Move the test macro detection code to unpythonic.syntax.testutil

Technologicat · Technologicat · commit 087bb6f0c51e · 2020-08-19T19:51:34.000+03:00
It doesn't really belong with the `nb` notebook macro.
Now it's where it belongs, and `nb` imports it.
diff --git a/unpythonic/syntax/nb.py b/unpythonic/syntax/nb.py
@@ -6,11 +6,11 @@
 
 # This is the kind of thing thinking with macros does to your program. ;)
 
-from ast import Expr, Subscript, Name, Call
+from ast import Expr
 
 from macropy.core.quotes import macros, q, ast_literal  # noqa: F401
 
-from .util import isx
+from .testutil import istestmacro
 
 def nb(body, args):
     p = args[0] if args else q[print]  # custom print function hook
@@ -20,6 +20,10 @@ def nb(body, args):
         theprint = ast_literal[p]
     newbody.extend(init)
     for stmt in body:
+        # We ignore statements (because no return value), and,
+        # test[] and related expressions from our test framework.
+        # Those don't return a value either, and play a role
+        # similar to the `assert` statement.
         if type(stmt) is not Expr or istestmacro(stmt.value):
             newbody.append(stmt)
             continue
@@ -29,22 +33,3 @@ def nb(body, args):
                 theprint(_)
         newbody.extend(newstmts)
     return newbody
-
-# Integration with the test framework - ignore test[] et al. expressions.
-#
-# See unpythonic.syntax.test.testutil and unpythonic.test.fixtures.
-# TODO: move istestmacro to testutil?
-_test_macro_names = ["test", "test_signals", "test_raises", "error", "fail"]
-_test_function_names = ["unpythonic_assert",
-                        "unpythonic_assert_signals",
-                        "unpythonic_assert_raises"]
-def istestmacro(tree):
-    def isunexpandedtestmacro(tree):
-        return (type(tree) is Subscript and
-                type(tree.value) is Name and
-                tree.value.id in _test_macro_names)
-    def isexpandedtestmacro(tree):
-        return (type(tree) is Call and
-                any(isx(tree.func, fname, accept_attr=False)
-                    for fname in _test_function_names))
-    return isunexpandedtestmacro(tree) or isexpandedtestmacro(tree)
diff --git a/unpythonic/syntax/testutil.py b/unpythonic/syntax/testutil.py
@@ -1,20 +1,51 @@
 # -*- coding: utf-8 -*-
-"""Utilities for writing tests."""
+"""Utilities for writing tests.
+
+See also `unpythonic.test.fixtures` for the high-level machinery.
+"""
 
 from macropy.core.quotes import macros, q, u, ast_literal, name
 from macropy.core.hquotes import macros, hq  # noqa: F811, F401
 from macropy.core import unparse
 
-from ast import Tuple, Str, copy_location
+from ast import Tuple, Str, Subscript, Name, Call, copy_location
 
 from ..dynassign import dyn  # for MacroPy's gen_sym
 from ..misc import callsite_filename
 from ..conditions import cerror, handlers, restarts, invoke
 from ..collections import box, unbox
 from ..symbol import sym
 
+from .util import isx
+
 from ..test import fixtures
 
+# -----------------------------------------------------------------------------
+# Helper for other macros to detect uses of the ones we define here.
+
+# Note the unexpanded `error[]` macro is distinguishable from a call to
+# the function `unpythonic.conditions.error`, because a macro invocation
+# is an `ast.Subscript`, whereas a function call is an `ast.Call`.
+_test_macro_names = ["test", "test_signals", "test_raises", "error", "fail"]
+_test_function_names = ["unpythonic_assert",
+                        "unpythonic_assert_signals",
+                        "unpythonic_assert_raises"]
+def istestmacro(tree):
+    """Return whether `tree` is an invocation of a testing macro.
+
+    Expanded or unexpanded doesn't matter; this is currently provided
+    so that other macros can detect and skip subtrees that invoke a test.
+    """
+    def isunexpandedtestmacro(tree):
+        return (type(tree) is Subscript and
+                type(tree.value) is Name and
+                tree.value.id in _test_macro_names)
+    def isexpandedtestmacro(tree):
+        return (type(tree) is Call and
+                any(isx(tree.func, fname, accept_attr=False)
+                    for fname in _test_function_names))
+    return isunexpandedtestmacro(tree) or isexpandedtestmacro(tree)
+
 # -----------------------------------------------------------------------------
 # Regular code, no macros yet.
 
