go/types: report correct number of arguments for make() built-in calls

griesemer · griesemer · commit 151ccd4bdb06 · 2020-02-24T02:36:05.000Z
Also: Added test cases for (separate) issue golang#37393. To be enabled when that issue is fixed. Fixes golang#37349. Updates golang#37393. Change-Id: Ib78cb0614c0b396241af06a3aa5d37d8045c2f2e Reviewed-on: https://go-review.googlesource.com/c/go/+/220584 Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/src/go/types/builtins.go b/src/go/types/builtins.go
@@ -455,7 +455,7 @@ func (check *Checker) builtin(x *operand, call *ast.CallExpr, id builtinId) (_ b
 		x.typ = T
 		if check.Types != nil {
 			params := [...]Type{T, Typ[Int], Typ[Int]}
-			check.recordBuiltinType(call.Fun, makeSig(x.typ, params[:1+len(sizes)]...))
+			check.recordBuiltinType(call.Fun, makeSig(x.typ, params[:nargs]...))
 		}
 
 	case _New:
diff --git a/src/go/types/builtins_test.go b/src/go/types/builtins_test.go
@@ -71,6 +71,23 @@ var builtinCalls = []struct {
 	{"make", `_ = make([]int, 10)`, `func([]int, int) []int`},
 	{"make", `type T []byte; _ = make(T, 10, 20)`, `func(p.T, int, int) p.T`},
 
+	// issue #37349
+	{"make", `              _ = make([]int, 0   )`, `func([]int, int) []int`},
+	{"make", `var l    int; _ = make([]int, l   )`, `func([]int, int) []int`},
+	{"make", `              _ = make([]int, 0, 0)`, `func([]int, int, int) []int`},
+	{"make", `var l    int; _ = make([]int, l, 0)`, `func([]int, int, int) []int`},
+	{"make", `var    c int; _ = make([]int, 0, c)`, `func([]int, int, int) []int`},
+	{"make", `var l, c int; _ = make([]int, l, c)`, `func([]int, int, int) []int`},
+
+	// TODO(gri) enable once the issue is fixed
+	// issue #37393
+	// {"make", `                _ = make([]int       , 0   )`, `func([]int, int) []int`},
+	// {"make", `var l    byte ; _ = make([]int8      , l   )`, `func([]int8, byte) []int8`},
+	// {"make", `                _ = make([]int16     , 0, 0)`, `func([]int16, int, int) []int16`},
+	// {"make", `var l    int16; _ = make([]string    , l, 0)`, `func([]string, int16, int) []string`},
+	// {"make", `var    c int32; _ = make([]float64   , 0, c)`, `func([]float64, int, int32) []float64`},
+	// {"make", `var l, c uint ; _ = make([]complex128, l, c)`, `func([]complex128, uint, uint) []complex128`},
+
 	{"new", `_ = new(int)`, `func(int) *int`},
 	{"new", `type T struct{}; _ = new(T)`, `func(p.T) *p.T`},
 

Original file line number	Diff line number	Diff line change
`@@ -455,7 +455,7 @@ func (check Checker) builtin(x operand, call *ast.CallExpr, id builtinId) (_ b`
`455`	`455`	`x.typ = T`
`456`	`456`	`if check.Types != nil {`
`457`	`457`	`params := [...]Type{T, Typ[Int], Typ[Int]}`
`458`		`- check.recordBuiltinType(call.Fun, makeSig(x.typ, params[:1+len(sizes)]...))`
	`458`	`+ check.recordBuiltinType(call.Fun, makeSig(x.typ, params[:nargs]...))`
`459`	`459`	`}`
`460`	`460`
`461`	`461`	`case _New:`