diff options
Diffstat (limited to 'vendor/gopkg.in/yaml.v2/resolve.go')
-rw-r--r-- | vendor/gopkg.in/yaml.v2/resolve.go | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/vendor/gopkg.in/yaml.v2/resolve.go b/vendor/gopkg.in/yaml.v2/resolve.go new file mode 100644 index 0000000..6c151db --- /dev/null +++ b/vendor/gopkg.in/yaml.v2/resolve.go @@ -0,0 +1,258 @@ +package yaml + +import ( + "encoding/base64" + "math" + "regexp" + "strconv" + "strings" + "time" +) + +type resolveMapItem struct { + value interface{} + tag string +} + +var resolveTable = make([]byte, 256) +var resolveMap = make(map[string]resolveMapItem) + +func init() { + t := resolveTable + t[int('+')] = 'S' // Sign + t[int('-')] = 'S' + for _, c := range "0123456789" { + t[int(c)] = 'D' // Digit + } + for _, c := range "yYnNtTfFoO~" { + t[int(c)] = 'M' // In map + } + t[int('.')] = '.' // Float (potentially in map) + + var resolveMapList = []struct { + v interface{} + tag string + l []string + }{ + {true, yaml_BOOL_TAG, []string{"y", "Y", "yes", "Yes", "YES"}}, + {true, yaml_BOOL_TAG, []string{"true", "True", "TRUE"}}, + {true, yaml_BOOL_TAG, []string{"on", "On", "ON"}}, + {false, yaml_BOOL_TAG, []string{"n", "N", "no", "No", "NO"}}, + {false, yaml_BOOL_TAG, []string{"false", "False", "FALSE"}}, + {false, yaml_BOOL_TAG, []string{"off", "Off", "OFF"}}, + {nil, yaml_NULL_TAG, []string{"", "~", "null", "Null", "NULL"}}, + {math.NaN(), yaml_FLOAT_TAG, []string{".nan", ".NaN", ".NAN"}}, + {math.Inf(+1), yaml_FLOAT_TAG, []string{".inf", ".Inf", ".INF"}}, + {math.Inf(+1), yaml_FLOAT_TAG, []string{"+.inf", "+.Inf", "+.INF"}}, + {math.Inf(-1), yaml_FLOAT_TAG, []string{"-.inf", "-.Inf", "-.INF"}}, + {"<<", yaml_MERGE_TAG, []string{"<<"}}, + } + + m := resolveMap + for _, item := range resolveMapList { + for _, s := range item.l { + m[s] = resolveMapItem{item.v, item.tag} + } + } +} + +const longTagPrefix = "tag:yaml.org,2002:" + +func shortTag(tag string) string { + // TODO This can easily be made faster and produce less garbage. + if strings.HasPrefix(tag, longTagPrefix) { + return "!!" + tag[len(longTagPrefix):] + } + return tag +} + +func longTag(tag string) string { + if strings.HasPrefix(tag, "!!") { + return longTagPrefix + tag[2:] + } + return tag +} + +func resolvableTag(tag string) bool { + switch tag { + case "", yaml_STR_TAG, yaml_BOOL_TAG, yaml_INT_TAG, yaml_FLOAT_TAG, yaml_NULL_TAG, yaml_TIMESTAMP_TAG: + return true + } + return false +} + +var yamlStyleFloat = regexp.MustCompile(`^[-+]?[0-9]*\.?[0-9]+([eE][-+][0-9]+)?$`) + +func resolve(tag string, in string) (rtag string, out interface{}) { + if !resolvableTag(tag) { + return tag, in + } + + defer func() { + switch tag { + case "", rtag, yaml_STR_TAG, yaml_BINARY_TAG: + return + case yaml_FLOAT_TAG: + if rtag == yaml_INT_TAG { + switch v := out.(type) { + case int64: + rtag = yaml_FLOAT_TAG + out = float64(v) + return + case int: + rtag = yaml_FLOAT_TAG + out = float64(v) + return + } + } + } + failf("cannot decode %s `%s` as a %s", shortTag(rtag), in, shortTag(tag)) + }() + + // Any data is accepted as a !!str or !!binary. + // Otherwise, the prefix is enough of a hint about what it might be. + hint := byte('N') + if in != "" { + hint = resolveTable[in[0]] + } + if hint != 0 && tag != yaml_STR_TAG && tag != yaml_BINARY_TAG { + // Handle things we can lookup in a map. + if item, ok := resolveMap[in]; ok { + return item.tag, item.value + } + + // Base 60 floats are a bad idea, were dropped in YAML 1.2, and + // are purposefully unsupported here. They're still quoted on + // the way out for compatibility with other parser, though. + + switch hint { + case 'M': + // We've already checked the map above. + + case '.': + // Not in the map, so maybe a normal float. + floatv, err := strconv.ParseFloat(in, 64) + if err == nil { + return yaml_FLOAT_TAG, floatv + } + + case 'D', 'S': + // Int, float, or timestamp. + // Only try values as a timestamp if the value is unquoted or there's an explicit + // !!timestamp tag. + if tag == "" || tag == yaml_TIMESTAMP_TAG { + t, ok := parseTimestamp(in) + if ok { + return yaml_TIMESTAMP_TAG, t + } + } + + plain := strings.Replace(in, "_", "", -1) + intv, err := strconv.ParseInt(plain, 0, 64) + if err == nil { + if intv == int64(int(intv)) { + return yaml_INT_TAG, int(intv) + } else { + return yaml_INT_TAG, intv + } + } + uintv, err := strconv.ParseUint(plain, 0, 64) + if err == nil { + return yaml_INT_TAG, uintv + } + if yamlStyleFloat.MatchString(plain) { + floatv, err := strconv.ParseFloat(plain, 64) + if err == nil { + return yaml_FLOAT_TAG, floatv + } + } + if strings.HasPrefix(plain, "0b") { + intv, err := strconv.ParseInt(plain[2:], 2, 64) + if err == nil { + if intv == int64(int(intv)) { + return yaml_INT_TAG, int(intv) + } else { + return yaml_INT_TAG, intv + } + } + uintv, err := strconv.ParseUint(plain[2:], 2, 64) + if err == nil { + return yaml_INT_TAG, uintv + } + } else if strings.HasPrefix(plain, "-0b") { + intv, err := strconv.ParseInt("-" + plain[3:], 2, 64) + if err == nil { + if true || intv == int64(int(intv)) { + return yaml_INT_TAG, int(intv) + } else { + return yaml_INT_TAG, intv + } + } + } + default: + panic("resolveTable item not yet handled: " + string(rune(hint)) + " (with " + in + ")") + } + } + return yaml_STR_TAG, in +} + +// encodeBase64 encodes s as base64 that is broken up into multiple lines +// as appropriate for the resulting length. +func encodeBase64(s string) string { + const lineLen = 70 + encLen := base64.StdEncoding.EncodedLen(len(s)) + lines := encLen/lineLen + 1 + buf := make([]byte, encLen*2+lines) + in := buf[0:encLen] + out := buf[encLen:] + base64.StdEncoding.Encode(in, []byte(s)) + k := 0 + for i := 0; i < len(in); i += lineLen { + j := i + lineLen + if j > len(in) { + j = len(in) + } + k += copy(out[k:], in[i:j]) + if lines > 1 { + out[k] = '\n' + k++ + } + } + return string(out[:k]) +} + +// This is a subset of the formats allowed by the regular expression +// defined at http://yaml.org/type/timestamp.html. +var allowedTimestampFormats = []string{ + "2006-1-2T15:4:5.999999999Z07:00", // RCF3339Nano with short date fields. + "2006-1-2t15:4:5.999999999Z07:00", // RFC3339Nano with short date fields and lower-case "t". + "2006-1-2 15:4:5.999999999", // space separated with no time zone + "2006-1-2", // date only + // Notable exception: time.Parse cannot handle: "2001-12-14 21:59:43.10 -5" + // from the set of examples. +} + +// parseTimestamp parses s as a timestamp string and +// returns the timestamp and reports whether it succeeded. +// Timestamp formats are defined at http://yaml.org/type/timestamp.html +func parseTimestamp(s string) (time.Time, bool) { + // TODO write code to check all the formats supported by + // http://yaml.org/type/timestamp.html instead of using time.Parse. + + // Quick check: all date formats start with YYYY-. + i := 0 + for ; i < len(s); i++ { + if c := s[i]; c < '0' || c > '9' { + break + } + } + if i != 4 || i == len(s) || s[i] != '-' { + return time.Time{}, false + } + for _, format := range allowedTimestampFormats { + if t, err := time.Parse(format, s); err == nil { + return t, true + } + } + return time.Time{}, false +} |