[GR-40604] Implement limited sys._current_frames

PullRequest: graalpython/2413

Author: msimacek

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/SysModuleBuiltins.java

@@ -161,6 +161,7 @@
 import com.oracle.graal.python.builtins.modules.io.TextIOWrapperNodes.TextIOWrapperInitNode;
 import com.oracle.graal.python.builtins.modules.io.TextIOWrapperNodesFactory.TextIOWrapperInitNodeGen;
 import com.oracle.graal.python.builtins.objects.PNone;
+import com.oracle.graal.python.builtins.objects.common.HashingStorageLibrary;
 import com.oracle.graal.python.builtins.objects.common.SequenceStorageNodes;
 import com.oracle.graal.python.builtins.objects.dict.PDict;
 import com.oracle.graal.python.builtins.objects.exception.PBaseException;
@@ -234,6 +235,7 @@
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.frame.MaterializedFrame;
 import com.oracle.truffle.api.frame.VirtualFrame;
+import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.Node;
 import com.oracle.truffle.api.profiles.ConditionProfile;
 import com.oracle.truffle.api.strings.TruffleString;
@@ -789,6 +791,26 @@ private PException raiseCallStackDepth() {
         }
     }
 
+    @Builtin(name = "_current_frames")
+    @GenerateNodeFactory
+    abstract static class CurrentFrames extends PythonBuiltinNode {
+        @Specialization
+        Object currentFrames(VirtualFrame frame,
+                        @Cached AuditNode auditNode,
+                        @Cached WarningsModuleBuiltins.WarnNode warnNode,
+                        @Cached ReadCallerFrameNode readCallerFrameNode,
+                        @CachedLibrary(limit = "1") HashingStorageLibrary hlib) {
+            auditNode.audit("sys._current_frames");
+            if (!getLanguage().singleThreadedAssumption.isValid()) {
+                warnNode.warn(frame, RuntimeWarning, ErrorMessages.WARN_CURRENT_FRAMES_MULTITHREADED);
+            }
+            PFrame currentFrame = readCallerFrameNode.executeWith(frame, 0);
+            PDict result = factory().createDict();
+            result.setDictStorage(hlib.setItem(result.getDictStorage(), Thread.currentThread().getId(), currentFrame));
+            return result;
+        }
+    }
+
     @Builtin(name = "getfilesystemencoding", minNumOfPositionalArgs = 0)
     @GenerateNodeFactory
     public abstract static class GetFileSystemEncodingNode extends PythonBuiltinNode {

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

@@ -1342,6 +1342,8 @@ public abstract class ErrorMessages {
     public static final TruffleString WARN_IGNORE_UNIMPORTABLE_BREAKPOINT_S = tsLiteral("Ignoring unimportable $PYTHONBREAKPOINT: \"%s\"");
     public static final TruffleString WARN_DEPRECTATED_SYS_CHECKINTERVAL = tsLiteral("sys.getcheckinterval() and sys.setcheckinterval() " +
                     "are deprecated.  Use sys.getswitchinterval() instead.");
+    public static final TruffleString WARN_CURRENT_FRAMES_MULTITHREADED = tsLiteral(
+                    "GraalPy doesn't support obtaining frames of other threads. That means python debuggers can only see the currently stopped thread");
 
     // error messages from parsing
     public static final TruffleString ERROR_MESSAGE_EMPTY_EXPRESSION = tsLiteral("f-string: empty expression not allowed");