Add support to cuddle assignments for a whole block (#163)

* Support to cuddle assignments for a whole block

* Implement PR suggestions

* Update doc/configuration.md

Co-authored-by: Simon Sawert <simon@sawert.se>

---------

Co-authored-by: Simon Sawert <simon@sawert.se>

analyzer.go

@@ -37,6 +37,7 @@ func defaultConfig() *Configuration {
 		AllowCuddleWithRHS:               []string{"Unlock", "RUnlock"},
 		ErrorVariableNames:               []string{"err"},
 		ForceCaseTrailingWhitespaceLimit: 0,
+		AllowCuddleUsedInBlock:           false,
 	}
 }
 
@@ -68,6 +69,7 @@ func (wa *wslAnalyzer) flags() flag.FlagSet {
 	flags.BoolVar(&wa.config.ForceExclusiveShortDeclarations, "force-short-decl-cuddling", false, "Force short declarations to cuddle by themselves")
 	flags.BoolVar(&wa.config.StrictAppend, "strict-append", true, "Strict rules for append")
 	flags.BoolVar(&wa.config.IncludeGenerated, "include-generated", false, "Include generated files")
+	flags.BoolVar(&wa.config.AllowCuddleUsedInBlock, "allow-cuddle-used-in-block", false, "Allow cuddling of variables used in block statements")
 	flags.IntVar(&wa.config.ForceCaseTrailingWhitespaceLimit, "force-case-trailing-whitespace", 0, "Force newlines for case blocks > this number.")
 
 	flags.Var(&multiStringValue{slicePtr: &wa.config.AllowCuddleWithCalls}, "allow-cuddle-with-calls", "Comma separated list of idents that can have cuddles after")

doc/configuration.md

@@ -233,6 +233,109 @@ var (
 )
 ```
 
+### allow-cuddle-used-in-block
+
+Controls if you may cuddle variables used anywhere in the following block.
+
+> Default value: false
+
+Supported when true:
+
+```go
+counter := 0
+if somethingTrue {
+    checker := getAChecker()
+    if !checker {
+        return
+    }
+
+    counter++
+}
+
+var numbers []int
+for i := 0; i < 10; i++ {
+    if 1 == 1 {
+        numbers = append(numbers, i)
+    }
+}
+
+var numbers2 []int
+for {
+    if 1 == 1 {
+        numbers2 = append(numbers2, 1)
+    }
+}
+
+var id string
+switch {
+case int:
+    if true {
+        id = strconv.Itoa(i)
+    }
+case uint32:
+    if true {
+        id = strconv.Itoa(int(i))
+    }
+case string:
+    if true {
+        id = i
+    }
+}
+```
+
+Required when false:
+
+```go
+counter := 0
+
+if somethingTrue {
+    checker := getAChecker()
+    if !checker {
+        return
+    }
+
+    counter++
+}
+
+var numbers []int
+
+for i := 0; i < 10; i++ {
+    if 1 == 1 {
+        numbers = append(numbers, i)
+    }
+}
+
+var numbers2 []int
+
+for {
+    if 1 == 1 {
+        numbers2 = append(numbers2, 1)
+    }
+}
+
+var id string
+
+switch {
+case int:
+    if true {
+        id = strconv.Itoa(i)
+    }
+case uint32:
+    if true {
+        id = strconv.Itoa(int(i))
+    }
+case string:
+    if true {
+        id = i
+    }
+}
+```
+
+**Note**: this means the option _overrides_ the following rules:
+- [Anonymous switch statements should never be cuddled](rules.md#anonymous-switch-statements-should-never-be-cuddled)
+- [For statement without condition should never be cuddled](rules.md#for-statement-without-condition-should-never-be-cuddled)
+
+
 ### [allow-trailing-comment](rules.md#block-should-not-end-with-a-whitespace-or-comment)
 
 Controls if blocks can end with comments. This is not encouraged sine it's

doc/rules.md

@@ -6,6 +6,8 @@ linter and how they should be resolved or configured to handle.
 ## Checklist
 
 ### Anonymous switch statements should never be cuddled
+> Can be configured, see [configuration
+documentation](configuration.md#allow-cuddle-used-in-block)
 
 Anonymous `switch` statements (mindless `switch`) should deserve its needed
 attention that it does not need any assigned variables. Hence, it should not
@@ -398,6 +400,8 @@ run()
 ---
 
 ### For statement without condition should never be cuddled
+> Can be configured, see [configuration
+documentation](configuration.md#allow-cuddle-used-in-block)
 
 `for` loop without conditions (infinity loop) should deserves its own
 attention. Hence, it should not be cuddled with anyone.

testdata/src/default_config/cuddle_used_in_first_line/cuddle_used_in_first_line.go

@@ -0,0 +1,142 @@
+package testpkg
+
+import (
+	"fmt"
+	"strconv"
+)
+
+func ForCuddleAssignmentWholeBlock() {
+	x := 1
+	y := 2
+
+	var numbers []int
+	for i := 0; i < 10; i++ { // want "for statements should only be cuddled with assignments used in the iteration"
+		if x == y {
+			numbers = append(numbers, i)
+		}
+	}
+
+	var numbers2 []int
+	for i := range 10 { // want "ranges should only be cuddled with assignments used in the iteration"
+		if x == y {
+			numbers2 = append(numbers2, i)
+		}
+	}
+
+	var numbers3 []int
+	for { // want "for statement without condition should never be cuddled"
+		if x == y {
+			numbers3 = append(numbers3, i)
+		}
+	}
+
+	environment = make(map[string]string)
+	for _, env := range req.GetConfig().GetEnvs() { // want "ranges should only be cuddled with assignments used in the iteration"
+		switch env.GetKey() {
+		case "user-data":
+			cloudInitUserData = env.GetValue()
+		default:
+			environment[env.GetKey()] = env.GetValue()
+		}
+	}
+}
+
+func IfCuddleAssignmentWholeBlock() {
+	x := 1
+	y := 2
+
+	counter := 0
+	if somethingTrue { // want "if statements should only be cuddled with assignments used in the if statement itself"
+		checker := getAChecker()
+		if !checker {
+			return
+		}
+
+		counter++ // Cuddled variable used in block, but not as first statement
+	}
+
+	var number2 []int
+	if x == y { // want "if statements should only be cuddled with assignments used in the if statement itself"
+		fmt.Println("a")
+	} else {
+		if x > y {
+			number2 = append(number2, i)
+		}
+	}
+
+	var number3 []int
+	if x == y { // want "if statements should only be cuddled with assignments used in the if statement itself"
+		fmt.Println("a")
+	} else if x > y {
+		if x == y {
+			number3 = append(number3, i)
+		}
+	}
+
+	var number4 []int
+	if x == y { // want "if statements should only be cuddled with assignments used in the if statement itself"
+		if x == y {
+			number4 = append(number4, i)
+		}
+	} else if x > y {
+		if x == y {
+			number4 = append(number4, i)
+		}
+	} else {
+		if x > y {
+			number4 = append(number4, i)
+		}
+	}
+}
+
+func SwitchCuddleAssignmentWholeBlock() {
+	var id string
+	var b bool // want "declarations should never be cuddled"
+	switch b { // want "only one cuddle assignment allowed before switch statement"
+	case true:
+		id = "a"
+	case false:
+		id = "b"
+	}
+
+	var b bool
+	var id string // want "declarations should never be cuddled"
+	switch b {    // want "only one cuddle assignment allowed before switch statement"
+	case true:
+		id = "a"
+	case false:
+		id = "b"
+	}
+
+	var id2 string
+	switch i := objectID.(type) { // want "type switch statements should only be cuddled with variables switched"
+	case int:
+		if true {
+			id2 = strconv.Itoa(i)
+		}
+	case uint32:
+		if true {
+			id2 = strconv.Itoa(int(i))
+		}
+	case string:
+		if true {
+			id2 = i
+		}
+	}
+
+	var id3 string
+	switch { // want "anonymous switch statements should never be cuddled"
+	case int:
+		if true {
+			id3 = strconv.Itoa(i)
+		}
+	case uint32:
+		if true {
+			id3 = strconv.Itoa(int(i))
+		}
+	case string:
+		if true {
+			id3 = i
+		}
+	}
+}