[PATCH] configure: check existence of python3 setuptools and dev package

[Tomi Ollila]

The notmuch2 CFFI-based Python interface is not buildable unless
python3 dev package and python3 setuptools are installed.

Check that these exist in configure (and disable notmuch2 bindings
build if not) so that build of these bindings don't fail when make(1)
is executed.
---
 configure | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/configure b/configure
index 32a836bb..e4c738e5 100755
--- a/configure
+++ b/configure
@@ -711,12 +711,14 @@ if [ $have_python -eq 0 ]; then
     errors=$((errors + 1))
 fi
 
-have_python3=0
+have_python3_dev=0
 if [ $have_python -eq 1 ]; then
-    printf "Checking for python3..."
-    if "$python" -c 'import sys; assert sys.version_info >= (3,0)' > /dev/null 2>&1; then
+    printf "Checking for python3 dev..."
+    if "$python" -c 'import os, sys, sysconfig;
+assert sys.version_info >= (3,0)
+assert os.path.isfile(sysconfig.get_config_h_filename())' >/dev/null 2>&1; then
         printf "Yes.\n"
-        have_python3=1
+        have_python3_dev=1
     else
         printf "No.\n"
     fi
@@ -724,9 +726,9 @@ fi
 
 have_python3_cffi=0
 have_python3_pytest=0
-if [ $have_python3 -eq 1 ]; then
-    printf "Checking for python3 cffi... "
-    if "$python" -c 'import cffi' >/dev/null 2>&1; then
+if [ $have_python3_dev -eq 1 ]; then
+    printf "Checking for python3 cffi and setuptools... "
+    if "$python" -c 'import cffi; import setuptools' >/dev/null 2>&1; then
         printf "Yes.\n"
         have_python3_cffi=1
     else
-- 
2.25.1