Skylark: New error message in the lexer when an unsupported Python keyword is used.

--
MOS_MIGRATED_REVID=88930203

2 files changed, 23 insertions, 9 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/Lexer.java b/src/main/java/com/google/devtools/build/lib/syntax/Lexer.java
index 7531b84ae3..0b96c00060 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/Lexer.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/Lexer.java
@@ -441,28 +441,46 @@ public final class Lexer {
   private static final Map<String, TokenKind> keywordMap = new HashMap<>();
 
   static {
+    // We insert TokenKind.ILLEGAL for every unsupported Python keyword.
+    // List of keywords come from "keyword.kwlist" in Python 3.4.0.
     keywordMap.put("and", TokenKind.AND);
     keywordMap.put("as", TokenKind.AS);
-    keywordMap.put("class", TokenKind.CLASS); // reserved for future expansion
+    keywordMap.put("assert", TokenKind.ILLEGAL);
+    keywordMap.put("break", TokenKind.ILLEGAL);
+    keywordMap.put("class", TokenKind.CLASS);
+    keywordMap.put("continue", TokenKind.ILLEGAL);
     keywordMap.put("def", TokenKind.DEF);
+    keywordMap.put("del", TokenKind.ILLEGAL);
     keywordMap.put("elif", TokenKind.ELIF);
     keywordMap.put("else", TokenKind.ELSE);
-    keywordMap.put("except", TokenKind.EXCEPT);
-    keywordMap.put("finally", TokenKind.FINALLY);
+    keywordMap.put("except", TokenKind.ILLEGAL);
+    keywordMap.put("finally", TokenKind.ILLEGAL);
     keywordMap.put("for", TokenKind.FOR);
-    keywordMap.put("from", TokenKind.FROM);
+    keywordMap.put("from", TokenKind.ILLEGAL);
+    keywordMap.put("global", TokenKind.ILLEGAL);
     keywordMap.put("if", TokenKind.IF);
-    keywordMap.put("import", TokenKind.IMPORT);
+    keywordMap.put("import", TokenKind.ILLEGAL);
     keywordMap.put("in", TokenKind.IN);
+    keywordMap.put("is", TokenKind.ILLEGAL);
+    keywordMap.put("lambda", TokenKind.ILLEGAL);
+    keywordMap.put("nonlocal", TokenKind.ILLEGAL);
     keywordMap.put("not", TokenKind.NOT);
     keywordMap.put("or", TokenKind.OR);
     keywordMap.put("pass", TokenKind.PASS);
+    keywordMap.put("raise", TokenKind.ILLEGAL);
     keywordMap.put("return", TokenKind.RETURN);
     keywordMap.put("try", TokenKind.TRY);
+    keywordMap.put("while", TokenKind.ILLEGAL);
+    keywordMap.put("with", TokenKind.ILLEGAL);
+    keywordMap.put("yield", TokenKind.ILLEGAL);
   }
 
   private TokenKind getTokenKindForIdentfier(String id) {
     TokenKind kind = keywordMap.get(id);
+    if (kind == TokenKind.ILLEGAL) {
+      error("The Python keyword '" + id + "' is not supported");
+      return TokenKind.IDENTIFIER;
+    }
     return kind == null ? TokenKind.IDENTIFIER : kind;
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/TokenKind.java b/src/main/java/com/google/devtools/build/lib/syntax/TokenKind.java
index e7e92b4260..fa73a09852 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/TokenKind.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/TokenKind.java
@@ -32,16 +32,12 @@ public enum TokenKind {
   EOF("EOF"),
   EQUALS("="),
   EQUALS_EQUALS("=="),
-  EXCEPT("except"),
-  FINALLY("finally"),
   FOR("for"),
-  FROM("from"),
   GREATER(">"),
   GREATER_EQUALS(">="),
   IDENTIFIER("identifier"),
   IF("if"),
   ILLEGAL("illegal character"),
-  IMPORT("import"),
   IN("in"),
   INDENT("indent"),
   INT("integer"),