Sync contrib/tools/python3 layout with upstream

* Move src/ subdir contents to the top of the layout
* Rename self-written lib -> lib2 to avoid CaseFolding warning from the VCS
* Regenerate contrib/libs/python proxy-headers accordingly
4ccc62ac1511abcf0fed14ccade38e984e088f1e

1 files changed, 109 insertions, 0 deletions

diff --git a/contrib/tools/python3/Python/future.c b/contrib/tools/python3/Python/future.c
new file mode 100644
index 0000000000..d56f733096
--- /dev/null
+++ b/contrib/tools/python3/Python/future.c
@@ -0,0 +1,109 @@
+#include "Python.h"
+#include "pycore_ast.h"           // _PyAST_GetDocString()
+
+#define UNDEFINED_FUTURE_FEATURE "future feature %.100s is not defined"
+
+static int
+future_check_features(PyFutureFeatures *ff, stmt_ty s, PyObject *filename)
+{
+    int i;
+
+    assert(s->kind == ImportFrom_kind);
+
+    asdl_alias_seq *names = s->v.ImportFrom.names;
+    for (i = 0; i < asdl_seq_LEN(names); i++) {
+        alias_ty name = (alias_ty)asdl_seq_GET(names, i);
+        const char *feature = PyUnicode_AsUTF8(name->name);
+        if (!feature)
+            return 0;
+        if (strcmp(feature, FUTURE_NESTED_SCOPES) == 0) {
+            continue;
+        } else if (strcmp(feature, FUTURE_GENERATORS) == 0) {
+            continue;
+        } else if (strcmp(feature, FUTURE_DIVISION) == 0) {
+            continue;
+        } else if (strcmp(feature, FUTURE_ABSOLUTE_IMPORT) == 0) {
+            continue;
+        } else if (strcmp(feature, FUTURE_WITH_STATEMENT) == 0) {
+            continue;
+        } else if (strcmp(feature, FUTURE_PRINT_FUNCTION) == 0) {
+            continue;
+        } else if (strcmp(feature, FUTURE_UNICODE_LITERALS) == 0) {
+            continue;
+        } else if (strcmp(feature, FUTURE_BARRY_AS_BDFL) == 0) {
+            ff->ff_features |= CO_FUTURE_BARRY_AS_BDFL;
+        } else if (strcmp(feature, FUTURE_GENERATOR_STOP) == 0) {
+            continue;
+        } else if (strcmp(feature, FUTURE_ANNOTATIONS) == 0) {
+            ff->ff_features |= CO_FUTURE_ANNOTATIONS;
+        } else if (strcmp(feature, "braces") == 0) {
+            PyErr_SetString(PyExc_SyntaxError,
+                            "not a chance");
+            PyErr_SyntaxLocationObject(filename, s->lineno, s->col_offset + 1);
+            return 0;
+        } else {
+            PyErr_Format(PyExc_SyntaxError,
+                         UNDEFINED_FUTURE_FEATURE, feature);
+            PyErr_SyntaxLocationObject(filename, s->lineno, s->col_offset + 1);
+            return 0;
+        }
+    }
+    return 1;
+}
+
+static int
+future_parse(PyFutureFeatures *ff, mod_ty mod, PyObject *filename)
+{
+    if (!(mod->kind == Module_kind || mod->kind == Interactive_kind)) {
+        return 1;
+    }
+
+    Py_ssize_t n = asdl_seq_LEN(mod->v.Module.body);
+    if (n == 0) {
+        return 1;
+    }
+
+    Py_ssize_t i = 0;
+    if (_PyAST_GetDocString(mod->v.Module.body) != NULL) {
+        i++;
+    }
+
+    for (; i < n; i++) {
+        stmt_ty s = (stmt_ty)asdl_seq_GET(mod->v.Module.body, i);
+
+        /* The only things that can precede a future statement
+         *  are another future statement and a doc string.
+         */
+
+        if (s->kind == ImportFrom_kind) {
+            identifier modname = s->v.ImportFrom.module;
+            if (modname &&
+                _PyUnicode_EqualToASCIIString(modname, "__future__")) {
+                if (!future_check_features(ff, s, filename)) {
+                    return 0;
+                }
+                ff->ff_location = SRC_LOCATION_FROM_AST(s);
+            }
+            else {
+                return 1;
+            }
+        }
+        else {
+            return 1;
+        }
+    }
+    return 1;
+}
+
+
+int
+_PyFuture_FromAST(mod_ty mod, PyObject *filename, PyFutureFeatures *ff)
+{
+    ff->ff_features = 0;
+    ff->ff_location = (_PyCompilerSrcLocation){-1, -1, -1, -1};
+
+    if (!future_parse(ff, mod, filename)) {
+        return 0;
+    }
+    return 1;
+}