[pitivi] meson: Support Python 3.8

[Alexandru Băluț <alexbalut src gnome org>]

commit 0a3cc054a2c20b59f5aaaaa307de3c9af3c0d270
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Tue Jan 28 22:34:40 2020 +0100

    meson: Support Python 3.8
    
    To link to Python we need to use python-3.8-embed.

 meson.build       | 13 ++++++++++---
 meson_options.txt |  3 ++-
 2 files changed, 12 insertions(+), 4 deletions(-)
---
diff --git a/meson.build b/meson.build
index 0885329f..060ab47a 100644
--- a/meson.build
+++ b/meson.build
@@ -1,9 +1,16 @@
-project('pitivi', 'c', version : '1.90.0.1', meson_version : '>= 0.41.0')
+project('pitivi', 'c', version : '1.90.0.1', meson_version : '>= 0.46.0')
 host_system = host_machine.system()
 
-python = find_program('python3')
+pymod = import('python')
+python = pymod.find_installation(get_option('python'))
+pythonver = python.language_version()
+# Workaround for https://github.com/mesonbuild/meson/issues/5629
+# https://gitlab.freedesktop.org/gstreamer/gst-python/issues/28
+python_dep = dependency('python-@0@-embed'.format(pythonver), version: '>= 3.3', required: false)
+if not python_dep.found()
+  python_dep = python.dependency('python3', version: '>= 3.3')
+endif
 
-python_dep = dependency('python3', version : '>= 3.3')
 if get_option('build-gst')
     subproject('gst-build', default_options: ['enable_python=true',
         'disable_gstreamer_sharp=true', 'disable_rtsp_server=true',
diff --git a/meson_options.txt b/meson_options.txt
index c6590dd1..7d6bad29 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -1,2 +1,3 @@
-option('disable-help', type : 'boolean', value : false)
 option('build-gst', type : 'boolean', value : false)
+option('disable-help', type : 'boolean', value : false)
+option('python', type : 'string', value : 'python3')