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2528 lines (2169 loc) 路 59.4 KB
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package lo
import (
"errors"
"math"
"math/rand"
"testing"
"time"
"github.com/stretchr/testify/assert"
)
func TestIndexOf(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []int
element int
expected int
}{
{name: "element present", collection: []int{0, 1, 2, 1, 2, 3}, element: 2, expected: 2},
{name: "element absent", collection: []int{0, 1, 2, 1, 2, 3}, element: 6, expected: -1},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
is.Equal(tt.expected, IndexOf(tt.collection, tt.element))
})
}
}
func TestLastIndexOf(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []int
element int
expected int
}{
{name: "element present", collection: []int{0, 1, 2, 1, 2, 3}, element: 2, expected: 4},
{name: "element absent", collection: []int{0, 1, 2, 1, 2, 3}, element: 6, expected: -1},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
is.Equal(tt.expected, LastIndexOf(tt.collection, tt.element))
})
}
}
func TestHasPrefix(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []int
prefix []int
expected bool
}{
{name: "matching prefix", collection: []int{1, 2, 3, 4}, prefix: []int{1, 2}, expected: true},
{name: "non-matching prefix", collection: []int{1, 2, 3, 4}, prefix: []int{42}, expected: false},
{name: "nil prefix", collection: []int{1, 2, 3, 4}, prefix: nil, expected: true},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
is.Equal(tt.expected, HasPrefix(tt.collection, tt.prefix))
})
}
}
func TestHasSuffix(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []int
suffix []int
expected bool
}{
{name: "matching suffix", collection: []int{1, 2, 3, 4}, suffix: []int{3, 4}, expected: true},
{name: "non-matching suffix", collection: []int{1, 2, 3, 4}, suffix: []int{42}, expected: false},
{name: "nil suffix", collection: []int{1, 2, 3, 4}, suffix: nil, expected: true},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
is.Equal(tt.expected, HasSuffix(tt.collection, tt.suffix))
})
}
}
func TestFind(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []string
wantSequence []string // items expected to be passed to the predicate, in order
wantResult string
wantOk bool
}{
{
name: "found in middle",
collection: []string{"a", "b", "c", "d"},
wantSequence: []string{"a", "b"},
wantResult: "b",
wantOk: true,
},
{
name: "not found",
collection: []string{"foobar"},
wantSequence: []string{"foobar"},
wantResult: "",
wantOk: false,
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
index := 0
result, ok := Find(tt.collection, func(item string) bool {
is.Equal(tt.wantSequence[index], item)
index++
return item == "b"
})
is.Equal(tt.wantOk, ok)
is.Equal(tt.wantResult, result)
})
}
}
func TestFindErr(t *testing.T) {
t.Parallel()
testErr := assert.AnError
// Test normal operation (no error) - table driven
tests := []struct {
name string
input []string
expected string
}{
{
name: "finds matching element",
input: []string{"a", "b", "c", "d"},
expected: "b",
},
{
name: "element not found",
input: []string{"foobar"},
expected: "",
},
{
name: "empty collection",
input: []string{},
expected: "",
},
{
name: "single element found",
input: []string{"b"},
expected: "b",
},
{
name: "single element not found",
input: []string{"a"},
expected: "",
},
{
name: "finds first match",
input: []string{"a", "b", "c", "b"},
expected: "b", // first "b"
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
result, err := FindErr(tt.input, func(item string) (bool, error) {
return item == "b", nil
})
is.NoError(err)
is.Equal(tt.expected, result)
})
}
// Test error cases - table driven with callback count verification
errorTests := []struct {
name string
input []string
errorAt string
expectedCalls int
}{
{
name: "error at first element",
input: []string{"b", "c", "d"},
errorAt: "b",
expectedCalls: 1,
},
{
name: "error at second element",
input: []string{"a", "b", "c"},
errorAt: "b",
expectedCalls: 2,
},
{
name: "error at third element",
input: []string{"a", "c", "b"},
errorAt: "b",
expectedCalls: 3,
},
}
for _, tt := range errorTests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
callbackCount := 0
result, err := FindErr(tt.input, func(item string) (bool, error) {
callbackCount++
if item == tt.errorAt {
return false, testErr
}
return item == "b", nil
})
is.ErrorIs(err, testErr)
is.Equal(tt.expectedCalls, callbackCount, "callback count mismatch - iteration didn't stop early")
is.Empty(result, "zero value should be returned on error")
})
}
}
func TestFindIndexOf(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []string
wantSequence []string // items expected to be passed to the predicate, in order
wantItem string
wantIndex int
wantOk bool
}{
{
name: "found in middle",
collection: []string{"a", "b", "c", "d", "b"},
wantSequence: []string{"a", "b"},
wantItem: "b",
wantIndex: 1,
wantOk: true,
},
{
name: "not found",
collection: []string{"foobar"},
wantSequence: []string{"foobar"},
wantItem: "",
wantIndex: -1,
wantOk: false,
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
index := 0
item, itemIndex, ok := FindIndexOf(tt.collection, func(item string) bool {
is.Equal(tt.wantSequence[index], item)
index++
return item == "b"
})
is.Equal(tt.wantItem, item)
is.Equal(tt.wantOk, ok)
is.Equal(tt.wantIndex, itemIndex)
})
}
}
func TestFindLastIndexOf(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []string
wantSequence []string // items expected to be passed to the predicate, in reverse order
wantItem string
wantIndex int
wantOk bool
}{
{
name: "found scanning from the end",
collection: []string{"a", "b", "c", "d", "b"},
wantSequence: []string{"b", "d", "c", "b", "a"},
wantItem: "b",
wantIndex: 4,
wantOk: true,
},
{
name: "not found",
collection: []string{"foobar"},
wantSequence: []string{"foobar"},
wantItem: "",
wantIndex: -1,
wantOk: false,
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
index := 0
item, itemIndex, ok := FindLastIndexOf(tt.collection, func(item string) bool {
is.Equal(tt.wantSequence[index], item)
index++
return item == "b"
})
is.Equal(tt.wantItem, item)
is.Equal(tt.wantOk, ok)
is.Equal(tt.wantIndex, itemIndex)
})
}
}
func TestFindOrElse(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []string
fallback string
wantSequence []string // items expected to be passed to the predicate, in order
expected string
}{
{
name: "found in middle",
collection: []string{"a", "b", "c", "d"},
fallback: "x",
wantSequence: []string{"a", "b"},
expected: "b",
},
{
name: "not found falls back",
collection: []string{"foobar"},
fallback: "x",
wantSequence: []string{"foobar"},
expected: "x",
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
index := 0
result := FindOrElse(tt.collection, tt.fallback, func(item string) bool {
is.Equal(tt.wantSequence[index], item)
index++
return item == "b"
})
is.Equal(tt.expected, result)
})
}
}
func TestFindKey(t *testing.T) {
t.Parallel()
t.Run("int values", func(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection map[string]int
value int
wantKey string
wantOk bool
}{
{name: "value present", collection: map[string]int{"foo": 1, "bar": 2, "baz": 3}, value: 2, wantKey: "bar", wantOk: true},
{name: "value absent", collection: map[string]int{"foo": 1, "bar": 2, "baz": 3}, value: 42, wantKey: "", wantOk: false},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
result, ok := FindKey(tt.collection, tt.value)
is.Equal(tt.wantKey, result)
is.Equal(tt.wantOk, ok)
})
}
})
t.Run("struct values", func(t *testing.T) {
t.Parallel()
type test struct {
foobar string
}
tests := []struct {
name string
collection map[string]test
value test
wantKey string
wantOk bool
}{
{name: "value present", collection: map[string]test{"foo": {"foo"}, "bar": {"bar"}, "baz": {"baz"}}, value: test{"foo"}, wantKey: "foo", wantOk: true},
{name: "value absent", collection: map[string]test{"foo": {"foo"}, "bar": {"bar"}, "baz": {"baz"}}, value: test{"hello world"}, wantKey: "", wantOk: false},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
result, ok := FindKey(tt.collection, tt.value)
is.Equal(tt.wantKey, result)
is.Equal(tt.wantOk, ok)
})
}
})
}
func TestFindKeyBy(t *testing.T) {
t.Parallel()
tests := []struct {
name string
predicate func(k string, v int) bool
wantKey string
wantOk bool
}{
{
name: "predicate matches",
predicate: func(k string, v int) bool { return k == "foo" },
wantKey: "foo",
wantOk: true,
},
{
name: "predicate matches nothing",
predicate: func(k string, v int) bool { return false },
wantKey: "",
wantOk: false,
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
result, ok := FindKeyBy(map[string]int{"foo": 1, "bar": 2, "baz": 3}, tt.predicate)
is.Equal(tt.wantKey, result)
is.Equal(tt.wantOk, ok)
})
}
}
// TestFindUniques_smallScan exercises the small-scan path (all collections
// here are <= findSmallThreshold). See TestFindUniques_large for the
// map-based path.
func TestFindUniques_smallScan(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []int
expected []int
}{
{name: "all unique", collection: []int{1, 2, 3}, expected: []int{1, 2, 3}},
{name: "one unique among duplicates", collection: []int{1, 2, 2, 3, 1, 2}, expected: []int{3}},
{name: "no unique", collection: []int{1, 2, 2, 1}, expected: nil},
{name: "empty collection", collection: []int{}, expected: nil},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
result := FindUniques(tt.collection)
if tt.expected == nil {
is.Empty(result)
} else {
is.Equal(tt.expected, result)
}
})
}
t.Run("type preserved", func(t *testing.T) {
t.Parallel()
is := assert.New(t)
type myStrings []string
allStrings := myStrings{"", "foo", "bar"}
nonempty := FindUniques(allStrings)
is.IsType(nonempty, allStrings, "type preserved")
})
}
// FindUniques dispatches on len(collection) <= findSmallThreshold (8): a
// collection of 12 elements forces the findUniquesLarge path, which the
// table above never exercises (its collections are all <= 6 elements).
func TestFindUniques_large(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []int
expected []int
}{
{
name: "some unique",
collection: []int{10, 20, 30, 20, 40, 50, 60, 70, 80, 90, 40, 10},
expected: []int{30, 50, 60, 70, 80, 90},
},
{
name: "no unique",
collection: []int{1, 1, 2, 2, 3, 3, 4, 4, 5, 5},
expected: nil,
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
is.Greater(len(tt.collection), findSmallThreshold, "sanity check: collection must exceed findSmallThreshold")
result := FindUniques(tt.collection)
if tt.expected == nil {
is.Empty(result)
} else {
is.Equal(tt.expected, result)
}
})
}
t.Run("type preserved", func(t *testing.T) {
t.Parallel()
is := assert.New(t)
type myInts []int
allUnique := myInts{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
is.Greater(len(allUnique), findSmallThreshold, "sanity check: allUnique must exceed findSmallThreshold")
nonempty := FindUniques(allUnique)
is.Equal(myInts{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, nonempty)
is.IsType(nonempty, allUnique, "type preserved")
})
}
// TestFindUniquesBy_smallScan exercises the small-scan path (all collections
// here are <= findSmallThreshold). See TestFindUniquesBy_large for the
// map-based path.
func TestFindUniquesBy_smallScan(t *testing.T) {
t.Parallel()
mod3 := func(i int) int { return i % 3 }
tests := []struct {
name string
collection []int
expected []int
}{
{name: "all unique", collection: []int{0, 1, 2}, expected: []int{0, 1, 2}},
{name: "one unique among duplicates", collection: []int{0, 1, 2, 3, 4}, expected: []int{2}},
{name: "no unique", collection: []int{0, 1, 2, 3, 4, 5}, expected: nil},
{name: "empty collection", collection: []int{}, expected: nil},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
result := FindUniquesBy(tt.collection, mod3)
if tt.expected == nil {
is.Empty(result)
} else {
is.Equal(tt.expected, result)
}
})
}
t.Run("type preserved", func(t *testing.T) {
t.Parallel()
is := assert.New(t)
type myStrings []string
allStrings := myStrings{"", "foo", "bar"}
nonempty := FindUniquesBy(allStrings, func(i string) string {
return i
})
is.IsType(nonempty, allStrings, "type preserved")
})
}
// FindUniquesBy dispatches on len(collection) <= findSmallThreshold (8): a
// collection of 12 elements forces the findUniquesByLarge path, which the
// table above never exercises (its collections are all <= 6 elements).
func TestFindUniquesBy_large(t *testing.T) {
t.Parallel()
byTen := func(v int) int { return v / 10 }
tests := []struct {
name string
collection []int
expected []int
}{
{
name: "some unique",
collection: []int{10, 20, 30, 20, 40, 50, 60, 70, 80, 90, 40, 10},
expected: []int{30, 50, 60, 70, 80, 90},
},
{
name: "no unique",
collection: []int{10, 11, 20, 21, 30, 31, 40, 41, 50, 51},
expected: nil,
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
is.Greater(len(tt.collection), findSmallThreshold, "sanity check: collection must exceed findSmallThreshold")
result := FindUniquesBy(tt.collection, byTen)
if tt.expected == nil {
is.Empty(result)
} else {
is.Equal(tt.expected, result)
}
})
}
t.Run("type preserved", func(t *testing.T) {
t.Parallel()
is := assert.New(t)
type myStrings []string
allStrings := myStrings{"a", "bb", "ccc", "dddd", "eeeee", "ffffff", "ggggggg", "hhhhhhhh", "iiiiiiiii"}
is.Greater(len(allStrings), findSmallThreshold, "sanity check: allStrings must exceed findSmallThreshold")
nonempty := FindUniquesBy(allStrings, func(s string) int { return len(s) })
is.IsType(nonempty, allStrings, "type preserved")
})
}
// TestFindDuplicates_smallScan exercises the small-scan path (all
// collections here are <= findSmallThreshold). See
// TestFindDuplicates_large for the map-based path.
func TestFindDuplicates_smallScan(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []int
expected []int
}{
{name: "some duplicates", collection: []int{1, 2, 2, 1, 2, 3}, expected: []int{1, 2}},
{name: "no duplicates", collection: []int{1, 2, 3}, expected: nil},
{name: "empty collection", collection: []int{}, expected: nil},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
result := FindDuplicates(tt.collection)
if tt.expected == nil {
is.Empty(result)
} else {
is.Equal(tt.expected, result)
}
})
}
t.Run("type preserved", func(t *testing.T) {
t.Parallel()
is := assert.New(t)
type myStrings []string
allStrings := myStrings{"", "foo", "bar"}
nonempty := FindDuplicates(allStrings)
is.IsType(nonempty, allStrings, "type preserved")
})
}
// FindDuplicates dispatches on len(collection) <= findSmallThreshold (8): a
// collection of 12 elements forces the findDuplicatesLarge path, which the
// table above never exercises (its collections are all <= 6 elements).
func TestFindDuplicates_large(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []int
expected []int
}{
{
name: "some duplicates",
collection: []int{10, 20, 30, 20, 40, 50, 60, 70, 80, 90, 40, 10},
expected: []int{10, 20, 40},
},
{
name: "no duplicates",
collection: []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10},
expected: nil,
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
is.Greater(len(tt.collection), findSmallThreshold, "sanity check: collection must exceed findSmallThreshold")
result := FindDuplicates(tt.collection)
if tt.expected == nil {
is.Empty(result)
} else {
is.Equal(tt.expected, result)
}
})
}
t.Run("type preserved", func(t *testing.T) {
t.Parallel()
is := assert.New(t)
type myStrings []string
allStrings := myStrings{"a", "b", "c", "d", "e", "f", "g", "h", "i"}
is.Greater(len(allStrings), findSmallThreshold, "sanity check: allStrings must exceed findSmallThreshold")
nonempty := FindDuplicates(allStrings)
is.IsType(nonempty, allStrings, "type preserved")
})
}
// TestFindDuplicatesBy_smallScan exercises the small-scan path (all
// collections here are <= findSmallThreshold). See
// TestFindDuplicatesBy_large for the map-based path.
func TestFindDuplicatesBy_smallScan(t *testing.T) {
t.Parallel()
tests := []struct {
name string
collection []int
by func(i int) int
expected []int
}{
{name: "some duplicates", collection: []int{3, 4, 5, 6, 7}, by: func(i int) int { return i % 3 }, expected: []int{3, 4}},
{name: "no duplicates", collection: []int{0, 1, 2, 3, 4}, by: func(i int) int { return i % 5 }, expected: nil},
{name: "empty collection", collection: []int{}, by: func(i int) int { return i % 3 }, expected: nil},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
result := FindDuplicatesBy(tt.collection, tt.by)
if tt.expected == nil {
is.Empty(result)
} else {
is.Equal(tt.expected, result)
}
})
}
t.Run("type preserved", func(t *testing.T) {
t.Parallel()
is := assert.New(t)
type myStrings []string
allStrings := myStrings{"", "foo", "bar"}
nonempty := FindDuplicatesBy(allStrings, func(i string) string {
return i
})
is.IsType(nonempty, allStrings, "type preserved")
})
}
// FindDuplicatesBy dispatches on len(collection) <= findSmallThreshold (8): a
// collection of 12 elements forces the findDuplicatesByLarge path, which the
// table above never exercises (its collections are all <= 5 elements).
func TestFindDuplicatesBy_large(t *testing.T) {
t.Parallel()
byTen := func(v int) int { return v / 10 }
tests := []struct {
name string
collection []int
expected []int
}{
{
name: "some duplicates",
collection: []int{10, 20, 30, 20, 40, 50, 60, 70, 80, 90, 40, 10},
expected: []int{10, 20, 40},
},
{
name: "no duplicates",
collection: []int{10, 21, 32, 43, 54, 65, 76, 87, 98, 109},
expected: nil,
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
is.Greater(len(tt.collection), findSmallThreshold, "sanity check: collection must exceed findSmallThreshold")
result := FindDuplicatesBy(tt.collection, byTen)
if tt.expected == nil {
is.Empty(result)
} else {
is.Equal(tt.expected, result)
}
})
}
t.Run("type preserved", func(t *testing.T) {
t.Parallel()
is := assert.New(t)
type myStrings []string
allStrings := myStrings{"a", "bb", "ccc", "dddd", "eeeee", "ffffff", "ggggggg", "hhhhhhhh", "iiiiiiiii"}
is.Greater(len(allStrings), findSmallThreshold, "sanity check: allStrings must exceed findSmallThreshold")
nonempty := FindDuplicatesBy(allStrings, func(s string) int { return len(s) })
is.IsType(nonempty, allStrings, "type preserved")
})
}
func TestFindDuplicatesByErr(t *testing.T) {
t.Parallel()
is := assert.New(t)
// Table-driven tests for normal operation
tests := []struct {
name string
input []int
expected []int
}{
{
name: "finds duplicates by key",
input: []int{3, 4, 5, 6, 7},
expected: []int{3, 4},
},
{
name: "no duplicates",
input: []int{0, 1, 2, 3, 4},
expected: []int{0, 1},
},
{
name: "empty collection",
input: []int{},
expected: []int{},
},
{
name: "all duplicates",
input: []int{0, 3, 6, 9},
expected: []int{0},
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
result, err := FindDuplicatesByErr(tt.input, func(i int) (int, error) {
return i % 3, nil
})
is.NoError(err)
is.Equal(tt.expected, result)
})
}
// Table-driven tests with callback count verification for early return
testErr := errors.New("test error")
errorTests := []struct {
name string
input []int
errorAt int
expectedCalls int
}{
{
name: "error in first pass at element 0",
input: []int{3, 4, 5},
errorAt: 0,
expectedCalls: 1,
},
{
name: "error in first pass at element 2",
input: []int{3, 4, 5},
errorAt: 2,
expectedCalls: 3,
},
{
name: "error in second pass at first duplicate",
input: []int{3, 4, 5, 6},
errorAt: 3,
expectedCalls: 4, // First pass completes (4 items), error at first item of second pass
},
}
for _, tt := range errorTests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
is := assert.New(t)
callbackCount := 0
result, err := FindDuplicatesByErr(tt.input, func(i int) (int, error) {
callbackCount++
if i == tt.input[tt.errorAt] {
return 0, testErr
}
return i % 3, nil
})
is.ErrorIs(err, testErr)
is.Equal(tt.expectedCalls, callbackCount, "callback count mismatch - iteration didn't stop early")
is.Nil(result, "nil should be returned on error")
})
}
// Test type preservation
type myStrings []string
allStrings := myStrings{"a", "b", "a", "c", "b"}
result, err := FindDuplicatesByErr(allStrings, func(s string) (string, error) {
return s, nil
})
is.NoError(err)
is.IsType(result, allStrings, "type preserved")
}
func TestMin(t *testing.T) {
t.Parallel()
tests := []struct {
name string