[GR-18308] allow walking not-yet-classloaded java packages during import

PullRequest: graalpython/658

Author: timfel

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

@@ -61,6 +61,7 @@
 import static com.oracle.graal.python.nodes.BuiltinNames.__BUILTIN__;
 import static com.oracle.graal.python.nodes.BuiltinNames.__DEBUG__;
 import static com.oracle.graal.python.nodes.BuiltinNames.__DUMP_TRUFFLE_AST__;
+import static com.oracle.graal.python.nodes.BuiltinNames.__JYTHON_CURRENT_IMPORT__;
 import static com.oracle.graal.python.nodes.HiddenAttributes.ID_KEY;
 import static com.oracle.graal.python.nodes.SpecialAttributeNames.__NAME__;
 import static com.oracle.graal.python.nodes.SpecialMethodNames.__INSTANCECHECK__;
@@ -1881,6 +1882,15 @@ protected static boolean isFunction(Object callee) {
         }
     }
 
+    @Builtin(name = __JYTHON_CURRENT_IMPORT__, minNumOfPositionalArgs = 0)
+    @GenerateNodeFactory
+    public abstract static class CurrentImport extends PythonBuiltinNode {
+        @Specialization
+        String doIt() {
+            return getContext().getCurrentImport();
+        }
+    }
+
     @Builtin(name = "input", parameterNames = {"prompt"})
     @GenerateNodeFactory
     abstract static class InputNode extends PythonUnaryBuiltinNode {

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

@@ -135,4 +135,5 @@ public abstract class BuiltinNames {
     // truffle specific builtins
     public static final String __BUILTIN__ = "__builtin__";
     public static final String __DUMP_TRUFFLE_AST__ = "__dump_truffle_ast__";
+    public static final String __JYTHON_CURRENT_IMPORT__ = "__jython_current_import__";
 }

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/statement/AbstractImportNode.java

@@ -54,6 +54,7 @@
 import com.oracle.graal.python.nodes.object.GetDictNode;
 import com.oracle.graal.python.nodes.util.ExceptionStateNodes.PassCaughtExceptionNode;
 import com.oracle.graal.python.runtime.PythonContext;
+import com.oracle.graal.python.runtime.PythonOptions;
 import com.oracle.graal.python.runtime.object.PythonObjectFactory;
 import com.oracle.truffle.api.CompilerDirectives;
 import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
@@ -69,6 +70,7 @@ public abstract class AbstractImportNode extends StatementNode {
     @Child private CallNode callNode;
     @Child private GetDictNode getDictNode;
     @Child private PassCaughtExceptionNode passExceptionNode;
+    @CompilationFinal private Boolean emulateJython;
 
     public AbstractImportNode() {
         super();
@@ -122,7 +124,20 @@ protected Object importModule(VirtualFrame frame, String name, Object globals, S
                 return builtinModule;
             }
         }
-        return __import__(frame, name, globals, fromList, level);
+        if (emulateJython()) {
+            if (fromList.length > 0) {
+                getContext().pushCurrentImport(name + "." + fromList[0]);
+            } else {
+                getContext().pushCurrentImport(name);
+            }
+        }
+        try {
+            return __import__(frame, name, globals, fromList, level);
+        } finally {
+            if (emulateJython()) {
+                getContext().popCurrentImport();
+            }
+        }
     }
 
     Object __import__(VirtualFrame frame, String name, Object globals, String[] fromList, int level) {
@@ -138,6 +153,14 @@ Object __import__(VirtualFrame frame, String name, Object globals, String[] from
         });
     }
 
+    private boolean emulateJython() {
+        if (emulateJython == null) {
+            CompilerDirectives.transferToInterpreterAndInvalidate();
+            emulateJython = PythonOptions.getFlag(getContext(), PythonOptions.EmulateJython);
+        }
+        return emulateJython;
+    }
+
     @Override
     public boolean hasTag(Class<? extends Tag> tag) {
         return tag == StandardTags.CallTag.class || super.hasTag(tag);

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/PythonContext.java

@@ -36,6 +36,7 @@
 import java.io.OutputStream;
 import java.nio.file.LinkOption;
 import java.text.MessageFormat;
+import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -142,6 +143,10 @@ public final class PythonContext {
     private final PosixResources resources;
     private final AsyncHandler handler;
 
+    // A thread-local to store the full path to the currently active import statement, for Jython
+    // compat
+    private final ThreadLocal<ArrayDeque<String>> currentImport = new ThreadLocal<>();
+
     public PythonContext(PythonLanguage language, TruffleLanguage.Env env, PythonCore core) {
         this.language = language;
         this.core = core;
@@ -721,4 +726,30 @@ public boolean isPyFileInLanguageHome(TruffleFile path) {
         PythonLanguage.getLogger().log(Level.FINE, () -> "Cannot access file " + path + " because there is no language home.");
         return false;
     }
+
+    @TruffleBoundary
+    public String getCurrentImport() {
+        ArrayDeque<String> ci = currentImport.get();
+        if (ci == null || ci.isEmpty()) {
+            return "";
+        } else {
+            return ci.peek();
+        }
+    }
+
+    @TruffleBoundary
+    public void pushCurrentImport(String object) {
+        ArrayDeque<String> ci = currentImport.get();
+        if (ci == null) {
+            ci = new ArrayDeque<>();
+            currentImport.set(ci);
+        }
+        ci.push(object);
+    }
+
+    @TruffleBoundary
+    public void popCurrentImport() {
+        assert currentImport.get() != null && currentImport.get().peek() != null : "invalid popCurrentImport without push";
+        currentImport.get().pop();
+    }
 }

graalpython/lib-graalpython/java.py

@@ -130,6 +130,16 @@ class JavaImportFinder:
     if sys.graal_python_jython_emulation_enabled:
         @staticmethod
         def find_spec(fullname, path, target=None):
+            # Because of how Jython allows you to import classes that have not
+            # been loaded, yet, we need attempt to load types with the full
+            # string. This will ensure that if there is such a Java class, its
+            # package will have been initialized and thus the is_java_package
+            # check below will work
+            try:
+                type(__jython_current_import__())
+            except KeyError:
+                pass
+            # continue normally with import
             if JavaPackageLoader.is_java_package(fullname):
                 return _frozen_importlib.ModuleSpec(fullname, JavaPackageLoader, is_package=True)
             else:
@@ -151,3 +161,8 @@ def find_spec(fullname, path, target=None):
 sys.meta_path.append(JavaImportFinder)
 if sys.graal_python_jython_emulation_enabled:
     __getattr__ = JavaPackageLoader._make_getattr("java")
+else:
+    # remove __jython_current_import__ function from builtins module
+    import builtins
+    del builtins.__jython_current_import__
+    del builtins

mx.graalpython/mx_graalpython.py

@@ -53,7 +53,7 @@
 # compatibility between Python versions
 PY3 = sys.version_info[0] == 3
 if PY3:
-    raw_input = input
+    raw_input = input # pylint: disable=redefined-builtin;
 
 
 def _get_core_home():