Disallow unparenthesized for in calls with multiple arguments

Author: msimacek

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/ErrorMessages.java

@@ -216,6 +216,7 @@ public abstract class ErrorMessages {
     public static final String FUNC_CONSTRUCTION_NOT_SUPPORTED = "function construction not supported for (%p, %p, %p, %p, %p, %p)";
     public static final String FUNC_TAKES_AT_LEAST_D_ARGS = "function takes at least %d arguments (%d given)";
     public static final String FUNC_TAKES_EXACTLY_D_ARGS = "function takes exaclty %d arguments (%d given)";
+    public static final String GENERATOR_EXPR_MUST_BE_PARENTHESIZED = "Generator expression must be parenthesized";
     public static final String GENERATOR_IGNORED_EXIT = "generator ignored GeneratorExit";
     public static final String GENERATOR_RAISED_STOPITER = "generator raised StopIteration";
     public static final String GENERATOR_ALREADY_EXECUTING = "generator already executing";

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/parser/antlr/Python3.g4

@@ -1622,7 +1622,7 @@ argument [ArgListBuilder args] returns [SSTNode result]
                 }
 		test comp_for[$test.result, null, PythonBuiltinClassType.PGenerator, 0]
                 {
-                    args.addArg($comp_for.result);
+                    args.addNakedForComp($comp_for.result);
                    scopeEnvironment.popScope();
                 }
 	|

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/parser/sst/ArgListBuilder.java

@@ -61,6 +61,7 @@ public final class ArgListBuilder {
     private List<String> nameArgNames;
     private List<SSTNode> starArg;
     private List<SSTNode> kwArg;
+    private SSTNode nakedForComp;
 
     public ArgListBuilder() {
         // default
@@ -188,4 +189,16 @@ public ExpressionNode getStarArgs(SSTreeVisitor<PNode> visitor) {
         return result;
     }
 
+    public boolean hasNakedForComp() {
+        return nakedForComp != null;
+    }
+
+    public SSTNode getNakedForComp() {
+        return nakedForComp;
+    }
+
+    public void addNakedForComp(SSTNode node) {
+        this.nakedForComp = node;
+        addArg(node);
+    }
 }

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/parser/sst/FactorySSTVisitor.java

@@ -347,6 +347,10 @@ public PNode visit(CallSSTNode node) {
         ExpressionNode target = (ExpressionNode) node.target.accept(this);
 
         ArgListBuilder argBuilder = node.parameters;
+        if (argBuilder.hasNakedForComp() && argBuilder.getArgs().length != 1) {
+            SSTNode forComp = argBuilder.getNakedForComp();
+            throw errors.raiseInvalidSyntax(source, createSourceSection(forComp.getStartOffset(), forComp.getEndOffset()), ErrorMessages.GENERATOR_EXPR_MUST_BE_PARENTHESIZED);
+        }
         ExpressionNode callNode = PythonCallNode.create(target, argBuilder.getArgs(this), argBuilder.getNameArgs(this), argBuilder.getStarArgs(this), argBuilder.getKwArgs(this));
         callNode.assignSourceSection(createSourceSection(node.startOffset, node.endOffset));
         return callNode;
@@ -457,6 +461,10 @@ public PNode visit(ClassSSTNode node) {
         ExpressionNode starArg = null;
         ExpressionNode kwArg = null;
         if (node.baseClasses != null) {
+            if (node.baseClasses.hasNakedForComp()) {
+                SSTNode forComp = node.baseClasses.getNakedForComp();
+                throw errors.raiseInvalidSyntax(source, createSourceSection(forComp.getStartOffset(), forComp.getEndOffset()));
+            }
             ExpressionNode[] sstArgs = node.baseClasses.getArgs(this);
             args = new ExpressionNode[sstArgs.length + 2];
             for (int i = 0; i < sstArgs.length; i++) {