cmd/api: fix signatures like func(x, y, z int)

Fixes writing of function parameter, result lists which
consist of multiple named or unnamed items with same type.

Fixes #4011.

R=golang-dev, bsiegert, bradfitz, rsc
CC=golang-dev
https://golang.org/cl/6475062

diff --git a/src/cmd/api/goapi.go b/src/cmd/api/goapi.go
index a7485e0447fb9df462091c3243e7579e10ec5745..ad2c5770a054c15c35d449346233f8705e3d35ff 100644 (file)
--- a/src/cmd/api/goapi.go
+++ b/src/cmd/api/goapi.go
@@ -1017,18 +1017,38 @@ func (w *Walker) walkFuncDecl(f *ast.FuncDecl) {
 
 func (w *Walker) funcSigString(ft *ast.FuncType) string {
        var b bytes.Buffer
+       writeField := func(b *bytes.Buffer, f *ast.Field) {
+               if n := len(f.Names); n > 1 {
+                       for i := 0; i < n; i++ {
+                               if i > 0 {
+                                       b.WriteString(", ")
+                               }
+                               b.WriteString(w.nodeString(w.namelessType(f.Type)))
+                       }
+               } else {
+                       b.WriteString(w.nodeString(w.namelessType(f.Type)))
+               }
+       }
        b.WriteByte('(')
        if ft.Params != nil {
                for i, f := range ft.Params.List {
                        if i > 0 {
                                b.WriteString(", ")
                        }
-                       b.WriteString(w.nodeString(w.namelessType(f.Type)))
+                       writeField(&b, f)
                }
        }
        b.WriteByte(')')
        if ft.Results != nil {
-               if nr := len(ft.Results.List); nr > 0 {
+               nr := 0
+               for _, f := range ft.Results.List {
+                       if n := len(f.Names); n > 1 {
+                               nr += n
+                       } else {
+                               nr++
+                       }
+               }
+               if nr > 0 {
                        b.WriteByte(' ')
                        if nr > 1 {
                                b.WriteByte('(')
@@ -1037,7 +1057,7 @@ func (w *Walker) funcSigString(ft *ast.FuncType) string {
                                if i > 0 {
                                        b.WriteString(", ")
                                }
-                               b.WriteString(w.nodeString(w.namelessType(f.Type)))
+                               writeField(&b, f)
                        }
                        if nr > 1 {
                                b.WriteByte(')')

diff --git a/src/cmd/api/testdata/src/pkg/p3/golden.txt b/src/cmd/api/testdata/src/pkg/p3/golden.txt
new file mode 100644 (file)
index 0000000..579692f
--- /dev/null
+++ b/src/cmd/api/testdata/src/pkg/p3/golden.txt
@@ -0,0 +1,3 @@
+pkg p3, method (*ThirdBase) GoodPlayer() (int, int, int)
+pkg p3, func BadHop(int, int, int) (bool, bool, *ThirdBase, *ThirdBase, error)
+pkg p3, type ThirdBase struct

diff --git a/src/cmd/api/testdata/src/pkg/p3/p3.go b/src/cmd/api/testdata/src/pkg/p3/p3.go
new file mode 100644 (file)
index 0000000..1b2b1a4
--- /dev/null
+++ b/src/cmd/api/testdata/src/pkg/p3/p3.go
@@ -0,0 +1,6 @@
+package p3
+
+type ThirdBase struct{}
+
+func (tb *ThirdBase) GoodPlayer() (i, j, k int)
+func BadHop(i, j, k int) (l, m bool, n, o *ThirdBase, err error)