From: Taylor R Campbell <campbell@mumble.net>
Date: Sun, 18 Nov 2018 01:44:49 +0000 (+0000)
Subject: Make (make-polar magnitude 0) return magnitude.
X-Git-Tag: mit-scheme-pucked-10.1.2~16^2~49
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=980cda77a35cfa557cb400633dd7053661ecc133;p=mit-scheme.git

Make (make-polar magnitude 0) return magnitude.
---

diff --git a/src/runtime/arith.scm b/src/runtime/arith.scm
index 03b1cacac..77a53f280 100644
--- a/src/runtime/arith.scm
+++ b/src/runtime/arith.scm
@@ -1916,8 +1916,10 @@ USA.
       (make-recnum real imag)))
 
 (define (complex:%make-polar magnitude angle)
-  (complex:%make-rectangular (real:* magnitude (real:cos angle))
-			     (real:* magnitude (real:sin angle))))
+  (if (real:exact0= angle)
+      magnitude
+      (complex:%make-rectangular (real:* magnitude (real:cos angle))
+				 (real:* magnitude (real:sin angle)))))
 
 (define (complex:real-part z)
   (cond ((recnum? z) (rec:real-part z))
diff --git a/tests/runtime/test-arith.scm b/tests/runtime/test-arith.scm
index 7c533512a..5b3774f8d 100644
--- a/tests/runtime/test-arith.scm
+++ b/tests/runtime/test-arith.scm
@@ -138,15 +138,10 @@ USA.
     (assert-nan (apply * l))))
 
 (define-enumerated-test 'polar0-real
-  (vector 0 0. -0. 1 1. -1.)
+  (vector 0 0. -0. 1 1. -1. (flo:+inf.0) (flo:-inf.0))
   (lambda (magnitude)
     (assert-real (make-polar magnitude 0))))
 
-(define-enumerated-test 'polar0-real-xfail
-  (vector (flo:+inf.0) (flo:-inf.0))
-  (lambda (magnitude)
-    (expect-failure (lambda () (assert-real (make-polar magnitude 0))))))
-
 (define-enumerated-test 'flo:ulp
   (vector
    (vector (flo:-inf.0) (flo:+inf.0))