From: Neal Norwitz <nnorwitz@gmail.com>
Date: Sat, 15 Mar 2008 22:03:18 +0000 (+0000)
Subject: Add a warning for code like:
X-Git-Tag: v2.6a2~316
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=400aedacc06ac33c2bb488f3f95a90f11e96e168;p=python

Add a warning for code like:
  assert (0, 'message')

An empty tuple does not create a warning.  While questionable usage:
  assert (), 'message'

should not display a warning.  Tested manually.
The warning message could be improved.  Feel free to update it.
---

diff --git a/Misc/NEWS b/Misc/NEWS
index e778b8762d..ccb7baabcb 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,8 @@ What's New in Python 2.6 alpha 2?
 Core and builtins
 -----------------
 
+- Add a warning when asserting a non-empty tuple which is always true.
+
 - Issue #2179: speed up with statement execution by storing the exit method
   on the stack instead of in a temporary variable (patch by Jeffrey Yaskin)
 
diff --git a/Python/compile.c b/Python/compile.c
index 43b7569e62..47a63e7315 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -2056,6 +2056,14 @@ compiler_assert(struct compiler *c, stmt_ty s)
 		if (assertion_error == NULL)
 			return 0;
 	}
+	if (s->v.Assert.test->kind == Tuple_kind &&
+	    asdl_seq_LEN(s->v.Assert.test->v.Tuple.elts) > 0) {
+		const char* msg =
+			"assertion is always true, perhaps remove parentheses?";
+		if (PyErr_WarnExplicit(PyExc_SyntaxWarning, msg, c->c_filename,
+				       c->u->u_lineno, NULL, NULL) == -1)
+			return 0;
+	}
 	VISIT(c, expr, s->v.Assert.test);
 	end = compiler_new_block(c);
 	if (end == NULL)