Better support for "interactive" statements

ie what you create either on the repl (where we were close) or
with `exec compile(foo, bar, "single")` (where we were not so close).

With these changes, doctest seems to mostly be working.

src/analysis/type_analysis.cpp

@@ -381,6 +381,7 @@ private:
             case AST_LangPrimitive::NONE:
             case AST_LangPrimitive::SET_EXC_INFO:
             case AST_LangPrimitive::UNCACHE_EXC_INFO:
+            case AST_LangPrimitive::PRINT_EXPR:
                 return NONE;
             case AST_LangPrimitive::HASNEXT:
             case AST_LangPrimitive::NONZERO:

src/codegen/ast_interpreter.cpp

@@ -875,6 +875,11 @@ Value ASTInterpreter::visit_langPrimitive(AST_LangPrimitive* node) {
         assert(node->args.size() == 1);
         Value obj = visit_expr(node->args[0]);
         v = Value(boxBool(hasnext(obj.o)), jit ? jit->emitHasnext(obj) : NULL);
+    } else if (node->opcode == AST_LangPrimitive::PRINT_EXPR) {
+        abortJITing();
+        Value obj = visit_expr(node->args[0]);
+        printExprHelper(obj.o);
+        v = getNone();
     } else
         RELEASE_ASSERT(0, "unknown opcode %d", node->opcode);
     return v;
@@ -1870,6 +1875,13 @@ Box* astInterpretDeopt(CLFunction* clfunc, AST_expr* after_expr, AST_stmt* enclo
     return v ? v : None;
 }
 
+extern "C" void printExprHelper(Box* obj) {
+    Box* displayhook = PySys_GetObject("displayhook");
+    if (!displayhook)
+        raiseExcHelper(RuntimeError, "lost sys.displayhook");
+    runtimeCall(displayhook, ArgPassSpec(1), obj, 0, 0, 0, 0);
+}
+
 static ASTInterpreter* getInterpreterFromFramePtr(void* frame_ptr) {
     // This offsets have to match the layout inside executeInnerAndSetupFrame
     ASTInterpreter** ptr = (ASTInterpreter**)(((uint8_t*)frame_ptr) - 8);

src/codegen/ast_interpreter.h

@@ -83,6 +83,9 @@ FrameInfo* getFrameInfoForInterpretedFrame(void* frame_ptr);
 BoxedClosure* passedClosureForInterpretedFrame(void* frame_ptr);
 
 BoxedDict* localsForInterpretedFrame(void* frame_ptr, bool only_user_visible);
+
+// Executes the equivalent of CPython's PRINT_EXPR opcode (call sys.displayhook)
+extern "C" void printExprHelper(Box* b);
 }
 
 #endif

src/codegen/irgen/hooks.cpp

@@ -366,13 +366,9 @@ static AST_Suite* parseExec(llvm::StringRef source, bool interactive = false) {
                 continue;
 
             AST_Expr* expr = (AST_Expr*)s;
-            AST_Print* print = new AST_Print;
-            print->lineno = expr->lineno;
-            print->col_offset = expr->col_offset;
-            print->dest = NULL;
-            print->nl = true;
-            print->values.push_back(expr->value);
-            parsedModule->body[i] = print;
+            AST_LangPrimitive* print_expr = new AST_LangPrimitive(AST_LangPrimitive::PRINT_EXPR);
+            print_expr->args.push_back(expr->value);
+            expr->value = print_expr;
         }
     }
 

src/codegen/irgen/irgenerator.cpp

@@ -879,6 +879,16 @@ private:
 
                 return getNone();
             }
+            case AST_LangPrimitive::PRINT_EXPR: {
+                assert(node->args.size() == 1);
+
+                CompilerVariable* obj = evalExpr(node->args[0], unw_info);
+                ConcreteCompilerVariable* converted = obj->makeConverted(emitter, obj->getBoxType());
+
+                emitter.createCall(unw_info, g.funcs.printExprHelper, converted->getValue());
+
+                return getNone();
+            }
             default:
                 RELEASE_ASSERT(0, "%d", node->opcode);
         }

src/codegen/runtime_hooks.cpp

@@ -29,6 +29,7 @@
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Transforms/Scalar.h"
 
+#include "codegen/ast_interpreter.h"
 #include "codegen/codegen.h"
 #include "codegen/irgen.h"
 #include "codegen/irgen/hooks.h"
@@ -233,6 +234,7 @@ void initGlobalFuncs(GlobalState& g) {
     GET(assertNameDefined);
     GET(assertFailDerefNameDefined);
     GET(assertFail);
+    GET(printExprHelper);
 
     GET(printFloat);
     GET(listAppendInternal);

src/codegen/runtime_hooks.h

@@ -41,7 +41,7 @@ struct GlobalFuncs {
 
     llvm::Value* unpackIntoArray, *raiseAttributeError, *raiseAttributeErrorStr, *raiseAttributeErrorCapi,
         *raiseAttributeErrorStrCapi, *raiseNotIterableError, *raiseIndexErrorStr, *raiseIndexErrorStrCapi,
-        *assertNameDefined, *assertFail, *assertFailDerefNameDefined;
+        *assertNameDefined, *assertFail, *assertFailDerefNameDefined, *printExprHelper;
     llvm::Value* printFloat, *listAppendInternal, *getSysStdout;
     llvm::Value* runtimeCall0, *runtimeCall1, *runtimeCall2, *runtimeCall3, *runtimeCall, *runtimeCallN;
     llvm::Value* callattr0, *callattr1, *callattr2, *callattr3, *callattr, *callattrN;

src/core/ast.h

@@ -1075,6 +1075,7 @@ public:
         SET_EXC_INFO,
         UNCACHE_EXC_INFO,
         HASNEXT,
+        PRINT_EXPR,
     } opcode;
     std::vector<AST_expr*> args;
 

src/jit.cpp

@@ -484,20 +484,9 @@ static int main(int argc, char** argv) {
 
                     if (m->body.size() > 0 && m->body[0]->type == AST_TYPE::Expr) {
                         AST_Expr* e = ast_cast<AST_Expr>(m->body[0]);
-                        AST_Call* c = new AST_Call();
-                        AST_Name* r = new AST_Name(m->interned_strings->get("repr"), AST_TYPE::Load, 0);
-                        c->func = r;
-                        c->starargs = NULL;
-                        c->kwargs = NULL;
-                        c->args.push_back(e->value);
-                        c->lineno = 0;
-
-                        AST_Print* p = new AST_Print();
-                        p->dest = NULL;
-                        p->nl = true;
-                        p->values.push_back(c);
-                        p->lineno = 0;
-                        m->body[0] = p;
+                        AST_LangPrimitive* print_expr = new AST_LangPrimitive(AST_LangPrimitive::PRINT_EXPR);
+                        print_expr->args.push_back(e->value);
+                        e->value = print_expr;
                     }
 
                     compileAndRunModule(m, main_module);

src/runtime/builtin_modules/sys.cpp

@@ -397,12 +397,60 @@ static PyObject* sys_excepthook(PyObject* self, PyObject* args) noexcept {
     return Py_None;
 }
 
+static PyObject* sys_displayhook(PyObject* self, PyObject* o) noexcept {
+    PyObject* outf;
+
+    // Pyston change: we currently hardcode the builtins module
+    /*
+    PyInterpreterState* interp = PyThreadState_GET()->interp;
+    PyObject* modules = interp->modules;
+    PyObject* builtins = PyDict_GetItemString(modules, "__builtin__");
+
+    if (builtins == NULL) {
+        PyErr_SetString(PyExc_RuntimeError, "lost __builtin__");
+        return NULL;
+    }
+    */
+    PyObject* builtins = builtins_module;
+
+    /* Print value except if None */
+    /* After printing, also assign to '_' */
+    /* Before, set '_' to None to avoid recursion */
+    if (o == Py_None) {
+        Py_INCREF(Py_None);
+        return Py_None;
+    }
+    if (PyObject_SetAttrString(builtins, "_", Py_None) != 0)
+        return NULL;
+    if (Py_FlushLine() != 0)
+        return NULL;
+    outf = PySys_GetObject("stdout");
+    if (outf == NULL) {
+        PyErr_SetString(PyExc_RuntimeError, "lost sys.stdout");
+        return NULL;
+    }
+    if (PyFile_WriteObject(o, outf, 0) != 0)
+        return NULL;
+    PyFile_SoftSpace(outf, 1);
+    if (Py_FlushLine() != 0)
+        return NULL;
+    if (PyObject_SetAttrString(builtins, "_", o) != 0)
+        return NULL;
+    Py_INCREF(Py_None);
+    return Py_None;
+}
+
 PyDoc_STRVAR(excepthook_doc, "excepthook(exctype, value, traceback) -> None\n"
                              "\n"
                              "Handle an exception by displaying it with a traceback on sys.stderr.\n");
 
+PyDoc_STRVAR(displayhook_doc, "displayhook(object) -> None\n"
+                              "\n"
+                              "Print an object to sys.stdout and also save it in __builtin__._\n");
+
 static PyMethodDef sys_methods[] = {
     { "excepthook", sys_excepthook, METH_VARARGS, excepthook_doc },
+    { "displayhook", sys_displayhook, METH_O, displayhook_doc },
 };
 
 void setupSys() {
@@ -507,6 +555,7 @@ void setupSys() {
         sys_module->giveAttr(md.ml_name, new BoxedCApiFunction(&md, sys_module));
     }
 
+    sys_module->giveAttr("__displayhook__", sys_module->getattr(internStringMortal("displayhook")));
     sys_module->giveAttr("flags", new BoxedSysFlags());
 }
 

src/runtime/inline/link_forcer.cpp

@@ -15,6 +15,7 @@
 // This file is for forcing the inclusion of function declarations into the stdlib.
 // This is so that the types of the functions are available to the compiler.
 
+#include "codegen/ast_interpreter.h"
 #include "codegen/irgen/hooks.h"
 #include "core/ast.h"
 #include "core/threading.h"
@@ -111,6 +112,7 @@ void force() {
     FORCE(assertNameDefined);
     FORCE(assertFailDerefNameDefined);
     FORCE(assertFail);
+    FORCE(printExprHelper);
 
     FORCE(strOrUnicode);
     FORCE(printFloat);

test/tests/compile_exec.py

@@ -30,3 +30,12 @@ print a, sorted(g.keys())
 print
 c = compile("a = 1; b = 2; a - b; b - a; c = a - b; c; print c", "test.py", "single")
 exec c
+
+exec compile("'hello world'", "test.py", "single")
+
+import sys
+def new_displayhook(arg):
+    print "my custom displayhook!"
+    print arg
+sys.displayhook = new_displayhook
+exec compile("'hello world'", "test.py", "single")

test/tests/doctest_test.py

-# expected: fail
 # requires:
 # - code.co_firstlineno
 # - sys.dysplayhook