add length message

Author: timfel

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/PythonAbstractObject.java

@@ -590,6 +590,36 @@ public boolean isSequence(@Shared("thisObject") @Cached GetLazyClassNode getClas
         return pythonTypeLibrary.isSequenceType(getClassNode.execute(this));
     }
 
+    @ExportMessage
+    public int lengthWithState(ThreadState state,
+                    @Exclusive @Cached("createBinaryProfile()") ConditionProfile gotState,
+                    @Exclusive @Cached("createBinaryProfile()") ConditionProfile hasLen,
+                    @Exclusive @Cached("createBinaryProfile()") ConditionProfile ltZero,
+                    @Exclusive @Cached LookupInheritedAttributeNode.Dynamic getLenNode,
+                    @Exclusive @Cached CallNode callNode,
+                    @Exclusive @Cached PRaiseNode raiseNode,
+                    @Exclusive @CachedLibrary(limit = "1") PythonObjectLibrary lib) {
+        Object lenFunc = getLenNode.execute(this, SpecialMethodNames.__LEN__);
+        if (hasLen.profile(lenFunc != PNone.NO_VALUE)) {
+            Object lenResult;
+            int len;
+            if (gotState.profile(state == null)) {
+                lenResult = callNode.execute(lenFunc, this);
+                len = lib.asSize(lenResult);
+            } else {
+                lenResult = callNode.execute(PArguments.frameForCall(state), lenFunc, this);
+                len = lib.asSizeWithState(lenResult, state);
+            }
+            if (ltZero.profile(len < 0)) {
+                throw raiseNode.raise(PythonBuiltinClassType.ValueError, "__len__() should return >= 0");
+            } else {
+                return len;
+            }
+        } else {
+            throw raiseNode.raiseHasNoLength(this);
+        }
+    }
+
     @ExportMessage
     public boolean isMapping(@Shared("thisObject") @Cached GetLazyClassNode getClassNode,
                     @CachedLibrary(limit = "1") PythonObjectLibrary pythonTypeLibrary) {

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/object/DefaultPythonObjectExports.java

@@ -92,7 +92,7 @@ static Object asIndex(Object receiver,
     @ExportMessage
     static int asSize(Object receiver, LazyPythonClass type,
                     @Shared("raiseNode") @Cached PRaiseNode raise,
-                    @CachedLibrary("receiver") InteropLibrary interopLib) {
+                    @CachedLibrary(limit = "2") InteropLibrary interopLib) {
         Object index = asIndex(receiver, raise, interopLib);
         if (interopLib.fitsInInt(index)) {
             try {
@@ -116,4 +116,26 @@ static LazyPythonClass getLazyPythonClass(@SuppressWarnings("unused") Object val
     static long hash(Object receiver) {
         return receiver.hashCode();
     }
+
+    @ExportMessage
+    static int length(Object receiver,
+                    @Shared("raiseNode") @Cached PRaiseNode raise,
+                    @CachedLibrary("receiver") InteropLibrary interopLib) {
+        if (interopLib.hasArrayElements(receiver)) {
+            long sz;
+            try {
+                sz = interopLib.getArraySize(receiver);
+            } catch (UnsupportedMessageException e) {
+                CompilerDirectives.transferToInterpreter();
+                throw new IllegalStateException(e);
+            }
+            if (sz == (int) sz) {
+                return (int) sz;
+            } else {
+                throw raise.raiseNumberTooLarge(PythonBuiltinClassType.OverflowError, sz);
+            }
+        } else {
+            throw raise.raiseHasNoLength(receiver);
+        }
+    }
 }

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/object/DefaultPythonStringExports.java

@@ -84,4 +84,9 @@ static byte[] getBufferBytes(String str) {
     static long hash(String self) {
         return self.hashCode();
     }
+
+    @ExportMessage
+    static int length(String self) {
+        return self.length();
+    }
 }

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/object/PythonObjectLibrary.java

@@ -315,6 +315,31 @@ public boolean isSequence(Object receiver) {
         return false;
     }
 
+
+    /**
+     * Implements the logic from {@code PyObject_Size} (to which {@code
+     * PySequence_Length} is an alias). The logic which is to try a) {@code
+     * sq_length} and b) {@code mp_length}. Each of these can also be reached
+     * via {@code PySequence_Length} or {@code PyMapping_Length}, respectively.
+     *
+     * The implementation for {@code slot_sq_length} is to call {@code __len__}
+     * and then to convert it to an index and a size, making sure it's
+     * >=0. {@code slot_mp_length} is just an alias for that slot.
+     */
+    public int lengthWithState(Object receiver, ThreadState state) {
+        if (state == null) {
+            throw PRaiseNode.getUncached().raiseHasNoLength(receiver);
+        }
+        return length(receiver);
+    }
+
+    /**
+     * @see #lengthWithState
+     */
+    public int length(Object receiver) {
+        return lengthWithState(receiver, null);
+    }
+
     /**
      * Checks whether the receiver is a Python mapping. As described in the
      * <a href="https://docs.python.org/3/reference/datamodel.html">Python Data Model</a> and

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

@@ -84,6 +84,10 @@ public final PException raiseNumberTooLarge(LazyPythonClass type, Object result)
         return execute(type, PNone.NO_VALUE, "cannot fit '%p' into an index-sized integer", new Object[]{result});
     }
 
+    public final PException raiseHasNoLength(Object result) {
+        return raise(PythonBuiltinClassType.TypeError, "object of type '%p' has no len()", result);
+    }
+
     public final PException raiseIntegerInterpretationError(Object result) {
         return raise(PythonBuiltinClassType.TypeError, "'%p' object cannot be interpreted as an integer", result);
     }