From 62c40878e47c71b1e291e9c3064d76c16a6f9d69 Mon Sep 17 00:00:00 2001 From: Rob Findley Date: Thu, 3 Jun 2021 10:12:37 -0400 Subject: [PATCH] [dev.typeparams] go/types: better recv Var for method expressions This is a port of CL 320489 to go/types, adjusted to be consistent about named/unnamed parameters. TestEvalPos was failing without this addition. For #46209 Change-Id: Icdf86e84ebce8ccdb7846a63b5605e360e2b8781 Reviewed-on: https://go-review.googlesource.com/c/go/+/324733 Trust: Robert Findley Run-TryBot: Robert Findley TryBot-Result: Go Bot Reviewed-by: Robert Griesemer --- src/go/types/call.go | 25 +++++++++++++++++++++++-- src/go/types/testdata/check/decls0.src | 8 ++++---- 2 files changed, 27 insertions(+), 6 deletions(-) diff --git a/src/go/types/call.go b/src/go/types/call.go index 631ea426c6..3a04121e98 100644 --- a/src/go/types/call.go +++ b/src/go/types/call.go @@ -575,17 +575,38 @@ func (check *Checker) selector(x *operand, e *ast.SelectorExpr) { check.recordSelection(e, MethodExpr, x.typ, m, index, indirect) + sig := m.typ.(*Signature) + if sig.recv == nil { + check.error(e, _InvalidDeclCycle, "illegal cycle in method declaration") + goto Error + } + // the receiver type becomes the type of the first function // argument of the method expression's function type var params []*Var - sig := m.typ.(*Signature) if sig.params != nil { params = sig.params.vars } + // Be consistent about named/unnamed parameters. + needName := true + for _, param := range params { + if param.Name() == "" { + needName = false + break + } + } + name := "" + if needName { + name = sig.recv.name + if name == "" { + name = "_" + } + } + params = append([]*Var{NewVar(sig.recv.pos, sig.recv.pkg, name, x.typ)}, params...) x.mode = value x.typ = &Signature{ tparams: sig.tparams, - params: NewTuple(append([]*Var{NewVar(token.NoPos, check.pkg, "_", x.typ)}, params...)...), + params: NewTuple(params...), results: sig.results, variadic: sig.variadic, } diff --git a/src/go/types/testdata/check/decls0.src b/src/go/types/testdata/check/decls0.src index 5ad8f53f65..09904bb303 100644 --- a/src/go/types/testdata/check/decls0.src +++ b/src/go/types/testdata/check/decls0.src @@ -187,10 +187,10 @@ func f4() (x *f4 /* ERROR "not a type" */ ) { return } // TODO(#43215) this should be detected as a cycle error func f5([unsafe.Sizeof(f5)]int) {} -func (S0) m1 (x S0 /* ERROR value .* is not a type */ .m1) {} -func (S0) m2 (x *S0 /* ERROR value .* is not a type */ .m2) {} -func (S0) m3 () (x S0 /* ERROR value .* is not a type */ .m3) { return } -func (S0) m4 () (x *S0 /* ERROR value .* is not a type */ .m4) { return } +func (S0) m1 (x S0 /* ERROR illegal cycle in method declaration */ .m1) {} +func (S0) m2 (x *S0 /* ERROR illegal cycle in method declaration */ .m2) {} +func (S0) m3 () (x S0 /* ERROR illegal cycle in method declaration */ .m3) { return } +func (S0) m4 () (x *S0 /* ERROR illegal cycle in method declaration */ .m4) { return } // interfaces may not have any blank methods type BlankI interface {