[balsa] Meson build system changes

[Peter Bloomfield <peterb src gnome org>]

commit 01302b6adcc3dada1f466eb3022994f8f0fc47a4
Author: Peter Bloomfield <PeterBloomfield bellsouth net>
Date:   Sun Jan 21 14:56:51 2018 -0500

    Meson build system changes
    
    Meson build system changes to mirror the autotools changes in
    the previous commit
    
        * meson.build: check if the selected conversion tool
        accepts “--unicode-snob”.

 ChangeLog   |    8 ++++++++
 meson.build |    8 ++++++++
 2 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 8282951..86278b2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2018-01-21  Peter Bloomfield  <pbloomfield bellsouth net>
+
+       Meson build system changes to mirror the autotools changes in
+       the previous commit
+
+       * meson.build: check if the selected conversion tool
+       accepts “--unicode-snob”.
+
 2018-01-20  Albrecht Dreß <albrecht dress arcor de>
 
         Improve replying to html-only messages
diff --git a/meson.build b/meson.build
index 05ee26d..ee86e4f 100644
--- a/meson.build
+++ b/meson.build
@@ -218,6 +218,14 @@ elif html_widget == 'webkit' or html_widget == 'webkit2'
   if html2text.found()
     conf.set_quoted('HTML2TEXT', html2text.path(),
       description : 'Path to html2text program.')
+    conftest_htm = join_paths(meson.current_build_dir(), 'conftest.htm')
+    run_command('sh', '-c', 'echo "<html/>" > ' + conftest_htm)
+    unicode_snob = run_command(html2text.path(), '--unicode-snob', conftest_htm)
+    if unicode_snob.returncode() == 0
+      conf.set('HTML2TEXT_UCOPT', 1,
+        description : 'Defined when HTML2TEXT accepts the --unicode-snob option.')
+    endif
+    run_command('rm', '-f', conftest_htm)
   else
     message('You cannot properly quote html-only messags.')
   endif