Forbid **kwargs and *args in BUILD files.
Rationale: it makes BUILD files less declarative and makes harder to do
automated changes on BUILD files. It is however still allowed in .bzl
files.
--
MOS_MIGRATED_REVID=94577442
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/Parser.java b/src/main/java/com/google/devtools/build/lib/syntax/Parser.java
index ae267e5..67e13e5 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/Parser.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/Parser.java
@@ -407,16 +407,30 @@
// arg ::= IDENTIFIER '=' nontupleexpr
// | expr
+ // | *args (only in Skylark mode)
+ // | **kwargs (only in Skylark mode)
+ // To keep BUILD files declarative and easy to process, *args and **kwargs
+ // arguments are allowed only in Skylark mode.
private Argument.Passed parseFuncallArgument() {
final int start = token.left;
// parse **expr
if (token.kind == TokenKind.STAR_STAR) {
+ if (!skylarkMode) {
+ reportError(
+ lexer.createLocation(token.left, token.right),
+ "**kwargs arguments are not allowed in BUILD files");
+ }
nextToken();
Expression expr = parseNonTupleExpression();
return setLocation(new Argument.StarStar(expr), start, expr);
}
// parse *expr
if (token.kind == TokenKind.STAR) {
+ if (!skylarkMode) {
+ reportError(
+ lexer.createLocation(token.left, token.right),
+ "*args arguments are not allowed in BUILD files");
+ }
nextToken();
Expression expr = parseNonTupleExpression();
return setLocation(new Argument.Star(expr), start, expr);
diff --git a/src/test/java/com/google/devtools/build/lib/syntax/ParserTest.java b/src/test/java/com/google/devtools/build/lib/syntax/ParserTest.java
index ef1b9f9..5f33718 100644
--- a/src/test/java/com/google/devtools/build/lib/syntax/ParserTest.java
+++ b/src/test/java/com/google/devtools/build/lib/syntax/ParserTest.java
@@ -1036,6 +1036,20 @@
}
@Test
+ public void testKwargsForbidden() throws Exception {
+ setFailFast(false);
+ parseFile("func(**dict)");
+ assertContainsEvent("**kwargs arguments are not allowed in BUILD files");
+ }
+
+ @Test
+ public void testArgsForbidden() throws Exception {
+ setFailFast(false);
+ parseFile("func(*array)");
+ assertContainsEvent("*args arguments are not allowed in BUILD files");
+ }
+
+ @Test
public void testOptionalArgBeforeMandatoryArgInFuncDef() throws Exception {
setFailFast(false);
parseFileForSkylark("def func(a, b = 'a', c):\n return 0\n");
