mirror of
https://github.com/VictoriaMetrics/VictoriaMetrics.git
synced 2024-12-25 03:40:10 +01:00
486 lines
9.9 KiB
Go
486 lines
9.9 KiB
Go
package simple
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import "honnef.co/go/tools/lint"
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var Docs = map[string]*lint.Documentation{
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"S1000": {
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Title: `Use plain channel send or receive instead of single-case select`,
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Text: `Select statements with a single case can be replaced with a simple
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send or receive.
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Before:
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select {
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case x := <-ch:
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fmt.Println(x)
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}
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After:
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x := <-ch
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fmt.Println(x)`,
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Since: "2017.1",
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},
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"S1001": {
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Title: `Replace for loop with call to copy`,
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Text: `Use copy() for copying elements from one slice to another.
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Before:
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for i, x := range src {
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dst[i] = x
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}
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After:
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copy(dst, src)`,
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Since: "2017.1",
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},
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"S1002": {
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Title: `Omit comparison with boolean constant`,
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Text: `Before:
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if x == true {}
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After:
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if x {}`,
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Since: "2017.1",
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},
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"S1003": {
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Title: `Replace call to strings.Index with strings.Contains`,
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Text: `Before:
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if strings.Index(x, y) != -1 {}
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After:
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if strings.Contains(x, y) {}`,
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Since: "2017.1",
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},
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"S1004": {
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Title: `Replace call to bytes.Compare with bytes.Equal`,
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Text: `Before:
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if bytes.Compare(x, y) == 0 {}
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After:
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if bytes.Equal(x, y) {}`,
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Since: "2017.1",
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},
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"S1005": {
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Title: `Drop unnecessary use of the blank identifier`,
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Text: `In many cases, assigning to the blank identifier is unnecessary.
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Before:
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for _ = range s {}
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x, _ = someMap[key]
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_ = <-ch
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After:
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for range s{}
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x = someMap[key]
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<-ch`,
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Since: "2017.1",
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},
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"S1006": {
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Title: `Use for { ... } for infinite loops`,
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Text: `For infinite loops, using for { ... } is the most idiomatic choice.`,
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Since: "2017.1",
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},
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"S1007": {
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Title: `Simplify regular expression by using raw string literal`,
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Text: `Raw string literals use ` + "`" + ` instead of " and do not support
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any escape sequences. This means that the backslash (\) can be used
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freely, without the need of escaping.
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Since regular expressions have their own escape sequences, raw strings
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can improve their readability.
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Before:
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regexp.Compile("\\A(\\w+) profile: total \\d+\\n\\z")
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After:
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regexp.Compile(` + "`" + `\A(\w+) profile: total \d+\n\z` + "`" + `)`,
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Since: "2017.1",
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},
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"S1008": {
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Title: `Simplify returning boolean expression`,
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Text: `Before:
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if <expr> {
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return true
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}
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return false
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After:
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return <expr>`,
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Since: "2017.1",
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},
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"S1009": {
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Title: `Omit redundant nil check on slices`,
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Text: `The len function is defined for all slices, even nil ones, which have
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a length of zero. It is not necessary to check if a slice is not nil
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before checking that its length is not zero.
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Before:
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if x != nil && len(x) != 0 {}
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After:
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if len(x) != 0 {}`,
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Since: "2017.1",
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},
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"S1010": {
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Title: `Omit default slice index`,
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Text: `When slicing, the second index defaults to the length of the value,
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making s[n:len(s)] and s[n:] equivalent.`,
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Since: "2017.1",
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},
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"S1011": {
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Title: `Use a single append to concatenate two slices`,
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Text: `Before:
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for _, e := range y {
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x = append(x, e)
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}
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After:
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x = append(x, y...)`,
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Since: "2017.1",
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},
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"S1012": {
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Title: `Replace time.Now().Sub(x) with time.Since(x)`,
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Text: `The time.Since helper has the same effect as using time.Now().Sub(x)
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but is easier to read.
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Before:
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time.Now().Sub(x)
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After:
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time.Since(x)`,
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Since: "2017.1",
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},
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"S1016": {
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Title: `Use a type conversion instead of manually copying struct fields`,
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Text: `Two struct types with identical fields can be converted between each
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other. In older versions of Go, the fields had to have identical
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struct tags. Since Go 1.8, however, struct tags are ignored during
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conversions. It is thus not necessary to manually copy every field
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individually.
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Before:
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var x T1
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y := T2{
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Field1: x.Field1,
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Field2: x.Field2,
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}
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After:
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var x T1
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y := T2(x)`,
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Since: "2017.1",
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},
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"S1017": {
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Title: `Replace manual trimming with strings.TrimPrefix`,
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Text: `Instead of using strings.HasPrefix and manual slicing, use the
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strings.TrimPrefix function. If the string doesn't start with the
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prefix, the original string will be returned. Using strings.TrimPrefix
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reduces complexity, and avoids common bugs, such as off-by-one
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mistakes.
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Before:
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if strings.HasPrefix(str, prefix) {
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str = str[len(prefix):]
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}
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After:
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str = strings.TrimPrefix(str, prefix)`,
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Since: "2017.1",
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},
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"S1018": {
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Title: `Use copy for sliding elements`,
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Text: `copy() permits using the same source and destination slice, even with
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overlapping ranges. This makes it ideal for sliding elements in a
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slice.
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Before:
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for i := 0; i < n; i++ {
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bs[i] = bs[offset+i]
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}
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After:
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copy(bs[:n], bs[offset:])`,
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Since: "2017.1",
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},
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"S1019": {
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Title: `Simplify make call by omitting redundant arguments`,
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Text: `The make function has default values for the length and capacity
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arguments. For channels and maps, the length defaults to zero.
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Additionally, for slices the capacity defaults to the length.`,
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Since: "2017.1",
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},
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"S1020": {
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Title: `Omit redundant nil check in type assertion`,
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Text: `Before:
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if _, ok := i.(T); ok && i != nil {}
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After:
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if _, ok := i.(T); ok {}`,
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Since: "2017.1",
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},
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"S1021": {
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Title: `Merge variable declaration and assignment`,
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Text: `Before:
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var x uint
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x = 1
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After:
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var x uint = 1`,
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Since: "2017.1",
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},
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"S1023": {
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Title: `Omit redundant control flow`,
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Text: `Functions that have no return value do not need a return statement as
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the final statement of the function.
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Switches in Go do not have automatic fallthrough, unlike languages
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like C. It is not necessary to have a break statement as the final
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statement in a case block.`,
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Since: "2017.1",
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},
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"S1024": {
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Title: `Replace x.Sub(time.Now()) with time.Until(x)`,
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Text: `The time.Until helper has the same effect as using x.Sub(time.Now())
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but is easier to read.
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Before:
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x.Sub(time.Now())
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After:
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time.Until(x)`,
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Since: "2017.1",
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},
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"S1025": {
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Title: `Don't use fmt.Sprintf("%s", x) unnecessarily`,
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Text: `In many instances, there are easier and more efficient ways of getting
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a value's string representation. Whenever a value's underlying type is
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a string already, or the type has a String method, they should be used
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directly.
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Given the following shared definitions
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type T1 string
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type T2 int
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func (T2) String() string { return "Hello, world" }
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var x string
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var y T1
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var z T2
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we can simplify the following
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fmt.Sprintf("%s", x)
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fmt.Sprintf("%s", y)
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fmt.Sprintf("%s", z)
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to
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x
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string(y)
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z.String()`,
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Since: "2017.1",
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},
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"S1028": {
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Title: `Simplify error construction with fmt.Errorf`,
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Text: `Before:
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errors.New(fmt.Sprintf(...))
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After:
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fmt.Errorf(...)`,
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Since: "2017.1",
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},
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"S1029": {
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Title: `Range over the string directly`,
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Text: `Ranging over a string will yield byte offsets and runes. If the offset
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isn't used, this is functionally equivalent to converting the string
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to a slice of runes and ranging over that. Ranging directly over the
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string will be more performant, however, as it avoids allocating a new
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slice, the size of which depends on the length of the string.
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Before:
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for _, r := range []rune(s) {}
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After:
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for _, r := range s {}`,
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Since: "2017.1",
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},
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"S1030": {
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Title: `Use bytes.Buffer.String or bytes.Buffer.Bytes`,
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Text: `bytes.Buffer has both a String and a Bytes method. It is never
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necessary to use string(buf.Bytes()) or []byte(buf.String()) – simply
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use the other method.`,
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Since: "2017.1",
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},
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"S1031": {
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Title: `Omit redundant nil check around loop`,
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Text: `You can use range on nil slices and maps, the loop will simply never
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execute. This makes an additional nil check around the loop
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unnecessary.
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Before:
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if s != nil {
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for _, x := range s {
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...
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}
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}
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After:
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for _, x := range s {
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...
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}`,
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Since: "2017.1",
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},
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"S1032": {
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Title: `Use sort.Ints(x), sort.Float64s(x), and sort.Strings(x)`,
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Text: `The sort.Ints, sort.Float64s and sort.Strings functions are easier to
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read than sort.Sort(sort.IntSlice(x)), sort.Sort(sort.Float64Slice(x))
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and sort.Sort(sort.StringSlice(x)).
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Before:
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sort.Sort(sort.StringSlice(x))
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After:
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sort.Strings(x)`,
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Since: "2019.1",
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},
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"S1033": {
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Title: `Unnecessary guard around call to delete`,
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Text: `Calling delete on a nil map is a no-op.`,
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Since: "2019.2",
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},
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"S1034": {
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Title: `Use result of type assertion to simplify cases`,
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Since: "2019.2",
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},
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"S1035": {
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Title: `Redundant call to net/http.CanonicalHeaderKey in method call on net/http.Header`,
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Text: `The methods on net/http.Header, namely Add, Del, Get and Set, already
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canonicalize the given header name.`,
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Since: "2020.1",
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},
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"S1036": {
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Title: `Unnecessary guard around map access`,
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Text: `When accessing a map key that doesn't exist yet, one
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receives a zero value. Often, the zero value is a suitable value, for example when using append or doing integer math.
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The following
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if _, ok := m["foo"]; ok {
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m["foo"] = append(m["foo"], "bar")
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} else {
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m["foo"] = []string{"bar"}
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}
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can be simplified to
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m["foo"] = append(m["foo"], "bar")
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and
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if _, ok := m2["k"]; ok {
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m2["k"] += 4
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} else {
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m2["k"] = 4
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}
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can be simplified to
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m["k"] += 4
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`,
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Since: "2020.1",
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},
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"S1037": {
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Title: `Elaborate way of sleeping`,
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Text: `Using a select statement with a single case receiving
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from the result of time.After is a very elaborate way of sleeping that
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can much simpler be expressed with a simple call to time.Sleep.`,
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Since: "2020.1",
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},
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"S1038": {
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Title: "Unnecessarily complex way of printing formatted string",
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Text: `Instead of using fmt.Print(fmt.Sprintf(...)), one can use fmt.Printf(...).`,
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Since: "2020.1",
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},
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"S1039": {
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Title: "Unnecessary use of fmt.Sprint",
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Text: `Calling fmt.Sprint with a single string argument is unnecessary and identical to using the string directly.`,
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Since: "2020.1",
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},
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}
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