FieldsMap[k.String()]; found {
   208  						panic(fmt.Sprintf("Can't have key %q in inlined map; conflicts with struct field", k.String()))
   209  					}
   210  					e.marshal("", k)
   211  					e.flow = false
   212  					e.marshal("", m.MapIndex(k))
   213  				}
   214  			}
   215  		}
   216  	})
   217  }
   218  
   219  func (e *encoder) mappingv(tag string, f func()) {
   220  	implicit := tag == ""
   221  	style := yaml_BLOCK_MAPPING_STYLE
   222  	if e.flow {
   223  		e.flow = false
   224  		style = yaml_FLOW_MAPPING_STYLE
   225  	}
   226  	yaml_mapping_start_event_initialize(&e.event, nil, []byte(tag), implicit, style)
   227  	e.emit()
   228  	f()
   229  	yaml_mapping_end_event_initialize(&e.event)
   230  	e.emit()
   231  }
   232  
   233  func (e *encoder) slicev(tag string, in reflect.Value) {
   234  	implicit := tag == ""
   235  	style := yaml_BLOCK_SEQUENCE_STYLE
   236  	if e.flow {
   237  		e.flow = false
   238  		style = yaml_FLOW_SEQUENCE_STYLE
   239  	}
   240  	e.must(yaml_sequence_start_event_initialize(&e.event, nil, []byte(tag), implicit, style))
   241  	e.emit()
   242  	n := in.Len()
   243  	for i := 0; i < n; i++ {
   244  		e.marshal("", in.Index(i))
   245  	}
   246  	e.must(yaml_sequence_end_event_initialize(&e.event))
   247  	e.emit()
   248  }
   249  
   250  // isBase60 returns whether s is in base 60 notation as defined in YAML 1.1.
   251  //
   252  // The base 60 float notation in YAML 1.1 is a terrible idea and is unsupported
   253  // in YAML 1.2 and by this package, but these should be marshalled quoted for
   254  // the time being for compatibility with other parsers.
   255  func isBase60Float(s string) (result bool) {
   256  	// Fast path.
   257  	if s == "" {
   258  		return false
   259  	}
   260  	c := s[0]
   261  	if !(c == '+' || c == '-' || c >= '0' && c <= '9') || strings.IndexByte(s, ':') < 0 {
   262  		return false
   263  	}
   264  	// Do the full match.
   265  	return base60float.MatchString(s)
   266  }
   267  
   268  // From http://yaml.org/type/float.html, except the regular expression there
   269  // is bogus. In practice parsers do not enforce the "\.[0-9_]*" suffix.
   270  var base60float = regexp.MustCompile(`^[-+]?[0-9][0-9_]*(?::[0-5]?[0-9])+(?:\.[0-9_]*)?$`)
   271  
   272  func (e *encoder) stringv(tag string, in reflect.Value) {
   273  	var style yaml_scalar_style_t
   274  	s := in.String()
   275  	canUsePlain := true
   276  	switch {
   277  	case !utf8.ValidString(s):
   278  		if tag == yaml_BINARY_TAG {
   279  			failf("explicitly tagged !!binary data must be base64-encoded")
   280  		}
   281  		if tag != "" {
   282  			failf("cannot marshal invalid UTF-8 data as %s", shortTag(tag))
   283  		}
   284  		// It can't be encoded directly as YAML so use a binary tag
   285  		// and encode it as base64.
   286  		tag = yaml_BINARY_TAG
   287  		s = encodeBase64(s)
   288  	case tag == "":
   289  		// Check to see if it would resolve to a specific
   290  		// tag when encoded unquoted. If it doesn't,
   291  		// there's no need to quote it.
   292  		rtag, _ := resolve("", s)
   293  		canUsePlain = rtag == yaml_STR_TAG && !isBase60Float(s)
   294  	}
   295  	// Note: it's possible for user code to emit invalid YAML
   296  	// if they explicitly specify a tag and a string containing
   297  	// text that's incompatible with that tag.
   298  	switch {
   299  	case strings.Contains(s, "\n"):
   300  		style = yaml_LITERAL_SCALAR_STYLE
   301  	case canUsePlain:
   302  		style = yaml_PLAIN_SCALAR_STYLE
   303  	default:
   304  		style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
   305  	}
   306  	e.emitScalar(s, "", tag, style)
   307  }
   308  
   309  func (e *encoder) boolv(tag string, in reflect.Value) {
   310  	var s string
   311  	if in.Bool() {
   312  		s = "true"
   313  	} else {
   314  		s = "false"
   315  	}
   316  	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
   317  }
   318  
   319  func (e *encoder) intv(tag string, in reflect.Value) {
   320  	s := strconv.FormatInt(in.Int(), 10)
   321  	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
   322  }
   323  
   324  func (e *encoder) uintv(tag string, in reflect.Value) {
   325  	s := strconv.FormatUint(in.Uint(), 10)
   326  	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
   327  }
   328  
   329  func (e *encoder) timev(tag string, in reflect.Value) {
   330  	t := in.Interface().(time.Time)
   331  	s := t.Format(time.RFC3339Nano)
   332  	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
   333  }
   334  
   335  func (e *encoder) floatv(tag string, in reflect.Value) {
   336  	// Issue #352: When formatting, use the precision of the underlying value
   337  	precision := 64
   338  	if in.Kind() == reflect.Float32 {
   339  		precision = 32
   340  	}
   341  
   342  	s := strconv.FormatFloat(in.Float(), 'g', -1, precision)
   343  	switch s {
   344  	case "+Inf":
   345  		s = ".inf"
   346  	case "-Inf":
   347  		s = "-.inf"
   348  	case "NaN":
   349  		s = ".nan"
   350  	}
   351  	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
   352  }
   353  
   354  func (e *encoder) nilv() {
   355  	e.emitScalar("null", "", "", yaml_PLAIN_SCALAR_STYLE)
   356  }
   357  
   358  func (e *encoder) emitScalar(value, anchor, tag string, style yaml_scalar_style_t) {
   359  	implicit := tag == ""
   360  	e.must(yaml_scalar_event_initialize(&e.event, []byte(anchor), []byte(tag), []byte(value), implicit, implicit, style))
   361  	e.emit()
   362  }