[gegl/abderrahim/meson-python-fix] meson: use python installation found by meson

[Abderrahim Kitouni <akitouni src gnome org>]

commit ccd6279f4a4a742e72c55931c831fd5da3592fc4
Author: Abderrahim Kitouni <akitouni gnome org>
Date:   Thu Aug 15 23:19:00 2019 +0100

    meson: use python installation found by meson
    
    This is more robust than looking for "python" in the PATH, as /usr/bin/python
    might not exist when only python3 is available.

 opencl/meson.build             | 2 +-
 tests/compositions/meson.build | 2 +-
 tests/python/meson.build       | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/opencl/meson.build b/opencl/meson.build
index 6c5bee0a2..e00b860d4 100644
--- a/opencl/meson.build
+++ b/opencl/meson.build
@@ -56,6 +56,6 @@ foreach source : opencl_sources
   opencl_headers += custom_target(source + '.h',
     input : source,
     output: source +'.h',
-    command: [ cltostring, '@INPUT@', '@OUTPUT@' ],
+    command: [ python, cltostring, '@INPUT@', '@OUTPUT@' ],
   )
 endforeach
diff --git a/tests/compositions/meson.build b/tests/compositions/meson.build
index 268eda4ec..b30955d9a 100644
--- a/tests/compositions/meson.build
+++ b/tests/compositions/meson.build
@@ -73,7 +73,7 @@ run_compositions = find_program('run-compositions.py')
 
 if false
 test('compositions_with_opencl',
-  run_compositions,
+  [ python, run_compositions ],
   args: [
     '--build-dir='+ meson.build_root(),
     '--src-dir='  + meson.source_root(),
diff --git a/tests/python/meson.build b/tests/python/meson.build
index f0f9c5868..c92f8a4a3 100644
--- a/tests/python/meson.build
+++ b/tests/python/meson.build
@@ -11,7 +11,7 @@ if python.found() and pygobject_found
   foreach testname : testnames
     testfile = 'test-' + testname + '.py'
     test(testname,
-      find_program(testfile),
+      [ python, find_program(testfile) ],
       env: [
         'LD_LIBRARY_PATH=' + meson.build_root() / 'gegl' + ':$LD_LIBRARY_PATH',
         'GI_TYPELIB_PATH=' + meson.build_root() / 'gegl' + ':$GI_TYPELIB_PATH',