Handle foreach expressions in mk2rbc
Bug: 201700692
Test: go test
Change-Id: Ia23494a63567a1fe2d4bb797a2d4dd5925b3431d
diff --git a/mk2rbc/expr.go b/mk2rbc/expr.go
index 81b31c7..ca48bd9 100644
--- a/mk2rbc/expr.go
+++ b/mk2rbc/expr.go
@@ -31,6 +31,12 @@
// Emit the code to copy the expression, otherwise we will end up
// with source and target pointing to the same list.
emitListVarCopy(gctx *generationContext)
+ // Return the expression, calling the transformer func for
+ // every expression in the tree. If the transformer func returns non-nil,
+ // its result is used in place of the expression it was called with in the
+ // resulting expression. The resulting starlarkExpr will contain as many
+ // of the same objects from the original expression as possible.
+ transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr
}
func maybeString(expr starlarkExpr) (string, bool) {
@@ -62,6 +68,14 @@
s.emit(gctx)
}
+func (s *stringLiteralExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ if replacement := transformer(s); replacement != nil {
+ return replacement
+ } else {
+ return s
+ }
+}
+
// Integer literal
type intLiteralExpr struct {
literal int
@@ -85,6 +99,14 @@
s.emit(gctx)
}
+func (s *intLiteralExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ if replacement := transformer(s); replacement != nil {
+ return replacement
+ } else {
+ return s
+ }
+}
+
// Boolean literal
type boolLiteralExpr struct {
literal bool
@@ -110,6 +132,14 @@
b.emit(gctx)
}
+func (b *boolLiteralExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ if replacement := transformer(b); replacement != nil {
+ return replacement
+ } else {
+ return b
+ }
+}
+
// interpolateExpr represents Starlark's interpolation operator <string> % list
// we break <string> into a list of chunks, i.e., "first%second%third" % (X, Y)
// will have chunks = ["first", "second", "third"] and args = [X, Y]
@@ -190,6 +220,19 @@
xi.emit(gctx)
}
+func (xi *interpolateExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ argsCopy := make([]starlarkExpr, len(xi.args))
+ for i, arg := range xi.args {
+ argsCopy[i] = arg.transform(transformer)
+ }
+ xi.args = argsCopy
+ if replacement := transformer(xi); replacement != nil {
+ return replacement
+ } else {
+ return xi
+ }
+}
+
type variableRefExpr struct {
ref variable
isDefined bool
@@ -220,6 +263,14 @@
}
}
+func (v *variableRefExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ if replacement := transformer(v); replacement != nil {
+ return replacement
+ } else {
+ return v
+ }
+}
+
type toStringExpr struct {
expr starlarkExpr
}
@@ -265,6 +316,15 @@
s.emit(gctx)
}
+func (s *toStringExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ s.expr = s.expr.transform(transformer)
+ if replacement := transformer(s); replacement != nil {
+ return replacement
+ } else {
+ return s
+ }
+}
+
type notExpr struct {
expr starlarkExpr
}
@@ -291,6 +351,15 @@
n.emit(gctx)
}
+func (n *notExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ n.expr = n.expr.transform(transformer)
+ if replacement := transformer(n); replacement != nil {
+ return replacement
+ } else {
+ return n
+ }
+}
+
type eqExpr struct {
left, right starlarkExpr
isEq bool // if false, it's !=
@@ -360,6 +429,16 @@
eq.emit(gctx)
}
+func (eq *eqExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ eq.left = eq.left.transform(transformer)
+ eq.right = eq.right.transform(transformer)
+ if replacement := transformer(eq); replacement != nil {
+ return replacement
+ } else {
+ return eq
+ }
+}
+
// variableDefinedExpr corresponds to Make's ifdef VAR
type variableDefinedExpr struct {
v variable
@@ -388,6 +467,11 @@
v.emit(gctx)
}
+func (v *variableDefinedExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ // TODO: VariableDefinedExpr isn't really an expression?
+ return v
+}
+
type listExpr struct {
items []starlarkExpr
}
@@ -442,6 +526,19 @@
l.emit(gctx)
}
+func (l *listExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ itemsCopy := make([]starlarkExpr, len(l.items))
+ for i, item := range l.items {
+ itemsCopy[i] = item.transform(transformer)
+ }
+ l.items = itemsCopy
+ if replacement := transformer(l); replacement != nil {
+ return replacement
+ } else {
+ return l
+ }
+}
+
func newStringListExpr(items []string) *listExpr {
v := listExpr{}
for _, item := range items {
@@ -505,6 +602,19 @@
c.emit(gctx)
}
+func (c *concatExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ itemsCopy := make([]starlarkExpr, len(c.items))
+ for i, item := range c.items {
+ itemsCopy[i] = item.transform(transformer)
+ }
+ c.items = itemsCopy
+ if replacement := transformer(c); replacement != nil {
+ return replacement
+ } else {
+ return c
+ }
+}
+
// inExpr generates <expr> [not] in <list>
type inExpr struct {
expr starlarkExpr
@@ -543,23 +653,33 @@
i.emit(gctx)
}
+func (i *inExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ i.expr = i.expr.transform(transformer)
+ i.list = i.list.transform(transformer)
+ if replacement := transformer(i); replacement != nil {
+ return replacement
+ } else {
+ return i
+ }
+}
+
type indexExpr struct {
array starlarkExpr
index starlarkExpr
}
-func (ix indexExpr) emit(gctx *generationContext) {
+func (ix *indexExpr) emit(gctx *generationContext) {
ix.array.emit(gctx)
gctx.write("[")
ix.index.emit(gctx)
gctx.write("]")
}
-func (ix indexExpr) typ() starlarkType {
+func (ix *indexExpr) typ() starlarkType {
return starlarkTypeString
}
-func (ix indexExpr) eval(valueMap map[string]starlarkExpr) (res starlarkExpr, same bool) {
+func (ix *indexExpr) eval(valueMap map[string]starlarkExpr) (res starlarkExpr, same bool) {
newArray, isSameArray := ix.array.eval(valueMap)
newIndex, isSameIndex := ix.index.eval(valueMap)
if same = isSameArray && isSameIndex; same {
@@ -570,10 +690,20 @@
return
}
-func (ix indexExpr) emitListVarCopy(gctx *generationContext) {
+func (ix *indexExpr) emitListVarCopy(gctx *generationContext) {
ix.emit(gctx)
}
+func (ix *indexExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ ix.array = ix.array.transform(transformer)
+ ix.index = ix.index.transform(transformer)
+ if replacement := transformer(ix); replacement != nil {
+ return replacement
+ } else {
+ return ix
+ }
+}
+
type callExpr struct {
object starlarkExpr // nil if static call
name string
@@ -642,6 +772,21 @@
cx.emit(gctx)
}
+func (cx *callExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ if cx.object != nil {
+ cx.object = cx.object.transform(transformer)
+ }
+ argsCopy := make([]starlarkExpr, len(cx.args))
+ for i, arg := range cx.args {
+ argsCopy[i] = arg.transform(transformer)
+ }
+ if replacement := transformer(cx); replacement != nil {
+ return replacement
+ } else {
+ return cx
+ }
+}
+
type ifExpr struct {
condition starlarkExpr
ifTrue starlarkExpr
@@ -691,6 +836,92 @@
i.emit(gctx)
}
+func (i *ifExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ i.condition = i.condition.transform(transformer)
+ i.ifTrue = i.ifTrue.transform(transformer)
+ i.ifFalse = i.ifFalse.transform(transformer)
+ if replacement := transformer(i); replacement != nil {
+ return replacement
+ } else {
+ return i
+ }
+}
+
+type identifierExpr struct {
+ name string
+}
+
+func (i *identifierExpr) eval(valueMap map[string]starlarkExpr) (res starlarkExpr, same bool) {
+ return i, true
+}
+
+func (i *identifierExpr) emit(gctx *generationContext) {
+ gctx.write(i.name)
+}
+
+func (i *identifierExpr) typ() starlarkType {
+ return starlarkTypeUnknown
+}
+
+func (i *identifierExpr) emitListVarCopy(gctx *generationContext) {
+ i.emit(gctx)
+}
+
+func (i *identifierExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ if replacement := transformer(i); replacement != nil {
+ return replacement
+ } else {
+ return i
+ }
+}
+
+type foreachExpr struct {
+ varName string
+ list starlarkExpr
+ action starlarkExpr
+}
+
+func (f *foreachExpr) eval(valueMap map[string]starlarkExpr) (res starlarkExpr, same bool) {
+ list, listSame := f.list.eval(valueMap)
+ action, actionSame := f.action.eval(valueMap)
+ same = listSame && actionSame
+ if same {
+ return f, same
+ } else {
+ return &foreachExpr{
+ varName: f.varName,
+ list: list,
+ action: action,
+ }, same
+ }
+}
+
+func (f *foreachExpr) emit(gctx *generationContext) {
+ gctx.write("[")
+ f.action.emit(gctx)
+ gctx.write(" for " + f.varName + " in ")
+ f.list.emit(gctx)
+ gctx.write("]")
+}
+
+func (f *foreachExpr) typ() starlarkType {
+ return starlarkTypeList
+}
+
+func (f *foreachExpr) emitListVarCopy(gctx *generationContext) {
+ f.emit(gctx)
+}
+
+func (f *foreachExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ f.list = f.list.transform(transformer)
+ f.action = f.action.transform(transformer)
+ if replacement := transformer(f); replacement != nil {
+ return replacement
+ } else {
+ return f
+ }
+}
+
type badExpr struct {
errorLocation ErrorLocation
message string
@@ -714,6 +945,14 @@
panic("implement me")
}
+func (b *badExpr) transform(transformer func(expr starlarkExpr) starlarkExpr) starlarkExpr {
+ if replacement := transformer(b); replacement != nil {
+ return replacement
+ } else {
+ return b
+ }
+}
+
func maybeConvertToStringList(expr starlarkExpr) starlarkExpr {
if xString, ok := expr.(*stringLiteralExpr); ok {
return newStringListExpr(strings.Fields(xString.literal))