[dev.types] all: merge master into dev.types
Change-Id: Ia6964cb4e09153c15cc9c5b441373d1b3cb8f757
diff --git a/src/internal/types/ast.go b/src/internal/types/ast.go
new file mode 100644
index 0000000..8412f26
--- /dev/null
+++ b/src/internal/types/ast.go
@@ -0,0 +1,507 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file defines a collection of interfaces providing an AST abstraction,
+// for use in a type checker that operates on multiple concrete ASTs.
+
+package types
+
+import (
+ "go/ast"
+ "go/token"
+)
+
+type Pos interface {
+ IsKnown() bool
+ Before(pos Pos) bool
+ String() string
+}
+
+// Nodes
+type (
+ Node interface {
+ Pos() Pos
+ }
+
+ File interface {
+ Package() Pos
+ Name() Ident
+
+ // TODO: devise a new schema for *Len methods. DeclsLen is too clunky.
+
+ DeclsLen() int
+ Decl(i int) Decl
+
+ Node
+ }
+
+ FieldList interface {
+ Len() int
+ Field(i int) Field
+
+ Node
+ }
+
+ Field interface {
+ NamesLen() int
+ Name(i int) Ident
+ Type() Expr
+ Tag() BasicLit
+
+ Node
+ }
+)
+
+// Decls
+type (
+ Decl interface {
+ ADecl()
+ Node
+ }
+
+ BadDecl interface {
+ ABadDecl()
+ Decl
+ }
+
+ GenDecl interface {
+ Tok() token.Token
+ SpecsLen() int
+ Spec(i int) Spec
+
+ AGenDecl()
+ Decl
+ }
+
+ FuncDecl interface {
+ Recv() FieldList
+ Name() Ident
+ Type() FuncType
+ Body() BlockStmt
+
+ AFuncDecl()
+ Decl
+ }
+)
+
+// Specs
+type (
+ Spec interface {
+ ASpec()
+ Node
+ }
+
+ // TODO: consolidate these specs with decls.
+
+ ValueSpec interface {
+ NamesLen() int
+ Name(i int) Ident
+ Type() Expr
+ ValuesLen() int
+ Value(i int) Expr
+
+ AValueSpec()
+ Spec
+ }
+
+ TypeSpec interface {
+ Name() Ident
+ Assign() Pos
+ Type() Expr
+
+ ATypeSpec()
+ Spec
+ }
+
+ ImportSpec interface {
+ Path() BasicLit
+ Name() Ident
+
+ AnImportSpec()
+ Spec
+ }
+)
+
+// Exprs
+type (
+ Expr interface {
+ AnExpr()
+ Node
+ }
+
+ Ident interface {
+ Name() string
+
+ AnIdent()
+ Expr
+ }
+
+ SelectorExpr interface {
+ X() Expr
+ Sel() Ident
+
+ ASelectorExpr()
+ Expr
+ }
+
+ BadExpr interface {
+ ABadExpr()
+ Expr
+ }
+
+ DotDotDot interface {
+ Elt() Expr
+
+ ADotDotDot()
+ Expr
+ }
+
+ BasicLit interface {
+ Kind() token.Token
+ Value() string
+
+ ABasicLit()
+ Expr
+ }
+
+ FuncLit interface {
+ Type() Expr
+ Body() BlockStmt
+
+ AFuncLit()
+ Expr
+ }
+
+ CompositeLit interface {
+ Type() Expr
+ EltsLen() int
+ Elt(i int) Expr
+ Rbrace() Pos
+
+ ACompositeLit()
+ Expr
+ }
+
+ ParenExpr interface {
+ X() Expr
+
+ AParenExpr()
+ Expr
+ }
+
+ IndexExpr interface {
+ X() Expr
+ Index() Expr
+
+ AnIndexExpr()
+ Expr
+ }
+
+ SliceExpr interface {
+ X() Expr
+ Low() Expr
+ High() Expr
+ Max() Expr
+ Slice3() bool
+ Rbrack() Pos
+
+ ASliceExpr()
+ Expr
+ }
+
+ TypeAssertExpr interface {
+ X() Expr
+ Type() Expr
+
+ ATypeAssertExpr()
+ Expr
+ }
+
+ CallExpr interface {
+ ArgsLen() int
+ Arg(i int) Expr
+ Fun() Expr
+ Ellipsis() Pos
+ Rparen() Pos
+
+ ACallExpr()
+ Expr
+ }
+
+ StarExpr interface {
+ Expr
+ AStarExpr()
+
+ X() Expr
+ }
+
+ UnaryExpr interface {
+ Expr
+ AUnaryExpr()
+
+ Op() token.Token
+ X() Expr
+ }
+
+ BinaryExpr interface {
+ Op() token.Token
+ X() Expr
+ Y() Expr
+
+ ABinaryExpr()
+ Expr
+ }
+
+ KeyValueExpr interface {
+ Key() Expr
+ Value() Expr
+
+ AKeyValueExpr()
+ Expr
+ }
+
+ ArrayType interface {
+ Len() Expr
+ Elt() Expr
+
+ AnArrayType()
+ Expr
+ }
+
+ StructType interface {
+ Fields() FieldList
+
+ AStructType()
+ Expr
+ }
+
+ FuncType interface {
+ Params() FieldList
+ Results() FieldList
+
+ AFuncType()
+ Expr
+ }
+
+ InterfaceType interface {
+ Methods() FieldList
+
+ AnInterfaceType()
+ Expr
+ }
+
+ MapType interface {
+ Key() Expr
+ Value() Expr
+
+ AMapType()
+ Expr
+ }
+
+ ChanType interface {
+ // TODO: replace this return type
+ Dir() ast.ChanDir
+ Value() Expr
+
+ AChanType()
+ Expr
+ }
+)
+
+type ExprList interface {
+ Len() int
+ Expr(i int) Expr
+}
+
+// Stmts
+type (
+ Stmt interface {
+ AStmt()
+ Node
+ }
+
+ BadStmt interface {
+ ABadStmt()
+ Stmt
+ }
+
+ DeclStmt interface {
+ Decl() Decl
+
+ ADeclStmt()
+ Stmt
+ }
+
+ EmptyStmt interface {
+ AnEmptyStmt()
+ Stmt
+ }
+
+ LabeledStmt interface {
+ Label() Ident
+ Stmt() Stmt
+
+ ALabeledStmt()
+ Stmt
+ }
+
+ ExprStmt interface {
+ X() Expr
+
+ AnExprStmt()
+ Stmt
+ }
+
+ SendStmt interface {
+ Chan() Expr
+ Value() Expr
+ Arrow() Pos
+
+ ASendStmt()
+ Stmt
+ }
+
+ IncDecStmt interface {
+ Tok() token.Token
+ TokPos() Pos
+ X() Expr
+
+ AnIncDecStmt()
+ Stmt
+ }
+
+ AssignStmt interface {
+ Lhs() ExprList
+ LhsLen() int
+ LhsExpr(i int) Expr
+ RhsLen() int
+ RhsExpr(i int) Expr
+ Rhs() ExprList
+ Tok() token.Token
+ TokPos() Pos
+
+ AnAssignStmt()
+ Stmt
+ }
+
+ GoStmt interface {
+ Call() CallExpr
+
+ AGoStmt()
+ Stmt
+ }
+
+ DeferStmt interface {
+ Call() CallExpr
+
+ ADeferStmt()
+ Stmt
+ }
+
+ ReturnStmt interface {
+ Results() ExprList
+ ResultsLen() int
+ Result(i int) Expr
+ Return() Pos
+
+ AReturnStmt()
+ Stmt
+ }
+
+ BranchStmt interface {
+ Tok() token.Token
+ Label() Ident
+
+ ABranchStmt()
+ Stmt
+ }
+
+ BlockStmt interface {
+ List() StmtList
+ Lbrace() Pos
+ Rbrace() Pos
+
+ ABlockStmt()
+ Stmt
+ }
+
+ IfStmt interface {
+ Init() Stmt
+ Cond() Expr
+ Body() BlockStmt
+ Else() Stmt
+
+ AnIfStmt()
+ Stmt
+ }
+
+ CaseClause interface {
+ ListLen() int
+ Item(i int) Expr
+ Body() StmtList
+
+ ACaseClause()
+ Stmt
+ }
+
+ SwitchStmt interface {
+ Init() Stmt
+ Tag() Expr
+ Body() BlockStmt
+
+ ASwitchStmt()
+ Stmt
+ }
+
+ TypeSwitchStmt interface {
+ Init() Stmt
+ Assign() Stmt
+ Body() BlockStmt
+
+ ATypeSwitchStmt()
+ Stmt
+ }
+
+ CommClause interface {
+ Stmt
+ ACommClause()
+
+ Comm() Stmt
+ Body() StmtList
+ }
+
+ SelectStmt interface {
+ Stmt
+ ASelectStmt()
+
+ Body() BlockStmt
+ }
+
+ ForStmt interface {
+ Init() Stmt
+ Cond() Expr
+ Post() Stmt
+ Body() BlockStmt
+
+ AForStmt()
+ Stmt
+ }
+
+ RangeStmt interface {
+ Stmt
+ ARangeStmt()
+
+ Key() Expr
+ Value() Expr
+ X() Expr
+ Body() BlockStmt
+ Tok() token.Token
+ TokPos() Pos
+ }
+)
+
+type StmtList interface {
+ Len() int
+ Stmt(i int) Stmt
+}
