[elpa] externals-release/org c50b03d99e: lisp/ob-C.el: replace %f with %s to prevent unneeded rounding

[ELPA Syncer]

branch: externals-release/org
commit c50b03d99e3b13ff311e66422cc3916791f37f68
Author: Leo Butler <leo.butler@umanitoba.ca>
Commit: Ihor Radchenko <yantar92@posteo.net>

    lisp/ob-C.el: replace %f with %s to prevent unneeded rounding
    
    * lisp/ob-C.el (org-babel-C-val-to-C-type): Floats should be printed
    as string literals to prevent rounding introduced by %f format.
    
    * testing/lisp/test-ob-C.el (ob-C/float-var): Test that floats are not
    rounded when passed as an org :var.
---
 lisp/ob-C.el              |  2 +-
 testing/lisp/test-ob-C.el | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/lisp/ob-C.el b/lisp/ob-C.el
index 3a6e99623f..7763c4c07c 100644
--- a/lisp/ob-C.el
+++ b/lisp/ob-C.el
@@ -339,7 +339,7 @@ FORMAT can be either a format string or a function which is 
called with VAL."
         (type
          (pcase basetype
            (`integerp '("int" "%d"))
-           (`floatp '("double" "%f"))
+           (`floatp '("double" "%s")) ;; %f rounds, use %s to print the float 
literally
            (`stringp
             (list
              (if (eq org-babel-c-variant 'd) "string" "const char*")
diff --git a/testing/lisp/test-ob-C.el b/testing/lisp/test-ob-C.el
index b6dbed8e31..8546a48dda 100644
--- a/testing/lisp/test-ob-C.el
+++ b/testing/lisp/test-ob-C.el
@@ -95,6 +95,17 @@
                      (org-babel-next-src-block 10)
                      (should (= 42 (org-babel-execute-src-block))))))
 
+(ert-deftest ob-C/float-var ()
+  "Test that floats are passed without unnecessary rounding."
+  (if (executable-find org-babel-C++-compiler)
+      (org-test-with-temp-text 
+"#+source: float_var
+#+begin_src cpp :var x=1.123456789012345678 :includes \"<iostream>\" :results 
silent
+double y = 1.123456789012345678;
+std::cout << (x == y);
+#+end_src"
+(should (= 1 (org-babel-execute-src-block))))))
+
 (ert-deftest ob-C/table ()
   "Test of a table output"
   (if (executable-find org-babel-C++-compiler)