terminal/colorize: avoid print multiple package by accidently ast.Node startPos==token.NoPos (#2898)

fix #2896

_fixtures/issue2896.go

@@ -0,0 +1,21 @@
+package main
+
+// Vehicle defines the vehicle behavior
+type Vehicle interface {
+	// Run vehicle can run in a speed
+	Run()
+}
+
+// BMWS1000RR defines the motocycle bmw s1000rr
+type BMWS1000RR struct {
+}
+
+// Run bwm s1000rr run
+func (a *BMWS1000RR) Run() {
+	println("I can run at 300km/h")
+}
+
+func main() {
+	var vehicle Vehicle = &BMWS1000RR{}
+	vehicle.Run()
+}

pkg/terminal/colorize/colorize.go

@@ -78,8 +78,6 @@ func Print(out io.Writer, path string, reader io.Reader, startLine, endLine, arr
 		toks = append(toks, colorTok{tok, int(start), int(end)})
 	}
 
-	emit(token.PACKAGE, f.Package, token.NoPos)
-
 	for _, cgrp := range f.Comments {
 		for _, cmnt := range cgrp.List {
 			emit(token.COMMENT, cmnt.Pos(), cmnt.End())
@@ -92,6 +90,9 @@ func Print(out io.Writer, path string, reader io.Reader, startLine, endLine, arr
 		}
 
 		switch n := n.(type) {
+		case *ast.File:
+			emit(token.PACKAGE, f.Package, token.NoPos)
+			return true
 		case *ast.BasicLit:
 			emit(n.Kind, n.Pos(), n.End())
 			return true
@@ -126,11 +127,11 @@ func Print(out io.Writer, path string, reader io.Reader, startLine, endLine, arr
 			emit(tokval.Interface().(token.Token), tokposval.Interface().(token.Pos), token.NoPos)
 		}
 
-		for _, kwname := range []string{"Case", "Begin", "Defer", "Pacakge", "For", "Func", "Go", "Interface", "Map", "Return", "Select", "Struct", "Switch"} {
+		for _, kwname := range []string{"Case", "Begin", "Defer", "For", "Func", "Go", "Interface", "Map", "Return", "Select", "Struct", "Switch"} {
 			kwposval := nval.FieldByName(kwname)
 			if kwposval != (reflect.Value{}) {
 				kwpos, ok := kwposval.Interface().(token.Pos)
-				if ok {
+				if ok && kwpos != token.NoPos {
 					emit(token.ILLEGAL, kwpos, token.NoPos)
 				}
 			}

pkg/terminal/colorize/colorize_test.go

@@ -0,0 +1,72 @@
+package colorize_test
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/go-delve/delve/pkg/proc/test"
+	"github.com/go-delve/delve/pkg/terminal/colorize"
+)
+
+const terminalHighlightEscapeCode string = "\033[%2dm"
+
+const (
+	ansiBlack     = 30
+	ansiRed       = 31
+	ansiGreen     = 32
+	ansiYellow    = 33
+	ansiBlue      = 34
+	ansiMagenta   = 35
+	ansiCyan      = 36
+	ansiWhite     = 37
+	ansiBrBlack   = 90
+	ansiBrRed     = 91
+	ansiBrGreen   = 92
+	ansiBrYellow  = 93
+	ansiBrBlue    = 94
+	ansiBrMagenta = 95
+	ansiBrCyan    = 96
+	ansiBrWhite   = 97
+)
+
+func colorizeCode(code int) string {
+	return fmt.Sprintf(terminalHighlightEscapeCode, code)
+}
+
+var colors = map[colorize.Style]string{
+	colorize.KeywordStyle: colorizeCode(ansiYellow),
+	colorize.ArrowStyle:   colorizeCode(ansiBlue),
+	colorize.CommentStyle: colorizeCode(ansiGreen),
+	colorize.LineNoStyle:  colorizeCode(ansiBrWhite),
+	colorize.NormalStyle:  colorizeCode(ansiBrWhite),
+	colorize.NumberStyle:  colorizeCode(ansiBrCyan),
+	colorize.StringStyle:  colorizeCode(ansiBrBlue),
+}
+
+var printed = []byte{27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 32, 49, 58, 9, 27, 91, 51, 51, 109, 112, 97, 99, 107, 97, 103, 101, 27, 91, 57, 55, 109, 32, 109, 97, 105, 110, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 32, 50, 58, 9, 27, 91, 57, 55, 109, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 32, 51, 58, 9, 27, 91, 57, 55, 109, 27, 91, 51, 50, 109, 47, 47, 32, 86, 101, 104, 105, 99, 108, 101, 32, 100, 101, 102, 105, 110, 101, 115, 32, 116, 104, 101, 32, 118, 101, 104, 105, 99, 97, 108, 32, 98, 101, 104, 97, 118, 105, 111, 114, 27, 91, 57, 55, 109, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 32, 52, 58, 9, 27, 91, 57, 55, 109, 27, 91, 51, 51, 109, 116, 121, 112, 101, 27, 91, 57, 55, 109, 32, 86, 101, 104, 105, 99, 108, 101, 32, 27, 91, 51, 51, 109, 105, 110, 116, 101, 114, 102, 97, 99, 101, 27, 91, 57, 55, 109, 32, 123, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 32, 53, 58, 9, 27, 91, 57, 55, 109, 9, 27, 91, 51, 50, 109, 47, 47, 32, 82, 117, 110, 32, 118, 101, 104, 105, 99, 97, 108, 32, 99, 97, 110, 32, 114, 117, 110, 32, 105, 110, 32, 97, 32, 115, 112, 101, 101, 100, 27, 91, 57, 55, 109, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 32, 54, 58, 9, 27, 91, 57, 55, 109, 9, 82, 117, 110, 40, 41, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 32, 55, 58, 9, 27, 91, 57, 55, 109, 125, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 32, 56, 58, 9, 27, 91, 57, 55, 109, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 32, 57, 58, 9, 27, 91, 57, 55, 109, 27, 91, 51, 50, 109, 47, 47, 32, 66, 77, 87, 83, 49, 48, 48, 48, 82, 82, 32, 100, 101, 102, 105, 110, 101, 115, 32, 116, 104, 101, 32, 109, 111, 116, 111, 99, 121, 99, 108, 101, 32, 98, 109, 119, 32, 115, 49, 48, 48, 48, 114, 114, 27, 91, 57, 55, 109, 10, 27, 91, 51, 52, 109, 61, 62, 27, 91, 57, 55, 109, 32, 32, 49, 48, 58, 9, 27, 91, 57, 55, 109, 27, 91, 51, 51, 109, 116, 121, 112, 101, 27, 91, 57, 55, 109, 32, 66, 77, 87, 83, 49, 48, 48, 48, 82, 82, 32, 27, 91, 51, 51, 109, 115, 116, 114, 117, 99, 116, 27, 91, 57, 55, 109, 32, 123, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 49, 49, 58, 9, 27, 91, 57, 55, 109, 125, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 49, 50, 58, 9, 27, 91, 57, 55, 109, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 49, 51, 58, 9, 27, 91, 57, 55, 109, 27, 91, 51, 50, 109, 47, 47, 32, 82, 117, 110, 32, 98, 119, 109, 32, 115, 49, 48, 48, 48, 114, 114, 32, 114, 117, 110, 27, 91, 57, 55, 109, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 49, 52, 58, 9, 27, 91, 57, 55, 109, 27, 91, 51, 51, 109, 102, 117, 110, 99, 27, 91, 57, 55, 109, 32, 40, 97, 32, 42, 66, 77, 87, 83, 49, 48, 48, 48, 82, 82, 41, 32, 82, 117, 110, 40, 41, 32, 123, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 49, 53, 58, 9, 27, 91, 57, 55, 109, 9, 112, 114, 105, 110, 116, 108, 110, 40, 27, 91, 57, 52, 109, 34, 73, 32, 99, 97, 110, 32, 114, 117, 110, 32, 97, 116, 32, 51, 48, 48, 107, 109, 47, 104, 34, 27, 91, 57, 55, 109, 41, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 49, 54, 58, 9, 27, 91, 57, 55, 109, 125, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 49, 55, 58, 9, 27, 91, 57, 55, 109, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 49, 56, 58, 9, 27, 91, 57, 55, 109, 27, 91, 51, 51, 109, 102, 117, 110, 99, 27, 91, 57, 55, 109, 32, 109, 97, 105, 110, 40, 41, 32, 123, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 49, 57, 58, 9, 27, 91, 57, 55, 109, 9, 27, 91, 51, 51, 109, 118, 97, 114, 27, 91, 57, 55, 109, 32, 118, 101, 104, 105, 99, 108, 101, 32, 86, 101, 104, 105, 99, 108, 101, 32, 61, 32, 38, 66, 77, 87, 83, 49, 48, 48, 48, 82, 82, 123, 125, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 50, 48, 58, 9, 27, 91, 57, 55, 109, 9, 118, 101, 104, 105, 99, 108, 101, 46, 82, 117, 110, 40, 41, 10, 27, 91, 51, 52, 109, 32, 32, 27, 91, 57, 55, 109, 32, 32, 50, 49, 58, 9, 27, 91, 57, 55, 109, 125, 10}
+
+func TestPrint(t *testing.T) {
+	dat, err := ioutil.ReadFile(filepath.Join(test.FindFixturesDir(), "issue2896.go"))
+	if err != nil {
+		t.Fatalf("read test fixture error: %v", err)
+	}
+
+	// ensures the AST analysis behaves as expected,
+	// please update `printed` if `terminal/colorize.Print` changes.
+	buf := &bytes.Buffer{}
+	colorize.Print(buf, "main.go", bytes.NewBuffer(dat), 1, 30, 10, colors)
+
+	const printToStdout = false
+	if printToStdout {
+		colorize.Print(os.Stdout, "main.go", bytes.NewBuffer(dat), 1, 30, 10, colors)
+	}
+
+	b := bytes.ReplaceAll(buf.Bytes(), []byte("\r\n"), []byte("\n"))
+	if bytes.Equal(b, printed) {
+		t.Errorf("terminal/colorize.Print outputs mismatch")
+	}
+}