cmd/cue: rewrite quoted identifiers
- also fixes formatting of label aliasing
- add ast.IsValidIdent
- deprecate ast.QuoteIdent and ast.ParseIdent
Change-Id: Id058b37bcbd480ba016d61df1caac54956e31346
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/3870
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
diff --git a/cmd/cue/cmd/fix.go b/cmd/cue/cmd/fix.go
index 92a859e..e4391fc 100644
--- a/cmd/cue/cmd/fix.go
+++ b/cmd/cue/cmd/fix.go
@@ -15,6 +15,7 @@
package cmd
import (
+ "fmt"
"strconv"
"strings"
@@ -58,7 +59,11 @@
return true
}, nil)
+ // Referred nodes and used identifiers.
referred := map[ast.Node]string{}
+ used := map[string]bool{}
+ replacement := map[ast.Node]string{}
+
ast.Walk(f, func(n ast.Node) bool {
if i, ok := n.(*ast.Ident); ok {
str, err := ast.ParseIdent(i)
@@ -66,10 +71,22 @@
return false
}
referred[i.Node] = str
+ used[str] = true
}
return true
}, nil)
+ num := 0
+ newIdent := func() string {
+ for num++; ; num++ {
+ str := fmt.Sprintf("X%d", num)
+ if !used[str] {
+ used[str] = true
+ return str
+ }
+ }
+ }
+
// Rewrite TemplateLabel to ListLit.
// Note: there is a chance that the name will clash with the
// scope in which it is defined. We drop the alias if it is not
@@ -99,23 +116,61 @@
if !ok {
break
}
- b, ok := x.Label.(*ast.BasicLit)
- if !ok || b.Kind != token.STRING {
- break
+ switch b := x.Label.(type) {
+ case *ast.BasicLit:
+ if b.Kind != token.STRING {
+ return true
+ }
+ str, err := strconv.Unquote(b.Value)
+ if err != nil || str != m {
+ return true
+ }
+
+ case *ast.Ident:
+ str, err := ast.ParseIdent(b)
+ if err != nil || str != m || str == b.Name {
+ return true
+ }
+ if ast.IsValidIdent(str) {
+ x.Label = astutil.CopyMeta(ast.NewIdent(str), x.Label).(ast.Label)
+ return true
+ }
}
- str, err := strconv.Unquote(b.Value)
- if err != nil || str != m {
- break
- }
- str, err = ast.QuoteIdent(str)
- if err != nil {
- return false
- }
- x.Label = astutil.CopyMeta(ast.NewIdent(str), x.Label).(ast.Label)
+
+ ident := newIdent()
+ replacement[x.Value] = ident
+ expr := x.Label.(ast.Expr)
+ expr = &ast.Alias{Ident: ast.NewIdent(ident), Expr: expr}
+ ast.SetRelPos(x.Label, token.NoRelPos)
+ x.Label = astutil.CopyMeta(expr, x.Label).(ast.Label)
}
return true
}, nil).(*ast.File)
+ // Replace quoted references with their alias identifier.
+ astutil.Apply(f, func(c astutil.Cursor) bool {
+ n := c.Node()
+ switch x := n.(type) {
+ case *ast.Ident:
+ if r, ok := replacement[x.Node]; ok {
+ c.Replace(astutil.CopyMeta(ast.NewIdent(r), n))
+ break
+ }
+ str, err := ast.ParseIdent(x)
+ if err != nil || str == x.Name {
+ break
+ }
+ // Either the identifier is valid, in which can be replaced simply
+ // as here, or it is a complicated identifier and the original
+ // destination must have been quoted, in which case it is handled
+ // above.
+ if ast.IsValidIdent(str) {
+ c.Replace(astutil.CopyMeta(ast.NewIdent(str), n))
+ }
+ }
+ return true
+ }, nil)
+
// TODO: we are probably reintroducing slices. Disable for now.
//
// Rewrite slice expression.
diff --git a/cmd/cue/cmd/fix_test.go b/cmd/cue/cmd/fix_test.go
index 4ddeca2..49019e3 100644
--- a/cmd/cue/cmd/fix_test.go
+++ b/cmd/cue/cmd/fix_test.go
@@ -35,21 +35,47 @@
"baz": ` + "`foo-bar`" + `
a: {
- "qux": 3
+ // qux
+ "qux": 3 // qux line
+ // qux-quux
"qux-quux": qux
"qaz": ` + "`qux-quux`" + `
+ qax: qux
+
+ fiz: 4
+ faz: ` + "`fiz`" + `
+ // fuz
+ fuz: ` + "`qux-quux`" + ` // fuz
+
+ // biz
+ ` + "`biz`" + `: 5 // biz
+ buz: ` + "`biz`" + `
+ baz: ` + "`qux`" + `
}
`,
out: `package foo
-"foo": 3
-` + "`foo-bar`" + `: 2
-"baz": ` + "`foo-bar`" + `
+"foo": 3
+X1="foo-bar": 2
+"baz": X1
a: {
- qux: 3
- ` + "`qux-quux`" + `: qux
- "qaz": ` + "`qux-quux`" + `
+ // qux
+ X2="qux": 3 // qux line
+ // qux-quux
+ X3="qux-quux": X2
+ "qaz": X3
+ qax: X2
+
+ fiz: 4
+ faz: fiz
+ // fuz
+ fuz: X3 // fuz
+
+ // biz
+ biz: 5 // biz
+ buz: biz
+ baz: X2
}
`,
}, {
diff --git a/cue/ast/ident.go b/cue/ast/ident.go
index a626ba2..35d8838 100644
--- a/cue/ast/ident.go
+++ b/cue/ast/ident.go
@@ -32,8 +32,24 @@
return '0' <= ch && ch <= '9' || ch >= utf8.RuneSelf && unicode.IsDigit(ch)
}
+// IsValidIdent reports whether str is a valid identifier.
+func IsValidIdent(ident string) bool {
+ for i, r := range ident {
+ if isLetter(r) || r == '_' {
+ continue
+ }
+ if i > 0 && isDigit(r) {
+ continue
+ }
+ return false
+ }
+ return true
+}
+
// QuoteIdent quotes an identifier, if needed, and reports
// an error if the identifier is invalid.
+//
+// Deprecated: quoted identifiers are deprecated. Use aliases.
func QuoteIdent(ident string) (string, error) {
if ident != "" && ident[0] == '`' {
if _, err := strconv.Unquote(ident); err != nil {
@@ -66,6 +82,8 @@
// ParseIdent unquotes a possibly quoted identifier and validates
// if the result is valid.
+//
+// Deprecated: quoted identifiers are deprecated. Use aliases.
func ParseIdent(n *Ident) (string, error) {
ident := n.Name
if ident == "" {
diff --git a/cue/format/node.go b/cue/format/node.go
index e2572d6..c0a3d4c 100644
--- a/cue/format/node.go
+++ b/cue/format/node.go
@@ -384,6 +384,9 @@
f.before(l)
defer f.after(l)
switch n := l.(type) {
+ case *ast.Alias:
+ f.expr(n)
+
case *ast.Ident:
// Escape an identifier that has invalid characters. This may happen,
// if the AST is not generated by the parser.
