php2go/normalisealts.go

102 lines
2.7 KiB
Go

package main
import (
"fmt"
//"io/ioutil"
"github.com/z7zmey/php-parser/node"
"github.com/z7zmey/php-parser/node/stmt"
"github.com/z7zmey/php-parser/walker"
)
type normaliseAltsPass struct {
}
func (np *normaliseAltsPass) transformNonRecursive(n node.Node) (node.Node, bool) {
switch n := n.(type) {
case *stmt.AltIf:
// Build replacement node
ifStmt := stmt.NewIf(n.Cond, n.Stmt, n.ElseIf, n.Else)
ifStmt.FreeFloating = n.FreeFloating
ifStmt.Position = n.Position
// ifStmt has no .Attributes prop
return ifStmt, true
case *stmt.AltElse:
elseStmt := stmt.NewElse(n.Stmt)
elseStmt.FreeFloating = n.FreeFloating
elseStmt.Position = n.Position
return elseStmt, true
case *stmt.AltElseIf:
elifStmt := stmt.NewElseIf(n.Cond, n.Stmt)
elifStmt.FreeFloating = n.FreeFloating
elifStmt.Position = n.Position
return elifStmt, true
default:
return n, false // no change
}
}
func (np *normaliseAltsPass) walkMutateArray(stmts []node.Node) {
for i, _ := range stmts {
np.walkMutate(&stmts[i])
}
}
func (np *normaliseAltsPass) walkMutate(child *node.Node) {
v2, didChange := np.transformNonRecursive(*child)
if didChange {
v2.Walk(np)
*child = v2
} else {
(*child).Walk(np)
}
}
func (np *normaliseAltsPass) EnterNode(w walker.Walkable) bool {
n, ok := w.(node.Node)
if !ok {
panic(fmt.Errorf("Tried to walk non-node '%t'", w))
}
// We need to override the .Walk() behaviour for all possible *parents*
// of affected nodes. This is because the .Walk() interface does not give
// us any opportunity to override single elements by the time we get there
// Our custom Walk() implementation is not firing all EnterChildList/LeaveNode
// visitors - but - that's fine since they're all noops anyway
switch n := n.(type) {
case *stmt.StmtList:
np.walkMutateArray(n.Stmts) // mutate slice in place
return false // Signal not to use upstream .Walk() implementation
case *node.Root:
np.walkMutateArray(n.Stmts) // mutate slice in place
return false // Signal not to use upstream .Walk() implementation
case *stmt.AltIf:
panic("altif")
np.walkMutate(&n.Cond)
np.walkMutateArray(n.ElseIf)
np.walkMutate(&n.Else)
return false
default:
// No normalisation needed for this node type
// Recurse deeper
return true
}
}
func (np *normaliseAltsPass) LeaveNode(w walker.Walkable) {}
func (np *normaliseAltsPass) EnterChildNode(key string, w walker.Walkable) {}
func (np *normaliseAltsPass) LeaveChildNode(key string, w walker.Walkable) {}
func (np *normaliseAltsPass) EnterChildList(key string, w walker.Walkable) {}
func (np *normaliseAltsPass) LeaveChildList(key string, w walker.Walkable) {}
var _ walker.Visitor = &normaliseAltsPass{} // interface assertion