go.tools/go/types: call Context.Ident for selectors

Fixes golang/go#5669.

R=adonovan
CC=golang-dev
https://golang.org/cl/9714045

go/types/api.go

@@ -64,9 +64,9 @@ type Context struct {
 	// filename:line:column: message
 	Error func(err error)
 
-	// If Ident != nil, it is called for each identifier id in the AST
-	// (including package names, dots "." of dot-imports, and blank "_"
-	// identifiers), and obj is the object denoted by ident. The object
+	// If Ident != nil, it is called for each identifier id that is type-
+	// checked (including package names, dots "." of dot-imports, and blank
+	// "_" identifiers), and obj is the object denoted by ident. The object
 	// is nil if the identifier was not declared. Ident may be called
 	// multiple times for the same identifier (e.g., for typed variable
 	// declarations with multiple initialization statements); but Ident

go/types/expr.go

@@ -1328,9 +1328,10 @@ func (check *checker) rawExpr(x *operand, e ast.Expr, hint Type, iota int, cycle
 			check.invalidOp(e.Pos(), "%s has no single field or method %s", x, sel)
 			goto Error
 		}
+		check.callIdent(e.Sel, res.obj)
 		if x.mode == typexpr {
 			// method expression
-			sig, ok := res.typ.(*Signature)
+			sig, ok := res.obj.Type().(*Signature)
 			if !ok {
 				check.invalidOp(e.Pos(), "%s has no method %s", x, sel)
 				goto Error
@@ -1352,7 +1353,7 @@ func (check *checker) rawExpr(x *operand, e ast.Expr, hint Type, iota int, cycle
 		} else {
 			// regular selector
 			x.mode = res.mode
-			x.typ = res.typ
+			x.typ = res.obj.Type()
 		}
 
 	case *ast.IndexExpr:

go/types/operand.go

@@ -209,8 +209,8 @@ func (x *operand) isInteger() bool {
 // lookupResult represents the result of a struct field/method lookup.
 type lookupResult struct {
 	mode  operandMode
-	typ   Type
-	index []int // field index sequence; nil for methods
+	obj   Object // *Field or *Func; valid if mode != invalid
+	index []int  // field index sequence; nil for methods
 }
 
 type embeddedType struct {
@@ -232,7 +232,7 @@ func lookupFieldBreadthFirst(list []embeddedType, pkg *Package, name string) (re
 	var next []embeddedType
 
 	// potentialMatch is invoked every time a match is found.
-	potentialMatch := func(multiples bool, mode operandMode, typ Type) bool {
+	potentialMatch := func(multiples bool, mode operandMode, obj Object) bool {
 		if multiples || res.mode != invalid {
 			// name appeared already at this level - annihilate
 			res.mode = invalid
@@ -240,7 +240,7 @@ func lookupFieldBreadthFirst(list []embeddedType, pkg *Package, name string) (re
 		}
 		// first appearance of name
 		res.mode = mode
-		res.typ = typ
+		res.obj = obj
 		res.index = nil
 		return true
 	}
@@ -267,7 +267,7 @@ func lookupFieldBreadthFirst(list []embeddedType, pkg *Package, name string) (re
 			if obj := typ.methods.Lookup(pkg, name); obj != nil {
 				m := obj.(*Func)
 				assert(m.typ != nil)
-				if !potentialMatch(e.multiples, value, m.typ) {
+				if !potentialMatch(e.multiples, value, m) {
 					return // name collision
 				}
 			}
@@ -282,7 +282,7 @@ func lookupFieldBreadthFirst(list []embeddedType, pkg *Package, name string) (re
 					f := obj.(*Field)
 					if f.isMatch(pkg, name) {
 						assert(f.typ != nil)
-						if !potentialMatch(e.multiples, variable, f.typ) {
+						if !potentialMatch(e.multiples, variable, f) {
 							return // name collision
 						}
 						var index []int
@@ -317,7 +317,7 @@ func lookupFieldBreadthFirst(list []embeddedType, pkg *Package, name string) (re
 				if obj := t.methods.Lookup(pkg, name); obj != nil {
 					m := obj.(*Func)
 					assert(m.typ != nil)
-					if !potentialMatch(e.multiples, value, m.typ) {
+					if !potentialMatch(e.multiples, value, m) {
 						return // name collision
 					}
 				}
@@ -367,7 +367,7 @@ func lookupField(typ Type, pkg *Package, name string) lookupResult {
 		if obj := t.methods.Lookup(pkg, name); obj != nil {
 			m := obj.(*Func)
 			assert(m.typ != nil)
-			return lookupResult{value, m.typ, nil}
+			return lookupResult{value, m, nil}
 		}
 		typ = t.underlying
 	}
@@ -381,7 +381,7 @@ func lookupField(typ Type, pkg *Package, name string) lookupResult {
 		for i, obj := range t.fields.entries {
 			f := obj.(*Field)
 			if f.isMatch(pkg, name) {
-				return lookupResult{variable, f.typ, []int{i}}
+				return lookupResult{variable, f, []int{i}}
 			}
 			if f.anonymous {
 				// Possible optimization: If the embedded type
@@ -402,7 +402,7 @@ func lookupField(typ Type, pkg *Package, name string) lookupResult {
 		if obj := t.methods.Lookup(pkg, name); obj != nil {
 			m := obj.(*Func)
 			assert(m.typ != nil)
-			return lookupResult{value, m.typ, nil}
+			return lookupResult{value, m, nil}
 		}
 	}
 

go/types/predicates.go

@@ -289,7 +289,7 @@ func missingMethod(typ Type, T *Interface) (method *Func, wrongType bool) {
 		for _, obj := range T.methods.entries {
 			m := obj.(*Func)
 			res := lookupField(ityp, m.pkg, m.name) // TODO(gri) no need to go via lookupField
-			if res.mode != invalid && !IsIdentical(res.typ, m.typ) {
+			if res.mode != invalid && !IsIdentical(res.obj.Type(), m.typ) {
 				return m, true
 			}
 		}
@@ -303,7 +303,7 @@ func missingMethod(typ Type, T *Interface) (method *Func, wrongType bool) {
 		if res.mode == invalid {
 			return m, false
 		}
-		if !IsIdentical(res.typ, m.typ) {
+		if !IsIdentical(res.obj.Type(), m.typ) {
 			return m, true
 		}
 	}

go/types/resolver_test.go

@@ -43,6 +43,8 @@ var sources = []string{
 	type I interface{ m() }
 	var _ = T{a: 1, b: 2, c: 3}
 	func (_ T) m() {}
+	var i I
+	var _ = i.m
 	`,
 }