stack: refactor Func

It does cost a small bit to precalculate but it makes the code simpler.

Reduces largely the API surface.

Add wrap constant for go1.13 %w functionality.

Author: maruel

internal/htmlstack/data.go

@@ -28,11 +28,11 @@
 {{- /* Accepts a Call */ -}}
 {{- define "RenderCall" -}}
   <span class="call"><a href="{{srcURL .}}">{{.SrcName}}:{{.Line}}</a> <span class="{{funcClass .}}">
-  <a href="{{pkgURL .}}">{{.Func.PkgName}}.{{.Func.Name}}</a></span>({{template "RenderArgs" .Args}})</span>
+  <a href="{{pkgURL .}}">{{.Func.DirName}}.{{.Func.Name}}</a></span>({{template "RenderArgs" .Args}})</span>
   {{- if isDebug -}}
   <br>SrcPath: {{.SrcPath}}
   <br>LocalSrcPath: {{.LocalSrcPath}}
-  <br>Func: {{.Func.Raw}}
+  <br>Func: {{.Func.Complete}}
   <br>IsStdlib: {{.IsStdlib}}
   {{- end -}}
 {{- end -}}
@@ -44,7 +44,7 @@
       <tr>
         <td>{{$i}}</td>
         <td>
-          <a href="{{pkgURL $e}}">{{$e.Func.PkgName}}</a>
+          <a href="{{pkgURL $e}}">{{$e.Func.DirName}}</a>
         </td>
         <td>
           <a href="{{srcURL $e}}">{{$e.SrcName}}:{{$e.Line}}</a>
@@ -214,7 +214,7 @@ document.addEventListener("DOMContentLoaded", ready);
     </h1>
     {{if $e.Locked}} <span class="locked">[locked]</span>
     {{- end -}}
-    {{- if $e.CreatedBy.Func.Raw}} <span class="created">Created by: {{template "RenderCall" $e.CreatedBy}}</span>
+    {{- if $e.CreatedBy.Func.Complete}} <span class="created">Created by: {{template "RenderCall" $e.CreatedBy}}</span>
     {{- end -}}
     {{template "RenderCalls" $e.Signature.Stack}}
   {{- end -}}

internal/htmlstack/goroutines.tpl

@@ -67,13 +67,13 @@ func isDebug() bool {
 
 func funcClass(line *stack.Call) template.HTML {
 	if line.IsStdlib {
-		if line.Func.IsExported() {
+		if line.Func.IsExported {
 			return "FuncStdLibExported"
 		}
 		return "FuncStdLib"
-	} else if line.IsPkgMain() {
+	} else if line.Func.IsPkgMain {
 		return "FuncMain"
-	} else if line.Func.IsExported() {
+	} else if line.Func.IsExported {
 		return "FuncOtherExported"
 	}
 	return "FuncOther"
@@ -109,7 +109,7 @@ func pkgURL(c *stack.Call) template.URL {
 			url = "https://pkg.go.dev/"
 		}
 	}
-	if c.Func.IsExported() {
+	if c.Func.IsExported {
 		return template.URL(url + ip + "#" + symbol(&c.Func))
 	}
 	return template.URL(url + ip)
@@ -224,15 +224,7 @@ func splitTag(s string) (string, string, template.URL) {
 // All of godoc/gddo, pkg.go.dev and golang.org/godoc use the same symbol
 // reference format.
 func symbol(f *stack.Func) template.URL {
-	i := strings.LastIndexByte(f.Raw, '/')
-	if i == -1 {
-		return ""
-	}
-	j := strings.IndexByte(f.Raw[i:], '.')
-	if j == -1 {
-		return ""
-	}
-	s := f.Raw[i+j+1:]
+	s := f.Name
 	if reMethodSymbol.MatchString(s) {
 		// Transform the method form.
 		s = reMethodSymbol.ReplaceAllString(s, "$1$2")

internal/htmlstack/htmlstack.go

@@ -228,7 +228,7 @@ func TestSymbol(t *testing.T) {
 		},
 		{
 			newFunc("main.baz"),
-			"",
+			"baz",
 		},
 	}
 	for i, line := range data {
@@ -262,7 +262,11 @@ func BenchmarkWrite(b *testing.B) {
 //
 
 func newFunc(s string) stack.Func {
-	return stack.Func{Raw: s}
+	f := stack.Func{}
+	if err := f.Init(s); err != nil {
+		panic(err)
+	}
+	return f
 }
 
 func newCall(f string, a stack.Args, s string, l int) stack.Call {

internal/htmlstack/htmlstack_test.go

@@ -60,11 +60,10 @@ func (pf pathFormat) formatCall(c *stack.Call) string {
 }
 
 func (pf pathFormat) createdByString(s *stack.Signature) string {
-	created := s.CreatedBy.Func.PkgDotName()
-	if created == "" {
+	if s.CreatedBy.Func.DirName == "" {
 		return ""
 	}
-	return created + " @ " + pf.formatCall(&s.CreatedBy)
+	return s.CreatedBy.Func.DirName + "." + s.CreatedBy.Func.Name + " @ " + pf.formatCall(&s.CreatedBy)
 }
 
 // calcLengths returns the maximum length of the source lines and package names.
@@ -76,7 +75,7 @@ func calcLengths(buckets []*stack.Bucket, pf pathFormat) (int, int) {
 			if l := len(pf.formatCall(&line)); l > srcLen {
 				srcLen = l
 			}
-			if l := len(line.Func.PkgName()); l > pkgLen {
+			if l := len(line.Func.DirName); l > pkgLen {
 				pkgLen = l
 			}
 		}
@@ -88,13 +87,13 @@ func calcLengths(buckets []*stack.Bucket, pf pathFormat) (int, int) {
 // the type of package the function is in.
 func (p *Palette) functionColor(line *stack.Call) string {
 	if line.IsStdlib {
-		if line.Func.IsExported() {
+		if line.Func.IsExported {
 			return p.FuncStdLibExported
 		}
 		return p.FuncStdLib
-	} else if line.IsPkgMain() {
+	} else if line.Func.IsPkgMain {
 		return p.FuncMain
-	} else if line.Func.IsExported() {
+	} else if line.Func.IsExported {
 		return p.FuncOtherExported
 	}
 	return p.FuncOther
@@ -131,9 +130,9 @@ func (p *Palette) BucketHeader(bucket *stack.Bucket, pf pathFormat, multipleBuck
 func (p *Palette) callLine(line *stack.Call, srcLen, pkgLen int, pf pathFormat) string {
 	return fmt.Sprintf(
 		"    %s%-*s %s%-*s %s%s%s(%s)%s",
-		p.Package, pkgLen, line.Func.PkgName(),
+		p.Package, pkgLen, line.Func.DirName,
 		p.SrcFile, srcLen, pf.formatCall(line),
-		p.functionColor(line), line.Func.Name(),
+		p.functionColor(line), line.Func.Name,
 		p.Arguments, &line.Args,
 		p.EOLReset)
 }

internal/ui.go

@@ -45,13 +45,13 @@ func TestCalcLengths(t *testing.T) {
 	// When printing, it prints the remote path, not the transposed local path.
 	compareString(t, "/home/user/go/src/foo/baz.go:123", fullPath.formatCall(&b[0].Signature.Stack.Calls[0]))
 	compareInt(t, len("/home/user/go/src/foo/baz.go:123"), srcLen)
-	compareString(t, "main", b[0].Signature.Stack.Calls[0].Func.PkgName())
+	compareString(t, "main", b[0].Signature.Stack.Calls[0].Func.ImportPath)
 	compareInt(t, len("main"), pkgLen)
 
 	srcLen, pkgLen = calcLengths(b, basePath)
 	compareString(t, "baz.go:123", basePath.formatCall(&b[0].Signature.Stack.Calls[0]))
 	compareInt(t, len("baz.go:123"), srcLen)
-	compareString(t, "main", b[0].Signature.Stack.Calls[0].Func.PkgName())
+	compareString(t, "main", b[0].Signature.Stack.Calls[0].Func.ImportPath)
 	compareInt(t, len("main"), pkgLen)
 }
 
@@ -160,7 +160,11 @@ func TestStackLines(t *testing.T) {
 //
 
 func newFunc(s string) stack.Func {
-	return stack.Func{Raw: s}
+	f := stack.Func{}
+	if err := f.Init(s); err != nil {
+		panic(err)
+	}
+	return f
 }
 
 func newCallLocal(f string, a stack.Args, s string, l int) stack.Call {

internal/ui_test.go

@@ -489,7 +489,9 @@ func (s *scanningState) scan(line string) (string, error) {
 
 	case gotFileFunc:
 		if match := reCreated.FindStringSubmatch(trimmed); match != nil {
-			cur.CreatedBy.Func.Raw = match[1]
+			if err := cur.CreatedBy.Func.Init(match[1]); err != nil {
+				return "", err
+			}
 			s.state = gotCreated
 			return "", nil
 		}
@@ -532,7 +534,9 @@ func (s *scanningState) scan(line string) (string, error) {
 			return "", nil
 		}
 		if match := reCreated.FindStringSubmatch(trimmed); match != nil {
-			cur.CreatedBy.Func.Raw = match[1]
+			if err := cur.CreatedBy.Func.Init(match[1]); err != nil {
+				return "", err
+			}
 			s.state = gotCreated
 			return "", nil
 		}
@@ -700,7 +704,9 @@ func (s *scanningState) scan(line string) (string, error) {
 // Uses reFunc.
 func parseFunc(c *Call, line string) (bool, error) {
 	if match := reFunc.FindStringSubmatch(line); match != nil {
-		c.Func.Raw = match[1]
+		if err := c.Func.Init(match[1]); err != nil {
+			return true, err
+		}
 		for _, a := range strings.Split(match[2], ", ") {
 			if a == "..." {
 				c.Args.Elided = true