[chore] dependabot updates (#2922)

* [chore]: Bump github.com/prometheus/client_golang from 1.18.0 to 1.19.1

Bumps [github.com/prometheus/client_golang](https://github.com/prometheus/client_golang) from 1.18.0 to 1.19.1.
- [Release notes](https://github.com/prometheus/client_golang/releases)
- [Changelog](https://github.com/prometheus/client_golang/blob/main/CHANGELOG.md)
- [Commits](https://github.com/prometheus/client_golang/compare/v1.18.0...v1.19.1)

---
updated-dependencies:
- dependency-name: github.com/prometheus/client_golang
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

* [chore]: Bump github.com/KimMachineGun/automemlimit from 0.6.0 to 0.6.1

Bumps [github.com/KimMachineGun/automemlimit](https://github.com/KimMachineGun/automemlimit) from 0.6.0 to 0.6.1.
- [Release notes](https://github.com/KimMachineGun/automemlimit/releases)
- [Commits](https://github.com/KimMachineGun/automemlimit/compare/v0.6.0...v0.6.1)

---
updated-dependencies:
- dependency-name: github.com/KimMachineGun/automemlimit
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

* [chore]: Bump github.com/tdewolff/minify/v2 from 2.20.20 to 2.20.24

Bumps [github.com/tdewolff/minify/v2](https://github.com/tdewolff/minify) from 2.20.20 to 2.20.24.
- [Release notes](https://github.com/tdewolff/minify/releases)
- [Commits](https://github.com/tdewolff/minify/compare/v2.20.20...v2.20.24)

---
updated-dependencies:
- dependency-name: github.com/tdewolff/minify/v2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

* [chore]: Bump github.com/go-swagger/go-swagger

Bumps [github.com/go-swagger/go-swagger](https://github.com/go-swagger/go-swagger) from 0.30.6-0.20240418033037-c46c303aaa02 to 0.31.0.
- [Release notes](https://github.com/go-swagger/go-swagger/releases)
- [Changelog](https://github.com/go-swagger/go-swagger/blob/master/.goreleaser.yml)
- [Commits](https://github.com/go-swagger/go-swagger/commits/v0.31.0)

---
updated-dependencies:
- dependency-name: github.com/go-swagger/go-swagger
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

* [chore]: Bump github.com/gin-gonic/gin from 1.9.1 to 1.10.0

Bumps [github.com/gin-gonic/gin](https://github.com/gin-gonic/gin) from 1.9.1 to 1.10.0.
- [Release notes](https://github.com/gin-gonic/gin/releases)
- [Changelog](https://github.com/gin-gonic/gin/blob/master/CHANGELOG.md)
- [Commits](https://github.com/gin-gonic/gin/compare/v1.9.1...v1.10.0)

---
updated-dependencies:
- dependency-name: github.com/gin-gonic/gin
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

8 files changed, 422 insertions, 38 deletions

diff --git a/vendor/github.com/prometheus/common/model/alert.go b/vendor/github.com/prometheus/common/model/alert.go
index 35e739c7a..178fdbaf6 100644
--- a/vendor/github.com/prometheus/common/model/alert.go
+++ b/vendor/github.com/prometheus/common/model/alert.go
@@ -90,13 +90,13 @@ func (a *Alert) Validate() error {
 		return fmt.Errorf("start time must be before end time")
 	}
 	if err := a.Labels.Validate(); err != nil {
-		return fmt.Errorf("invalid label set: %s", err)
+		return fmt.Errorf("invalid label set: %w", err)
 	}
 	if len(a.Labels) == 0 {
 		return fmt.Errorf("at least one label pair required")
 	}
 	if err := a.Annotations.Validate(); err != nil {
-		return fmt.Errorf("invalid annotations: %s", err)
+		return fmt.Errorf("invalid annotations: %w", err)
 	}
 	return nil
 }
diff --git a/vendor/github.com/prometheus/common/model/labels.go b/vendor/github.com/prometheus/common/model/labels.go
index ef8956335..3317ce22f 100644
--- a/vendor/github.com/prometheus/common/model/labels.go
+++ b/vendor/github.com/prometheus/common/model/labels.go
@@ -97,17 +97,25 @@ var LabelNameRE = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
 // therewith.
 type LabelName string
 
-// IsValid is true iff the label name matches the pattern of LabelNameRE. This
-// method, however, does not use LabelNameRE for the check but a much faster
-// hardcoded implementation.
+// IsValid returns true iff name matches the pattern of LabelNameRE for legacy
+// names, and iff it's valid UTF-8 if NameValidationScheme is set to
+// UTF8Validation. For the legacy matching, it does not use LabelNameRE for the
+// check but a much faster hardcoded implementation.
 func (ln LabelName) IsValid() bool {
 	if len(ln) == 0 {
 		return false
 	}
-	for i, b := range ln {
-		if !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || (b >= '0' && b <= '9' && i > 0)) {
-			return false
+	switch NameValidationScheme {
+	case LegacyValidation:
+		for i, b := range ln {
+			if !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || (b >= '0' && b <= '9' && i > 0)) {
+				return false
+			}
 		}
+	case UTF8Validation:
+		return utf8.ValidString(string(ln))
+	default:
+		panic(fmt.Sprintf("Invalid name validation scheme requested: %d", NameValidationScheme))
 	}
 	return true
 }
@@ -164,7 +172,7 @@ func (l LabelNames) String() string {
 // A LabelValue is an associated value for a LabelName.
 type LabelValue string
 
-// IsValid returns true iff the string is a valid UTF8.
+// IsValid returns true iff the string is a valid UTF-8.
 func (lv LabelValue) IsValid() bool {
 	return utf8.ValidString(string(lv))
 }
diff --git a/vendor/github.com/prometheus/common/model/metadata.go b/vendor/github.com/prometheus/common/model/metadata.go
new file mode 100644
index 000000000..447ab8ad6
--- /dev/null
+++ b/vendor/github.com/prometheus/common/model/metadata.go
@@ -0,0 +1,28 @@
+// Copyright 2023 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+// MetricType represents metric type values.
+type MetricType string
+
+const (
+	MetricTypeCounter        = MetricType("counter")
+	MetricTypeGauge          = MetricType("gauge")
+	MetricTypeHistogram      = MetricType("histogram")
+	MetricTypeGaugeHistogram = MetricType("gaugehistogram")
+	MetricTypeSummary        = MetricType("summary")
+	MetricTypeInfo           = MetricType("info")
+	MetricTypeStateset       = MetricType("stateset")
+	MetricTypeUnknown        = MetricType("unknown")
+)
diff --git a/vendor/github.com/prometheus/common/model/metric.go b/vendor/github.com/prometheus/common/model/metric.go
index 00804b7fe..0bd29b3a3 100644
--- a/vendor/github.com/prometheus/common/model/metric.go
+++ b/vendor/github.com/prometheus/common/model/metric.go
@@ -18,15 +18,84 @@ import (
 	"regexp"
 	"sort"
 	"strings"
+	"unicode/utf8"
+
+	dto "github.com/prometheus/client_model/go"
+	"google.golang.org/protobuf/proto"
 )
 
 var (
-	// MetricNameRE is a regular expression matching valid metric
-	// names. Note that the IsValidMetricName function performs the same
-	// check but faster than a match with this regular expression.
-	MetricNameRE = regexp.MustCompile(`^[a-zA-Z_:][a-zA-Z0-9_:]*$`)
+	// NameValidationScheme determines the method of name validation to be used by
+	// all calls to IsValidMetricName() and LabelName IsValid(). Setting UTF-8 mode
+	// in isolation from other components that don't support UTF-8 may result in
+	// bugs or other undefined behavior. This value is intended to be set by
+	// UTF-8-aware binaries as part of their startup. To avoid need for locking,
+	// this value should be set once, ideally in an init(), before multiple
+	// goroutines are started.
+	NameValidationScheme = LegacyValidation
+
+	// NameEscapingScheme defines the default way that names will be
+	// escaped when presented to systems that do not support UTF-8 names. If the
+	// Content-Type "escaping" term is specified, that will override this value.
+	NameEscapingScheme = ValueEncodingEscaping
+)
+
+// ValidationScheme is a Go enum for determining how metric and label names will
+// be validated by this library.
+type ValidationScheme int
+
+const (
+	// LegacyValidation is a setting that requirets that metric and label names
+	// conform to the original Prometheus character requirements described by
+	// MetricNameRE and LabelNameRE.
+	LegacyValidation ValidationScheme = iota
+
+	// UTF8Validation only requires that metric and label names be valid UTF-8
+	// strings.
+	UTF8Validation
+)
+
+type EscapingScheme int
+
+const (
+	// NoEscaping indicates that a name will not be escaped. Unescaped names that
+	// do not conform to the legacy validity check will use a new exposition
+	// format syntax that will be officially standardized in future versions.
+	NoEscaping EscapingScheme = iota
+
+	// UnderscoreEscaping replaces all legacy-invalid characters with underscores.
+	UnderscoreEscaping
+
+	// DotsEscaping is similar to UnderscoreEscaping, except that dots are
+	// converted to `_dot_` and pre-existing underscores are converted to `__`.
+	DotsEscaping
+
+	// ValueEncodingEscaping prepends the name with `U__` and replaces all invalid
+	// characters with the unicode value, surrounded by underscores. Single
+	// underscores are replaced with double underscores.
+	ValueEncodingEscaping
+)
+
+const (
+	// EscapingKey is the key in an Accept or Content-Type header that defines how
+	// metric and label names that do not conform to the legacy character
+	// requirements should be escaped when being scraped by a legacy prometheus
+	// system. If a system does not explicitly pass an escaping parameter in the
+	// Accept header, the default NameEscapingScheme will be used.
+	EscapingKey = "escaping"
+
+	// Possible values for Escaping Key:
+	AllowUTF8         = "allow-utf-8" // No escaping required.
+	EscapeUnderscores = "underscores"
+	EscapeDots        = "dots"
+	EscapeValues      = "values"
 )
 
+// MetricNameRE is a regular expression matching valid metric
+// names. Note that the IsValidMetricName function performs the same
+// check but faster than a match with this regular expression.
+var MetricNameRE = regexp.MustCompile(`^[a-zA-Z_:][a-zA-Z0-9_:]*$`)
+
 // A Metric is similar to a LabelSet, but the key difference is that a Metric is
 // a singleton and refers to one and only one stream of samples.
 type Metric LabelSet
@@ -86,17 +155,302 @@ func (m Metric) FastFingerprint() Fingerprint {
 	return LabelSet(m).FastFingerprint()
 }
 
-// IsValidMetricName returns true iff name matches the pattern of MetricNameRE.
+// IsValidMetricName returns true iff name matches the pattern of MetricNameRE
+// for legacy names, and iff it's valid UTF-8 if the UTF8Validation scheme is
+// selected.
+func IsValidMetricName(n LabelValue) bool {
+	switch NameValidationScheme {
+	case LegacyValidation:
+		return IsValidLegacyMetricName(n)
+	case UTF8Validation:
+		if len(n) == 0 {
+			return false
+		}
+		return utf8.ValidString(string(n))
+	default:
+		panic(fmt.Sprintf("Invalid name validation scheme requested: %d", NameValidationScheme))
+	}
+}
+
+// IsValidLegacyMetricName is similar to IsValidMetricName but always uses the
+// legacy validation scheme regardless of the value of NameValidationScheme.
 // This function, however, does not use MetricNameRE for the check but a much
 // faster hardcoded implementation.
-func IsValidMetricName(n LabelValue) bool {
+func IsValidLegacyMetricName(n LabelValue) bool {
 	if len(n) == 0 {
 		return false
 	}
 	for i, b := range n {
-		if !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || b == ':' || (b >= '0' && b <= '9' && i > 0)) {
+		if !isValidLegacyRune(b, i) {
 			return false
 		}
 	}
 	return true
 }
+
+// EscapeMetricFamily escapes the given metric names and labels with the given
+// escaping scheme. Returns a new object that uses the same pointers to fields
+// when possible and creates new escaped versions so as not to mutate the
+// input.
+func EscapeMetricFamily(v *dto.MetricFamily, scheme EscapingScheme) *dto.MetricFamily {
+	if v == nil {
+		return nil
+	}
+
+	if scheme == NoEscaping {
+		return v
+	}
+
+	out := &dto.MetricFamily{
+		Help: v.Help,
+		Type: v.Type,
+	}
+
+	// If the name is nil, copy as-is, don't try to escape.
+	if v.Name == nil || IsValidLegacyMetricName(LabelValue(v.GetName())) {
+		out.Name = v.Name
+	} else {
+		out.Name = proto.String(EscapeName(v.GetName(), scheme))
+	}
+	for _, m := range v.Metric {
+		if !metricNeedsEscaping(m) {
+			out.Metric = append(out.Metric, m)
+			continue
+		}
+
+		escaped := &dto.Metric{
+			Gauge:       m.Gauge,
+			Counter:     m.Counter,
+			Summary:     m.Summary,
+			Untyped:     m.Untyped,
+			Histogram:   m.Histogram,
+			TimestampMs: m.TimestampMs,
+		}
+
+		for _, l := range m.Label {
+			if l.GetName() == MetricNameLabel {
+				if l.Value == nil || IsValidLegacyMetricName(LabelValue(l.GetValue())) {
+					escaped.Label = append(escaped.Label, l)
+					continue
+				}
+				escaped.Label = append(escaped.Label, &dto.LabelPair{
+					Name:  proto.String(MetricNameLabel),
+					Value: proto.String(EscapeName(l.GetValue(), scheme)),
+				})
+				continue
+			}
+			if l.Name == nil || IsValidLegacyMetricName(LabelValue(l.GetName())) {
+				escaped.Label = append(escaped.Label, l)
+				continue
+			}
+			escaped.Label = append(escaped.Label, &dto.LabelPair{
+				Name:  proto.String(EscapeName(l.GetName(), scheme)),
+				Value: l.Value,
+			})
+		}
+		out.Metric = append(out.Metric, escaped)
+	}
+	return out
+}
+
+func metricNeedsEscaping(m *dto.Metric) bool {
+	for _, l := range m.Label {
+		if l.GetName() == MetricNameLabel && !IsValidLegacyMetricName(LabelValue(l.GetValue())) {
+			return true
+		}
+		if !IsValidLegacyMetricName(LabelValue(l.GetName())) {
+			return true
+		}
+	}
+	return false
+}
+
+const (
+	lowerhex = "0123456789abcdef"
+)
+
+// EscapeName escapes the incoming name according to the provided escaping
+// scheme. Depending on the rules of escaping, this may cause no change in the
+// string that is returned. (Especially NoEscaping, which by definition is a
+// noop). This function does not do any validation of the name.
+func EscapeName(name string, scheme EscapingScheme) string {
+	if len(name) == 0 {
+		return name
+	}
+	var escaped strings.Builder
+	switch scheme {
+	case NoEscaping:
+		return name
+	case UnderscoreEscaping:
+		if IsValidLegacyMetricName(LabelValue(name)) {
+			return name
+		}
+		for i, b := range name {
+			if isValidLegacyRune(b, i) {
+				escaped.WriteRune(b)
+			} else {
+				escaped.WriteRune('_')
+			}
+		}
+		return escaped.String()
+	case DotsEscaping:
+		// Do not early return for legacy valid names, we still escape underscores.
+		for i, b := range name {
+			if b == '_' {
+				escaped.WriteString("__")
+			} else if b == '.' {
+				escaped.WriteString("_dot_")
+			} else if isValidLegacyRune(b, i) {
+				escaped.WriteRune(b)
+			} else {
+				escaped.WriteRune('_')
+			}
+		}
+		return escaped.String()
+	case ValueEncodingEscaping:
+		if IsValidLegacyMetricName(LabelValue(name)) {
+			return name
+		}
+		escaped.WriteString("U__")
+		for i, b := range name {
+			if isValidLegacyRune(b, i) {
+				escaped.WriteRune(b)
+			} else if !utf8.ValidRune(b) {
+				escaped.WriteString("_FFFD_")
+			} else if b < 0x100 {
+				escaped.WriteRune('_')
+				for s := 4; s >= 0; s -= 4 {
+					escaped.WriteByte(lowerhex[b>>uint(s)&0xF])
+				}
+				escaped.WriteRune('_')
+			} else if b < 0x10000 {
+				escaped.WriteRune('_')
+				for s := 12; s >= 0; s -= 4 {
+					escaped.WriteByte(lowerhex[b>>uint(s)&0xF])
+				}
+				escaped.WriteRune('_')
+			}
+		}
+		return escaped.String()
+	default:
+		panic(fmt.Sprintf("invalid escaping scheme %d", scheme))
+	}
+}
+
+// lower function taken from strconv.atoi
+func lower(c byte) byte {
+	return c | ('x' - 'X')
+}
+
+// UnescapeName unescapes the incoming name according to the provided escaping
+// scheme if possible. Some schemes are partially or totally non-roundtripable.
+// If any error is enountered, returns the original input.
+func UnescapeName(name string, scheme EscapingScheme) string {
+	if len(name) == 0 {
+		return name
+	}
+	switch scheme {
+	case NoEscaping:
+		return name
+	case UnderscoreEscaping:
+		// It is not possible to unescape from underscore replacement.
+		return name
+	case DotsEscaping:
+		name = strings.ReplaceAll(name, "_dot_", ".")
+		name = strings.ReplaceAll(name, "__", "_")
+		return name
+	case ValueEncodingEscaping:
+		escapedName, found := strings.CutPrefix(name, "U__")
+		if !found {
+			return name
+		}
+
+		var unescaped strings.Builder
+	TOP:
+		for i := 0; i < len(escapedName); i++ {
+			// All non-underscores are treated normally.
+			if escapedName[i] != '_' {
+				unescaped.WriteByte(escapedName[i])
+				continue
+			}
+			i++
+			if i >= len(escapedName) {
+				return name
+			}
+			// A double underscore is a single underscore.
+			if escapedName[i] == '_' {
+				unescaped.WriteByte('_')
+				continue
+			}
+			// We think we are in a UTF-8 code, process it.
+			var utf8Val uint
+			for j := 0; i < len(escapedName); j++ {
+				// This is too many characters for a utf8 value.
+				if j > 4 {
+					return name
+				}
+				// Found a closing underscore, convert to a rune, check validity, and append.
+				if escapedName[i] == '_' {
+					utf8Rune := rune(utf8Val)
+					if !utf8.ValidRune(utf8Rune) {
+						return name
+					}
+					unescaped.WriteRune(utf8Rune)
+					continue TOP
+				}
+				r := lower(escapedName[i])
+				utf8Val *= 16
+				if r >= '0' && r <= '9' {
+					utf8Val += uint(r) - '0'
+				} else if r >= 'a' && r <= 'f' {
+					utf8Val += uint(r) - 'a' + 10
+				} else {
+					return name
+				}
+				i++
+			}
+			// Didn't find closing underscore, invalid.
+			return name
+		}
+		return unescaped.String()
+	default:
+		panic(fmt.Sprintf("invalid escaping scheme %d", scheme))
+	}
+}
+
+func isValidLegacyRune(b rune, i int) bool {
+	return (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || b == ':' || (b >= '0' && b <= '9' && i > 0)
+}
+
+func (e EscapingScheme) String() string {
+	switch e {
+	case NoEscaping:
+		return AllowUTF8
+	case UnderscoreEscaping:
+		return EscapeUnderscores
+	case DotsEscaping:
+		return EscapeDots
+	case ValueEncodingEscaping:
+		return EscapeValues
+	default:
+		panic(fmt.Sprintf("unknown format scheme %d", e))
+	}
+}
+
+func ToEscapingScheme(s string) (EscapingScheme, error) {
+	if s == "" {
+		return NoEscaping, fmt.Errorf("got empty string instead of escaping scheme")
+	}
+	switch s {
+	case AllowUTF8:
+		return NoEscaping, nil
+	case EscapeUnderscores:
+		return UnderscoreEscaping, nil
+	case EscapeDots:
+		return DotsEscaping, nil
+	case EscapeValues:
+		return ValueEncodingEscaping, nil
+	default:
+		return NoEscaping, fmt.Errorf("unknown format scheme " + s)
+	}
+}
diff --git a/vendor/github.com/prometheus/common/model/signature.go b/vendor/github.com/prometheus/common/model/signature.go
index 8762b13c6..dc8a0026c 100644
--- a/vendor/github.com/prometheus/common/model/signature.go
+++ b/vendor/github.com/prometheus/common/model/signature.go
@@ -22,10 +22,8 @@ import (
 // when calculating their combined hash value (aka signature aka fingerprint).
 const SeparatorByte byte = 255
 
-var (
-	// cache the signature of an empty label set.
-	emptyLabelSignature = hashNew()
-)
+// cache the signature of an empty label set.
+var emptyLabelSignature = hashNew()
 
 // LabelsToSignature returns a quasi-unique signature (i.e., fingerprint) for a
 // given label set. (Collisions are possible but unlikely if the number of label
diff --git a/vendor/github.com/prometheus/common/model/silence.go b/vendor/github.com/prometheus/common/model/silence.go
index bb99889d2..910b0b71f 100644
--- a/vendor/github.com/prometheus/common/model/silence.go
+++ b/vendor/github.com/prometheus/common/model/silence.go
@@ -81,7 +81,7 @@ func (s *Silence) Validate() error {
 	}
 	for _, m := range s.Matchers {
 		if err := m.Validate(); err != nil {
-			return fmt.Errorf("invalid matcher: %s", err)
+			return fmt.Errorf("invalid matcher: %w", err)
 		}
 	}
 	if s.StartsAt.IsZero() {
diff --git a/vendor/github.com/prometheus/common/model/value.go b/vendor/github.com/prometheus/common/model/value.go
index 9eb440413..8050637d8 100644
--- a/vendor/github.com/prometheus/common/model/value.go
+++ b/vendor/github.com/prometheus/common/model/value.go
@@ -21,14 +21,12 @@ import (
 	"strings"
 )
 
-var (
-	// ZeroSample is the pseudo zero-value of Sample used to signal a
-	// non-existing sample. It is a Sample with timestamp Earliest, value 0.0,
-	// and metric nil. Note that the natural zero value of Sample has a timestamp
-	// of 0, which is possible to appear in a real Sample and thus not suitable
-	// to signal a non-existing Sample.
-	ZeroSample = Sample{Timestamp: Earliest}
-)
+// ZeroSample is the pseudo zero-value of Sample used to signal a
+// non-existing sample. It is a Sample with timestamp Earliest, value 0.0,
+// and metric nil. Note that the natural zero value of Sample has a timestamp
+// of 0, which is possible to appear in a real Sample and thus not suitable
+// to signal a non-existing Sample.
+var ZeroSample = Sample{Timestamp: Earliest}
 
 // Sample is a sample pair associated with a metric. A single sample must either
 // define Value or Histogram but not both. Histogram == nil implies the Value
@@ -274,7 +272,7 @@ func (s *Scalar) UnmarshalJSON(b []byte) error {
 
 	value, err := strconv.ParseFloat(f, 64)
 	if err != nil {
-		return fmt.Errorf("error parsing sample value: %s", err)
+		return fmt.Errorf("error parsing sample value: %w", err)
 	}
 	s.Value = SampleValue(value)
 	return nil
diff --git a/vendor/github.com/prometheus/common/model/value_float.go b/vendor/github.com/prometheus/common/model/value_float.go
index 0f615a705..ae35cc2ab 100644
--- a/vendor/github.com/prometheus/common/model/value_float.go
+++ b/vendor/github.com/prometheus/common/model/value_float.go
@@ -20,14 +20,12 @@ import (
 	"strconv"
 )
 
-var (
-	// ZeroSamplePair is the pseudo zero-value of SamplePair used to signal a
-	// non-existing sample pair. It is a SamplePair with timestamp Earliest and
-	// value 0.0. Note that the natural zero value of SamplePair has a timestamp
-	// of 0, which is possible to appear in a real SamplePair and thus not
-	// suitable to signal a non-existing SamplePair.
-	ZeroSamplePair = SamplePair{Timestamp: Earliest}
-)
+// ZeroSamplePair is the pseudo zero-value of SamplePair used to signal a
+// non-existing sample pair. It is a SamplePair with timestamp Earliest and
+// value 0.0. Note that the natural zero value of SamplePair has a timestamp
+// of 0, which is possible to appear in a real SamplePair and thus not
+// suitable to signal a non-existing SamplePair.
+var ZeroSamplePair = SamplePair{Timestamp: Earliest}
 
 // A SampleValue is a representation of a value for a given sample at a given
 // time.