py3: ensure python output is not lost

Unbuffer python's stdio to avoid output getting stuck in buffer when
stdout is not a TTY. Normally buffers are flushed by `Py_Finalize` but
Boost has a long-standing issue preventing the proper shutdown of the
interpreter with `Py_Finalize` when embedded [1].

This applies the same fix as 139beba but to any ledger usage rather than
only the test suite. I removed `PYTHONUNBUFFERED=1` from tests as there
is no expectation that users should need to have this set for ledger to
function.

For example without this fix piping ledger into cat usually loses any
output (unless the output is large enough to cause the buffer to flush):

    $ ./ledger -f "test/baseline/feat-value_py3.test" reg
    <class 'bool'> True
    [...]
    $ ./ledger -f "test/baseline/feat-value_py3.test" reg | cat
    $

Interestingly `--verify` causes `python_interpreter_t` to be destroyed
-- it doesn't appear to be otherwise -- which does call `Py_Finalize`.
As expected this fixes the issue but can also crash due to the boost
issue mentioned above:

    $ ./ledger -f "test/baseline/feat-value_py3.test" --verify reg
    <class 'bool'> True
    [...]
    Segmentation fault (core dumped)
    $ ./ledger -f "test/baseline/feat-value_py3.test" --verify reg | cat
    <class 'bool'> True
    [...]
    $

1. https://www.boost.org/doc/libs/1_62_0/libs/python/doc/html/tutorial/tutorial/embedding.html

1 files changed, 3 insertions, 3 deletions

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index a0905004..c1dde710 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -34,7 +34,7 @@ macro(add_ledger_harness_tests _class)
           $<TARGET_FILE:ledger> ${PROJECT_SOURCE_DIR}
           ${TestFile} ${TEST_PYTHON_FLAGS})
         set_tests_properties(${_class}Test_${TestFile_Name}
-          PROPERTIES ENVIRONMENT "PYTHONUNBUFFERED=1;TZ=${Ledger_TEST_TIMEZONE}")
+          PROPERTIES ENVIRONMENT "TZ=${Ledger_TEST_TIMEZONE}")
       endif()
     endforeach()
   endif()
@@ -53,7 +53,7 @@ if (Python_EXECUTABLE)
       COMMAND ${Python_EXECUTABLE} ${PROJECT_SOURCE_DIR}/test/${_class}.py
       --ledger $<TARGET_FILE:ledger> --file ${TestFile})
     set_tests_properties(${_class}Test_${TestFile_Name}
-      PROPERTIES ENVIRONMENT "PYTHONUNBUFFERED=1;TZ=${Ledger_TEST_TIMEZONE}")
+      PROPERTIES ENVIRONMENT "TZ=${Ledger_TEST_TIMEZONE}")
   endforeach()
 
   # CheckManpage and CheckTexinfo are disabled, since they do not work
@@ -64,7 +64,7 @@ if (Python_EXECUTABLE)
       COMMAND ${Python_EXECUTABLE} ${PROJECT_SOURCE_DIR}/test/${_class}.py
       --ledger $<TARGET_FILE:ledger> --source ${PROJECT_SOURCE_DIR})
     set_tests_properties(${_class}
-      PROPERTIES ENVIRONMENT "PYTHONUNBUFFERED=1;TZ=${Ledger_TEST_TIMEZONE}")
+      PROPERTIES ENVIRONMENT "TZ=${Ledger_TEST_TIMEZONE}")
   endforeach()
 endif()