Fix some false positives, add configuration, fix linter errors

* Functions on one line should not be considered
* Fix better token.Pos() for whitespaces
* Fix variable names
* Add stringer
* Support configuration (not yet exposed properly)
* Support to whitelist any RHS
* Support to whitelist any calls one line above
* Support to cuddle any assignment and call if any of the RHS/LHS is
used

Author: bombsimon

README.md

@@ -14,6 +14,13 @@ good, making it harder for other people to read and understand. The linter will
 warn about newlines in and around blocks, in the beginning of files and other
 places in the code.
 
+**I know this linter is aggressive** and a lot of projects I've tested it on
+have failed miserably. For this linter to be useful at all I want to be open to
+new ideas, configurations and discussions! Also note that some of the warnings
+might be bugs or unintentional false positives so I would love an
+[issue](https://github.com/bombsimon/wsl/issues/new) to fix, discuss, change or
+make something configurable!
+
 ## Usage
 
 Install by using `go get -u github.com/bombsimon/wsl/cmd/...`.
@@ -26,6 +33,9 @@ By default, the linter will run on `./...` which means all go files in the
 current path and all subsequent paths, including test files. To disable linting
 test files, use `-n` or `--no-test`.
 
+This linter can also be used as a part of
+[golangci-lint](https://github.com/golangci/golangci-lint)
+
 ## Rules
 
 Note that this linter doesn't take in consideration the issues that will be
@@ -335,6 +345,11 @@ fmt.Println(a)
 
 foo := true
 someFunc(false)
+
+if someBool() {
+    fmt.Println("doing things")
+}
+x.Calling()
 ```
 
 **Do**
@@ -350,6 +365,12 @@ someFunc(foo)
 bar := false
 
 someFunc(true)
+
+if someBool() {
+    fmt.Println("doing things")
+}
+
+x.Calling()
 ```
 
 #### Ranges

cmd/wsl/main.go

@@ -12,27 +12,26 @@ import (
 
 func main() {
 	var (
-		args       []string
-		help       bool
-		notest     bool
-		warnings   bool
-		cwd, _     = os.Getwd()
-		files      = []string{}
-		finalFiles = []string{}
+		args         []string
+		help         bool
+		noTest       bool
+		showWarnings bool
+		cwd, _       = os.Getwd()
+		files        = []string{}
+		finalFiles   = []string{}
 	)
 
 	flag.BoolVar(&help, "h", false, "Show this help text")
 	flag.BoolVar(&help, "help", false, "")
-	flag.BoolVar(&notest, "n", false, "Don't lint test files")
-	flag.BoolVar(&notest, "no-test", false, "")
-	flag.BoolVar(&warnings, "w", false, "Show warnings (ignored rules)")
-	flag.BoolVar(&warnings, "warnings", false, "")
+	flag.BoolVar(&noTest, "n", false, "Don't lint test files")
+	flag.BoolVar(&noTest, "no-test", false, "")
+	flag.BoolVar(&showWarnings, "w", false, "Show warnings (ignored rules)")
+	flag.BoolVar(&showWarnings, "warnings", false, "")
 
 	flag.Parse()
 
 	if help {
 		showHelp()
-
 		return
 	}
 
@@ -57,7 +56,7 @@ func main() {
 
 	// Use relative path to print shorter names, sort out test files if chosen.
 	for _, f := range files {
-		if notest {
+		if noTest {
 			if strings.HasSuffix(f, "_test.go") {
 				continue
 			}
@@ -72,26 +71,25 @@ func main() {
 		finalFiles = append(finalFiles, f)
 	}
 
-	r, w := wsl.ProcessFiles(finalFiles)
+	processor := wsl.NewProcessor()
+	result, warnings := processor.ProcessFiles(finalFiles)
 
-	for _, x := range r {
-		fmt.Printf("%s:%d: %s\n", x.FileName, x.LineNumber, x.Reason)
+	for _, r := range result {
+		fmt.Println(r.String())
 	}
 
-	if warnings && len(w) > 0 {
+	if showWarnings && len(warnings) > 0 {
 		fmt.Println()
 		fmt.Println("⚠️  Warnings found")
 
-		for _, x := range w {
-			fmt.Println(x)
+		for _, w := range warnings {
+			fmt.Println(w)
 		}
 	}
 
-	if len(r) > 0 {
+	if len(result) > 0 {
 		os.Exit(2)
 	}
-
-	return
 }
 
 func expandGoWildcard(root string) []string {

go.mod

@@ -1,7 +1,7 @@
 module github.com/bombsimon/wsl
 
 require (
-	github.com/davecgh/go-spew v1.1.1
+	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/kr/pretty v0.1.0 // indirect
 	github.com/stretchr/testify v1.4.0
 	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect

go.sum

@@ -18,7 +18,5 @@ gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogR
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
-gopkg.in/yaml.v2 v2.2.3 h1:fvjTMHxHEw/mxHbtzPi3JCcKXQRAnQTBRo6YCJSVHKI=
-gopkg.in/yaml.v2 v2.2.3/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.4 h1:/eiJrUcujPVeJ3xlSWaiNi3uSVmDGBK1pDHUHAnao1I=
 gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=