Refactor future feature handling

Replace uses of PyCF_xxx with CO_xxx.

Replace individual feature slots in PyFutureFeatures with single
bitmask ff_features.

When flags must be transfered among the three parts of the interpreter
that care about them -- the pythonrun layer, the compiler, and the
future feature parser -- can simply or (|) the definitions.

4 files changed, 17 insertions, 52 deletions

diff --git a/Python/ceval.c b/Python/ceval.c
index 583d7e3..bf85f11 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -2937,11 +2937,11 @@ PyEval_MergeCompilerFlags(PyCompilerFlags *cf)
 		const int codeflags = current_frame->f_code->co_flags;
 		if (codeflags & CO_NESTED) {
 			result = 1;
-			cf->cf_flags |= PyCF_NESTED_SCOPES;
+			cf->cf_flags |= CO_NESTED;
 		}
 		if (codeflags & CO_GENERATOR_ALLOWED) {
 			result = 1;
-			cf->cf_flags |= PyCF_GENERATORS;
+			cf->cf_flags |= CO_GENERATOR_ALLOWED;
 		}
 	}
 	return result;
diff --git a/Python/compile.c b/Python/compile.c
index d310e35..66cd00a 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -3967,22 +3967,8 @@ jcompile(node *n, char *filename, struct compiling *base,
 			com_free(&sc);
 			return NULL;
 		}
-		if (flags) {
-			if (flags->cf_flags & PyCF_NESTED_SCOPES)
-				sc.c_future->ff_nested_scopes = 1;
-			else if (sc.c_future->ff_nested_scopes)
-				flags->cf_flags |= PyCF_NESTED_SCOPES;
-
-			if (flags->cf_flags & PyCF_GENERATORS)
-				sc.c_future->ff_generators = 1;
-			else if (sc.c_future->ff_generators)
-				flags->cf_flags |= PyCF_GENERATORS;
-
-			if (flags->cf_flags & PyCF_DIVISION)
-				sc.c_future->ff_division = 1;
-			else if (sc.c_future->ff_division)
-				flags->cf_flags |= PyCF_DIVISION;
-		}
+		if (flags)
+			sc.c_future->ff_features |= flags->cf_flags;
 		if (symtable_build(&sc, n) < 0) {
 			com_free(&sc);
 			return NULL;
@@ -4150,8 +4136,6 @@ symtable_build(struct compiling *c, node *n)
 	if ((c->c_symtable = symtable_init()) == NULL)
 		return -1;
 	c->c_symtable->st_future = c->c_future;
-	if (c->c_future->ff_nested_scopes)
-		c->c_symtable->st_nested_scopes = 1;
 	c->c_symtable->st_filename = c->c_filename;
 	symtable_enter_scope(c->c_symtable, TOP, TYPE(n), n->n_lineno);
 	if (c->c_symtable->st_errors > 0)
@@ -4451,14 +4435,8 @@ static int
 symtable_update_flags(struct compiling *c, PySymtableEntryObject *ste,
 		      struct symbol_info *si)
 {
-	if (c->c_future) {
-		if (c->c_future->ff_nested_scopes)
-			c->c_flags |= CO_NESTED;
-		if (c->c_future->ff_generators)
-			c->c_flags |= CO_GENERATOR_ALLOWED;
-		if (c->c_future->ff_division)
-			c->c_flags |= CO_FUTURE_DIVISION;
-	}
+	if (c->c_future)
+		c->c_flags |= c->c_future->ff_features;
 	if (ste->ste_generator)
 		c->c_flags |= CO_GENERATOR;
 	if (ste->ste_type != TYPE_MODULE)
@@ -4617,7 +4595,6 @@ symtable_init()
 	if (st == NULL)
 		return NULL;
 	st->st_pass = 1;
-	st->st_nested_scopes = NESTED_SCOPES_DEFAULT;
 	st->st_filename = NULL;
 	if ((st->st_stack = PyList_New(0)) == NULL)
 		goto fail;
diff --git a/Python/future.c b/Python/future.c
index db62b5b..6b1c0c5 100644
--- a/Python/future.c
+++ b/Python/future.c
@@ -30,11 +30,11 @@ future_check_features(PyFutureFeatures *ff, node *n, char *filename)
 		REQ(ch, import_as_name);
 		feature = STR(CHILD(ch, 0));
 		if (strcmp(feature, FUTURE_NESTED_SCOPES) == 0) {
-			ff->ff_nested_scopes = 1;
+			continue;
 		} else if (strcmp(feature, FUTURE_GENERATORS) == 0) {
-			ff->ff_generators = 1;
+			ff->ff_features |= CO_GENERATOR_ALLOWED;
 		} else if (strcmp(feature, FUTURE_DIVISION) == 0) {
-			ff->ff_division = 1;
+			ff->ff_features |= CO_FUTURE_DIVISION;
 		} else if (strcmp(feature, "braces") == 0) {
 			PyErr_SetString(PyExc_SyntaxError,
 					"not a chance");
@@ -234,9 +234,7 @@ PyNode_Future(node *n, char *filename)
 		return NULL;
 	ff->ff_found_docstring = 0;
 	ff->ff_last_lineno = -1;
-	ff->ff_nested_scopes = 0;
-	ff->ff_generators = 0;
-	ff->ff_division = 0;
+	ff->ff_features = 0;
 
 	if (future_parse(ff, n, filename) < 0) {
 		PyMem_Free((void *)ff);
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index 69a7b51..f5fcaf1 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -556,7 +556,7 @@ PyRun_InteractiveOneFlags(FILE *fp, char *filename, PyCompilerFlags *flags)
 	n = PyParser_ParseFileFlags(fp, filename, &_PyParser_Grammar,
 			    	    Py_single_input, ps1, ps2, &err,
 			    	    (flags &&
-			    	     flags->cf_flags & PyCF_GENERATORS) ?
+			    	     flags->cf_flags & CO_GENERATOR_ALLOWED) ?
 			    	    	PyPARSE_YIELD_IS_KEYWORD : 0);
 	Py_XDECREF(v);
 	Py_XDECREF(w);
@@ -1009,8 +1009,8 @@ PyRun_StringFlags(char *str, int start, PyObject *globals, PyObject *locals,
 		  PyCompilerFlags *flags)
 {
 	return run_err_node(PyParser_SimpleParseStringFlags(
-				str, start,
-				(flags && flags->cf_flags & PyCF_GENERATORS) ?
+			str, start,
+			(flags && flags->cf_flags & CO_GENERATOR_ALLOWED) ?
 				PyPARSE_YIELD_IS_KEYWORD : 0),
 			    "<string>", globals, locals, flags);
 }
@@ -1028,7 +1028,7 @@ PyRun_FileExFlags(FILE *fp, char *filename, int start, PyObject *globals,
 		  PyObject *locals, int closeit, PyCompilerFlags *flags)
 {
 	node *n = PyParser_SimpleParseFileFlags(fp, filename, start,
-			(flags && flags->cf_flags & PyCF_GENERATORS) ?
+			(flags && flags->cf_flags & CO_GENERATOR_ALLOWED) ?
 				PyPARSE_YIELD_IS_KEYWORD : 0);
 	if (closeit)
 		fclose(fp);
@@ -1085,18 +1085,8 @@ run_pyc_file(FILE *fp, char *filename, PyObject *globals, PyObject *locals,
 	}
 	co = (PyCodeObject *)v;
 	v = PyEval_EvalCode(co, globals, locals);
-	if (v && flags) {
-		if (co->co_flags & CO_NESTED)
-			flags->cf_flags |= PyCF_NESTED_SCOPES;
-		if (co->co_flags & CO_GENERATOR_ALLOWED)
-			flags->cf_flags |= PyCF_GENERATORS;
-#if 0
-		fprintf(stderr, "run_pyc_file: nested_scopes: %d\n",
-			flags->cf_flags & PyCF_NESTED_SCOPES);
-		fprintf(stderr, "run_pyc_file: generators: %d\n",
-			flags->cf_flags & PyCF_GENERATORS);
-#endif
-	}
+	if (v && flags)
+		flags->cf_flags |= (co->co_flags & PyCF_MASK);
 	Py_DECREF(co);
 	return v;
 }
@@ -1114,7 +1104,7 @@ Py_CompileStringFlags(char *str, char *filename, int start,
 	node *n;
 	PyCodeObject *co;
 	n = PyParser_SimpleParseStringFlags(str, start,
-		(flags && flags->cf_flags & PyCF_GENERATORS) ?
+		(flags && flags->cf_flags & CO_GENERATOR_ALLOWED) ?
 			PyPARSE_YIELD_IS_KEYWORD : 0);
 	if (n == NULL)
 		return NULL;