WIP: Removal fixer

* Remove newline in end of block
* Remove newline in start of block (and comments...)

This is WIP because we need to preserve the comments so they don't get
deleted when we remove beginning of blocks.

analyzer.go

@@ -2,7 +2,6 @@ package wsl
 
 import (
 	"flag"
-	"go/token"
 
 	"golang.org/x/tools/go/analysis"
 )
@@ -55,40 +54,35 @@ func run(pass *analysis.Pass) (interface{}, error) {
 
 		for _, v := range processor.Result {
 			var (
-				pos       token.Pos
-				end       token.Pos
 				newText   []byte
 				textEdits []analysis.TextEdit
 			)
 
-			//nolint:exhaustive // Not while TODO
 			switch v.Type {
 			case WhitespaceShouldAddBefore:
-				pos = v.FixNode.Pos()
-				end = v.FixNode.Pos()
 				newText = []byte("\n")
 			case WhitespaceShouldAddAfter:
-				pos = v.FixNode.End()
-				end = v.FixNode.End()
 				newText = []byte("\n")
+			case WhitespaceShouldRemoveEnd:
+				newText = []byte("\n}")
+			case WhitespaceShouldRemoveBeginning:
+				newText = []byte("{\n")
 			default:
-				//nolint:gocritic // We need TODOs while iterating...
+				//nolint:gocritic // Not while TODO
 				// TODO
 				continue
 			}
 
-			if !v.NoFix {
-				textEdits = []analysis.TextEdit{
-					{
-						Pos:     pos,
-						End:     end,
-						NewText: newText,
-					},
-				}
+			textEdits = []analysis.TextEdit{
+				{
+					Pos:     v.FixRangeStart,
+					End:     v.FixRangeEnd,
+					NewText: newText,
+				},
 			}
 
 			d := analysis.Diagnostic{
-				Pos:      v.Node.Pos(),
+				Pos:      v.ReportAt,
 				Category: "",
 				Message:  v.Reason,
 				SuggestedFixes: []analysis.SuggestedFix{

go.mod

@@ -4,13 +4,17 @@ go 1.19
 
 require github.com/stretchr/testify v1.8.1
 
+require (
+	golang.org/x/mod v0.8.0 // indirect
+	golang.org/x/sys v0.5.0 // indirect
+)
+
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	golang.org/x/tools v0.0.0-20200403190813-44a64ad78b9b
-	golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 // indirect
+	golang.org/x/tools v0.6.0
 	gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -17,26 +17,13 @@ github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
-github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
-golang.org/x/mod v0.2.0 h1:KU7oHjnv3XNWfa5COkzUifxZmxp1TyI7ImMXqFxLwvQ=
-golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
-golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.0.0-20200403190813-44a64ad78b9b h1:AFZdJUT7jJYXQEC29hYH/WZkoV7+KhwxQGmdZ19yYoY=
-golang.org/x/tools v0.0.0-20200403190813-44a64ad78b9b/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
-golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/mod v0.8.0 h1:LUYupSeNrTNCGzR/hVBk2NHZO4hXcVaW1k4Qx7rjPx8=
+golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
+golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
+golang.org/x/sys v0.5.0 h1:MUK/U/4lj1t1oPg0HfuXDN/Z1wv31ZJ/YcPiGccS4DU=
+golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/tools v0.6.0 h1:BOw41kyTf3PuCW1pVQf8+Cyg8pMlkYB1oo9iJ6D/lKM=
+golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f h1:BLraFXnmrev5lT+xlilqcH8XK9/i0At2xKjWk4p6zsU=
 gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

testdata/fix_advanced.go

@@ -2,7 +2,7 @@ package testpkg
 
 func Advanced() {
 	var foo = 1
-	var bar = 2 // want "declarations should never be cuddled"
+	var bar = 2    // want "declarations should never be cuddled"
 	var biz int // want "declarations should never be cuddled"
 
 	x := []string{}

testdata/remove_whitespace.go

@@ -0,0 +1,26 @@
+package testpkg
+
+import "fmt"
+
+func RemoveWhitespaceNoComments() { // want "block should not start with a whitespace"
+
+	a := 1
+	if a < 2 { // want "block should not start with a whitespace"
+
+		a = 2
+
+	} // want "block should not end with a whitespace"
+
+	switch { // want "block should not start with a whitespace"
+
+	case true:
+		fmt.Println("true")
+
+	default:
+		fmt.Println("false")
+
+	} // want "block should not end with a whitespace"
+
+	_ = a
+
+} // want "block should not end with a whitespace"

testdata/remove_whitespace.go.golden

@@ -0,0 +1,20 @@
+package testpkg
+
+import "fmt"
+
+func RemoveWhitespaceNoComments() {
+	a := 1
+	if a < 2 {
+		a = 2
+	} // want "block should not end with a whitespace"
+
+	switch {
+	case true:
+		fmt.Println("true")
+
+	default:
+		fmt.Println("false")
+	} // want "block should not end with a whitespace"
+
+	_ = a
+} // want "block should not end with a whitespace"

wsl.go

@@ -222,11 +222,12 @@ func DefaultConfig() Configuration {
 
 // Result represents the result of one error.
 type Result struct {
-	Node    ast.Node
-	FixNode ast.Node
-	Reason  string
-	NoFix   bool
-	Type    ErrorType
+	ReportAt      token.Pos
+	FixRangeStart token.Pos
+	FixRangeEnd   token.Pos
+	Reason        string
+	NoFix         bool
+	Type          ErrorType
 }
 
 // Processor is the type that keeps track of the file and fileset and holds the
@@ -416,20 +417,20 @@ func (p *Processor) parseBlockStatements(statements []ast.Stmt) {
 		// it was and use *that* statement's position
 		if p.config.ForceExclusiveShortDeclarations && cuddledWithLastStmt {
 			if p.isShortDecl(stmt) && !p.isShortDecl(previousStatement) {
-				p.addError(
-					stmt,
-					nil,
+				p.addErrorRange(
+					stmt.Pos(),
+					stmt.End(),
+					stmt.End(),
 					reasonShortDeclNotExclusive,
 					WhitespaceShouldAddAfter,
-					false,
 				)
 			} else if p.isShortDecl(previousStatement) && !p.isShortDecl(stmt) {
-				p.addError(
-					previousStatement,
-					nil,
+				p.addErrorRange(
+					previousStatement.Pos(),
+					previousStatement.Pos(),
+					previousStatement.Pos(),
 					reasonShortDeclNotExclusive,
 					WhitespaceShouldAddBefore,
-					false,
 				)
 			}
 		}
@@ -449,7 +450,7 @@ func (p *Processor) parseBlockStatements(statements []ast.Stmt) {
 				// If the variable on the line above is allowed to be
 				// cuddled, break two lines above so we keep the proper
 				// cuddling.
-				p.addWhitespaceBeforeFixOtherNodeError(n1, n2, reason)
+				p.addErrorRange(n1.Pos(), n2.Pos(), n2.Pos(), reason, WhitespaceShouldAddBefore)
 			} else {
 				// If not, break here so we separate the cuddled variable.
 				p.addWhitespaceBeforeError(n1, reason)
@@ -1140,7 +1141,15 @@ func (p *Processor) findLeadingAndTrailingWhitespaces(ident *ast.Ident, stmt, ne
 	// And now if the first statement is passed the number of allowed lines,
 	// then we had extra WS, possibly before the first comment group.
 	if p.nodeStart(firstStatement) > blockStartLine+allowedLinesBeforeFirstStatement {
-		p.addError(stmt, nil, reasonBlockStartsWithWS, WhitespaceShouldRemoveBeginning, false)
+		// TODO: We need to pick a better start of the range so we don't delete
+		// potential comments.
+		p.addErrorRange(
+			blockStartPos,
+			blockStartPos,
+			firstStatement.Pos(),
+			reasonBlockStartsWithWS,
+			WhitespaceShouldRemoveBeginning,
+		)
 	}
 
 	// If the blockEndLine is not 0 we're a regular block (not case).
@@ -1163,7 +1172,13 @@ func (p *Processor) findLeadingAndTrailingWhitespaces(ident *ast.Ident, stmt, ne
 		}
 
 		if p.nodeEnd(lastStatement) != blockEndLine-1 && !isExampleFunc(ident) {
-			p.addError(stmt, nil, reasonBlockEndsWithWS, WhitespaceShouldRemoveEnd, false)
+			p.addErrorRange(
+				stmt.End(),
+				lastStatement.End(),
+				stmt.End(),
+				reasonBlockEndsWithWS,
+				WhitespaceShouldRemoveEnd,
+			)
 		}
 
 		return
@@ -1278,32 +1293,20 @@ func isEmptyLabeledStmt(node ast.Node) bool {
 }
 
 func (p *Processor) addWhitespaceBeforeError(node ast.Node, reason string) {
-	p.addError(node, nil, reason, WhitespaceShouldAddBefore, false)
-}
-
-func (p *Processor) addWhitespaceBeforeFixOtherNodeError(reportNode, fixNode ast.Node, reason string) {
-	p.addError(reportNode, fixNode, reason, WhitespaceShouldAddBefore, false)
+	p.addErrorRange(node.Pos(), node.Pos(), node.Pos(), reason, WhitespaceShouldAddBefore)
 }
 
 func (p *Processor) addWhitespaceAfterError(node ast.Node, reason string) {
-	p.addError(node, nil, reason, WhitespaceShouldAddAfter, false)
+	p.addErrorRange(node.Pos(), node.End(), node.End(), reason, WhitespaceShouldAddAfter)
 }
 
-// Add an error for the file and line number for the current token.Pos with the
-// given reason.
-//
-//nolint:unparam // We will potentially use this in the future.
-func (p *Processor) addError(reportNode, fixNode ast.Node, reason string, errType ErrorType, noFix bool) {
-	if fixNode == nil {
-		fixNode = reportNode
-	}
-
+func (p *Processor) addErrorRange(reportAt, start, end token.Pos, reason string, errType ErrorType) {
 	p.Result = append(p.Result, Result{
-		Node:    reportNode,
-		FixNode: fixNode,
-		Reason:  reason,
-		NoFix:   noFix,
-		Type:    errType,
+		ReportAt:      reportAt,
+		FixRangeStart: start,
+		FixRangeEnd:   end,
+		Reason:        reason,
+		Type:          errType,
 	})
 }
 

wsl_test.go

@@ -2064,7 +2064,7 @@ func TestTODO(t *testing.T) {
 			t.Logf("WARNINGS: %s", p.Warnings)
 
 			for _, r := range p.Result {
-				fmt.Println(r.Node, r.Reason)
+				fmt.Println(r.FixRangeStart, r.Reason)
 			}
 
 			require.Len(t, p.Result, len(tc.expectedErrorStrings), "correct amount of errors found")