Convert $(words) to Starlark

Bug: 226974242
Test: go test
Change-Id: I8ab5943306586c6a993df470e7a2894dd7ff1619

mk2rbc/mk2rbc.go

@@ -116,6 +116,7 @@ var knownFunctions = map[string]interface {
 	"subst":    &substCallParser{fname: "subst"},
 	"warning":  &makeControlFuncParser{name: baseName + ".mkwarning"},
 	"word":     &wordCallParser{},
+	"words":    &wordsCallParser{},
 	"wildcard": &simpleCallParser{name: baseName + ".expand_wildcard", returnType: starlarkTypeList},
 }
 
@@ -1637,9 +1638,11 @@ func (p *wordCallParser) parse(ctx *parseContext, node mkparser.Node, args *mkpa
 	if len(words) != 2 {
 		return ctx.newBadExpr(node, "word function should have 2 arguments")
 	}
-	var index uint64 = 0
+	var index = 0
 	if words[0].Const() {
-		index, _ = strconv.ParseUint(strings.TrimSpace(words[0].Strings[0]), 10, 64)
+		if i, err := strconv.Atoi(strings.TrimSpace(words[0].Strings[0])); err == nil {
+			index = i
+		}
 	}
 	if index < 1 {
 		return ctx.newBadExpr(node, "word index should be constant positive integer")
@@ -1647,13 +1650,40 @@ func (p *wordCallParser) parse(ctx *parseContext, node mkparser.Node, args *mkpa
 	words[1].TrimLeftSpaces()
 	words[1].TrimRightSpaces()
 	array := ctx.parseMakeString(node, words[1])
-	if xBad, ok := array.(*badExpr); ok {
+	if bad, ok := array.(*badExpr); ok {
-		return xBad
+		return bad
 	}
 	if array.typ() != starlarkTypeList {
-		array = &callExpr{object: array, name: "split", returnType: starlarkTypeList}
+		array = &callExpr{
+			name:       baseName + ".words",
+			args:       []starlarkExpr{array},
+			returnType: starlarkTypeList,
+		}
+	}
+	return &indexExpr{array, &intLiteralExpr{index - 1}}
+}
+
+type wordsCallParser struct{}
+
+func (p *wordsCallParser) parse(ctx *parseContext, node mkparser.Node, args *mkparser.MakeString) starlarkExpr {
+	args.TrimLeftSpaces()
+	args.TrimRightSpaces()
+	array := ctx.parseMakeString(node, args)
+	if bad, ok := array.(*badExpr); ok {
+		return bad
+	}
+	if array.typ() != starlarkTypeList {
+		array = &callExpr{
+			name:       baseName + ".words",
+			args:       []starlarkExpr{array},
+			returnType: starlarkTypeList,
+		}
+	}
+	return &callExpr{
+		name:       "len",
+		args:       []starlarkExpr{array},
+		returnType: starlarkTypeInt,
 	}
-	return &indexExpr{array, &intLiteralExpr{int(index - 1)}}
 }
 
 type firstOrLastwordCallParser struct {

mk2rbc/mk2rbc_test.go

@@ -808,6 +808,10 @@ def init(g, handle):
 PRODUCT_COPY_FILES := $(addprefix pfx-,a b c)
 PRODUCT_COPY_FILES := $(addsuffix .sff, a b c)
 PRODUCT_NAME := $(word 1, $(subst ., ,$(TARGET_BOARD_PLATFORM)))
+ifeq (1,$(words $(SOME_UNKNOWN_VARIABLE)))
+endif
+ifeq ($(words $(SOME_OTHER_VARIABLE)),$(SOME_INT_VARIABLE))
+endif
 $(info $(patsubst %.pub,$(PRODUCT_NAME)%,$(PRODUCT_ADB_KEYS)))
 $(info $$(dir foo/bar): $(dir foo/bar))
 $(info $(firstword $(PRODUCT_COPY_FILES)))
@@ -830,7 +834,11 @@ def init(g, handle):
   cfg = rblf.cfg(handle)
   cfg["PRODUCT_COPY_FILES"] = rblf.addprefix("pfx-", "a b c")
   cfg["PRODUCT_COPY_FILES"] = rblf.addsuffix(".sff", "a b c")
-  cfg["PRODUCT_NAME"] = ((g.get("TARGET_BOARD_PLATFORM", "")).replace(".", " ")).split()[0]
+  cfg["PRODUCT_NAME"] = rblf.words((g.get("TARGET_BOARD_PLATFORM", "")).replace(".", " "))[0]
+  if len(rblf.words(g.get("SOME_UNKNOWN_VARIABLE", ""))) == 1:
+    pass
+  if ("%d" % (len(rblf.words(g.get("SOME_OTHER_VARIABLE", ""))))) == g.get("SOME_INT_VARIABLE", ""):
+    pass
   rblf.mkinfo("product.mk", rblf.mkpatsubst("%.pub", "%s%%" % cfg["PRODUCT_NAME"], g.get("PRODUCT_ADB_KEYS", "")))
   rblf.mkinfo("product.mk", "$(dir foo/bar): %s" % rblf.dir("foo/bar"))
   rblf.mkinfo("product.mk", cfg["PRODUCT_COPY_FILES"][0])