From 9de85113674dca36f60e9dcc29f5302bf283c065 Mon Sep 17 00:00:00 2001
From: Tony Jinwoo Ahn <tony.jinwoo.ahn@gmail.com>
Date: Sat, 18 Sep 2021 19:42:09 +0900
Subject: [PATCH] Add tan() and tanh() for cmath

Signed-off-by: Tony Jinwoo Ahn <tony.jinwoo.ahn@gmail.com>
---
 Lib/test/test_cmath.py |  6 ++----
 vm/src/stdlib/cmath.rs | 12 ++++++++++++
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/Lib/test/test_cmath.py b/Lib/test/test_cmath.py
index 8dc0acab0e..0f4d1c7433 100644
--- a/Lib/test/test_cmath.py
+++ b/Lib/test/test_cmath.py
@@ -56,9 +56,9 @@ class CMathTests(unittest.TestCase):
     #
     # list of all functions in cmath
     test_functions = [getattr(cmath, fname) for fname in [
-        'sin','cos','log','log10','sqrt','acosh'
+        'sin','cos','log','log10','sqrt','acosh','tan','tanh'
         # 'exp','acos','asin','asinh',
-        # 'atan','atanh','sinh','cosh','tan','tanh'
+        # 'atan','atanh','sinh','cosh'
         ]]
     # test first and second arguments independently for 2-argument log
     # test_functions.append(lambda x : cmath.log(x, 1729. + 0j))
@@ -590,8 +590,6 @@ class CMathTests(unittest.TestCase):
         self.assertTrue(cmath.isinf(complex(NAN, INF)))
         self.assertTrue(cmath.isinf(complex(INF, NAN)))
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     @requires_IEEE_754
     def testTanhSign(self):
         for z in complex_zeros:
diff --git a/vm/src/stdlib/cmath.rs b/vm/src/stdlib/cmath.rs
index 4c8d605c5d..0d3dd9ceea 100644
--- a/vm/src/stdlib/cmath.rs
+++ b/vm/src/stdlib/cmath.rs
@@ -113,6 +113,18 @@ mod cmath {
         z.to_complex().acosh()
     }
 
+    /// Return the tangent of z.
+    #[pyfunction]
+    fn tan(z: IntoPyComplex) -> Complex64 {
+        z.to_complex().tan()
+    }
+
+    /// Return the hyperbolic tangent of z.
+    #[pyfunction]
+    fn tanh(z: IntoPyComplex) -> Complex64 {
+        z.to_complex().tanh()
+    }
+
     #[derive(FromArgs)]
     struct IsCloseArgs {
         #[pyarg(positional)]