cue/ast: reorganization of node types
Change-Id: Ib61eb58bb35c301898a67460bde783a7ead7cd70
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/3484
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
diff --git a/cue/ast/ast.go b/cue/ast/ast.go
index 5d0dce4..864fe2f 100644
--- a/cue/ast/ast.go
+++ b/cue/ast/ast.go
@@ -90,24 +90,9 @@
exprNode()
}
-func (*BadExpr) exprNode() {}
-func (*Ident) exprNode() {}
-func (*BasicLit) exprNode() {}
-func (*Interpolation) exprNode() {}
-func (*StructLit) exprNode() {}
-func (*ListLit) exprNode() {}
-func (*Ellipsis) exprNode() {}
+type expr struct{}
-// func (*Comprehension) exprNode() {}
-func (*ListComprehension) exprNode() {}
-func (*ParenExpr) exprNode() {}
-func (*SelectorExpr) exprNode() {}
-func (*IndexExpr) exprNode() {}
-func (*SliceExpr) exprNode() {}
-func (*CallExpr) exprNode() {}
-func (*UnaryExpr) exprNode() {}
-func (*BinaryExpr) exprNode() {}
-func (*BottomLit) exprNode() {}
+func (expr) exprNode() {}
// A Decl node is implemented by all declarations.
type Decl interface {
@@ -115,17 +100,9 @@
declNode()
}
-func (*Field) declNode() {}
-func (*Comprehension) declNode() {}
-func (*ImportDecl) declNode() {}
-func (*BadDecl) declNode() {}
-func (*EmbedDecl) declNode() {}
-func (*Alias) declNode() {}
-func (*Ellipsis) declNode() {}
+type decl struct{}
-// Not technically declarations, but appearing at the same level.
-func (*Package) declNode() {}
-func (*CommentGroup) declNode() {}
+func (decl) declNode() {}
// A Label is any production that can be used as a LHS label.
type Label interface {
@@ -143,6 +120,10 @@
clauseNode()
}
+type clause struct{}
+
+func (clause) clauseNode() {}
+
func (x *ForClause) clauseNode() {}
func (x *IfClause) clauseNode() {}
func (x *Alias) clauseNode() {}
@@ -213,6 +194,8 @@
// <0> Label <1> ":" <2> Expr <3> "," <4>
Position int8
List []*Comment // len(List) > 0
+
+ decl
}
func (g *CommentGroup) Pos() token.Pos { return getPos(g) }
@@ -294,9 +277,10 @@
// An Attribute provides meta data about a field.
type Attribute struct {
- comments
At token.Pos
Text string // must be a valid attribute format.
+
+ comments
}
func (a *Attribute) Pos() token.Pos { return a.At }
@@ -305,7 +289,6 @@
// A Field represents a field declaration in a struct.
type Field struct {
- comments
Label Label // must have at least one element.
Optional token.Pos
@@ -316,6 +299,9 @@
Value Expr // the value associated with this field.
Attrs []*Attribute
+
+ comments
+ decl
}
func (d *Field) Pos() token.Pos { return d.Label.Pos() }
@@ -332,10 +318,12 @@
// An Alias binds another field to the alias name in the current struct.
type Alias struct {
- comments
Ident *Ident // field name, always an Ident
Equal token.Pos // position of "="
Expr Expr // An Ident or SelectorExpr
+
+ comments
+ decl
}
func (a *Alias) Pos() token.Pos { return a.Ident.Pos() }
@@ -344,9 +332,11 @@
// A Comprehension node represents a comprehension declaration.
type Comprehension struct {
- comments
Clauses []Clause // There must be at least one clause.
Value Expr // Must be a struct
+
+ comments
+ decl
}
func (x *Comprehension) Pos() token.Pos { return getPos(x) }
@@ -366,20 +356,22 @@
// created. This is different from an ErrorExpr which represents
// an explicitly marked error in the source.
type BadExpr struct {
- comments
From, To token.Pos // position range of bad expression
+
+ comments
+ expr
}
// A BottomLit indicates an error.
type BottomLit struct {
- comments
Bottom token.Pos
+
+ comments
+ expr
}
// An Ident node represents an left-hand side identifier.
type Ident struct {
- label
- comments
NamePos token.Pos // identifier position
// This LHS path element may be an identifier. Possible forms:
@@ -390,24 +382,31 @@
Scope Node // scope in which node was found or nil if referring directly
Node Node
+
+ comments
+ label
+ expr
}
// A TemplateLabel represents a field template declaration in a struct.
type TemplateLabel struct {
- label
- comments
Langle token.Pos
Ident *Ident
Rangle token.Pos
+
+ comments
+ label
}
// A BasicLit node represents a literal of basic type.
type BasicLit struct {
- label
- comments
ValuePos token.Pos // literal position
Kind token.Token // INT, FLOAT, DURATION, or STRING
Value string // literal string; e.g. 42, 0x7f, 3.14, 1_234_567, 1e-9, 2.4i, 'a', '\x7f', "foo", or '\m\n\o'
+
+ comments
+ expr
+ label
}
// NewString creates a new BasicLit with a string value without position.
@@ -425,45 +424,55 @@
// A Interpolation node represents a string or bytes interpolation.
type Interpolation struct {
- label
- comments
Elts []Expr // interleaving of strings and expressions.
+
+ comments
+ expr
+ label
}
// A StructLit node represents a literal struct.
type StructLit struct {
- comments
Lbrace token.Pos // position of "{"
Elts []Decl // list of elements; or nil
Rbrace token.Pos // position of "}"
+
+ comments
+ expr
}
// A ListLit node represents a literal list.
type ListLit struct {
- comments
Lbrack token.Pos // position of "["
Elts []Expr // list of composite elements; or nil
Rbrack token.Pos // position of "]"
+
+ comments
+ expr
}
type Ellipsis struct {
- comments
Ellipsis token.Pos // open list if set
Type Expr // type for the remaining elements
+
+ comments
+ decl
+ expr
}
// A ListComprehension node represents as list comprehension.
type ListComprehension struct {
- comments
Lbrack token.Pos // position of "["
Expr Expr
Clauses []Clause // Feed or Guard (TODO let)
Rbrack token.Pos // position of "]"
+
+ comments
+ expr
}
// A ForClause node represents a for clause in a comprehension.
type ForClause struct {
- comments
For token.Pos
Key *Ident // allow pattern matching?
// TODO: change to Comma
@@ -471,28 +480,37 @@
Value *Ident // allow pattern matching?
In token.Pos
Source Expr
+
+ comments
+ clause
}
// A IfClause node represents an if guard clause in a comprehension.
type IfClause struct {
- comments
If token.Pos
Condition Expr
+
+ comments
+ clause
}
// A ParenExpr node represents a parenthesized expression.
type ParenExpr struct {
- comments
Lparen token.Pos // position of "("
X Expr // parenthesized expression
Rparen token.Pos // position of ")"
+
+ comments
+ expr
}
// A SelectorExpr node represents an expression followed by a selector.
type SelectorExpr struct {
- comments
X Expr // expression
Sel *Ident // field selector
+
+ comments
+ expr
}
// NewSel creates a sequence of selectors.
@@ -506,30 +524,36 @@
// An IndexExpr node represents an expression followed by an index.
type IndexExpr struct {
- comments
X Expr // expression
Lbrack token.Pos // position of "["
Index Expr // index expression
Rbrack token.Pos // position of "]"
+
+ comments
+ expr
}
// An SliceExpr node represents an expression followed by slice indices.
type SliceExpr struct {
- comments
X Expr // expression
Lbrack token.Pos // position of "["
Low Expr // begin of slice range; or nil
High Expr // end of slice range; or nil
Rbrack token.Pos // position of "]"
+
+ comments
+ expr
}
// A CallExpr node represents an expression followed by an argument list.
type CallExpr struct {
- comments
Fun Expr // function expression
Lparen token.Pos // position of "("
Args []Expr // function arguments; or nil
Rparen token.Pos // position of ")"
+
+ comments
+ expr
}
// NewCall creates a new CallExpr.
@@ -540,19 +564,23 @@
// A UnaryExpr node represents a unary expression.
type UnaryExpr struct {
- comments
OpPos token.Pos // position of Op
Op token.Token // operator
X Expr // operand
+
+ comments
+ expr
}
// A BinaryExpr node represents a binary expression.
type BinaryExpr struct {
- comments
X Expr // left operand
OpPos token.Pos // position of Op
Op token.Token // operator
Y Expr // right operand
+
+ comments
+ expr
}
// token.Pos and End implementations for expression/type nodes.
@@ -641,7 +669,7 @@
// NewIdent creates a new Ident without position.
// Useful for ASTs generated by code other than the Go
func NewIdent(name string) *Ident {
- return &Ident{label{}, comments{}, token.NoPos, name, nil, nil}
+ return &Ident{token.NoPos, name, nil, nil, comments{}, label{}, expr{}}
}
func (id *Ident) String() string {
@@ -656,12 +684,15 @@
// An ImportSpec node represents a single package import.
type ImportSpec struct {
- comments
Name *Ident // local package name (including "."); or nil
Path *BasicLit // import path
EndPos token.Pos // end of spec (overrides Path.Pos if nonzero)
+
+ comments
}
+func (*ImportSpec) specNode() {}
+
func NewImport(name *Ident, importPath string) *ImportSpec {
importPath = strconv.Quote(importPath)
path := &BasicLit{Kind: token.STRING, Value: importPath}
@@ -693,18 +724,22 @@
// syntax errors for which no correct declaration nodes can be
// created.
type BadDecl struct {
- comments
From, To token.Pos // position range of bad declaration
+
+ comments
+ decl
}
// A ImportDecl node represents a series of import declarations. A valid
// Lparen position (Lparen.Line > 0) indicates a parenthesized declaration.
type ImportDecl struct {
- comments
Import token.Pos
Lparen token.Pos // position of '(', if any
Specs []*ImportSpec
Rparen token.Pos // position of ')', if any
+
+ comments
+ decl
}
type Spec interface {
@@ -712,18 +747,16 @@
specNode()
}
-func (*ImportSpec) specNode() {}
-
-func (*Package) specNode() {}
-
// An EmbedDecl node represents a single expression used as a declaration.
// The expressions in this declaration is what will be emitted as
// configuration output.
//
// An EmbedDecl may only appear at the top level.
type EmbedDecl struct {
- comments
Expr Expr
+
+ comments
+ decl
}
// Pos and End implementations for declaration nodes.
@@ -757,11 +790,12 @@
// via Doc and Comment fields.
type File struct {
Filename string
- comments
- Decls []Decl // top-level declarations; or nil
+ Decls []Decl // top-level declarations; or nil
Imports []*ImportSpec // imports in this file
Unresolved []*Ident // unresolved identifiers in this file
+
+ comments
}
func (f *File) Pos() token.Pos {
@@ -794,9 +828,11 @@
// A Package represents a package clause.
type Package struct {
- comments
PackagePos token.Pos // position of "package" pseudo-keyword
Name *Ident // package name
+
+ comments
+ decl
}
func (p *Package) Pos() token.Pos { return getPos(p) }
diff --git a/cue/parser/parser_test.go b/cue/parser/parser_test.go
index 6bf83f0..79bf9a8 100644
--- a/cue/parser/parser_test.go
+++ b/cue/parser/parser_test.go
@@ -544,7 +544,7 @@
if sel == nil {
t.Fatalf("found no *SelectorExpr: %#v %s", f.Decls[0], debugStr(f))
}
- const wantSel = "&{{<nil>} fmt _}"
+ const wantSel = "&{fmt _ {<nil>} {}}"
if fmt.Sprint(sel) != wantSel {
t.Fatalf("found selector %v, want %s", sel, wantSel)
}
