Format with Go 1.19 formatter (#304)

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diff --git a/cmp/cmpopts/equate.go b/cmp/cmpopts/equate.go
index c49a756..e54a76c 100644
--- a/cmp/cmpopts/equate.go
+++ b/cmp/cmpopts/equate.go
@@ -42,6 +42,7 @@
 // The fraction and margin must be non-negative.
 //
 // The mathematical expression used is equivalent to:
+//
 //	|x-y| ≤ max(fraction*min(|x|, |y|), margin)
 //
 // EquateApprox can be used in conjunction with EquateNaNs.
diff --git a/cmp/cmpopts/sort.go b/cmp/cmpopts/sort.go
index a646d74..0eb2a75 100644
--- a/cmp/cmpopts/sort.go
+++ b/cmp/cmpopts/sort.go
@@ -18,9 +18,9 @@
 // sort any slice with element type V that is assignable to T.
 //
 // The less function must be:
-//	• Deterministic: less(x, y) == less(x, y)
-//	• Irreflexive: !less(x, x)
-//	• Transitive: if !less(x, y) and !less(y, z), then !less(x, z)
+//   - Deterministic: less(x, y) == less(x, y)
+//   - Irreflexive: !less(x, x)
+//   - Transitive: if !less(x, y) and !less(y, z), then !less(x, z)
 //
 // The less function does not have to be "total". That is, if !less(x, y) and
 // !less(y, x) for two elements x and y, their relative order is maintained.
@@ -91,10 +91,10 @@
 // use Comparers on K or the K.Equal method if it exists.
 //
 // The less function must be:
-//	• Deterministic: less(x, y) == less(x, y)
-//	• Irreflexive: !less(x, x)
-//	• Transitive: if !less(x, y) and !less(y, z), then !less(x, z)
-//	• Total: if x != y, then either less(x, y) or less(y, x)
+//   - Deterministic: less(x, y) == less(x, y)
+//   - Irreflexive: !less(x, x)
+//   - Transitive: if !less(x, y) and !less(y, z), then !less(x, z)
+//   - Total: if x != y, then either less(x, y) or less(y, x)
 //
 // SortMaps can be used in conjunction with EquateEmpty.
 func SortMaps(lessFunc interface{}) cmp.Option {
diff --git a/cmp/cmpopts/struct_filter.go b/cmp/cmpopts/struct_filter.go
index a09829c..ca11a40 100644
--- a/cmp/cmpopts/struct_filter.go
+++ b/cmp/cmpopts/struct_filter.go
@@ -67,12 +67,14 @@
 // fieldTree represents a set of dot-separated identifiers.
 //
 // For example, inserting the following selectors:
+//
 //	Foo
 //	Foo.Bar.Baz
 //	Foo.Buzz
 //	Nuka.Cola.Quantum
 //
 // Results in a tree of the form:
+//
 //	{sub: {
 //		"Foo": {ok: true, sub: {
 //			"Bar": {sub: {
diff --git a/cmp/cmpopts/xform.go b/cmp/cmpopts/xform.go
index 4eb49d6..8812443 100644
--- a/cmp/cmpopts/xform.go
+++ b/cmp/cmpopts/xform.go
@@ -23,6 +23,7 @@
 // that the transformer cannot be recursively applied upon its own output.
 //
 // An example use case is a transformer that splits a string by lines:
+//
 //	AcyclicTransformer("SplitLines", func(s string) []string{
 //		return strings.Split(s, "\n")
 //	})
diff --git a/cmp/compare.go b/cmp/compare.go
index fd2b3a4..caf75ad 100644
--- a/cmp/compare.go
+++ b/cmp/compare.go
@@ -13,21 +13,21 @@
 //
 // The primary features of cmp are:
 //
-// • When the default behavior of equality does not suit the needs of the test,
-// custom equality functions can override the equality operation.
-// For example, an equality function may report floats as equal so long as they
-// are within some tolerance of each other.
+//   - When the default behavior of equality does not suit the test's needs,
+//     custom equality functions can override the equality operation.
+//     For example, an equality function may report floats as equal so long as
+//     they are within some tolerance of each other.
 //
-// • Types that have an Equal method may use that method to determine equality.
-// This allows package authors to determine the equality operation for the types
-// that they define.
+//   - Types with an Equal method may use that method to determine equality.
+//     This allows package authors to determine the equality operation
+//     for the types that they define.
 //
-// • If no custom equality functions are used and no Equal method is defined,
-// equality is determined by recursively comparing the primitive kinds on both
-// values, much like reflect.DeepEqual. Unlike reflect.DeepEqual, unexported
-// fields are not compared by default; they result in panics unless suppressed
-// by using an Ignore option (see cmpopts.IgnoreUnexported) or explicitly
-// compared using the Exporter option.
+//   - If no custom equality functions are used and no Equal method is defined,
+//     equality is determined by recursively comparing the primitive kinds on
+//     both values, much like reflect.DeepEqual. Unlike reflect.DeepEqual,
+//     unexported fields are not compared by default; they result in panics
+//     unless suppressed by using an Ignore option (see cmpopts.IgnoreUnexported)
+//     or explicitly compared using the Exporter option.
 package cmp
 
 import (
@@ -45,25 +45,25 @@
 // Equal reports whether x and y are equal by recursively applying the
 // following rules in the given order to x and y and all of their sub-values:
 //
-// • Let S be the set of all Ignore, Transformer, and Comparer options that
-// remain after applying all path filters, value filters, and type filters.
-// If at least one Ignore exists in S, then the comparison is ignored.
-// If the number of Transformer and Comparer options in S is greater than one,
-// then Equal panics because it is ambiguous which option to use.
-// If S contains a single Transformer, then use that to transform the current
-// values and recursively call Equal on the output values.
-// If S contains a single Comparer, then use that to compare the current values.
-// Otherwise, evaluation proceeds to the next rule.
+//   - Let S be the set of all Ignore, Transformer, and Comparer options that
+//     remain after applying all path filters, value filters, and type filters.
+//     If at least one Ignore exists in S, then the comparison is ignored.
+//     If the number of Transformer and Comparer options in S is non-zero,
+//     then Equal panics because it is ambiguous which option to use.
+//     If S contains a single Transformer, then use that to transform
+//     the current values and recursively call Equal on the output values.
+//     If S contains a single Comparer, then use that to compare the current values.
+//     Otherwise, evaluation proceeds to the next rule.
 //
-// • If the values have an Equal method of the form "(T) Equal(T) bool" or
-// "(T) Equal(I) bool" where T is assignable to I, then use the result of
-// x.Equal(y) even if x or y is nil. Otherwise, no such method exists and
-// evaluation proceeds to the next rule.
+//   - If the values have an Equal method of the form "(T) Equal(T) bool" or
+//     "(T) Equal(I) bool" where T is assignable to I, then use the result of
+//     x.Equal(y) even if x or y is nil. Otherwise, no such method exists and
+//     evaluation proceeds to the next rule.
 //
-// • Lastly, try to compare x and y based on their basic kinds.
-// Simple kinds like booleans, integers, floats, complex numbers, strings, and
-// channels are compared using the equivalent of the == operator in Go.
-// Functions are only equal if they are both nil, otherwise they are unequal.
+//   - Lastly, try to compare x and y based on their basic kinds.
+//     Simple kinds like booleans, integers, floats, complex numbers, strings,
+//     and channels are compared using the equivalent of the == operator in Go.
+//     Functions are only equal if they are both nil, otherwise they are unequal.
 //
 // Structs are equal if recursively calling Equal on all fields report equal.
 // If a struct contains unexported fields, Equal panics unless an Ignore option
@@ -639,7 +639,9 @@
 // Next increments the state and reports whether a check should be performed.
 //
 // Checks occur every Nth function call, where N is a triangular number:
+//
 //	0 1 3 6 10 15 21 28 36 45 55 66 78 91 105 120 136 153 171 190 ...
+//
 // See https://en.wikipedia.org/wiki/Triangular_number
 //
 // This sequence ensures that the cost of checks drops significantly as
diff --git a/cmp/compare_test.go b/cmp/compare_test.go
index aafe441..dc86f01 100644
--- a/cmp/compare_test.go
+++ b/cmp/compare_test.go
@@ -43,7 +43,7 @@
 const goldenHeaderPrefix = "<<< "
 const goldenFooterPrefix = ">>> "
 
-/// mustParseGolden parses a file as a set of key-value pairs.
+// mustParseGolden parses a file as a set of key-value pairs.
 //
 // The syntax is simple and looks something like:
 //
diff --git a/cmp/internal/diff/diff.go b/cmp/internal/diff/diff.go
index bc196b1..a248e54 100644
--- a/cmp/internal/diff/diff.go
+++ b/cmp/internal/diff/diff.go
@@ -127,9 +127,9 @@
 // This function returns an edit-script, which is a sequence of operations
 // needed to convert one list into the other. The following invariants for
 // the edit-script are maintained:
-//	• eq == (es.Dist()==0)
-//	• nx == es.LenX()
-//	• ny == es.LenY()
+//   - eq == (es.Dist()==0)
+//   - nx == es.LenX()
+//   - ny == es.LenY()
 //
 // This algorithm is not guaranteed to be an optimal solution (i.e., one that
 // produces an edit-script with a minimal Levenshtein distance). This algorithm
@@ -169,12 +169,13 @@
 	// A diagonal edge is equivalent to a matching symbol between both X and Y.
 
 	// Invariants:
-	//	• 0 ≤ fwdPath.X ≤ (fwdFrontier.X, revFrontier.X) ≤ revPath.X ≤ nx
-	//	• 0 ≤ fwdPath.Y ≤ (fwdFrontier.Y, revFrontier.Y) ≤ revPath.Y ≤ ny
+	//   - 0 ≤ fwdPath.X ≤ (fwdFrontier.X, revFrontier.X) ≤ revPath.X ≤ nx
+	//   - 0 ≤ fwdPath.Y ≤ (fwdFrontier.Y, revFrontier.Y) ≤ revPath.Y ≤ ny
 	//
 	// In general:
-	//	• fwdFrontier.X < revFrontier.X
-	//	• fwdFrontier.Y < revFrontier.Y
+	//   - fwdFrontier.X < revFrontier.X
+	//   - fwdFrontier.Y < revFrontier.Y
+	//
 	// Unless, it is time for the algorithm to terminate.
 	fwdPath := path{+1, point{0, 0}, make(EditScript, 0, (nx+ny)/2)}
 	revPath := path{-1, point{nx, ny}, make(EditScript, 0)}
@@ -195,19 +196,21 @@
 	// computing sub-optimal edit-scripts between two lists.
 	//
 	// The algorithm is approximately as follows:
-	//	• Searching for differences switches back-and-forth between
-	//	a search that starts at the beginning (the top-left corner), and
-	//	a search that starts at the end (the bottom-right corner). The goal of
-	//	the search is connect with the search from the opposite corner.
-	//	• As we search, we build a path in a greedy manner, where the first
-	//	match seen is added to the path (this is sub-optimal, but provides a
-	//	decent result in practice). When matches are found, we try the next pair
-	//	of symbols in the lists and follow all matches as far as possible.
-	//	• When searching for matches, we search along a diagonal going through
-	//	through the "frontier" point. If no matches are found, we advance the
-	//	frontier towards the opposite corner.
-	//	• This algorithm terminates when either the X coordinates or the
-	//	Y coordinates of the forward and reverse frontier points ever intersect.
+	//   - Searching for differences switches back-and-forth between
+	//     a search that starts at the beginning (the top-left corner), and
+	//     a search that starts at the end (the bottom-right corner).
+	//     The goal of the search is connect with the search
+	//     from the opposite corner.
+	//   - As we search, we build a path in a greedy manner,
+	//     where the first match seen is added to the path (this is sub-optimal,
+	//     but provides a decent result in practice). When matches are found,
+	//     we try the next pair of symbols in the lists and follow all matches
+	//     as far as possible.
+	//   - When searching for matches, we search along a diagonal going through
+	//     through the "frontier" point. If no matches are found,
+	//     we advance the frontier towards the opposite corner.
+	//   - This algorithm terminates when either the X coordinates or the
+	//     Y coordinates of the forward and reverse frontier points ever intersect.
 
 	// This algorithm is correct even if searching only in the forward direction
 	// or in the reverse direction. We do both because it is commonly observed
@@ -389,6 +392,7 @@
 func (p *point) add(dx, dy int) { p.X += dx; p.Y += dy }
 
 // zigzag maps a consecutive sequence of integers to a zig-zag sequence.
+//
 //	[0 1 2 3 4 5 ...] => [0 -1 +1 -2 +2 ...]
 func zigzag(x int) int {
 	if x&1 != 0 {
diff --git a/cmp/options.go b/cmp/options.go
index e57b9eb..e254ffd 100644
--- a/cmp/options.go
+++ b/cmp/options.go
@@ -33,6 +33,7 @@
 }
 
 // applicableOption represents the following types:
+//
 //	Fundamental: ignore | validator | *comparer | *transformer
 //	Grouping:    Options
 type applicableOption interface {
@@ -43,6 +44,7 @@
 }
 
 // coreOption represents the following types:
+//
 //	Fundamental: ignore | validator | *comparer | *transformer
 //	Filters:     *pathFilter | *valuesFilter
 type coreOption interface {
@@ -336,9 +338,9 @@
 // both implement T.
 //
 // The equality function must be:
-//	• Symmetric: equal(x, y) == equal(y, x)
-//	• Deterministic: equal(x, y) == equal(x, y)
-//	• Pure: equal(x, y) does not modify x or y
+//   - Symmetric: equal(x, y) == equal(y, x)
+//   - Deterministic: equal(x, y) == equal(x, y)
+//   - Pure: equal(x, y) does not modify x or y
 func Comparer(f interface{}) Option {
 	v := reflect.ValueOf(f)
 	if !function.IsType(v.Type(), function.Equal) || v.IsNil() {
diff --git a/cmp/path.go b/cmp/path.go
index c710034..557c7f2 100644
--- a/cmp/path.go
+++ b/cmp/path.go
@@ -41,13 +41,13 @@
 	// The type of each valid value is guaranteed to be identical to Type.
 	//
 	// In some cases, one or both may be invalid or have restrictions:
-	//	• For StructField, both are not interface-able if the current field
-	//	is unexported and the struct type is not explicitly permitted by
-	//	an Exporter to traverse unexported fields.
-	//	• For SliceIndex, one may be invalid if an element is missing from
-	//	either the x or y slice.
-	//	• For MapIndex, one may be invalid if an entry is missing from
-	//	either the x or y map.
+	//   - For StructField, both are not interface-able if the current field
+	//     is unexported and the struct type is not explicitly permitted by
+	//     an Exporter to traverse unexported fields.
+	//   - For SliceIndex, one may be invalid if an element is missing from
+	//     either the x or y slice.
+	//   - For MapIndex, one may be invalid if an entry is missing from
+	//     either the x or y map.
 	//
 	// The provided values must not be mutated.
 	Values() (vx, vy reflect.Value)
@@ -94,6 +94,7 @@
 // The simplified path only contains struct field accesses.
 //
 // For example:
+//
 //	MyMap.MySlices.MyField
 func (pa Path) String() string {
 	var ss []string
@@ -108,6 +109,7 @@
 // GoString returns the path to a specific node using Go syntax.
 //
 // For example:
+//
 //	(*root.MyMap["key"].(*mypkg.MyStruct).MySlices)[2][3].MyField
 func (pa Path) GoString() string {
 	var ssPre, ssPost []string
diff --git a/cmp/report_slices.go b/cmp/report_slices.go
index 68b5c1a..21aecd9 100644
--- a/cmp/report_slices.go
+++ b/cmp/report_slices.go
@@ -171,12 +171,13 @@
 		// differences in a string literal. This format is more readable,
 		// but has edge-cases where differences are visually indistinguishable.
 		// This format is avoided under the following conditions:
-		//	• A line starts with `"""`
-		//	• A line starts with "..."
-		//	• A line contains non-printable characters
-		//	• Adjacent different lines differ only by whitespace
+		//   - A line starts with `"""`
+		//   - A line starts with "..."
+		//   - A line contains non-printable characters
+		//   - Adjacent different lines differ only by whitespace
 		//
 		// For example:
+		//
 		//		"""
 		//		... // 3 identical lines
 		//		foo
@@ -446,7 +447,6 @@
 //		{NumIdentical: 3},
 //		{NumInserted: 1},
 //	]
-//
 func coalesceAdjacentEdits(name string, es diff.EditScript) (groups []diffStats) {
 	var prevMode byte
 	lastStats := func(mode byte) *diffStats {
@@ -503,7 +503,6 @@
 //		{NumIdentical: 8, NumRemoved: 12, NumInserted: 3},
 //		{NumIdentical: 63},
 //	]
-//
 func coalesceInterveningIdentical(groups []diffStats, windowSize int) []diffStats {
 	groups, groupsOrig := groups[:0], groups
 	for i, ds := range groupsOrig {
@@ -548,7 +547,6 @@
 //		{NumRemoved: 9},
 //		{NumIdentical: 64}, // incremented by 10
 //	]
-//
 func cleanupSurroundingIdentical(groups []diffStats, eq func(i, j int) bool) []diffStats {
 	var ix, iy int // indexes into sequence x and y
 	for i, ds := range groups {
diff --git a/cmp/report_text.go b/cmp/report_text.go
index 0fd46d7..388fcf5 100644
--- a/cmp/report_text.go
+++ b/cmp/report_text.go
@@ -393,6 +393,7 @@
 // String prints a humanly-readable summary of coalesced records.
 //
 // Example:
+//
 //	diffStats{Name: "Field", NumIgnored: 5}.String() => "5 ignored fields"
 func (s diffStats) String() string {
 	var ss []string